[svn-r27327] svn merge -r27208:27326 https://svn.hdfgroup.uiuc.edu/hdf5/trunk

90 files changed, 14837 insertions, 11602 deletions

diff --git a/src/H5AC.c b/src/H5AC.c
index db5a06f..a94a727 100644
--- a/src/H5AC.c
+++ b/src/H5AC.c
@@ -32,7 +32,6 @@
 /****************/
 
 #define H5AC_PACKAGE            /*suppress error about including H5ACpkg  */
-#define H5C_PACKAGE             /*suppress error about including H5Cpkg   */
 #define H5F_PACKAGE		/*suppress error about including H5Fpkg	  */
 
 /* Interface initialization */
@@ -43,14 +42,11 @@
 /***********/
 #include "H5private.h"		/* Generic Functions			*/
 #include "H5ACpkg.h"		/* Metadata cache			*/
-#include "H5Cpkg.h"             /* Cache                                */
-#include "H5Dprivate.h"		/* Dataset functions			*/
+#include "H5Cprivate.h"		/* Cache                                */
 #include "H5Eprivate.h"		/* Error handling		  	*/
 #include "H5Fpkg.h"		/* Files				*/
 #include "H5FDprivate.h"	/* File drivers				*/
-#include "H5FLprivate.h"        /* Free Lists                           */
 #include "H5Iprivate.h"		/* IDs			  		*/
-#include "H5MMprivate.h"        /* Memory management                    */
 #include "H5Pprivate.h"         /* Property lists                       */
 
 
@@ -63,38 +59,6 @@
 /* Local Typedefs */
 /******************/
 
-#ifdef H5_HAVE_PARALLEL
-/****************************************************************************
- *
- * structure H5AC_slist_entry_t
- *
- * The dirty entry list maintained via the d_slist_ptr field of H5AC_aux_t
- * and the cleaned entry list maintained via the c_slist_ptr field of
- * H5AC_aux_t are just lists of the file offsets of the dirty/cleaned
- * entries.  Unfortunately, the slist code makes us define a dynamically
- * allocated structure to store these offsets in.  This structure serves
- * that purpose.  Its fields are as follows:
- *
- * addr:	file offset of a metadata entry.  Entries are added to this
- *		list (if they aren't there already) when they are marked
- *		dirty in an unprotect, inserted, or moved.  They are
- *		removed when they appear in a clean entries broadcast.
- *
- ****************************************************************************/
-typedef struct H5AC_slist_entry_t
-{
-    haddr_t     addr;
-} H5AC_slist_entry_t;
-
-/* User data for address list building callbacks */
-typedef struct H5AC_addr_list_ud_t
-{
-    H5AC_aux_t    * aux_ptr;        /* 'Auxiliary' parallel cache info */
-    haddr_t       * addr_buf_ptr;   /* Array to store addresses */
-    int             i;              /* Counter for position in array */
-} H5AC_addr_list_ud_t;
-#endif /* H5_HAVE_PARALLEL */
-
 
 /********************/
 /* Local Prototypes */
@@ -105,40 +69,6 @@ static herr_t H5AC__check_if_write_permitted(const H5F_t *f,
 static herr_t H5AC__ext_config_2_int_config(H5AC_cache_config_t *ext_conf_ptr,
     H5C_auto_size_ctl_t *int_conf_ptr);
 
-#ifdef H5_HAVE_PARALLEL
-static herr_t H5AC__broadcast_candidate_list(H5AC_t *cache_ptr,
-    int *num_entries_ptr, haddr_t **haddr_buf_ptr_ptr);
-static herr_t H5AC__broadcast_clean_list(H5AC_t *cache_ptr);
-static herr_t H5AC__construct_candidate_list(H5AC_t *cache_ptr,
-    H5AC_aux_t *aux_ptr, int sync_point_op);
-static herr_t H5AC__copy_candidate_list_to_buffer(const H5AC_t *cache_ptr,
-    int *num_entries_ptr, haddr_t **haddr_buf_ptr_ptr);
-static herr_t H5AC__flush_entries(H5F_t *f, hid_t dxpl_id);
-static herr_t H5AC__log_deleted_entry(const H5AC_info_t *entry_ptr);
-static herr_t H5AC__log_dirtied_entry(const H5AC_info_t *entry_ptr);
-static herr_t H5AC__log_flushed_entry(H5C_t *cache_ptr, haddr_t addr,
-    hbool_t was_dirty, unsigned flags);
-static herr_t H5AC__log_inserted_entry(const H5AC_info_t *entry_ptr);
-static herr_t H5AC__log_moved_entry(const H5F_t *f, haddr_t old_addr,
-    haddr_t new_addr);
-static herr_t H5AC__propagate_and_apply_candidate_list(H5F_t  *f, hid_t dxpl_id);
-static herr_t H5AC__propagate_flushed_and_still_clean_entries_list(H5F_t  *f,
-    hid_t dxpl_id);
-static herr_t H5AC__receive_haddr_list(MPI_Comm mpi_comm, int *num_entries_ptr,
-    haddr_t **haddr_buf_ptr_ptr);
-static herr_t H5AC__receive_candidate_list(const H5AC_t *cache_ptr,
-    int *num_entries_ptr, haddr_t **haddr_buf_ptr_ptr);
-static herr_t H5AC__receive_and_apply_clean_list(H5F_t *f, hid_t primary_dxpl_id,
-    hid_t secondary_dxpl_id);
-static herr_t H5AC__tidy_cache_0_lists(H5AC_t *cache_ptr, int num_candidates,
-    haddr_t *candidates_list_ptr);
-static herr_t H5AC__rsp__dist_md_write__flush(H5F_t *f, hid_t dxpl_id);
-static herr_t H5AC__rsp__dist_md_write__flush_to_min_clean(H5F_t *f, hid_t dxpl_id);
-static herr_t H5AC__rsp__p0_only__flush(H5F_t *f, hid_t dxpl_id);
-static herr_t H5AC__rsp__p0_only__flush_to_min_clean(H5F_t *f, hid_t dxpl_id);
-static herr_t H5AC__run_sync_point(H5F_t *f, hid_t dxpl_id, int sync_point_op);
-#endif /* H5_HAVE_PARALLEL */
-
 
 /*********************/
 /* Package Variables */
@@ -165,14 +95,6 @@ hid_t H5AC_ind_dxpl_id = (-1);
 /* Local Variables */
 /*******************/
 
-#ifdef H5_HAVE_PARALLEL
-/* Declare a free list to manage the H5AC_aux_t struct */
-H5FL_DEFINE_STATIC(H5AC_aux_t);
-
-/* Declare a free list to manage the H5AC_slist_entry_t struct */
-H5FL_DEFINE_STATIC(H5AC_slist_entry_t);
-#endif /* H5_HAVE_PARALLEL */
-
 static const char *H5AC_entry_type_names[H5AC_NTYPES] =
 {
     "B-tree nodes",
@@ -201,6 +123,7 @@ static const char *H5AC_entry_type_names[H5AC_NTYPES] =
     "fixed array data block",
     "fixed array data block pages",
     "superblock",
+    "driver info",
     "test entry"	/* for testing only -- not used for actual files */
 };
 
@@ -564,7 +487,7 @@ H5AC_dest(H5F_t *f, hid_t dxpl_id)
 #endif /* H5AC__TRACE_FILE_ENABLED */
 
 #ifdef H5_HAVE_PARALLEL
-    aux_ptr = (struct H5AC_aux_t *)(f->shared->cache->aux_ptr);
+    aux_ptr = H5C_get_aux_ptr(f->shared->cache);
     if(aux_ptr)
         /* Sanity check */
         HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
@@ -575,7 +498,7 @@ H5AC_dest(H5F_t *f, hid_t dxpl_id)
 #endif /* H5_HAVE_PARALLEL */
 
     /* Destroy the cache */
-    if(H5C_dest(f, dxpl_id, H5AC_dxpl_id) < 0)
+    if(H5C_dest(f, dxpl_id) < 0)
         HGOTO_ERROR(H5E_CACHE, H5E_CANTFREE, FAIL, "can't destroy cache")
     f->shared->cache = NULL;
 
@@ -628,8 +551,7 @@ H5AC_expunge_entry(H5F_t *f, hid_t dxpl_id, const H5AC_class_t *type,
     HDassert(f->shared);
     HDassert(f->shared->cache);
     HDassert(type);
-    HDassert(type->clear);
-    HDassert(type->dest);
+    HDassert(type->serialize);
     HDassert(H5F_addr_defined(addr));
 
 #if H5AC__TRACE_FILE_ENABLED
@@ -645,7 +567,7 @@ H5AC_expunge_entry(H5F_t *f, hid_t dxpl_id, const H5AC_class_t *type,
 }
 #endif /* H5AC__TRACE_FILE_ENABLED */
 
-    if(H5C_expunge_entry(f, dxpl_id, H5AC_dxpl_id, type, addr, flags) < 0)
+    if(H5C_expunge_entry(f, dxpl_id, type, addr, flags) < 0)
         HGOTO_ERROR(H5E_CACHE, H5E_CANTEXPUNGE, FAIL, "H5C_expunge_entry() failed.")
 
 done:
@@ -710,7 +632,7 @@ H5AC_flush(H5F_t *f, hid_t dxpl_id)
 
     /* Flush the cache */
     /* (Again, in parallel - writes out the superblock) */
-    if(H5C_flush_cache(f, dxpl_id, H5AC_dxpl_id, H5AC__NO_FLAGS_SET) < 0)
+    if(H5C_flush_cache(f, dxpl_id, H5AC__NO_FLAGS_SET) < 0)
         HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "Can't flush cache.")
 
 done:
@@ -818,8 +740,7 @@ H5AC_insert_entry(H5F_t *f, hid_t dxpl_id, const H5AC_class_t *type, haddr_t add
     HDassert(f->shared);
     HDassert(f->shared->cache);
     HDassert(type);
-    HDassert(type->flush);
-    HDassert(type->size);
+    HDassert(type->serialize);
     HDassert(H5F_addr_defined(addr));
     HDassert(thing);
 
@@ -841,7 +762,7 @@ H5AC_insert_entry(H5F_t *f, hid_t dxpl_id, const H5AC_class_t *type, haddr_t add
 #endif /* H5AC__TRACE_FILE_ENABLED */
 
     /* Insert entry into metadata cache */
-    if(H5C_insert_entry(f, dxpl_id, H5AC_dxpl_id, type, addr, thing, flags) < 0)
+    if(H5C_insert_entry(f, dxpl_id, type, addr, thing, flags) < 0)
         HGOTO_ERROR(H5E_CACHE, H5E_CANTINS, FAIL, "H5C_insert_entry() failed")
 
 #if H5AC__TRACE_FILE_ENABLED
@@ -854,7 +775,7 @@ H5AC_insert_entry(H5F_t *f, hid_t dxpl_id, const H5AC_class_t *type, haddr_t add
 {
     H5AC_aux_t *aux_ptr;
 
-    if(NULL != (aux_ptr = (H5AC_aux_t *)f->shared->cache->aux_ptr)) {
+    if(NULL != (aux_ptr = H5C_get_aux_ptr(f->shared->cache))) {
         /* Log the new entry */
         if(H5AC__log_inserted_entry((H5AC_info_t *)thing) < 0)
             HGOTO_ERROR(H5E_CACHE, H5E_CANTINS, FAIL, "H5AC__log_inserted_entry() failed")
@@ -918,12 +839,11 @@ H5AC_mark_entry_dirty(void *thing)
 {
     H5AC_info_t *entry_ptr = (H5AC_info_t *)thing;
     H5C_t *cache_ptr = entry_ptr->cache_ptr;
+    H5AC_aux_t *aux_ptr;
 
-    HDassert(cache_ptr);
-    HDassert(cache_ptr->magic == H5C__H5C_T_MAGIC);
-
+    aux_ptr = H5C_get_aux_ptr(cache_ptr);
     if((!entry_ptr->is_dirty) && (!entry_ptr->is_protected) &&
-             (entry_ptr->is_pinned) && (NULL != cache_ptr->aux_ptr))
+             (entry_ptr->is_pinned) && (NULL != aux_ptr))
         if(H5AC__log_dirtied_entry(entry_ptr) < 0)
             HGOTO_ERROR(H5E_CACHE, H5E_CANTMARKDIRTY, FAIL, "can't log dirtied entry")
 }
@@ -990,7 +910,7 @@ H5AC_move_entry(H5F_t *f, const H5AC_class_t *type, haddr_t old_addr, haddr_t ne
 
 #ifdef H5_HAVE_PARALLEL
     /* Log moving the entry */
-    if(NULL != (aux_ptr = (H5AC_aux_t *)f->shared->cache->aux_ptr))
+    if(NULL != (aux_ptr = H5C_get_aux_ptr(f->shared->cache)))
         if(H5AC__log_moved_entry(f, old_addr, new_addr) < 0)
             HGOTO_ERROR(H5E_CACHE, H5E_CANTUNPROTECT, FAIL, "can't log moved entry")
 #endif /* H5_HAVE_PARALLEL */
@@ -1138,9 +1058,8 @@ done:
  */
 void *
 H5AC_protect(H5F_t *f, hid_t dxpl_id, const H5AC_class_t *type, haddr_t addr,
-    void *udata, H5AC_protect_t rw)
+    void *udata, unsigned flags)
 {
-    unsigned		protect_flags = H5C__NO_FLAGS_SET;
     void *		thing;          /* Pointer to native data structure for entry */
 #if H5AC__TRACE_FILE_ENABLED
     char                trace[128] = "";
@@ -1156,47 +1075,36 @@ H5AC_protect(H5F_t *f, hid_t dxpl_id, const H5AC_class_t *type, haddr_t addr,
     HDassert(f->shared);
     HDassert(f->shared->cache);
     HDassert(type);
-    HDassert(type->flush);
-    HDassert(type->load);
+    HDassert(type->serialize);
     HDassert(H5F_addr_defined(addr));
 
+    /* Check for unexpected flags -- H5C__FLUSH_COLLECTIVELY_FLAG
+     * only permitted in the parallel case.
+     */
+#ifdef H5_HAVE_PARALLEL
+    HDassert(0 == (flags & (unsigned)(~(H5C__READ_ONLY_FLAG | \
+                                        H5C__FLUSH_LAST_FLAG | \
+                                        H5C__FLUSH_COLLECTIVELY_FLAG))));
+#else /* H5_HAVE_PARALLEL */
+    HDassert(0 == (flags & (unsigned)(~(H5C__READ_ONLY_FLAG | \
+                                        H5C__FLUSH_LAST_FLAG))));
+#endif /* H5_HAVE_PARALLEL */
+
     /* Check for invalid access request */
-    if(0 == (H5F_INTENT(f) & H5F_ACC_RDWR) && rw == H5AC_WRITE)
+    if((0 == (H5F_INTENT(f) & H5F_ACC_RDWR)) &&  (0 == (flags & H5C__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_CACHE, H5E_BADVALUE, NULL, "no write intent on file")
 
 #if H5AC__TRACE_FILE_ENABLED
-    /* For the protect call, only the addr and type id is really necessary
-     * in the trace file.  Include the size of the entry protected as a
-     * sanity check.  Also indicate whether the call was successful to
-     * catch occult errors.
+    /* For the protect call, only the addr, size, type id, and flags are 
+     * necessary in the trace file.  Also indicate whether the call was 
+     * successful to catch occult errors.
      */
-    if(NULL != (trace_file_ptr = H5C_get_trace_file_ptr(cache_ptr))) {
-
-	const char * rw_string;
-
-        if ( rw == H5AC_WRITE ) {
-
-	    rw_string = "H5AC_WRITE";
-
-	} else if ( rw == H5AC_READ ) {
-
-	    rw_string = "H5AC_READ";
-
-	} else {
-
-	    rw_string = "???";
-	}
-
-        sprintf(trace, "%s 0x%lx %d %s", FUNC, (unsigned long)addr,
-		(int)(type->id), rw_string);
-    }
+    if(NULL != (trace_file_ptr = H5C_get_trace_file_ptr(cache_ptr)))
+        sprintf(trace, "%s 0x%lx %d 0x%x", FUNC, (unsigned long)addr,
+		(int)(type->id), flags);
 #endif /* H5AC__TRACE_FILE_ENABLED */
 
-    if ( rw == H5AC_READ )
-	protect_flags |= H5C__READ_ONLY_FLAG;
-
-    if(NULL == (thing = H5C_protect(f, dxpl_id, H5AC_dxpl_id, type, addr, udata, protect_flags)))
-
+    if(NULL == (thing = H5C_protect(f, dxpl_id, type, addr, udata, flags)))
         HGOTO_ERROR(H5E_CACHE, H5E_CANTPROTECT, NULL, "H5C_protect() failed.")
 
 #if H5AC__TRACE_FILE_ENABLED
@@ -1262,11 +1170,10 @@ H5AC_resize_entry(void *thing, size_t new_size)
 {
     H5AC_info_t * entry_ptr = (H5AC_info_t *)thing;
     H5C_t *cache_ptr = entry_ptr->cache_ptr;
+    H5AC_aux_t *aux_ptr;
 
-    HDassert(cache_ptr);
-    HDassert(cache_ptr->magic == H5C__H5C_T_MAGIC);
-
-    if((!entry_ptr->is_dirty) && (NULL != cache_ptr->aux_ptr))
+    aux_ptr = H5C_get_aux_ptr(cache_ptr);
+    if((!entry_ptr->is_dirty) && (NULL != aux_ptr))
         if(H5AC__log_dirtied_entry(entry_ptr) < 0)
             HGOTO_ERROR(H5E_CACHE, H5E_CANTMARKDIRTY, FAIL, "can't log dirtied entry")
 }
@@ -1438,8 +1345,8 @@ H5AC_unprotect(H5F_t *f, hid_t dxpl_id, const H5AC_class_t *type, haddr_t addr,
     HDassert(f->shared);
     HDassert(f->shared->cache);
     HDassert(type);
-    HDassert(type->clear);
-    HDassert(type->flush);
+    HDassert(type->deserialize);
+    HDassert(type->image_len);
     HDassert(H5F_addr_defined(addr));
     HDassert(thing);
     HDassert( ((H5AC_info_t *)thing)->addr == addr );
@@ -1462,9 +1369,11 @@ H5AC_unprotect(H5F_t *f, hid_t dxpl_id, const H5AC_class_t *type, haddr_t addr,
      *  the entry.
      */
     if(dirtied && !deleted) {
+        hbool_t		curr_compressed = FALSE; /* dummy for call */
         size_t		curr_size = 0;
+        size_t		curr_compressed_size = 0; /* dummy for call */
 
-        if((type->size)(f, thing, &curr_size) < 0)
+        if((type->image_len)(thing, &curr_size, &curr_compressed, &curr_compressed_size) < 0)
             HGOTO_ERROR(H5E_CACHE, H5E_CANTGETSIZE, FAIL, "Can't get size of thing")
 
         if(((H5AC_info_t *)thing)->size != curr_size)
@@ -1472,7 +1381,7 @@ H5AC_unprotect(H5F_t *f, hid_t dxpl_id, const H5AC_class_t *type, haddr_t addr,
     } /* end if */
 
 #ifdef H5_HAVE_PARALLEL
-    if(NULL != (aux_ptr = (H5AC_aux_t *)f->shared->cache->aux_ptr)) {
+    if(NULL != (aux_ptr = H5C_get_aux_ptr(f->shared->cache))) {
         if(dirtied && ((H5AC_info_t *)thing)->is_dirty == FALSE)
             if(H5AC__log_dirtied_entry((H5AC_info_t *)thing) < 0)
                 HGOTO_ERROR(H5E_CACHE, H5E_CANTUNPROTECT, FAIL, "can't log dirtied entry")
@@ -1483,7 +1392,7 @@ H5AC_unprotect(H5F_t *f, hid_t dxpl_id, const H5AC_class_t *type, haddr_t addr,
     } /* end if */
 #endif /* H5_HAVE_PARALLEL */
 
-    if(H5C_unprotect(f, dxpl_id, H5AC_dxpl_id, type, addr, thing, flags) < 0)
+    if(H5C_unprotect(f, dxpl_id, addr, thing, flags) < 0)
         HGOTO_ERROR(H5E_CACHE, H5E_CANTUNPROTECT, FAIL, "H5C_unprotect() failed.")
 
 #ifdef H5_HAVE_PARALLEL
@@ -1502,78 +1411,6 @@ done:
     FUNC_LEAVE_NOAPI(ret_value)
 } /* H5AC_unprotect() */
 
-
-/*-------------------------------------------------------------------------
- * Function:    HA5C_set_sync_point_done_callback
- *
- * Purpose:     Set the value of the sync_point_done callback.  This 
- *		callback is used by the parallel test code to verify
- *		that the expected writes and only the expected writes
- *		take place during a sync point.
- *
- * Return:      Non-negative on success/Negative on failure
- *
- * Programmer:  John Mainzer
- *              5/9/10
- *
- *-------------------------------------------------------------------------
- */
-#ifdef H5_HAVE_PARALLEL
-herr_t
-H5AC_set_sync_point_done_callback(H5C_t * cache_ptr,
-    void (* sync_point_done)(int num_writes, haddr_t * written_entries_tbl))
-{
-    H5AC_aux_t * aux_ptr;
-
-    FUNC_ENTER_NOAPI_NOINIT_NOERR
-
-    /* Sanity checks */
-    HDassert(cache_ptr && (cache_ptr->magic == H5C__H5C_T_MAGIC));
-    aux_ptr = (H5AC_aux_t *)(cache_ptr->aux_ptr);
-    HDassert(aux_ptr != NULL);
-    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
-
-    aux_ptr->sync_point_done = sync_point_done;
-
-    FUNC_LEAVE_NOAPI(SUCCEED)
-} /* H5AC_set_sync_point_done_callback() */
-#endif /* H5_HAVE_PARALLEL */
-
-
-/*-------------------------------------------------------------------------
- * Function:    HA5C_set_write_done_callback
- *
- * Purpose:     Set the value of the write_done callback.  This callback
- *              is used to improve performance of the parallel test bed
- *              for the cache.
- *
- * Return:      Non-negative on success/Negative on failure
- *
- * Programmer:  John Mainzer
- *              5/11/06
- *
- *-------------------------------------------------------------------------
- */
-#ifdef H5_HAVE_PARALLEL
-herr_t
-H5AC_set_write_done_callback(H5C_t * cache_ptr, void (* write_done)(void))
-{
-    H5AC_aux_t * aux_ptr;
-
-    FUNC_ENTER_NOAPI_NOINIT_NOERR
-
-    /* Sanity checks */
-    HDassert(cache_ptr && (cache_ptr->magic == H5C__H5C_T_MAGIC));
-    aux_ptr = (H5AC_aux_t *)(cache_ptr->aux_ptr);
-    HDassert( aux_ptr != NULL );
-    HDassert( aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC );
-
-    aux_ptr->write_done = write_done;
-
-    FUNC_LEAVE_NOAPI(SUCCEED)
-} /* H5AC_set_write_done_callback() */
-#endif /* H5_HAVE_PARALLEL */
-
 #ifndef NDEBUG  /* debugging functions */
 
 /*-------------------------------------------------------------------------
@@ -1662,14 +1499,18 @@ H5AC_get_cache_auto_resize_config(const H5AC_t *cache_ptr,
     FUNC_ENTER_NOAPI(FAIL)
 
     /* Check args */
-    if((cache_ptr == NULL) ||
+    if((cache_ptr == NULL) || (config_ptr == NULL) ||
+            (config_ptr->version != H5AC__CURR_CACHE_CONFIG_VERSION))
+        HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Bad cache_ptr or config_ptr on entry.")
 #ifdef H5_HAVE_PARALLEL
-             ((cache_ptr->aux_ptr != NULL) &&
-               (((H5AC_aux_t *)(cache_ptr->aux_ptr))->magic != H5AC__H5AC_AUX_T_MAGIC))
-             ||
+{
+    H5AC_aux_t *aux_ptr;
+
+    aux_ptr = H5C_get_aux_ptr(cache_ptr);
+    if((aux_ptr != NULL) && (aux_ptr->magic != H5AC__H5AC_AUX_T_MAGIC))
+        HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Bad aux_ptr on entry.")
+}
 #endif /* H5_HAVE_PARALLEL */
-             (config_ptr == NULL) || (config_ptr->version != H5AC__CURR_CACHE_CONFIG_VERSION))
-        HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Bad cache_ptr or config_ptr on entry.")
 
     /* Retrieve the configuration */
     if(H5C_get_cache_auto_resize_config((const H5C_t *)cache_ptr, &internal_config) < 0)
@@ -1709,9 +1550,12 @@ H5AC_get_cache_auto_resize_config(const H5AC_t *cache_ptr,
     config_ptr->apply_empty_reserve    = internal_config.apply_empty_reserve;
     config_ptr->empty_reserve          = internal_config.empty_reserve;
 #ifdef H5_HAVE_PARALLEL
-    if(cache_ptr->aux_ptr != NULL) {
-        config_ptr->dirty_bytes_threshold = ((H5AC_aux_t *)(cache_ptr->aux_ptr))->dirty_bytes_threshold;
-	config_ptr->metadata_write_strategy = ((H5AC_aux_t *)(cache_ptr->aux_ptr))->metadata_write_strategy;
+{
+    H5AC_aux_t *aux_ptr;
+
+    if(NULL != (aux_ptr = H5C_get_aux_ptr(cache_ptr))) {
+        config_ptr->dirty_bytes_threshold = aux_ptr->dirty_bytes_threshold;
+	config_ptr->metadata_write_strategy = aux_ptr->metadata_write_strategy;
     } /* end if */
     else {
 #endif /* H5_HAVE_PARALLEL */
@@ -1719,6 +1563,7 @@ H5AC_get_cache_auto_resize_config(const H5AC_t *cache_ptr,
 	config_ptr->metadata_write_strategy = H5AC__DEFAULT_METADATA_WRITE_STRATEGY;
 #ifdef H5_HAVE_PARALLEL
     } /* end else */
+}
 #endif /* H5_HAVE_PARALLEL */
 
 done:
@@ -1844,13 +1689,17 @@ H5AC_set_cache_auto_resize_config(H5AC_t *cache_ptr, H5AC_cache_config_t *config
         trace_config = *config_ptr;
 #endif /* H5AC__TRACE_FILE_ENABLED */
 
-    if((cache_ptr == NULL)
+    if(cache_ptr == NULL)
+        HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "bad cache_ptr on entry.")
 #ifdef H5_HAVE_PARALLEL
-            || ((cache_ptr->aux_ptr != NULL) &&
-                (((H5AC_aux_t *)(cache_ptr->aux_ptr))->magic != H5AC__H5AC_AUX_T_MAGIC))
+{
+    H5AC_aux_t *aux_ptr;
+
+    aux_ptr = H5C_get_aux_ptr(cache_ptr);
+    if((aux_ptr != NULL) && (aux_ptr->magic != H5AC__H5AC_AUX_T_MAGIC))
+        HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "bad aux_ptr on entry.")
+}
 #endif /* H5_HAVE_PARALLEL */
-            )
-        HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "bad cache_ptr on entry.")
 
     /* Validate external configuration */
     if(H5AC_validate_config(config_ptr) != SUCCEED)
@@ -1885,12 +1734,16 @@ H5AC_set_cache_auto_resize_config(H5AC_t *cache_ptr, H5AC_cache_config_t *config
         HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "H5C_set_evictions_enabled() failed.")
 
 #ifdef H5_HAVE_PARALLEL
+{
+    H5AC_aux_t *aux_ptr;
+
     /* Set parallel configuration values */
     /* (Which are only held in the H5AC layer -QAK) */
-    if(cache_ptr->aux_ptr != NULL) {
-        ((H5AC_aux_t *)(cache_ptr->aux_ptr))->dirty_bytes_threshold = config_ptr->dirty_bytes_threshold;
-        ((H5AC_aux_t *)(cache_ptr->aux_ptr))->metadata_write_strategy = config_ptr->metadata_write_strategy;
+    if(NULL != (aux_ptr = H5C_get_aux_ptr(cache_ptr))) {
+        aux_ptr->dirty_bytes_threshold = config_ptr->dirty_bytes_threshold;
+        aux_ptr->metadata_write_strategy = config_ptr->metadata_write_strategy;
     } /* end if */
+}
 #endif /* H5_HAVE_PARALLEL */
 
 done:
@@ -2081,9 +1934,6 @@ H5AC_open_trace_file(H5AC_t *cache_ptr, const char *trace_file_name)
 {
     char     file_name[H5AC__MAX_TRACE_FILE_NAME_LEN + H5C__PREFIX_LEN + 2];
     FILE *   file_ptr = NULL;
-#ifdef H5_HAVE_PARALLEL
-    H5AC_aux_t * aux_ptr = NULL;
-#endif /* H5_HAVE_PARALLEL */
     herr_t   ret_value = SUCCEED;    /* Return value */
 
     FUNC_ENTER_NOAPI(FAIL)
@@ -2101,8 +1951,11 @@ H5AC_open_trace_file(H5AC_t *cache_ptr, const char *trace_file_name)
         HGOTO_ERROR(H5E_CACHE, H5E_FILEOPEN, FAIL, "trace file already open.")
 
 #ifdef H5_HAVE_PARALLEL
-    aux_ptr = (H5AC_aux_t *)(cache_ptr->aux_ptr);
-    if(cache_ptr->aux_ptr == NULL)
+{
+    H5AC_aux_t * aux_ptr;
+
+    aux_ptr = H5C_get_aux_ptr(cache_ptr);
+    if(aux_ptr == NULL)
         sprintf(file_name, "%s", trace_file_name);
     else {
 	if(aux_ptr->magic != H5AC__H5AC_AUX_T_MAGIC)
@@ -2113,6 +1966,7 @@ H5AC_open_trace_file(H5AC_t *cache_ptr, const char *trace_file_name)
 
     if(HDstrlen(file_name) > H5AC__MAX_TRACE_FILE_NAME_LEN + H5C__PREFIX_LEN + 1)
         HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "cooked trace file name too long.")
+}
 #else /* H5_HAVE_PARALLEL */
     HDsnprintf(file_name, (size_t)(H5AC__MAX_TRACE_FILE_NAME_LEN + H5C__PREFIX_LEN + 1), 
                "%s", trace_file_name);
@@ -2131,64 +1985,6 @@ done:
 } /* H5AC_open_trace_file() */
 
 
-/*-------------------------------------------------------------------------
- * Function:    H5AC_add_candidate()
- *
- * Purpose:     Add the supplied metadata entry address to the candidate
- *		list.  Verify that each entry added does not appear in 
- *		the list prior to its insertion.
- *
- *		This function is intended for used in constructing list
- *		of entried to be flushed during sync points.  It shouldn't
- *		be called anywhere else.
- *
- * Return:      Non-negative on success/Negative on failure
- *
- * Programmer:  John Mainzer
- *              3/17/10
- *
- *-------------------------------------------------------------------------
- */
-#ifdef H5_HAVE_PARALLEL
-herr_t
-H5AC_add_candidate(H5AC_t * cache_ptr, haddr_t addr)
-{
-    H5AC_aux_t         * aux_ptr;
-    H5AC_slist_entry_t * slist_entry_ptr = NULL;
-    herr_t               ret_value = SUCCEED;    /* Return value */
-
-    FUNC_ENTER_NOAPI(FAIL)
-
-    /* Sanity checks */
-    HDassert(cache_ptr != NULL);
-    HDassert(cache_ptr->magic == H5C__H5C_T_MAGIC);
-    aux_ptr = (H5AC_aux_t *)(cache_ptr->aux_ptr);
-    HDassert(aux_ptr != NULL);
-    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
-    HDassert(aux_ptr->metadata_write_strategy == H5AC_METADATA_WRITE_STRATEGY__DISTRIBUTED);
-    HDassert(aux_ptr->candidate_slist_ptr != NULL);
-
-    /* Construct an entry for the supplied address, and insert
-     * it into the candidate slist.
-     */
-    if(NULL == (slist_entry_ptr = H5FL_MALLOC(H5AC_slist_entry_t)))
-        HGOTO_ERROR(H5E_CACHE, H5E_CANTALLOC, FAIL, "Can't allocate candidate slist entry")
-    slist_entry_ptr->addr  = addr;
-
-    if(H5SL_insert(aux_ptr->candidate_slist_ptr, slist_entry_ptr, &(slist_entry_ptr->addr)) < 0)
-        HGOTO_ERROR(H5E_CACHE, H5E_CANTINSERT, FAIL, "can't insert entry into dirty entry slist")
-
-done:
-    /* Clean up on error */
-    if(ret_value < 0)
-        if(slist_entry_ptr)
-            slist_entry_ptr = H5FL_FREE(H5AC_slist_entry_t, slist_entry_ptr);
-
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* H5AC_add_candidate() */
-#endif /* H5_HAVE_PARALLEL */
-
-
 /*************************************************************************/
 /*************************** Debugging Functions: ************************/
 /*************************************************************************/
@@ -2300,236 +2096,6 @@ done:
 /**************************** Private Functions: *************************/
 /*************************************************************************/
 
-/*-------------------------------------------------------------------------
- *
- * Function:    H5AC__broadcast_candidate_list()
- *
- * Purpose:     Broadcast the contents of the process 0 candidate entry
- *		slist.  In passing, also remove all entries from said
- *		list.  As the application of this will be handled by 
- *		the same functions on all processes, construct and 
- *		return a copy of the list in the same format as that
- *		received by the other processes.  Note that if this
- *		copy is returned in *haddr_buf_ptr_ptr, the caller 
- *		must free it.
- *
- *		This function must only be called by the process with
- *		MPI_rank 0.
- *
- *		Return SUCCEED on success, and FAIL on failure.
- *
- * Return:      Non-negative on success/Negative on failure.
- *
- * Programmer:  John Mainzer, 7/1/05
- *
- *-------------------------------------------------------------------------
- */
-#ifdef H5_HAVE_PARALLEL
-static herr_t
-H5AC__broadcast_candidate_list(H5AC_t *cache_ptr, int *num_entries_ptr,
-    haddr_t **haddr_buf_ptr_ptr)
-{
-    H5AC_aux_t         * aux_ptr = NULL;
-    haddr_t            * haddr_buf_ptr = NULL;
-    int                  mpi_result;
-    int			 num_entries;
-    herr_t               ret_value = SUCCEED;    /* Return value */
-
-    FUNC_ENTER_STATIC
-
-    /* Sanity checks */
-    HDassert(cache_ptr != NULL);
-    HDassert(cache_ptr->magic == H5C__H5C_T_MAGIC);
-    aux_ptr = (H5AC_aux_t *)(cache_ptr->aux_ptr);
-    HDassert(aux_ptr != NULL);
-    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
-    HDassert(aux_ptr->mpi_rank == 0);
-    HDassert(aux_ptr->metadata_write_strategy == H5AC_METADATA_WRITE_STRATEGY__DISTRIBUTED);
-    HDassert(aux_ptr->candidate_slist_ptr != NULL);
-    HDassert(num_entries_ptr != NULL);
-    HDassert(*num_entries_ptr == 0);
-    HDassert(haddr_buf_ptr_ptr != NULL);
-    HDassert(*haddr_buf_ptr_ptr == NULL);
-
-    /* First broadcast the number of entries in the list so that the
-     * receivers can set up buffers to receive them.  If there aren't
-     * any, we are done.
-     */
-    num_entries = (int)H5SL_count(aux_ptr->candidate_slist_ptr);
-    if(MPI_SUCCESS != (mpi_result = MPI_Bcast(&num_entries, 1, MPI_INT, 0, aux_ptr->mpi_comm)))
-        HMPI_GOTO_ERROR(FAIL, "MPI_Bcast failed", mpi_result)
-
-    if(num_entries > 0) {
-        size_t		 buf_size = 0;
-        int		 chk_num_entries = 0;
-
-        /* convert the candidate list into the format we
-         * are used to receiving from process 0, and also load it 
-         * into a buffer for transmission.
-         */
-        if(H5AC__copy_candidate_list_to_buffer(cache_ptr, &chk_num_entries, &haddr_buf_ptr) < 0)
-            HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "Can't construct candidate buffer.")
-        HDassert(chk_num_entries == num_entries);
-        HDassert(haddr_buf_ptr != NULL);
-
-        /* Now broadcast the list of candidate entries */
-        buf_size = sizeof(haddr_t) * (size_t)num_entries;
-        if(MPI_SUCCESS != (mpi_result = MPI_Bcast((void *)haddr_buf_ptr, (int)buf_size, MPI_BYTE, 0, aux_ptr->mpi_comm)))
-            HMPI_GOTO_ERROR(FAIL, "MPI_Bcast failed", mpi_result)
-    } /* end if */
-
-    /* Pass the number of entries and the buffer pointer 
-     * back to the caller.  Do this so that we can use the same code
-     * to apply the candidate list to all the processes.
-     */
-    *num_entries_ptr = num_entries;
-    *haddr_buf_ptr_ptr = haddr_buf_ptr;
-
-done:
-    if(ret_value < 0)
-        if(haddr_buf_ptr)
-            haddr_buf_ptr = (haddr_t *)H5MM_xfree((void *)haddr_buf_ptr);
-
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* H5AC__broadcast_candidate_list() */
-#endif /* H5_HAVE_PARALLEL */
-
-
-/*-------------------------------------------------------------------------
- *
- * Function:    H5AC__broadcast_clean_list_cb()
- *
- * Purpose:     Skip list callback for building array of addresses for
- *              broadcasting the clean list.
- *
- * Return:      Non-negative on success/Negative on failure.
- *
- * Programmer:  Quincey Koziol, 6/12/15
- *
- *-------------------------------------------------------------------------
- */
-#ifdef H5_HAVE_PARALLEL
-static herr_t
-H5AC__broadcast_clean_list_cb(void *_item, void H5_ATTR_UNUSED *_key,
-    void *_udata)
-{
-    H5AC_slist_entry_t    * slist_entry_ptr = (H5AC_slist_entry_t *)_item;  /* Address of item */
-    H5AC_addr_list_ud_t   * udata = (H5AC_addr_list_ud_t *)_udata;      /* Context for callback */
-    haddr_t		    addr;
-
-    FUNC_ENTER_STATIC_NOERR
-
-    /* Sanity checks */
-    HDassert(slist_entry_ptr);
-    HDassert(udata);
-
-    /* Store the entry's address in the buffer */
-    addr = slist_entry_ptr->addr;
-    udata->addr_buf_ptr[udata->i] = addr;
-    udata->i++;
-
-    /* now release the entry */
-    slist_entry_ptr = H5FL_FREE(H5AC_slist_entry_t, slist_entry_ptr);
-
-    /* and also remove the matching entry from the dirtied list
-     * if it exists.
-     */
-    if(NULL != (slist_entry_ptr = (H5AC_slist_entry_t *)H5SL_remove(udata->aux_ptr->d_slist_ptr, (void *)(&addr))))
-        slist_entry_ptr = H5FL_FREE(H5AC_slist_entry_t, slist_entry_ptr);
-
-    FUNC_LEAVE_NOAPI(SUCCEED)
-} /* H5AC__broadcast_clean_list_cb() */
-#endif /* H5_HAVE_PARALLEL */
-
-
-/*-------------------------------------------------------------------------
- *
- * Function:    H5AC__broadcast_clean_list()
- *
- * Purpose:     Broadcast the contents of the process 0 cleaned entry
- *		slist.  In passing, also remove all entries from said
- *		list, and also remove any matching entries from the dirtied
- *		slist.
- *
- *		This function must only be called by the process with
- *		MPI_rank 0.
- *
- *		Return SUCCEED on success, and FAIL on failure.
- *
- * Return:      Non-negative on success/Negative on failure.
- *
- * Programmer:  John Mainzer, 7/1/05
- *
- *-------------------------------------------------------------------------
- */
-#ifdef H5_HAVE_PARALLEL
-static herr_t
-H5AC__broadcast_clean_list(H5AC_t * cache_ptr)
-{
-    haddr_t	       * addr_buf_ptr = NULL;
-    H5AC_aux_t         * aux_ptr;
-    int                  mpi_result;
-    int			 num_entries = 0;
-    herr_t               ret_value = SUCCEED;    /* Return value */
-
-    FUNC_ENTER_STATIC
-
-    /* Sanity checks */
-    HDassert(cache_ptr != NULL);
-    HDassert(cache_ptr->magic == H5C__H5C_T_MAGIC);
-    aux_ptr = (H5AC_aux_t *)cache_ptr->aux_ptr;
-    HDassert(aux_ptr != NULL);
-    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
-    HDassert(aux_ptr->mpi_rank == 0);
-    HDassert(aux_ptr->c_slist_ptr != NULL);
-
-    /* First broadcast the number of entries in the list so that the
-     * receives can set up a buffer to receive them.  If there aren't
-     * any, we are done.
-     */
-    num_entries = (int)H5SL_count(aux_ptr->c_slist_ptr);
-    if(MPI_SUCCESS != (mpi_result = MPI_Bcast(&num_entries, 1, MPI_INT, 0, aux_ptr->mpi_comm)))
-        HMPI_GOTO_ERROR(FAIL, "MPI_Bcast failed", mpi_result)
-
-    if(num_entries > 0) {
-        H5AC_addr_list_ud_t udata;
-        size_t		 buf_size;
-
-        /* allocate a buffer to store the list of entry base addresses in */
-        buf_size = sizeof(haddr_t) * (size_t)num_entries;
-        if(NULL == (addr_buf_ptr = (haddr_t *)H5MM_malloc(buf_size)))
-            HGOTO_ERROR(H5E_CACHE, H5E_CANTALLOC, FAIL, "memory allocation failed for addr buffer")
-
-        /* Set up user data for callback */
-        udata.aux_ptr = aux_ptr;
-        udata.addr_buf_ptr = addr_buf_ptr;
-        udata.i = 0;
-
-        /* Free all the clean list entries, building the address list in the callback */
-        /* (Callback also removes the matching entries from the dirtied list) */
-        if(H5SL_free(aux_ptr->c_slist_ptr, H5AC__broadcast_clean_list_cb, &udata) < 0)
-            HGOTO_ERROR(H5E_CACHE, H5E_CANTFREE, FAIL, "Can't build address list for clean entries")
-
-        /* Now broadcast the list of cleaned entries */
-        if(MPI_SUCCESS != (mpi_result = MPI_Bcast((void *)addr_buf_ptr, (int)buf_size, MPI_BYTE, 0, aux_ptr->mpi_comm)))
-            HMPI_GOTO_ERROR(FAIL, "MPI_Bcast failed", mpi_result)
-    } /* end if */
-
-    /* if it is defined, call the sync point done callback.  Note
-     * that this callback is defined purely for testing purposes,
-     * and should be undefined under normal operating circumstances.
-     */
-    if(aux_ptr->sync_point_done)
-        (aux_ptr->sync_point_done)(num_entries, addr_buf_ptr);
-
-done:
-    if(addr_buf_ptr)
-        addr_buf_ptr = (haddr_t *)H5MM_xfree((void *)addr_buf_ptr);
-
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* H5AC__broadcast_clean_list() */
-#endif /* H5_HAVE_PARALLEL */
-
 
 /*-------------------------------------------------------------------------
  *
@@ -2569,7 +2135,7 @@ H5_ATTR_UNUSED
     HDassert(f != NULL);
     HDassert(f->shared != NULL);
     HDassert(f->shared->cache != NULL);
-    aux_ptr = (H5AC_aux_t *)(f->shared->cache->aux_ptr);
+    aux_ptr = H5C_get_aux_ptr(f->shared->cache);
     if(aux_ptr != NULL) {
         HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
 
@@ -2587,202 +2153,6 @@ H5_ATTR_UNUSED
 
 
 /*-------------------------------------------------------------------------
- * Function:    H5AC__construct_candidate_list()
- *
- * Purpose:     In the parallel case when the metadata_write_strategy is 
- *		H5AC_METADATA_WRITE_STRATEGY__DISTRIBUTED, process 0 uses
- *		this function to construct the list of cache entries to 
- *		be flushed.  This list is then propagated to the other 
- *		caches, and then flushed in a distributed fashion.
- *
- *		The sync_point_op parameter is used to determine the extent
- *		of the flush.
- *
- * Return:      Non-negative on success/Negative on failure
- *
- * Programmer:  John Mainzer
- *              3/17/10
- *
- *-------------------------------------------------------------------------
- */
-#ifdef H5_HAVE_PARALLEL
-static herr_t
-H5AC__construct_candidate_list(H5AC_t *cache_ptr, H5AC_aux_t *aux_ptr,
-    int sync_point_op)
-{
-    herr_t ret_value = SUCCEED;    /* Return value */
-
-    FUNC_ENTER_STATIC
-
-    /* Sanity checks */
-    HDassert(cache_ptr != NULL);
-    HDassert(cache_ptr->magic == H5C__H5C_T_MAGIC);
-    HDassert(aux_ptr != NULL);
-    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
-    HDassert(aux_ptr->metadata_write_strategy == H5AC_METADATA_WRITE_STRATEGY__DISTRIBUTED);
-    HDassert((sync_point_op == H5AC_SYNC_POINT_OP__FLUSH_CACHE) || (aux_ptr->mpi_rank == 0));
-    HDassert(aux_ptr->d_slist_ptr != NULL);
-    HDassert(aux_ptr->c_slist_ptr != NULL);
-    HDassert(H5SL_count(aux_ptr->c_slist_ptr) == 0);
-    HDassert(aux_ptr->candidate_slist_ptr != NULL);
-    HDassert(H5SL_count(aux_ptr->candidate_slist_ptr) == 0);
-    HDassert((sync_point_op == H5AC_SYNC_POINT_OP__FLUSH_TO_MIN_CLEAN) || (sync_point_op == H5AC_SYNC_POINT_OP__FLUSH_CACHE));
-
-    switch(sync_point_op) {
-	case H5AC_SYNC_POINT_OP__FLUSH_TO_MIN_CLEAN:
-            if(H5C_construct_candidate_list__min_clean((H5C_t *)cache_ptr) < 0)
-		HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "H5C_construct_candidate_list__min_clean() failed.")
-	    break;
-
-	case H5AC_SYNC_POINT_OP__FLUSH_CACHE:
-            if(H5C_construct_candidate_list__clean_cache((H5C_t *)cache_ptr) < 0)
-		HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "H5C_construct_candidate_list__clean_cache() failed.")
-	    break;
-
-        default:
-	    HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "unknown sync point operation.")
-	    break;
-    } /* end switch */
-
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* H5AC__construct_candidate_list() */
-#endif /* H5_HAVE_PARALLEL */
-
-
-/*-------------------------------------------------------------------------
- *
- * Function:    H5AC__copy_candidate_list_to_buffer_cb
- *
- * Purpose:     Skip list callback for building array of addresses for
- *              broadcasting the candidate list.
- *
- * Return:	Return SUCCEED on success, and FAIL on failure.
- *
- * Programmer:  Quincey Koziol, 6/12/15
- *
- *-------------------------------------------------------------------------
- */
-#ifdef H5_HAVE_PARALLEL
-static herr_t
-H5AC__copy_candidate_list_to_buffer_cb(void *_item, void H5_ATTR_UNUSED *_key,
-    void *_udata)
-{
-    H5AC_slist_entry_t    * slist_entry_ptr = (H5AC_slist_entry_t *)_item;  /* Address of item */
-    H5AC_addr_list_ud_t   * udata = (H5AC_addr_list_ud_t *)_udata;      /* Context for callback */
-
-    FUNC_ENTER_STATIC_NOERR
-
-    /* Sanity checks */
-    HDassert(slist_entry_ptr);
-    HDassert(udata);
-
-    /* Store the entry's address in the buffer */
-    udata->addr_buf_ptr[udata->i] = slist_entry_ptr->addr;
-    udata->i++;
-
-    /* now release the entry */
-    slist_entry_ptr = H5FL_FREE(H5AC_slist_entry_t, slist_entry_ptr);
-
-    FUNC_LEAVE_NOAPI(SUCCEED)
-} /* H5AC__copy_candidate_list_to_buffer_cb() */
-#endif /* H5_HAVE_PARALLEL */
-
-
-/*-------------------------------------------------------------------------
- *
- * Function:    H5AC__copy_candidate_list_to_buffer
- *
- * Purpose:     Allocate buffer(s) and copy the contents of the candidate
- *		entry slist into it (them).  In passing, remove all 
- *		entries from the candidate slist.  Note that the 
- *		candidate slist must not be empty.
- *
- *		If MPI_Offset_buf_ptr_ptr is not NULL, allocate a buffer
- *		of MPI_Offset, copy the contents of the candidate
- *		entry list into it with the appropriate conversions, 
- *		and return the base address of the buffer in 
- *		*MPI_Offset_buf_ptr.  Note that this is the buffer
- *		used by process 0 to transmit the list of entries to 
- *		be flushed to all other processes (in this file group).
- *
- *		Similarly, allocate a buffer of haddr_t, load the contents
- *		of the candidate list into this buffer, and return its 
- *		base address in *haddr_buf_ptr_ptr.  Note that this 
- *		latter buffer is constructed unconditionally.  
- *
- *		In passing, also remove all entries from the candidate
- *		entry slist.
- *
- * Return:	Return SUCCEED on success, and FAIL on failure.
- *
- * Programmer:  John Mainzer, 4/19/10
- *
- *-------------------------------------------------------------------------
- */
-#ifdef H5_HAVE_PARALLEL
-static herr_t
-H5AC__copy_candidate_list_to_buffer(const H5AC_t *cache_ptr, int *num_entries_ptr,
-    haddr_t **haddr_buf_ptr_ptr)
-{
-    H5AC_aux_t         * aux_ptr = NULL;
-    H5AC_addr_list_ud_t  udata;
-    haddr_t            * haddr_buf_ptr = NULL;
-    size_t		 buf_size;
-    int			 num_entries = 0;
-    herr_t               ret_value = SUCCEED;    /* Return value */
-
-    FUNC_ENTER_STATIC
-
-    /* Sanity checks */
-    HDassert(cache_ptr != NULL);
-    HDassert(cache_ptr->magic == H5C__H5C_T_MAGIC);
-    aux_ptr = (H5AC_aux_t *)(cache_ptr->aux_ptr);
-    HDassert(aux_ptr != NULL);
-    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
-    HDassert(aux_ptr->metadata_write_strategy == H5AC_METADATA_WRITE_STRATEGY__DISTRIBUTED);
-    HDassert(aux_ptr->candidate_slist_ptr != NULL);
-    HDassert(H5SL_count(aux_ptr->candidate_slist_ptr) > 0);
-    HDassert(num_entries_ptr != NULL);
-    HDassert(*num_entries_ptr == 0);
-    HDassert(haddr_buf_ptr_ptr != NULL);
-    HDassert(*haddr_buf_ptr_ptr == NULL);
-
-    num_entries = (int)H5SL_count(aux_ptr->candidate_slist_ptr);
-
-    /* allocate a buffer(s) to store the list of candidate entry 
-     * base addresses in 
-     */
-    buf_size = sizeof(haddr_t) * (size_t)num_entries;
-    if(NULL == (haddr_buf_ptr = (haddr_t *)H5MM_malloc(buf_size)))
-        HGOTO_ERROR(H5E_CACHE, H5E_CANTALLOC, FAIL, "memory allocation failed for haddr buffer")
-
-    /* Set up user data for callback */
-    udata.aux_ptr = aux_ptr;
-    udata.addr_buf_ptr = haddr_buf_ptr;
-    udata.i = 0;
-
-    /* Free all the candidate list entries, building the address list in the callback */
-    if(H5SL_free(aux_ptr->candidate_slist_ptr, H5AC__copy_candidate_list_to_buffer_cb, &udata) < 0)
-        HGOTO_ERROR(H5E_CACHE, H5E_CANTFREE, FAIL, "Can't build address list for candidate entries")
-
-    /* Pass the number of entries and the buffer pointer 
-     * back to the caller.
-     */
-    *num_entries_ptr = num_entries;
-    *haddr_buf_ptr_ptr = haddr_buf_ptr;
-
-done:
-    if(ret_value < 0)
-        if(haddr_buf_ptr)
-            haddr_buf_ptr = (haddr_t *)H5MM_xfree((void *)haddr_buf_ptr);
-
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* H5AC__copy_candidate_list_to_buffer() */
-#endif /* H5_HAVE_PARALLEL */
-
-
-/*-------------------------------------------------------------------------
  * Function:    H5AC__ext_config_2_int_config()
  *
  * Purpose:     Utility function to translate an instance of
@@ -2848,1630 +2218,6 @@ done:
 } /* H5AC__ext_config_2_int_config() */
 
 
-/*-------------------------------------------------------------------------
- *
- * Function:    H5AC__log_deleted_entry()
- *
- * Purpose:     Log an entry which has been deleted.
- *
- *		Only called for mpi_rank 0. We must make sure that the entry
- *              doesn't appear in the cleaned or dirty entry lists.
- *
- *		Return SUCCEED on success, and FAIL on failure.
- *
- * Return:      Non-negative on success/Negative on failure.
- *
- * Programmer:  John Mainzer, 6/29/05
- *
- *-------------------------------------------------------------------------
- */
-#ifdef H5_HAVE_PARALLEL
-static herr_t
-H5AC__log_deleted_entry(const H5AC_info_t *entry_ptr)
-{
-    H5AC_t             * cache_ptr;
-    H5AC_aux_t         * aux_ptr;
-    H5AC_slist_entry_t * slist_entry_ptr = NULL;
-    haddr_t              addr;
-
-    FUNC_ENTER_STATIC_NOERR
-
-    /* Sanity checks */
-    HDassert(entry_ptr);
-    addr = entry_ptr->addr;
-    cache_ptr = entry_ptr->cache_ptr;
-    HDassert(cache_ptr != NULL);
-    HDassert(cache_ptr->magic == H5C__H5C_T_MAGIC);
-    aux_ptr = (H5AC_aux_t *)(cache_ptr->aux_ptr);
-    HDassert(aux_ptr != NULL);
-    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
-    HDassert(aux_ptr->mpi_rank == 0);
-    HDassert(aux_ptr->d_slist_ptr != NULL);
-    HDassert(aux_ptr->c_slist_ptr != NULL);
-
-    /* if the entry appears in the dirtied entry slist, remove it. */
-    if(NULL != (slist_entry_ptr = (H5AC_slist_entry_t *)H5SL_remove(aux_ptr->d_slist_ptr, (void *)(&addr))))
-        slist_entry_ptr = H5FL_FREE(H5AC_slist_entry_t, slist_entry_ptr);
-
-    /* if the entry appears in the cleaned entry slist, remove it. */
-    if(NULL != (slist_entry_ptr = (H5AC_slist_entry_t *)H5SL_remove(aux_ptr->c_slist_ptr, (void *)(&addr))))
-        slist_entry_ptr = H5FL_FREE(H5AC_slist_entry_t, slist_entry_ptr);
-
-    FUNC_LEAVE_NOAPI(SUCCEED)
-} /* H5AC__log_deleted_entry() */
-#endif /* H5_HAVE_PARALLEL */
-
-
-/*-------------------------------------------------------------------------
- *
- * Function:    H5AC__log_dirtied_entry()
- *
- * Purpose:     Update the dirty_bytes count for a newly dirtied entry.
- *
- *		If mpi_rank isn't 0, this simply means adding the size
- *		of the entries to the dirty_bytes count.
- *
- *		If mpi_rank is 0, we must first check to see if the entry
- *		appears in the dirty entries slist.  If it is, do nothing.
- *		If it isn't, add the size to th dirty_bytes count, add the
- *		entry to the dirty entries slist, and remove it from the
- *		cleaned list (if it is present there).
- *
- *		Return SUCCEED on success, and FAIL on failure.
- *
- * Return:      Non-negative on success/Negative on failure.
- *
- * Programmer:  John Mainzer, 6/29/05
- *
- *-------------------------------------------------------------------------
- */
-#ifdef H5_HAVE_PARALLEL
-static herr_t
-H5AC__log_dirtied_entry(const H5AC_info_t *entry_ptr)
-{
-    H5AC_t             * cache_ptr;
-    H5AC_aux_t         * aux_ptr;
-    herr_t               ret_value = SUCCEED;    /* Return value */
-
-    FUNC_ENTER_STATIC
-
-    /* Sanity checks */
-    HDassert(entry_ptr);
-    HDassert(entry_ptr->is_dirty == FALSE);
-    cache_ptr = entry_ptr->cache_ptr;
-    HDassert(cache_ptr != NULL);
-    HDassert(cache_ptr->magic == H5C__H5C_T_MAGIC);
-    aux_ptr = (H5AC_aux_t *)(cache_ptr->aux_ptr);
-    HDassert(aux_ptr != NULL);
-    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
-
-    if(aux_ptr->mpi_rank == 0) {
-        H5AC_slist_entry_t *slist_entry_ptr;
-        haddr_t addr = entry_ptr->addr;
-
-        /* Sanity checks */
-        HDassert(aux_ptr->d_slist_ptr != NULL);
-        HDassert(aux_ptr->c_slist_ptr != NULL);
-
-        if(NULL == H5SL_search(aux_ptr->d_slist_ptr, (void *)(&addr))) {
-            /* insert the address of the entry in the dirty entry list, and
-             * add its size to the dirty_bytes count.
-             */
-            if(NULL == (slist_entry_ptr = H5FL_MALLOC(H5AC_slist_entry_t)))
-                HGOTO_ERROR(H5E_CACHE, H5E_CANTALLOC, FAIL, "Can't allocate dirty slist entry .")
-            slist_entry_ptr->addr  = addr;
-
-            if(H5SL_insert(aux_ptr->d_slist_ptr, slist_entry_ptr, &(slist_entry_ptr->addr)) < 0)
-                HGOTO_ERROR(H5E_CACHE, H5E_CANTINSERT, FAIL, "can't insert entry into dirty entry slist.")
-
-            aux_ptr->dirty_bytes += entry_ptr->size;
-#if H5AC_DEBUG_DIRTY_BYTES_CREATION
-	    aux_ptr->unprotect_dirty_bytes += entry_ptr->size;
-	    aux_ptr->unprotect_dirty_bytes_updates += 1;
-#endif /* H5AC_DEBUG_DIRTY_BYTES_CREATION */
-        } /* end if */
-
-        /* the entry is dirty.  If it exists on the cleaned entries list,
-         * remove it.
-         */
-        if(NULL != (slist_entry_ptr = (H5AC_slist_entry_t *)H5SL_remove(aux_ptr->c_slist_ptr, (void *)(&addr))))
-            slist_entry_ptr = H5FL_FREE(H5AC_slist_entry_t, slist_entry_ptr);
-    } /* end if */
-    else {
-        aux_ptr->dirty_bytes += entry_ptr->size;
-#if H5AC_DEBUG_DIRTY_BYTES_CREATION
-        aux_ptr->unprotect_dirty_bytes += entry_size;
-        aux_ptr->unprotect_dirty_bytes_updates += 1;
-#endif /* H5AC_DEBUG_DIRTY_BYTES_CREATION */
-    } /* end else */
-
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* H5AC__log_dirtied_entry() */
-#endif /* H5_HAVE_PARALLEL */
-
-
-/*-------------------------------------------------------------------------
- *
- * Function:    H5AC__log_flushed_entry()
- *
- * Purpose:     Update the clean entry slist for the flush of an entry --
- *		specifically, if the entry has been cleared, remove it
- * 		from both the cleaned and dirtied lists if it is present.
- *		Otherwise, if the entry was dirty, insert the indicated
- *		entry address in the clean slist if it isn't there already.
- *
- *		This function is only used in PHDF5, and should only
- *		be called for the process with mpi rank 0.
- *
- *		Return SUCCEED on success, and FAIL on failure.
- *
- * Return:      Non-negative on success/Negative on failure.
- *
- * Programmer:  John Mainzer, 6/29/05
- *
- *-------------------------------------------------------------------------
- */
-#ifdef H5_HAVE_PARALLEL
-static herr_t
-H5AC__log_flushed_entry(H5C_t *cache_ptr, haddr_t addr, hbool_t was_dirty,
-    unsigned flags)
-{
-    hbool_t		 cleared;
-    H5AC_aux_t         * aux_ptr;
-    H5AC_slist_entry_t * slist_entry_ptr = NULL;
-    herr_t               ret_value = SUCCEED;    /* Return value */
-
-    FUNC_ENTER_STATIC
-
-    /* Sanity check */
-    HDassert(cache_ptr != NULL);
-    HDassert(cache_ptr->magic == H5C__H5C_T_MAGIC);
-    aux_ptr = (H5AC_aux_t *)(cache_ptr->aux_ptr);
-    HDassert(aux_ptr != NULL);
-    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
-    HDassert(aux_ptr->mpi_rank == 0);
-    HDassert(aux_ptr->c_slist_ptr != NULL);
-
-    /* Set local flags */
-    cleared = ((flags & H5C__FLUSH_CLEAR_ONLY_FLAG) != 0);
-
-    if(cleared) {
-        /* If the entry has been cleared, must remove it from both the
-         * cleaned list and the dirtied list.
-         */
-        if(NULL != (slist_entry_ptr = (H5AC_slist_entry_t *)H5SL_remove(aux_ptr->c_slist_ptr, (void *)(&addr))))
-            slist_entry_ptr = H5FL_FREE(H5AC_slist_entry_t, slist_entry_ptr);
-        if(NULL != (slist_entry_ptr = (H5AC_slist_entry_t *)H5SL_remove(aux_ptr->d_slist_ptr, (void *)(&addr))))
-            slist_entry_ptr = H5FL_FREE(H5AC_slist_entry_t, slist_entry_ptr);
-    } /* end if */
-    else if(was_dirty) {
-        if(NULL == H5SL_search(aux_ptr->c_slist_ptr, (void *)(&addr))) {
-            /* insert the address of the entry in the clean entry list. */
-            if(NULL == (slist_entry_ptr = H5FL_MALLOC(H5AC_slist_entry_t)))
-                HGOTO_ERROR(H5E_CACHE, H5E_CANTALLOC, FAIL, "Can't allocate clean slist entry .")
-            slist_entry_ptr->addr = addr;
-
-            if(H5SL_insert(aux_ptr->c_slist_ptr, slist_entry_ptr, &(slist_entry_ptr->addr)) < 0)
-                HGOTO_ERROR(H5E_CACHE, H5E_CANTINSERT, FAIL, "can't insert entry into clean entry slist.")
-        } /* end if */
-    } /* end else-if */
-
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* H5AC__log_flushed_entry() */
-#endif /* H5_HAVE_PARALLEL */
-
-
-/*-------------------------------------------------------------------------
- *
- * Function:    H5AC__log_inserted_entry()
- *
- * Purpose:     Update the dirty_bytes count for a newly inserted entry.
- *
- *		If mpi_rank isnt 0, this simply means adding the size
- *		of the entry to the dirty_bytes count.
- *
- *		If mpi_rank is 0, we must also add the entry to the
- *		dirty entries slist.
- *
- *		Return SUCCEED on success, and FAIL on failure.
- *
- * Return:      Non-negative on success/Negative on failure.
- *
- * Programmer:  John Mainzer, 6/30/05
- *
- *-------------------------------------------------------------------------
- */
-#ifdef H5_HAVE_PARALLEL
-static herr_t
-H5AC__log_inserted_entry(const H5AC_info_t *entry_ptr)
-{
-    H5AC_t             * cache_ptr;
-    H5AC_aux_t         * aux_ptr;
-    herr_t               ret_value = SUCCEED;    /* Return value */
-
-    FUNC_ENTER_STATIC
-
-    /* Sanity checks */
-    HDassert(entry_ptr);
-    cache_ptr = entry_ptr->cache_ptr;
-    HDassert(cache_ptr != NULL);
-    HDassert(cache_ptr->magic == H5C__H5C_T_MAGIC);
-    aux_ptr = (H5AC_aux_t *)(cache_ptr->aux_ptr);
-    HDassert(aux_ptr != NULL);
-    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
-
-    if(aux_ptr->mpi_rank == 0) {
-        H5AC_slist_entry_t *slist_entry_ptr;
-
-        HDassert(aux_ptr->d_slist_ptr != NULL);
-        HDassert(aux_ptr->c_slist_ptr != NULL);
-
-        /* Entry to insert should not be in dirty list currently */
-        if(NULL != H5SL_search(aux_ptr->d_slist_ptr, (const void *)(&entry_ptr->addr)))
-            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Inserted entry already in dirty slist.")
-
-        /* insert the address of the entry in the dirty entry list, and
-         * add its size to the dirty_bytes count.
-         */
-        if(NULL == (slist_entry_ptr = H5FL_MALLOC(H5AC_slist_entry_t)))
-            HGOTO_ERROR(H5E_CACHE, H5E_CANTALLOC, FAIL, "Can't allocate dirty slist entry .")
-        slist_entry_ptr->addr  = entry_ptr->addr;
-        if(H5SL_insert(aux_ptr->d_slist_ptr, slist_entry_ptr, &(slist_entry_ptr->addr)) < 0)
-            HGOTO_ERROR(H5E_CACHE, H5E_CANTINSERT, FAIL, "can't insert entry into dirty entry slist.")
-
-        /* Entry to insert should not be in clean list either */
-        if(NULL != H5SL_search(aux_ptr->c_slist_ptr, (const void *)(&entry_ptr->addr)))
-            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Inserted entry in clean slist.")
-    } /* end if */
-
-    aux_ptr->dirty_bytes += entry_ptr->size;
-
-#if H5AC_DEBUG_DIRTY_BYTES_CREATION
-    aux_ptr->insert_dirty_bytes += size;
-    aux_ptr->insert_dirty_bytes_updates += 1;
-#endif /* H5AC_DEBUG_DIRTY_BYTES_CREATION */
-
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* H5AC__log_inserted_entry() */
-#endif /* H5_HAVE_PARALLEL */
-
-
-/*-------------------------------------------------------------------------
- *
- * Function:    H5AC__log_moved_entry()
- *
- * Purpose:     Update the dirty_bytes count for a moved entry.
- *
- *		WARNING
- *
- *		At present, the way that the move call is used ensures
- *		that the moved entry is present in all caches by
- *		moving in a collective operation and immediately after
- *		unprotecting the target entry.
- *
- *		This function uses this invariant, and will cause arcane
- *		failures if it is not met.  If maintaining this invariant
- *		becomes impossible, we will have to rework this function
- *		extensively, and likely include a bit of IPC for
- *		synchronization.  A better option might be to subsume
- *		move in the unprotect operation.
- *
- *		Given that the target entry is in all caches, the function
- *		proceeds as follows:
- *
- *		For processes with mpi rank other 0, it simply checks to
- *		see if the entry was dirty prior to the move, and adds
- *		the entries size to the dirty bytes count.
- *
- *		In the process with mpi rank 0, the function first checks
- *		to see if the entry was dirty prior to the move.  If it
- *		was, and if the entry doesn't appear in the dirtied list
- *		under its old address, it adds the entry's size to the
- *		dirty bytes count.
- *
- *		The rank 0 process then removes any references to the
- *		entry under its old address from the cleands and dirtied
- *		lists, and inserts an entry in the dirtied list under the
- *		new address.
- *
- *		Return SUCCEED on success, and FAIL on failure.
- *
- * Return:      Non-negative on success/Negative on failure.
- *
- * Programmer:  John Mainzer, 6/30/05
- *
- *-------------------------------------------------------------------------
- */
-#ifdef H5_HAVE_PARALLEL
-static herr_t
-H5AC__log_moved_entry(const H5F_t *f, haddr_t old_addr, haddr_t new_addr)
-{
-    H5AC_t             * cache_ptr;
-    H5AC_aux_t         * aux_ptr;
-    hbool_t		 entry_in_cache;
-    hbool_t		 entry_dirty;
-    size_t               entry_size;
-    herr_t               ret_value = SUCCEED;    /* Return value */
-
-    FUNC_ENTER_STATIC
-
-    /* Sanity checks */
-    HDassert(f);
-    HDassert(f->shared);
-    cache_ptr = (H5AC_t *)f->shared->cache;
-    HDassert(cache_ptr);
-    HDassert(cache_ptr->magic == H5C__H5C_T_MAGIC);
-    aux_ptr = (H5AC_aux_t *)(cache_ptr->aux_ptr);
-    HDassert(aux_ptr != NULL);
-    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
-
-    /* get entry status, size, etc here */
-    if(H5C_get_entry_status(f, old_addr, &entry_size, &entry_in_cache,
-            &entry_dirty, NULL, NULL, NULL, NULL) < 0)
-        HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't get entry status.")
-    if(!entry_in_cache)
-        HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "entry not in cache.")
-
-    if(aux_ptr->mpi_rank == 0) {
-        H5AC_slist_entry_t * slist_entry_ptr;
-
-        HDassert(aux_ptr->d_slist_ptr != NULL);
-        HDassert(aux_ptr->c_slist_ptr != NULL);
-
-        /* if the entry appears in the cleaned entry slist, under its old
-         * address, remove it.
-         */
-        if(NULL != (slist_entry_ptr = (H5AC_slist_entry_t *)H5SL_remove(aux_ptr->c_slist_ptr, (void *)(&old_addr))))
-            slist_entry_ptr = H5FL_FREE(H5AC_slist_entry_t, slist_entry_ptr);
-
-        /* if the entry appears in the dirtied entry slist under its old
-         * address, remove it, but don't free it. Set addr to new_addr.
-         */
-        if(NULL != (slist_entry_ptr = (H5AC_slist_entry_t *)H5SL_remove(aux_ptr->d_slist_ptr, (void *)(&old_addr))))
-            slist_entry_ptr->addr = new_addr;
-        else {
-             /* otherwise, allocate a new entry that is ready
-              * for insertion, and increment dirty_bytes.
-              *
-              * Note that the fact that the entry wasn't in the dirtied
-              * list under its old address implies that it must have
-              * been clean to start with.
-              */
-            HDassert(!entry_dirty);
-            if(NULL == (slist_entry_ptr = H5FL_MALLOC(H5AC_slist_entry_t)))
-                HGOTO_ERROR(H5E_CACHE, H5E_CANTALLOC, FAIL, "Can't allocate dirty slist entry .")
-            slist_entry_ptr->addr = new_addr;
-
-            aux_ptr->dirty_bytes += entry_size;
-
-#if H5AC_DEBUG_DIRTY_BYTES_CREATION
-            aux_ptr->move_dirty_bytes += entry_size;
-            aux_ptr->move_dirty_bytes_updates += 1;
-#endif /* H5AC_DEBUG_DIRTY_BYTES_CREATION */
-        } /* end else */
-
-        /* insert / reinsert the entry in the dirty slist */
-        if(H5SL_insert(aux_ptr->d_slist_ptr, slist_entry_ptr, &(slist_entry_ptr->addr)) < 0)
-            HGOTO_ERROR(H5E_CACHE, H5E_CANTINSERT, FAIL, "can't insert entry into dirty entry slist.")
-    } /* end if */
-    else if(!entry_dirty) {
-        aux_ptr->dirty_bytes += entry_size;
-
-#if H5AC_DEBUG_DIRTY_BYTES_CREATION
-        aux_ptr->move_dirty_bytes += entry_size;
-        aux_ptr->move_dirty_bytes_updates += 1;
-#endif /* H5AC_DEBUG_DIRTY_BYTES_CREATION */
-    } /* end else-if */
-
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* H5AC__log_moved_entry() */
-#endif /* H5_HAVE_PARALLEL */
-
-
-/*-------------------------------------------------------------------------
- * Function:    H5AC__propagate_and_apply_candidate_list
- *
- * Purpose:     Prior to the addition of support for multiple metadata 
- *		write strategies, in PHDF5, only the metadata cache with 
- *		mpi rank 0 was allowed to write to file.  All other 
- *		metadata caches on processes with rank greater than 0 
- *		were required to retain dirty entries until they were 
- *		notified that the entry was clean.
- *
- *		This constraint is relaxed with the distributed 
- *		metadata write strategy, in which a list of candidate
- *		metadata cache entries is constructed by the process 0
- *		cache and then distributed to the caches of all the other
- *		processes.  Once the listed is distributed, many (if not 
- *		all) processes writing writing a unique subset of the 
- *		entries, and marking the remainder clean.  The subsets 
- *		are chosen so that each entry in the list of candidates 
- *		is written by exactly one cache, and all entries are 
- *		marked as being clean in all caches.
- *
- *		While the list of candidate cache entries is prepared 
- *		elsewhere, this function is the main routine for distributing
- *		and applying the list.  It must be run simultaniously on 
- *		all processes that have the relevant file open.  To ensure
- *		proper synchronization, there is a barrier at the beginning 
- *		of this function.
- *
- *		At present, this function is called under one of two 
- *		circumstances:
- *
- *		1) Dirty byte creation exceeds some user specified value.
- *
- *		   While metadata reads may occur independently, all
- *		   operations writing metadata must be collective.  Thus
- *		   all metadata caches see the same sequence of operations,
- *                 and therefore the same dirty data creation.
- *
- *		   This fact is used to synchronize the caches for purposes
- *                 of propagating the list of candidate entries, by simply 
- *		   calling this function from all caches whenever some user 
- *		   specified threshold on dirty data is exceeded.  (the 
- *		   process 0 cache creates the candidate list just before 
- *		   calling this function).
- *
- *		2) Under direct user control -- this operation must be
- *		   collective.
- *
- *              The operations to be managed by this function are as
- * 		follows:
- *
- *		All processes:
- *
- *		1) Participate in an opening barrier.
- *
- *		For the process with mpi rank 0:
- *
- *		1) Load the contents of the candidate list 
- *		   (candidate_slist_ptr) into a buffer, and broadcast that
- *		   buffer to all the other caches.  Clear the candidate
- *		   list in passing.
- *
- *		If there is a positive number of candidates, proceed with 
- *		the following:
- *
- *		2) Apply the candidate entry list.
- *
- *		3) Particpate in a closing barrier.
- *
- *		4) Remove from the dirty list (d_slist_ptr) and from the 
- *		   flushed and still clean entries list (c_slist_ptr),  
- *                 all addresses that appeared in the candidate list, as
- *		   these entries are now clean.
- *
- *
- *		For all processes with mpi rank greater than 0:
- *
- *		1) Receive the candidate entry list broadcast
- *
- *		If there is a positive number of candidates, proceed with 
- *		the following:
- *
- *		2) Apply the candidate entry list.
- *
- *		3) Particpate in a closing barrier.
- *
- * Return:      Success:        non-negative
- *
- *              Failure:        negative
- *
- * Programmer:  John Mainzer
- *              3/17/10
- *
- *-------------------------------------------------------------------------
- */
-#ifdef H5_HAVE_PARALLEL
-static herr_t
-H5AC__propagate_and_apply_candidate_list(H5F_t  *f, hid_t dxpl_id)
-{
-    H5AC_t             * cache_ptr;
-    H5AC_aux_t         * aux_ptr;
-    haddr_t            * candidates_list_ptr = NULL;
-    int		         mpi_result;
-    int	                 num_candidates = 0;
-    herr_t               ret_value = SUCCEED;   /* Return value */
-
-    FUNC_ENTER_STATIC
-
-    /* Sanity checks */
-    HDassert(f != NULL);
-    cache_ptr = f->shared->cache;
-    HDassert(cache_ptr != NULL);
-    HDassert(cache_ptr->magic == H5C__H5C_T_MAGIC);
-    aux_ptr = (H5AC_aux_t *)(cache_ptr->aux_ptr);
-    HDassert(aux_ptr != NULL);
-    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
-    HDassert(aux_ptr->metadata_write_strategy == H5AC_METADATA_WRITE_STRATEGY__DISTRIBUTED);
-
-    /* to prevent "messages from the future" we must synchronize all
-     * processes before we write any entries.
-     */
-    if(MPI_SUCCESS != (mpi_result = MPI_Barrier(aux_ptr->mpi_comm)))
-        HMPI_GOTO_ERROR(FAIL, "MPI_Barrier failed", mpi_result)
-
-    if(aux_ptr->mpi_rank == 0) {
-        if(H5AC__broadcast_candidate_list(cache_ptr, &num_candidates, &candidates_list_ptr) < 0)
-            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't broadcast candidate slist.")
-
-        HDassert(H5SL_count(aux_ptr->candidate_slist_ptr) == 0);
-    } /* end if */
-    else {
-        if(H5AC__receive_candidate_list(cache_ptr, &num_candidates, &candidates_list_ptr) < 0)
-            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't receive candidate broadcast.")
-    } /* end else */
-
-    if(num_candidates > 0) {
-        herr_t	         result;
-
-        /* all processes apply the candidate list.  
-         * H5C_apply_candidate_list() handles the details of 
-         * distributing the writes across the processes.
-         */
-
-        /* Enable writes during this operation */
-        aux_ptr->write_permitted = TRUE;
-
-        /* Apply the candidate list */
-        result = H5C_apply_candidate_list(f, dxpl_id, dxpl_id, cache_ptr, num_candidates,
-            candidates_list_ptr, aux_ptr->mpi_rank, aux_ptr->mpi_size);
-
-        /* Disable writes again */
-        aux_ptr->write_permitted = FALSE;
-
-        /* Check for error on the write operation */
-        if(result < 0)
-            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't apply candidate list.")
-
-        /* this code exists primarily for the test bed -- it allows us to
-         * enforce posix semantics on the server that pretends to be a 
-         * file system in our parallel tests.
-         */
-	if(aux_ptr->write_done)
-	    (aux_ptr->write_done)();
-
-        /* to prevent "messages from the past" we must synchronize all
-         * processes again before we go on.
-         */
-        if(MPI_SUCCESS != (mpi_result = MPI_Barrier(aux_ptr->mpi_comm)))
-            HMPI_GOTO_ERROR(FAIL, "MPI_Barrier failed", mpi_result)
-
-	/* if this is process zero, tidy up the dirtied,
-         * and flushed and still clean lists.
-         */
-        if(aux_ptr->mpi_rank == 0)
-            if(H5AC__tidy_cache_0_lists(cache_ptr, num_candidates, candidates_list_ptr) < 0)
-                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't tidy up process 0 lists.")
-    } /* end if */
-
-    /* if it is defined, call the sync point done callback.  Note
-     * that this callback is defined purely for testing purposes,
-     * and should be undefined under normal operating circumstances.
-     */
-    if(aux_ptr->sync_point_done)
-        (aux_ptr->sync_point_done)(num_candidates, candidates_list_ptr);
-
-done:
-    if(candidates_list_ptr)
-        candidates_list_ptr = (haddr_t *)H5MM_xfree((void *)candidates_list_ptr);
-
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* H5AC__propagate_and_apply_candidate_list() */
-#endif /* H5_HAVE_PARALLEL */
-
-
-/*-------------------------------------------------------------------------
- * Function:    H5AC__propagate_flushed_and_still_clean_entries_list
- *
- * Purpose:     In PHDF5, if the process 0 only metadata write strategy
- *		is selected, only the metadata cache with mpi rank 0 is 
- *		allowed to write to file.  All other metadata caches on 
- *		processes with rank greater than 0 must retain dirty 
- *		entries until they are notified that the entry is now 
- *		clean.
- *
- *		This function is the main routine for handling this 
- *		notification proceedure.  It must be called 
- *		simultaniously on all processes that have the relevant 
- *		file open.  To this end, it is called only during a 
- *		sync point, with a barrier prior to the call.
- *
- *		Note that any metadata entry writes by process 0 will
- *		occur after the barrier and just before this call.
- *
- *		Typicaly, calls to this function will be triggered in
- *		one of two ways:
- *
- *		1) Dirty byte creation exceeds some user specified value.
- *
- *		   While metadata reads may occur independently, all
- *		   operations writing metadata must be collective.  Thus
- *		   all metadata caches see the same sequence of operations,
- *                 and therefore the same dirty data creation.
- *
- *		   This fact is used to synchronize the caches for purposes
- *                 of propagating the list of flushed and still clean
- *		   entries, by simply calling this function from all
- *		   caches whenever some user specified threshold on dirty
- *		   data is exceeded.
- *
- *		2) Under direct user control -- this operation must be
- *		   collective.
- *
- *              The operations to be managed by this function are as
- * 		follows:
- *
- *		For the process with mpi rank 0:
- *
- *		1) Load the contents of the flushed and still clean entries
- *		   list (c_slist_ptr) into a buffer, and broadcast that
- *		   buffer to all the other caches.
- *
- *		2) Clear the flushed and still clean entries list
- *                 (c_slist_ptr).
- *
- *
- *		For all processes with mpi rank greater than 0:
- *
- *		1) Receive the flushed and still clean entries list broadcast
- *
- *		2) Mark the specified entries as clean.
- *
- *
- *		For all processes:
- *
- *		1) Reset the dirtied bytes count to 0.
- *
- * Return:      Success:        non-negative
- *
- *              Failure:        negative
- *
- * Programmer:  John Mainzer
- *              July 5, 2005
- *
- *-------------------------------------------------------------------------
- */
-#ifdef H5_HAVE_PARALLEL
-static herr_t
-H5AC__propagate_flushed_and_still_clean_entries_list(H5F_t  *f, hid_t dxpl_id)
-{
-    H5AC_t     * cache_ptr;
-    H5AC_aux_t * aux_ptr;
-    herr_t	 ret_value = SUCCEED;   /* Return value */
-
-    FUNC_ENTER_STATIC
-
-    /* Sanity checks */
-    HDassert(f != NULL);
-    cache_ptr = f->shared->cache;
-    HDassert(cache_ptr != NULL);
-    HDassert(cache_ptr->magic == H5C__H5C_T_MAGIC);
-    aux_ptr = (H5AC_aux_t *)(cache_ptr->aux_ptr);
-    HDassert(aux_ptr != NULL);
-    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
-    HDassert(aux_ptr->metadata_write_strategy == H5AC_METADATA_WRITE_STRATEGY__PROCESS_0_ONLY);
-
-    if(aux_ptr->mpi_rank == 0) {
-        if(H5AC__broadcast_clean_list(cache_ptr) < 0)
-            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't broadcast clean slist.")
-        HDassert(H5SL_count(aux_ptr->c_slist_ptr) == 0);
-    } /* end if */
-    else {
-        if(H5AC__receive_and_apply_clean_list(f, dxpl_id, H5AC_dxpl_id) < 0)
-            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't receive and/or process clean slist broadcast.")
-    } /* end else */
-
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* H5AC__propagate_flushed_and_still_clean_entries_list() */
-#endif /* H5_HAVE_PARALLEL */
-
-
-/*-------------------------------------------------------------------------
- *
- * Function:    H5AC_receive_haddr_list()
- *
- * Purpose:     Receive the list of entry addresses from process 0,
- *		and return it in a buffer pointed to by *haddr_buf_ptr_ptr.
- *		Note that the caller must free this buffer if it is 
- *		returned.
- *
- *		This function must only be called by the process with
- *		MPI_rank greater than 0.
- *
- *		Return SUCCEED on success, and FAIL on failure.
- *
- * Return:      Non-negative on success/Negative on failure.
- *
- * Programmer:  Quincey Koziol, 6/11/2015
- *
- *-------------------------------------------------------------------------
- */
-#ifdef H5_HAVE_PARALLEL
-static herr_t
-H5AC__receive_haddr_list(MPI_Comm mpi_comm, int *num_entries_ptr,
-    haddr_t **haddr_buf_ptr_ptr)
-{
-    haddr_t	       * haddr_buf_ptr = NULL;
-    int                  mpi_result;
-    int			 num_entries;
-    herr_t               ret_value = SUCCEED;    /* Return value */
-
-    FUNC_ENTER_STATIC
-
-    /* Sanity checks */
-    HDassert(num_entries_ptr != NULL);
-    HDassert(*num_entries_ptr == 0);
-    HDassert(haddr_buf_ptr_ptr != NULL);
-    HDassert(*haddr_buf_ptr_ptr == NULL);
-
-    /* First receive the number of entries in the list so that we
-     * can set up a buffer to receive them.  If there aren't
-     * any, we are done.
-     */
-    if(MPI_SUCCESS != (mpi_result = MPI_Bcast(&num_entries, 1, MPI_INT, 0, mpi_comm)))
-        HMPI_GOTO_ERROR(FAIL, "MPI_Bcast failed", mpi_result)
-
-    if(num_entries > 0) {
-        size_t buf_size;
-
-        /* allocate buffers to store the list of entry base addresses in */
-        buf_size = sizeof(haddr_t) * (size_t)num_entries;
-        if(NULL == (haddr_buf_ptr = (haddr_t *)H5MM_malloc(buf_size)))
-            HGOTO_ERROR(H5E_CACHE, H5E_CANTALLOC, FAIL, "memory allocation failed for haddr buffer")
-
-        /* Now receive the list of candidate entries */
-        if(MPI_SUCCESS != (mpi_result = MPI_Bcast((void *)haddr_buf_ptr, (int)buf_size, MPI_BYTE, 0, mpi_comm)))
-            HMPI_GOTO_ERROR(FAIL, "MPI_Bcast failed", mpi_result)
-    } /* end if */
-
-    /* finally, pass the number of entries and the buffer pointer 
-     * back to the caller.
-     */
-    *num_entries_ptr = num_entries;
-    *haddr_buf_ptr_ptr = haddr_buf_ptr;
-
-done:
-    if(ret_value < 0)
-        if(haddr_buf_ptr)
-            haddr_buf_ptr = (haddr_t *)H5MM_xfree((void *)haddr_buf_ptr);
-
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* H5AC_receive_haddr_list() */
-#endif /* H5_HAVE_PARALLEL */
-
-
-/*-------------------------------------------------------------------------
- *
- * Function:    H5AC__receive_and_apply_clean_list()
- *
- * Purpose:     Receive the list of cleaned entries from process 0,
- *		and mark the specified entries as clean.
- *
- *		This function must only be called by the process with
- *		MPI_rank greater than 0.
- *
- *		Return SUCCEED on success, and FAIL on failure.
- *
- * Return:      Non-negative on success/Negative on failure.
- *
- * Programmer:  John Mainzer, 7/4/05
- *
- *-------------------------------------------------------------------------
- */
-#ifdef H5_HAVE_PARALLEL
-static herr_t
-H5AC__receive_and_apply_clean_list(H5F_t *f, hid_t primary_dxpl_id, hid_t secondary_dxpl_id)
-{
-    H5AC_t             * cache_ptr;
-    H5AC_aux_t         * aux_ptr;
-    haddr_t	       * haddr_buf_ptr = NULL;
-    int			 num_entries = 0;
-    herr_t               ret_value = SUCCEED;    /* Return value */
-
-    FUNC_ENTER_STATIC
-
-    /* Sanity check */
-    HDassert(f != NULL);
-    cache_ptr = f->shared->cache;
-    HDassert(cache_ptr != NULL);
-    HDassert(cache_ptr->magic == H5C__H5C_T_MAGIC);
-    aux_ptr = (H5AC_aux_t *)(cache_ptr->aux_ptr);
-    HDassert(aux_ptr != NULL);
-    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
-    HDassert(aux_ptr->mpi_rank != 0);
-
-    /* Retrieve the clean list from process 0 */
-    if(H5AC__receive_haddr_list(aux_ptr->mpi_comm, &num_entries, &haddr_buf_ptr) < 0)
-        HGOTO_ERROR(H5E_CACHE, H5E_CANTGET, FAIL, "can't receive clean list")
-
-    if(num_entries > 0)
-        /* mark the indicated entries as clean */
-        if(H5C_mark_entries_as_clean(f, primary_dxpl_id, secondary_dxpl_id, (int32_t)num_entries, haddr_buf_ptr) < 0)
-            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't mark entries clean.")
-
-    /* if it is defined, call the sync point done callback.  Note
-     * that this callback is defined purely for testing purposes,
-     * and should be undefined under normal operating circumstances.
-     */
-    if(aux_ptr->sync_point_done)
-        (aux_ptr->sync_point_done)(num_entries, haddr_buf_ptr);
-
-done:
-    if(haddr_buf_ptr)
-        haddr_buf_ptr = (haddr_t *)H5MM_xfree((void *)haddr_buf_ptr);
-
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* H5AC__receive_and_apply_clean_list() */
-#endif /* H5_HAVE_PARALLEL */
-
-
-/*-------------------------------------------------------------------------
- *
- * Function:    H5AC__receive_candidate_list()
- *
- * Purpose:     Receive the list of candidate entries from process 0,
- *		and return it in a buffer pointed to by *haddr_buf_ptr_ptr.
- *		Note that the caller must free this buffer if it is 
- *		returned.
- *
- *		This function must only be called by the process with
- *		MPI_rank greater than 0.
- *
- *		Return SUCCEED on success, and FAIL on failure.
- *
- * Return:      Non-negative on success/Negative on failure.
- *
- * Programmer:  John Mainzer, 3/17/10
- *
- *-------------------------------------------------------------------------
- */
-#ifdef H5_HAVE_PARALLEL
-static herr_t
-H5AC__receive_candidate_list(const H5AC_t *cache_ptr, int *num_entries_ptr,
-    haddr_t **haddr_buf_ptr_ptr)
-{
-    H5AC_aux_t         * aux_ptr;
-    herr_t               ret_value = SUCCEED;    /* Return value */
-
-    FUNC_ENTER_STATIC
-
-    /* Sanity checks */
-    HDassert(cache_ptr != NULL);
-    HDassert(cache_ptr->magic == H5C__H5C_T_MAGIC);
-    aux_ptr = (H5AC_aux_t *)(cache_ptr->aux_ptr);
-    HDassert(aux_ptr != NULL);
-    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
-    HDassert(aux_ptr->mpi_rank != 0);
-    HDassert(aux_ptr-> metadata_write_strategy == H5AC_METADATA_WRITE_STRATEGY__DISTRIBUTED);
-    HDassert(num_entries_ptr != NULL);
-    HDassert(*num_entries_ptr == 0);
-    HDassert(haddr_buf_ptr_ptr != NULL);
-    HDassert(*haddr_buf_ptr_ptr == NULL);
-
-    /* Retrieve the candidate list from process 0 */
-    if(H5AC__receive_haddr_list(aux_ptr->mpi_comm, num_entries_ptr, haddr_buf_ptr_ptr) < 0)
-        HGOTO_ERROR(H5E_CACHE, H5E_CANTGET, FAIL, "can't receive clean list")
-
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* H5AC__receive_candidate_list() */
-#endif /* H5_HAVE_PARALLEL */
-
-
-/*-------------------------------------------------------------------------
- * Function:    H5AC__rsp__dist_md_write__flush
- *
- * Purpose:     Routine for handling the details of running a sync point
- *		that is triggered by a flush -- which in turn must have been
- *		triggered by either a flush API call or a file close --
- *		when the distributed metadata write strategy is selected.  
- *
- *		Upon entry, each process generates it own candidate list, 
- *              being a sorted list of all dirty metadata entries currently 
- *		in the metadata cache.  Note that this list must be idendical 
- *		across all processes, as all processes see the same stream 
- *		of dirty metadata coming in, and use the same lists of 
- *		candidate entries at each sync point.  (At first glance, this 
- *		argument sounds circular, but think of it in the sense of
- *		a recursive proof).
- *
- *		If this this list is empty, we are done, and the function 
- *		returns
- *
- *		Otherwise, after the sorted list dirty metadata entries is 
- *		constructed, each process uses the same algorithm to assign 
- *		each entry on the candidate list to exactly one process for 
- *		flushing.
- *
- *		At this point, all processes participate in a barrier to
- *		avoid messages from the past/future bugs.
- *
- *		Each process then flushes the entries assigned to it, and 
- *		marks all other entries on the candidate list as clean.
- *
- *		Finally, all processes participate in a second barrier to 
- *		avoid messages from the past/future bugs.
- *
- *		At the end of this process, process 0 and only process 0
- *		must tidy up its lists of dirtied and cleaned entries.   
- *		These lists are not used in the distributed metadata write
- *		strategy, but they must be maintained should we shift 
- *		to a strategy that uses them.
- *
- * Return:      Success:        non-negative
- *
- *              Failure:        negative
- *
- * Programmer:  John Mainzer
- *              April 28, 2010
- *
- *-------------------------------------------------------------------------
- */
-#ifdef H5_HAVE_PARALLEL
-static herr_t
-H5AC__rsp__dist_md_write__flush(H5F_t *f, hid_t dxpl_id)
-{
-    H5AC_t     * cache_ptr;
-    H5AC_aux_t * aux_ptr;
-    haddr_t    * haddr_buf_ptr = NULL;
-    int		 mpi_result;
-    int          num_entries = 0;
-    herr_t	 ret_value = SUCCEED;   /* Return value */
-
-    FUNC_ENTER_STATIC
-
-    /* Sanity checks */
-    HDassert(f != NULL);
-    cache_ptr = f->shared->cache;
-    HDassert(cache_ptr != NULL);
-    HDassert(cache_ptr->magic == H5C__H5C_T_MAGIC);
-    aux_ptr = (H5AC_aux_t *)(cache_ptr->aux_ptr);
-    HDassert(aux_ptr != NULL);
-    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
-    HDassert(aux_ptr->metadata_write_strategy == H5AC_METADATA_WRITE_STRATEGY__DISTRIBUTED);
-
-    /* first construct the candidate list -- initially, this will be in the 
-     * form of a skip list.  We will convert it later.
-     */
-    if(H5C_construct_candidate_list__clean_cache(cache_ptr) < 0)
-        HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "Can't construct candidate list.")
-
-    if(H5SL_count(aux_ptr->candidate_slist_ptr) > 0) {
-        herr_t	 result;
-
-        /* convert the candidate list into the format we
-         * are used to receiving from process 0.
-         */
-        if(H5AC__copy_candidate_list_to_buffer(cache_ptr, &num_entries, &haddr_buf_ptr) < 0)
-            HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "Can't construct candidate buffer.")
-
-        /* initial sync point barrier */
-        if(MPI_SUCCESS != (mpi_result = MPI_Barrier(aux_ptr->mpi_comm)))
-            HMPI_GOTO_ERROR(FAIL, "MPI_Barrier failed", mpi_result)
-
-        /* Enable writes during this operation */
-        aux_ptr->write_permitted = TRUE;
-
-        /* Apply the candidate list */
-        result = H5C_apply_candidate_list(f, dxpl_id, dxpl_id, cache_ptr, num_entries,
-            haddr_buf_ptr, aux_ptr->mpi_rank, aux_ptr->mpi_size);
-
-        /* Disable writes again */
-        aux_ptr->write_permitted = FALSE;
-
-        /* Check for error on the write operation */
-        if(result < 0)
-            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't apply candidate list.")
-
-        /* this code exists primarily for the test bed -- it allows us to
-         * enforce posix semantics on the server that pretends to be a 
-         * file system in our parallel tests.
-         */
-        if(aux_ptr->write_done)
-            (aux_ptr->write_done)();
-
-        /* final sync point barrier */
-        if(MPI_SUCCESS != (mpi_result = MPI_Barrier(aux_ptr->mpi_comm)))
-            HMPI_GOTO_ERROR(FAIL, "MPI_Barrier failed", mpi_result)
-
-	/* if this is process zero, tidy up the dirtied,
-         * and flushed and still clean lists.
-         */
-        if(aux_ptr->mpi_rank == 0)
-            if(H5AC__tidy_cache_0_lists(cache_ptr, num_entries, haddr_buf_ptr) < 0)
-                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't tidy up process 0 lists.")
-    } /* end if */
-
-    /* if it is defined, call the sync point done callback.  Note
-     * that this callback is defined purely for testing purposes,
-     * and should be undefined under normal operating circumstances.
-     */
-    if(aux_ptr->sync_point_done)
-        (aux_ptr->sync_point_done)(num_entries, haddr_buf_ptr);
-
-done:
-    if(haddr_buf_ptr)
-        haddr_buf_ptr = (haddr_t *)H5MM_xfree((void *)haddr_buf_ptr);
-
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* H5AC__rsp__dist_md_write__flush() */
-#endif /* H5_HAVE_PARALLEL */
-
-
-/*-------------------------------------------------------------------------
- * Function:    H5AC__rsp__dist_md_write__flush_to_min_clean
- *
- * Purpose:     Routine for handling the details of running a sync point
- *		triggered by the accumulation of dirty metadata (as 
- *		opposed to a flush call to the API) when the distributed
- *		metadata write strategy is selected.
- *
- *		After invocation and initial sanity checking this function
- *		first checks to see if evictions are enabled -- if they 
- *		are not, the function does nothing and returns.
- *
- *		Otherwise, process zero constructs a list of entries to 
- *		be flushed in order to bring the process zero cache back
- *		within its min clean requirement.  Note that this list 
- *		(the candidate list) may be empty.
- *
- *              Then, all processes participate in a barrier.
- *
- *		After the barrier, process 0 broadcasts the number of 
- *		entries in the candidate list prepared above, and all 
- *		other processes receive this number.
- *
- *		If this number is zero, we are done, and the function
- *		returns without further action.
- *
- *		Otherwise, process 0 broadcasts the sorted list of 
- *		candidate entries, and all other processes receive it.
- *
- *		Then, each process uses the same algorithm to assign 
- *		each entry on the candidate list to exactly one process 
- *		for flushing.
- *
- *		Each process then flushes the entries assigned to it, and 
- *		marks all other entries on the candidate list as clean.
- *
- *		Finally, all processes participate in a second barrier to 
- *		avoid messages from the past/future bugs.
- *
- *		At the end of this process, process 0 and only process 0
- *		must tidy up its lists of dirtied and cleaned entries.   
- *		These lists are not used in the distributed metadata write
- *		strategy, but they must be maintained should we shift 
- *		to a strategy that uses them.
- *
- * Return:      Success:        non-negative
- *
- *              Failure:        negative
- *
- * Programmer:  John Mainzer
- *              April 28, 2010
- *
- *-------------------------------------------------------------------------
- */
-#ifdef H5_HAVE_PARALLEL
-static herr_t
-H5AC__rsp__dist_md_write__flush_to_min_clean(H5F_t *f, hid_t dxpl_id)
-{
-    H5AC_t     * cache_ptr;
-    H5AC_aux_t * aux_ptr;
-    hbool_t 	 evictions_enabled;
-    herr_t	 ret_value = SUCCEED;   /* Return value */
-
-    FUNC_ENTER_STATIC
-
-    /* Sanity checks */
-    HDassert(f != NULL);
-    cache_ptr = f->shared->cache;
-    HDassert(cache_ptr != NULL);
-    HDassert(cache_ptr->magic == H5C__H5C_T_MAGIC);
-    aux_ptr = (H5AC_aux_t *)(cache_ptr->aux_ptr);
-    HDassert(aux_ptr != NULL);
-    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
-    HDassert(aux_ptr->metadata_write_strategy == H5AC_METADATA_WRITE_STRATEGY__DISTRIBUTED);
-
-    /* Query if evictions are allowed */
-    if(H5C_get_evictions_enabled((const H5C_t *)cache_ptr, &evictions_enabled) < 0)
-        HGOTO_ERROR(H5E_CACHE, H5E_CANTGET, FAIL, "H5C_get_evictions_enabled() failed.")
-
-    if(evictions_enabled) {
-        /* construct candidate list -- process 0 only */
-        if(aux_ptr->mpi_rank == 0)
-            if(H5AC__construct_candidate_list(cache_ptr, aux_ptr, H5AC_SYNC_POINT_OP__FLUSH_TO_MIN_CLEAN) < 0)
-                HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "Can't construct candidate list.")
-
-        /* propagate and apply candidate list -- all processes */
-        if(H5AC__propagate_and_apply_candidate_list(f, dxpl_id) < 0)
-            HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "Can't propagate and apply candidate list.")
-    } /* evictions enabled */
-
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* H5AC__rsp__dist_md_write__flush_to_min_clean() */
-#endif /* H5_HAVE_PARALLEL */
-
-
-/*-------------------------------------------------------------------------
- * Function:    H5AC__rsp__p0_only__flush
- *
- * Purpose:     Routine for handling the details of running a sync point
- *		that is triggered a flush -- which in turn must have been
- *		triggered by either a flush API call or a file close -- 
- *		when the process 0 only metadata write strategy is selected.  
- *
- *              First, all processes participate in a barrier.
- *
- *		Then process zero flushes all dirty entries, and broadcasts
- *		they number of clean entries (if any) to all the other 
- *		caches.
- *
- *		If this number is zero, we are done.
- *
- *		Otherwise, process 0 broadcasts the list of cleaned 
- *		entries, and all other processes which are part of this
- *		file group receive it, and mark the listed entries as
- *		clean in their caches.
- *
- *		Since all processes have the same set of dirty 
- *		entries at the beginning of the sync point, and all
- *		entries that will be written are written before 
- *		process zero broadcasts the number of cleaned entries,
- *		there is no need for a closing barrier.
- *
- * Return:      Success:        non-negative
- *
- *              Failure:        negative
- *
- * Programmer:  John Mainzer
- *              April 28, 2010
- *
- *-------------------------------------------------------------------------
- */
-#ifdef H5_HAVE_PARALLEL
-static herr_t
-H5AC__rsp__p0_only__flush(H5F_t *f, hid_t dxpl_id)
-{
-    H5AC_t     * cache_ptr;
-    H5AC_aux_t * aux_ptr;
-    int		 mpi_result;
-    herr_t	 ret_value = SUCCEED;   /* Return value */
-
-    FUNC_ENTER_STATIC
-
-    /* Sanity checks */
-    HDassert(f != NULL);
-    cache_ptr = f->shared->cache;
-    HDassert(cache_ptr != NULL);
-    HDassert(cache_ptr->magic == H5C__H5C_T_MAGIC);
-    aux_ptr = (H5AC_aux_t *)(cache_ptr->aux_ptr);
-    HDassert(aux_ptr != NULL);
-    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
-    HDassert(aux_ptr->metadata_write_strategy == H5AC_METADATA_WRITE_STRATEGY__PROCESS_0_ONLY);
-
-    /* to prevent "messages from the future" we must 
-     * synchronize all processes before we start the flush.  
-     * Hence the following barrier.
-     */
-    if(MPI_SUCCESS != (mpi_result = MPI_Barrier(aux_ptr->mpi_comm)))
-        HMPI_GOTO_ERROR(FAIL, "MPI_Barrier failed", mpi_result)
-
-    /* Flush data to disk, from rank 0 process */
-    if(aux_ptr->mpi_rank == 0) {
-        herr_t        result;
-
-        /* Enable writes during this operation */
-        aux_ptr->write_permitted = TRUE;
-
-        /* Flush the cache */
-        result = H5C_flush_cache(f, dxpl_id, dxpl_id, H5AC__NO_FLAGS_SET);
-
-        /* Disable writes again */
-        aux_ptr->write_permitted = FALSE;
-
-        /* Check for error on the write operation */
-        if(result < 0)
-            HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "Can't flush.")
-
-        /* this code exists primarily for the test bed -- it allows us to
-         * enforce posix semantics on the server that pretends to be a 
-         * file system in our parallel tests.
-         */
-        if(aux_ptr->write_done)
-            (aux_ptr->write_done)();
-    } /* end if */
-
-    /* Propagate cleaned entries to other ranks. */
-    if(H5AC__propagate_flushed_and_still_clean_entries_list(f, H5AC_dxpl_id) < 0)
-        HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "Can't propagate clean entries list.")
-
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* H5AC__rsp__p0_only__flush() */
-#endif /* H5_HAVE_PARALLEL */
-
-
-/*-------------------------------------------------------------------------
- * Function:    H5AC__rsp__p0_only__flush_to_min_clean
- *
- * Purpose:     Routine for handling the details of running a sync point
- *		triggered by the accumulation of dirty metadata (as 
- *		opposed to a flush call to the API) when the process 0
- *		only metadata write strategy is selected.
- *
- *		After invocation and initial sanity checking this function
- *		first checks to see if evictions are enabled -- if they 
- *		are not, the function does nothing and returns.
- *
- *              Otherwise, all processes participate in a barrier.
- *
- *		After the barrier, if this is process 0, the function 
- *		causes the cache to flush sufficient entries to get the 
- *		cache back within its minimum clean fraction, and broadcast 
- *		the number of entries which have been flushed since 
- *		the last sync point, and are still clean.
- *
- *		If this number is zero, we are done.
- *
- *		Otherwise, process 0 broadcasts the list of cleaned 
- *		entries, and all other processes which are part of this
- *		file group receive it, and mark the listed entries as
- *		clean in their caches.
- *
- *		Since all processes have the same set of dirty 
- *		entries at the beginning of the sync point, and all
- *		entries that will be written are written before 
- *		process zero broadcasts the number of cleaned entries,
- *		there is no need for a closing barrier.
- *
- * Return:      Success:        non-negative
- *
- *              Failure:        negative
- *
- * Programmer:  John Mainzer
- *              April 28, 2010
- *
- *-------------------------------------------------------------------------
- */
-#ifdef H5_HAVE_PARALLEL
-static herr_t
-H5AC__rsp__p0_only__flush_to_min_clean(H5F_t *f, hid_t dxpl_id)
-{
-    H5AC_t     * cache_ptr;
-    H5AC_aux_t * aux_ptr;
-    hbool_t 	 evictions_enabled;
-    herr_t	 ret_value = SUCCEED;   /* Return value */
-
-    FUNC_ENTER_STATIC
-
-    /* Sanity checks */
-    HDassert(f != NULL);
-    cache_ptr = f->shared->cache;
-    HDassert(cache_ptr != NULL);
-    HDassert(cache_ptr->magic == H5C__H5C_T_MAGIC);
-    aux_ptr = (H5AC_aux_t *)(cache_ptr->aux_ptr);
-    HDassert(aux_ptr != NULL);
-    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
-    HDassert(aux_ptr->metadata_write_strategy == H5AC_METADATA_WRITE_STRATEGY__PROCESS_0_ONLY);
-
-    /* Query if evictions are allowed */
-    if(H5C_get_evictions_enabled((const H5C_t *)cache_ptr, &evictions_enabled) < 0)
-        HGOTO_ERROR(H5E_CACHE, H5E_CANTGET, FAIL, "H5C_get_evictions_enabled() failed.")
-
-    /* Flush if evictions are allowed -- following call
-     * will cause process 0 to flush to min clean size,
-     * and then propagate the newly clean entries to the
-     * other processes.
-     *
-     * Otherwise, do nothing.
-     */
-    if(evictions_enabled) {
-        int          mpi_result;
-
-        /* to prevent "messages from the future" we must synchronize all
-         * processes before we start the flush.  This synchronization may
-         * already be done -- hence the do_barrier parameter.
-         */
-        if(MPI_SUCCESS != (mpi_result = MPI_Barrier(aux_ptr->mpi_comm)))
-            HMPI_GOTO_ERROR(FAIL, "MPI_Barrier failed", mpi_result)
-
-        if(0 == aux_ptr->mpi_rank) {
-            herr_t	 result;
-
-            /* here, process 0 flushes as many entries as necessary to 
-             * comply with the currently specified min clean size.
-             * Note that it is quite possible that no entries will be 
-             * flushed.
-             */
-
-            /* Enable writes during this operation */
-            aux_ptr->write_permitted = TRUE;
-
-            /* Flush the cache */
-            result = H5C_flush_to_min_clean(f, dxpl_id, H5AC_dxpl_id);
-
-            /* Disable writes again */
-            aux_ptr->write_permitted = FALSE;
-
-            /* Check for error on the write operation */
-            if(result < 0)
-                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "H5C_flush_to_min_clean() failed.")
-
-            /* this call exists primarily for the test code -- it is used
- 	     * to enforce POSIX semantics on the process used to simulate
- 	     * reads and writes in t_cache.c.
-             */
-            if(aux_ptr->write_done)
-                (aux_ptr->write_done)();
-        } /* end if */
-
-        if(H5AC__propagate_flushed_and_still_clean_entries_list(f, dxpl_id) < 0)
-            HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "Can't propagate clean entries list.")
-    } /* end if */
-
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* H5AC__rsp__p0_only__flush_to_min_clean() */
-#endif /* H5_HAVE_PARALLEL */
-
-
-/*-------------------------------------------------------------------------
- * Function:    H5AC__run_sync_point
- *
- * Purpose:     Top level routine for managing a sync point between all
- *		meta data caches in the parallel case.  Since all caches 
- *		see the same sequence of dirty metadata, we simply count
- *		bytes of dirty metadata, and run a sync point whenever the
- *		number of dirty bytes of metadata seen since the last
- *		sync point exceeds a threshold that is common across all
- *		processes.  We also run sync points in response to 
- *		HDF5 API calls triggering either a flush or a file close.
- *
- *		In earlier versions of PHDF5, only the metadata cache with 
- *		mpi rank 0 was allowed to write to file.  All other 
- *		metadata caches on processes with rank greater than 0 were
- *		required to retain dirty entries until they were notified 
- *		that the entry is was clean.
- *
- *		This function was created to make it easier for us to 
- *		experiment with other options, as it is a single point 
- *		for the execution of sync points.  
- *
- * Return:      Success:        non-negative
- *
- *              Failure:        negative
- *
- * Programmer:  John Mainzer
- *              March 11, 2010
- *
- *-------------------------------------------------------------------------
- */
-#ifdef H5_HAVE_PARALLEL
-static herr_t
-H5AC__run_sync_point(H5F_t *f, hid_t dxpl_id, int sync_point_op)
-{
-    H5AC_t     * cache_ptr;
-    H5AC_aux_t * aux_ptr;
-    herr_t	 ret_value = SUCCEED;   /* Return value */
-
-    FUNC_ENTER_STATIC
-
-    /* Sanity checks */
-    HDassert(f != NULL);
-    cache_ptr = f->shared->cache;
-    HDassert(cache_ptr != NULL);
-    HDassert(cache_ptr->magic == H5C__H5C_T_MAGIC);
-    aux_ptr = (H5AC_aux_t *)(cache_ptr->aux_ptr);
-    HDassert(aux_ptr != NULL);
-    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
-    HDassert((sync_point_op == H5AC_SYNC_POINT_OP__FLUSH_TO_MIN_CLEAN) ||
-        (sync_point_op == H5AC_METADATA_WRITE_STRATEGY__DISTRIBUTED));
-
-#if H5AC_DEBUG_DIRTY_BYTES_CREATION
-HDfprintf(stdout, "%d:H5AC_propagate...:%u: (u/uu/i/iu/r/ru) = %zu/%u/%zu/%u/%zu/%u\n",
-    aux_ptr->mpi_rank,
-    aux_ptr->dirty_bytes_propagations,
-    aux_ptr->unprotect_dirty_bytes,
-    aux_ptr->unprotect_dirty_bytes_updates,
-    aux_ptr->insert_dirty_bytes,
-    aux_ptr->insert_dirty_bytes_updates,
-    aux_ptr->rename_dirty_bytes,
-    aux_ptr->rename_dirty_bytes_updates);
-#endif /* H5AC_DEBUG_DIRTY_BYTES_CREATION */
-
-    switch(aux_ptr->metadata_write_strategy) {
-        case H5AC_METADATA_WRITE_STRATEGY__PROCESS_0_ONLY:
-	    switch(sync_point_op) {
-                case H5AC_SYNC_POINT_OP__FLUSH_TO_MIN_CLEAN:
-	            if(H5AC__rsp__p0_only__flush_to_min_clean(f, dxpl_id) < 0)
-                        HGOTO_ERROR(H5E_CACHE, H5E_CANTGET, FAIL, "H5AC__rsp__p0_only__flush_to_min_clean() failed.")
-		    break;
-
-		case H5AC_SYNC_POINT_OP__FLUSH_CACHE:
-	            if(H5AC__rsp__p0_only__flush(f, dxpl_id) < 0)
-                        HGOTO_ERROR(H5E_CACHE, H5E_CANTGET, FAIL, "H5AC__rsp__p0_only__flush() failed.")
-		    break;
-
-		default:
-                    HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "unknown flush op");
-		    break;
-	    } /* end switch */
-	    break;
-
-	case H5AC_METADATA_WRITE_STRATEGY__DISTRIBUTED:
-	    switch(sync_point_op) {
-                case H5AC_SYNC_POINT_OP__FLUSH_TO_MIN_CLEAN:
-	            if(H5AC__rsp__dist_md_write__flush_to_min_clean(f, dxpl_id) < 0)
-                        HGOTO_ERROR(H5E_CACHE, H5E_CANTGET, FAIL, "H5AC__rsp__dist_md_write__flush_to_min_clean() failed.")
-		    break;
-
-		case H5AC_SYNC_POINT_OP__FLUSH_CACHE:
-	            if(H5AC__rsp__dist_md_write__flush(f, dxpl_id) < 0)
-                        HGOTO_ERROR(H5E_CACHE, H5E_CANTGET, FAIL, "H5AC__rsp__dist_md_write__flush() failed.")
-		    break;
-
-		default:
-                    HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "unknown flush op");
-		    break;
-	    } /* end switch */
-	    break;
-
-	default:
-            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Unknown metadata write strategy.")
-	    break;
-    } /* end switch */
-
-    /* reset the dirty bytes count */
-    aux_ptr->dirty_bytes = 0;
-
-#if H5AC_DEBUG_DIRTY_BYTES_CREATION
-    aux_ptr->dirty_bytes_propagations     += 1;
-    aux_ptr->unprotect_dirty_bytes         = 0;
-    aux_ptr->unprotect_dirty_bytes_updates = 0;
-    aux_ptr->insert_dirty_bytes            = 0;
-    aux_ptr->insert_dirty_bytes_updates    = 0;
-    aux_ptr->rename_dirty_bytes            = 0;
-    aux_ptr->rename_dirty_bytes_updates    = 0;
-#endif /* H5AC_DEBUG_DIRTY_BYTES_CREATION */
-
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* H5AC__run_sync_point() */
-#endif /* H5_HAVE_PARALLEL */
-
-
-/*-------------------------------------------------------------------------
- * Function:    H5AC__tidy_cache_0_lists()
- *
- * Purpose:     In the distributed metadata write strategy, not all dirty
- *		entries are written by process 0 -- thus we must tidy
- *		up the dirtied, and flushed and still clean lists 
- *		maintained by process zero after each sync point.
- *
- *		This procedure exists to tend to this issue.
- *
- *		At this point, all entries that process 0 cleared should
- *		have been removed from both the dirty and flushed and 
- *		still clean lists, and entries that process 0 has flushed
- *		should have been removed from the dirtied list and added
- *		to the flushed and still clean list.
- *
- *		However, since the distributed metadata write strategy
- *		doesn't make use of these lists, the objective is simply
- *		to maintain these lists in consistent state that allows
- *		them to be used should the metadata write strategy change
- *		to one that uses these lists.
- *
- *		Thus for our purposes, all we need to do is remove from 
- *		the dirtied and flushed and still clean lists all
- *		references to entries that appear in the candidate list.
- *
- * Return:      Success:        non-negative
- *
- *              Failure:        negative
- *
- * Programmer:  John Mainzer
- *              4/20/10
- *
- *-------------------------------------------------------------------------
- */
-#ifdef H5_HAVE_PARALLEL
-static herr_t
-H5AC__tidy_cache_0_lists(H5AC_t *cache_ptr, int num_candidates,
-    haddr_t *candidates_list_ptr)
-{
-    H5AC_aux_t         * aux_ptr;
-    int                  i;
-
-    FUNC_ENTER_STATIC_NOERR
-
-    /* Sanity checks */
-    HDassert(cache_ptr != NULL);
-    HDassert(cache_ptr->magic == H5C__H5C_T_MAGIC);
-    aux_ptr = (H5AC_aux_t *)(cache_ptr->aux_ptr);
-    HDassert(aux_ptr != NULL);
-    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
-    HDassert(aux_ptr->metadata_write_strategy == H5AC_METADATA_WRITE_STRATEGY__DISTRIBUTED);
-    HDassert(aux_ptr->mpi_rank == 0);
-    HDassert(num_candidates > 0);
-    HDassert(candidates_list_ptr != NULL);
-
-    /* clean up dirtied and flushed and still clean lists by removing 
-     * all entries on the candidate list.  Cleared entries should 
-     * have been removed from both the dirty and cleaned lists at 
-     * this point, flushed entries should have been added to the 
-     * cleaned list.  However, for this metadata write strategy, 
-     * we just want to remove all references to the candidate entries.
-     */
-    for(i = 0; i < num_candidates; i++) {
-        H5AC_slist_entry_t * d_slist_entry_ptr;
-        H5AC_slist_entry_t * c_slist_entry_ptr;
-        haddr_t              addr;
-
-        addr = candidates_list_ptr[i];
-
-        /* addr may be either on the dirtied list, or on the flushed 
-         * and still clean list.  Remove it.
-         */
-        if(NULL != (d_slist_entry_ptr = (H5AC_slist_entry_t *)H5SL_remove(aux_ptr->d_slist_ptr, (void *)&addr)))
-            d_slist_entry_ptr = H5FL_FREE(H5AC_slist_entry_t, d_slist_entry_ptr);
-        if(NULL != (c_slist_entry_ptr = (H5AC_slist_entry_t *)H5SL_remove(aux_ptr->c_slist_ptr, (void *)&addr)))
-            c_slist_entry_ptr = H5FL_FREE(H5AC_slist_entry_t, c_slist_entry_ptr);
-    } /* end for */
-
-    FUNC_LEAVE_NOAPI(SUCCEED)
-} /* H5AC__tidy_cache_0_lists() */
-#endif /* H5_HAVE_PARALLEL */
-
-
-/*-------------------------------------------------------------------------
- * Function:    H5AC__flush_entries
- *
- * Purpose:     Flush the metadata cache associated with the specified file,
- *              only writing from rank 0, but propagating the cleaned entries
- *              to all ranks.
- *
- * Return:      Non-negative on success/Negative on failure if there was a
- *              request to flush all items and something was protected.
- *
- * Programmer:  Quincey Koziol
- *              koziol@hdfgroup.org
- *              Aug 22 2009
- *
- *-------------------------------------------------------------------------
- */
-#ifdef H5_HAVE_PARALLEL
-static herr_t
-H5AC__flush_entries(H5F_t *f, hid_t dxpl_id)
-{
-    herr_t        ret_value = SUCCEED;      /* Return value */
-
-    FUNC_ENTER_STATIC
-
-    /* Sanity checks */
-    HDassert(f);
-    HDassert(f->shared->cache);
-
-    /* Check if we have >1 ranks */
-    if(f->shared->cache->aux_ptr)
-        if(H5AC__run_sync_point(f, dxpl_id, H5AC_SYNC_POINT_OP__FLUSH_CACHE) < 0)
-            HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "Can't run sync point.")
-
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* H5AC__flush_entries() */
-#endif /* H5_HAVE_PARALLEL */
-
-
 /*------------------------------------------------------------------------------
  * Function:    H5AC_ignore_tags()
  *
diff --git a/src/H5ACmpio.c b/src/H5ACmpio.c
new file mode 100644
index 0000000..6c2b924
--- /dev/null
+++ b/src/H5ACmpio.c
@@ -0,0 +1,2274 @@
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * Copyright by The HDF Group.                                               *
+ * Copyright by the Board of Trustees of the University of Illinois.         *
+ * All rights reserved.                                                      *
+ *                                                                           *
+ * This file is part of HDF5.  The full HDF5 copyright notice, including     *
+ * terms governing use, modification, and redistribution, is contained in    *
+ * the files COPYING and Copyright.html.  COPYING can be found at the root   *
+ * of the source code distribution tree; Copyright.html can be found at the  *
+ * root level of an installed copy of the electronic HDF5 document set and   *
+ * is linked from the top-level documents page.  It can also be found at     *
+ * http://hdfgroup.org/HDF5/doc/Copyright.html.  If you do not have          *
+ * access to either file, you may request a copy from help@hdfgroup.org.     *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+/*-------------------------------------------------------------------------
+ *
+ * Created:             H5ACmpio.c
+ *                      Jun 20 2015
+ *                      Quincey Koziol <koziol@hdfgroup.org>
+ *
+ * Purpose:             Functions in this file implement support for parallel
+ *                      I/O cache functionality
+ *
+ *-------------------------------------------------------------------------
+ */
+
+/****************/
+/* Module Setup */
+/****************/
+
+#define H5AC_PACKAGE            /*suppress error about including H5ACpkg  */
+#define H5F_PACKAGE		/*suppress error about including H5Fpkg	  */
+
+/* Interface initialization */
+#define H5_INTERFACE_INIT_FUNC	H5AC__init_mpio_interface
+
+/***********/
+/* Headers */
+/***********/
+#include "H5private.h"		/* Generic Functions			*/
+#include "H5ACpkg.h"		/* Metadata cache			*/
+#include "H5Cprivate.h"		/* Cache                                */
+#include "H5Eprivate.h"		/* Error handling		  	*/
+#include "H5Fpkg.h"		/* Files				*/
+#include "H5MMprivate.h"        /* Memory management                    */
+
+#ifdef H5_HAVE_PARALLEL
+
+/****************/
+/* Local Macros */
+/****************/
+
+
+/******************/
+/* Local Typedefs */
+/******************/
+
+/****************************************************************************
+ *
+ * structure H5AC_slist_entry_t
+ *
+ * The dirty entry list maintained via the d_slist_ptr field of H5AC_aux_t
+ * and the cleaned entry list maintained via the c_slist_ptr field of
+ * H5AC_aux_t are just lists of the file offsets of the dirty/cleaned
+ * entries.  Unfortunately, the slist code makes us define a dynamically
+ * allocated structure to store these offsets in.  This structure serves
+ * that purpose.  Its fields are as follows:
+ *
+ * addr:	file offset of a metadata entry.  Entries are added to this
+ *		list (if they aren't there already) when they are marked
+ *		dirty in an unprotect, inserted, or moved.  They are
+ *		removed when they appear in a clean entries broadcast.
+ *
+ ****************************************************************************/
+typedef struct H5AC_slist_entry_t
+{
+    haddr_t     addr;
+} H5AC_slist_entry_t;
+
+/* User data for address list building callbacks */
+typedef struct H5AC_addr_list_ud_t
+{
+    H5AC_aux_t    * aux_ptr;        /* 'Auxiliary' parallel cache info */
+    haddr_t       * addr_buf_ptr;   /* Array to store addresses */
+    int             i;              /* Counter for position in array */
+} H5AC_addr_list_ud_t;
+
+
+/********************/
+/* Local Prototypes */
+/********************/
+
+static herr_t H5AC__broadcast_candidate_list(H5AC_t *cache_ptr,
+    int *num_entries_ptr, haddr_t **haddr_buf_ptr_ptr);
+static herr_t H5AC__broadcast_clean_list(H5AC_t *cache_ptr);
+static herr_t H5AC__construct_candidate_list(H5AC_t *cache_ptr,
+    H5AC_aux_t *aux_ptr, int sync_point_op);
+static herr_t H5AC__copy_candidate_list_to_buffer(const H5AC_t *cache_ptr,
+    int *num_entries_ptr, haddr_t **haddr_buf_ptr_ptr);
+static herr_t H5AC__propagate_and_apply_candidate_list(H5F_t  *f, hid_t dxpl_id);
+static herr_t H5AC__propagate_flushed_and_still_clean_entries_list(H5F_t  *f,
+    hid_t dxpl_id);
+static herr_t H5AC__receive_haddr_list(MPI_Comm mpi_comm, int *num_entries_ptr,
+    haddr_t **haddr_buf_ptr_ptr);
+static herr_t H5AC__receive_candidate_list(const H5AC_t *cache_ptr,
+    int *num_entries_ptr, haddr_t **haddr_buf_ptr_ptr);
+static herr_t H5AC__receive_and_apply_clean_list(H5F_t *f, hid_t dxpl_id);
+static herr_t H5AC__tidy_cache_0_lists(H5AC_t *cache_ptr, int num_candidates,
+    haddr_t *candidates_list_ptr);
+static herr_t H5AC__rsp__dist_md_write__flush(H5F_t *f, hid_t dxpl_id);
+static herr_t H5AC__rsp__dist_md_write__flush_to_min_clean(H5F_t *f, hid_t dxpl_id);
+static herr_t H5AC__rsp__p0_only__flush(H5F_t *f, hid_t dxpl_id);
+static herr_t H5AC__rsp__p0_only__flush_to_min_clean(H5F_t *f, hid_t dxpl_id);
+
+
+/*********************/
+/* Package Variables */
+/*********************/
+
+/* Declare a free list to manage the H5AC_aux_t struct */
+H5FL_DEFINE(H5AC_aux_t);
+
+
+/*****************************/
+/* Library Private Variables */
+/*****************************/
+
+
+/*******************/
+/* Local Variables */
+/*******************/
+
+/* Declare a free list to manage the H5AC_slist_entry_t struct */
+H5FL_DEFINE_STATIC(H5AC_slist_entry_t);
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5AC__init_mpio_interface
+ *
+ * Purpose:     Initialize interface-specific information
+ *
+ * Return:      Non-negative on success/Negative on failure
+ *
+ * Programmer:  Quincey Koziol
+ *              6/20/15
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5AC__init_mpio_interface(void)
+{
+    herr_t ret_value = SUCCEED;   /* Return value */
+
+    FUNC_ENTER_STATIC
+
+    /* Funnel all work to H5AC_init() */
+    if(H5AC_init() < 0)
+        HGOTO_ERROR(H5E_FUNC, H5E_CANTINIT, FAIL, "interface initialization failed")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5AC__init_mpio_interface() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5AC__set_sync_point_done_callback
+ *
+ * Purpose:     Set the value of the sync_point_done callback.  This 
+ *		callback is used by the parallel test code to verify
+ *		that the expected writes and only the expected writes
+ *		take place during a sync point.
+ *
+ * Return:      Non-negative on success/Negative on failure
+ *
+ * Programmer:  John Mainzer
+ *              5/9/10
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5AC__set_sync_point_done_callback(H5C_t * cache_ptr,
+    void (* sync_point_done)(int num_writes, haddr_t * written_entries_tbl))
+{
+    H5AC_aux_t * aux_ptr;
+
+    FUNC_ENTER_PACKAGE_NOERR
+
+    /* Sanity checks */
+    HDassert(cache_ptr);
+    aux_ptr = H5C_get_aux_ptr(cache_ptr);
+    HDassert(aux_ptr != NULL);
+    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
+
+    aux_ptr->sync_point_done = sync_point_done;
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* H5AC__set_sync_point_done_callback() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5AC__set_write_done_callback
+ *
+ * Purpose:     Set the value of the write_done callback.  This callback
+ *              is used to improve performance of the parallel test bed
+ *              for the cache.
+ *
+ * Return:      Non-negative on success/Negative on failure
+ *
+ * Programmer:  John Mainzer
+ *              5/11/06
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5AC__set_write_done_callback(H5C_t * cache_ptr, void (* write_done)(void))
+{
+    H5AC_aux_t * aux_ptr;
+
+    FUNC_ENTER_PACKAGE_NOERR
+
+    /* Sanity checks */
+    HDassert(cache_ptr);
+    aux_ptr = H5C_get_aux_ptr(cache_ptr);
+    HDassert(aux_ptr != NULL);
+    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
+
+    aux_ptr->write_done = write_done;
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* H5AC__set_write_done_callback() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5AC_add_candidate()
+ *
+ * Purpose:     Add the supplied metadata entry address to the candidate
+ *		list.  Verify that each entry added does not appear in 
+ *		the list prior to its insertion.
+ *
+ *		This function is intended for used in constructing list
+ *		of entried to be flushed during sync points.  It shouldn't
+ *		be called anywhere else.
+ *
+ * Return:      Non-negative on success/Negative on failure
+ *
+ * Programmer:  John Mainzer
+ *              3/17/10
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5AC_add_candidate(H5AC_t * cache_ptr, haddr_t addr)
+{
+    H5AC_aux_t         * aux_ptr;
+    H5AC_slist_entry_t * slist_entry_ptr = NULL;
+    herr_t               ret_value = SUCCEED;    /* Return value */
+
+    FUNC_ENTER_NOAPI(FAIL)
+
+    /* Sanity checks */
+    HDassert(cache_ptr != NULL);
+    aux_ptr = H5C_get_aux_ptr(cache_ptr);
+    HDassert(aux_ptr != NULL);
+    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
+    HDassert(aux_ptr->metadata_write_strategy == H5AC_METADATA_WRITE_STRATEGY__DISTRIBUTED);
+    HDassert(aux_ptr->candidate_slist_ptr != NULL);
+
+    /* Construct an entry for the supplied address, and insert
+     * it into the candidate slist.
+     */
+    if(NULL == (slist_entry_ptr = H5FL_MALLOC(H5AC_slist_entry_t)))
+        HGOTO_ERROR(H5E_CACHE, H5E_CANTALLOC, FAIL, "Can't allocate candidate slist entry")
+    slist_entry_ptr->addr  = addr;
+
+    if(H5SL_insert(aux_ptr->candidate_slist_ptr, slist_entry_ptr, &(slist_entry_ptr->addr)) < 0)
+        HGOTO_ERROR(H5E_CACHE, H5E_CANTINSERT, FAIL, "can't insert entry into dirty entry slist")
+
+done:
+    /* Clean up on error */
+    if(ret_value < 0)
+        if(slist_entry_ptr)
+            slist_entry_ptr = H5FL_FREE(H5AC_slist_entry_t, slist_entry_ptr);
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5AC_add_candidate() */
+
+
+/*-------------------------------------------------------------------------
+ *
+ * Function:    H5AC__broadcast_candidate_list()
+ *
+ * Purpose:     Broadcast the contents of the process 0 candidate entry
+ *		slist.  In passing, also remove all entries from said
+ *		list.  As the application of this will be handled by 
+ *		the same functions on all processes, construct and 
+ *		return a copy of the list in the same format as that
+ *		received by the other processes.  Note that if this
+ *		copy is returned in *haddr_buf_ptr_ptr, the caller 
+ *		must free it.
+ *
+ *		This function must only be called by the process with
+ *		MPI_rank 0.
+ *
+ *		Return SUCCEED on success, and FAIL on failure.
+ *
+ * Return:      Non-negative on success/Negative on failure.
+ *
+ * Programmer:  John Mainzer, 7/1/05
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5AC__broadcast_candidate_list(H5AC_t *cache_ptr, int *num_entries_ptr,
+    haddr_t **haddr_buf_ptr_ptr)
+{
+    H5AC_aux_t         * aux_ptr = NULL;
+    haddr_t            * haddr_buf_ptr = NULL;
+    int                  mpi_result;
+    int			 num_entries;
+    herr_t               ret_value = SUCCEED;    /* Return value */
+
+    FUNC_ENTER_STATIC
+
+    /* Sanity checks */
+    HDassert(cache_ptr != NULL);
+    aux_ptr = H5C_get_aux_ptr(cache_ptr);
+    HDassert(aux_ptr != NULL);
+    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
+    HDassert(aux_ptr->mpi_rank == 0);
+    HDassert(aux_ptr->metadata_write_strategy == H5AC_METADATA_WRITE_STRATEGY__DISTRIBUTED);
+    HDassert(aux_ptr->candidate_slist_ptr != NULL);
+    HDassert(num_entries_ptr != NULL);
+    HDassert(*num_entries_ptr == 0);
+    HDassert(haddr_buf_ptr_ptr != NULL);
+    HDassert(*haddr_buf_ptr_ptr == NULL);
+
+    /* First broadcast the number of entries in the list so that the
+     * receivers can set up buffers to receive them.  If there aren't
+     * any, we are done.
+     */
+    num_entries = (int)H5SL_count(aux_ptr->candidate_slist_ptr);
+    if(MPI_SUCCESS != (mpi_result = MPI_Bcast(&num_entries, 1, MPI_INT, 0, aux_ptr->mpi_comm)))
+        HMPI_GOTO_ERROR(FAIL, "MPI_Bcast failed", mpi_result)
+
+    if(num_entries > 0) {
+        size_t		 buf_size = 0;
+        int		 chk_num_entries = 0;
+
+        /* convert the candidate list into the format we
+         * are used to receiving from process 0, and also load it 
+         * into a buffer for transmission.
+         */
+        if(H5AC__copy_candidate_list_to_buffer(cache_ptr, &chk_num_entries, &haddr_buf_ptr) < 0)
+            HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "Can't construct candidate buffer.")
+        HDassert(chk_num_entries == num_entries);
+        HDassert(haddr_buf_ptr != NULL);
+
+        /* Now broadcast the list of candidate entries */
+        buf_size = sizeof(haddr_t) * (size_t)num_entries;
+        if(MPI_SUCCESS != (mpi_result = MPI_Bcast((void *)haddr_buf_ptr, (int)buf_size, MPI_BYTE, 0, aux_ptr->mpi_comm)))
+            HMPI_GOTO_ERROR(FAIL, "MPI_Bcast failed", mpi_result)
+    } /* end if */
+
+    /* Pass the number of entries and the buffer pointer 
+     * back to the caller.  Do this so that we can use the same code
+     * to apply the candidate list to all the processes.
+     */
+    *num_entries_ptr = num_entries;
+    *haddr_buf_ptr_ptr = haddr_buf_ptr;
+
+done:
+    if(ret_value < 0)
+        if(haddr_buf_ptr)
+            haddr_buf_ptr = (haddr_t *)H5MM_xfree((void *)haddr_buf_ptr);
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5AC__broadcast_candidate_list() */
+
+
+/*-------------------------------------------------------------------------
+ *
+ * Function:    H5AC__broadcast_clean_list_cb()
+ *
+ * Purpose:     Skip list callback for building array of addresses for
+ *              broadcasting the clean list.
+ *
+ * Return:      Non-negative on success/Negative on failure.
+ *
+ * Programmer:  Quincey Koziol, 6/12/15
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5AC__broadcast_clean_list_cb(void *_item, void H5_ATTR_UNUSED *_key,
+    void *_udata)
+{
+    H5AC_slist_entry_t    * slist_entry_ptr = (H5AC_slist_entry_t *)_item;  /* Address of item */
+    H5AC_addr_list_ud_t   * udata = (H5AC_addr_list_ud_t *)_udata;      /* Context for callback */
+    haddr_t		    addr;
+
+    FUNC_ENTER_STATIC_NOERR
+
+    /* Sanity checks */
+    HDassert(slist_entry_ptr);
+    HDassert(udata);
+
+    /* Store the entry's address in the buffer */
+    addr = slist_entry_ptr->addr;
+    udata->addr_buf_ptr[udata->i] = addr;
+    udata->i++;
+
+    /* now release the entry */
+    slist_entry_ptr = H5FL_FREE(H5AC_slist_entry_t, slist_entry_ptr);
+
+    /* and also remove the matching entry from the dirtied list
+     * if it exists.
+     */
+    if(NULL != (slist_entry_ptr = (H5AC_slist_entry_t *)H5SL_remove(udata->aux_ptr->d_slist_ptr, (void *)(&addr))))
+        slist_entry_ptr = H5FL_FREE(H5AC_slist_entry_t, slist_entry_ptr);
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* H5AC__broadcast_clean_list_cb() */
+
+
+/*-------------------------------------------------------------------------
+ *
+ * Function:    H5AC__broadcast_clean_list()
+ *
+ * Purpose:     Broadcast the contents of the process 0 cleaned entry
+ *		slist.  In passing, also remove all entries from said
+ *		list, and also remove any matching entries from the dirtied
+ *		slist.
+ *
+ *		This function must only be called by the process with
+ *		MPI_rank 0.
+ *
+ *		Return SUCCEED on success, and FAIL on failure.
+ *
+ * Return:      Non-negative on success/Negative on failure.
+ *
+ * Programmer:  John Mainzer, 7/1/05
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5AC__broadcast_clean_list(H5AC_t * cache_ptr)
+{
+    haddr_t	       * addr_buf_ptr = NULL;
+    H5AC_aux_t         * aux_ptr;
+    int                  mpi_result;
+    int			 num_entries = 0;
+    herr_t               ret_value = SUCCEED;    /* Return value */
+
+    FUNC_ENTER_STATIC
+
+    /* Sanity checks */
+    HDassert(cache_ptr != NULL);
+    aux_ptr = H5C_get_aux_ptr(cache_ptr);
+    HDassert(aux_ptr != NULL);
+    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
+    HDassert(aux_ptr->mpi_rank == 0);
+    HDassert(aux_ptr->c_slist_ptr != NULL);
+
+    /* First broadcast the number of entries in the list so that the
+     * receives can set up a buffer to receive them.  If there aren't
+     * any, we are done.
+     */
+    num_entries = (int)H5SL_count(aux_ptr->c_slist_ptr);
+    if(MPI_SUCCESS != (mpi_result = MPI_Bcast(&num_entries, 1, MPI_INT, 0, aux_ptr->mpi_comm)))
+        HMPI_GOTO_ERROR(FAIL, "MPI_Bcast failed", mpi_result)
+
+    if(num_entries > 0) {
+        H5AC_addr_list_ud_t udata;
+        size_t		 buf_size;
+
+        /* allocate a buffer to store the list of entry base addresses in */
+        buf_size = sizeof(haddr_t) * (size_t)num_entries;
+        if(NULL == (addr_buf_ptr = (haddr_t *)H5MM_malloc(buf_size)))
+            HGOTO_ERROR(H5E_CACHE, H5E_CANTALLOC, FAIL, "memory allocation failed for addr buffer")
+
+        /* Set up user data for callback */
+        udata.aux_ptr = aux_ptr;
+        udata.addr_buf_ptr = addr_buf_ptr;
+        udata.i = 0;
+
+        /* Free all the clean list entries, building the address list in the callback */
+        /* (Callback also removes the matching entries from the dirtied list) */
+        if(H5SL_free(aux_ptr->c_slist_ptr, H5AC__broadcast_clean_list_cb, &udata) < 0)
+            HGOTO_ERROR(H5E_CACHE, H5E_CANTFREE, FAIL, "Can't build address list for clean entries")
+
+        /* Now broadcast the list of cleaned entries */
+        if(MPI_SUCCESS != (mpi_result = MPI_Bcast((void *)addr_buf_ptr, (int)buf_size, MPI_BYTE, 0, aux_ptr->mpi_comm)))
+            HMPI_GOTO_ERROR(FAIL, "MPI_Bcast failed", mpi_result)
+    } /* end if */
+
+    /* if it is defined, call the sync point done callback.  Note
+     * that this callback is defined purely for testing purposes,
+     * and should be undefined under normal operating circumstances.
+     */
+    if(aux_ptr->sync_point_done)
+        (aux_ptr->sync_point_done)(num_entries, addr_buf_ptr);
+
+done:
+    if(addr_buf_ptr)
+        addr_buf_ptr = (haddr_t *)H5MM_xfree((void *)addr_buf_ptr);
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5AC__broadcast_clean_list() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5AC__construct_candidate_list()
+ *
+ * Purpose:     In the parallel case when the metadata_write_strategy is 
+ *		H5AC_METADATA_WRITE_STRATEGY__DISTRIBUTED, process 0 uses
+ *		this function to construct the list of cache entries to 
+ *		be flushed.  This list is then propagated to the other 
+ *		caches, and then flushed in a distributed fashion.
+ *
+ *		The sync_point_op parameter is used to determine the extent
+ *		of the flush.
+ *
+ * Return:      Non-negative on success/Negative on failure
+ *
+ * Programmer:  John Mainzer
+ *              3/17/10
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5AC__construct_candidate_list(H5AC_t *cache_ptr, H5AC_aux_t *aux_ptr,
+    int sync_point_op)
+{
+    herr_t ret_value = SUCCEED;    /* Return value */
+
+    FUNC_ENTER_STATIC
+
+    /* Sanity checks */
+    HDassert(cache_ptr != NULL);
+    HDassert(aux_ptr != NULL);
+    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
+    HDassert(aux_ptr->metadata_write_strategy == H5AC_METADATA_WRITE_STRATEGY__DISTRIBUTED);
+    HDassert((sync_point_op == H5AC_SYNC_POINT_OP__FLUSH_CACHE) || (aux_ptr->mpi_rank == 0));
+    HDassert(aux_ptr->d_slist_ptr != NULL);
+    HDassert(aux_ptr->c_slist_ptr != NULL);
+    HDassert(H5SL_count(aux_ptr->c_slist_ptr) == 0);
+    HDassert(aux_ptr->candidate_slist_ptr != NULL);
+    HDassert(H5SL_count(aux_ptr->candidate_slist_ptr) == 0);
+    HDassert((sync_point_op == H5AC_SYNC_POINT_OP__FLUSH_TO_MIN_CLEAN) || (sync_point_op == H5AC_SYNC_POINT_OP__FLUSH_CACHE));
+
+    switch(sync_point_op) {
+	case H5AC_SYNC_POINT_OP__FLUSH_TO_MIN_CLEAN:
+            if(H5C_construct_candidate_list__min_clean((H5C_t *)cache_ptr) < 0)
+		HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "H5C_construct_candidate_list__min_clean() failed.")
+	    break;
+
+	case H5AC_SYNC_POINT_OP__FLUSH_CACHE:
+            if(H5C_construct_candidate_list__clean_cache((H5C_t *)cache_ptr) < 0)
+		HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "H5C_construct_candidate_list__clean_cache() failed.")
+	    break;
+
+        default:
+	    HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "unknown sync point operation.")
+	    break;
+    } /* end switch */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5AC__construct_candidate_list() */
+
+
+/*-------------------------------------------------------------------------
+ *
+ * Function:    H5AC__copy_candidate_list_to_buffer_cb
+ *
+ * Purpose:     Skip list callback for building array of addresses for
+ *              broadcasting the candidate list.
+ *
+ * Return:	Return SUCCEED on success, and FAIL on failure.
+ *
+ * Programmer:  Quincey Koziol, 6/12/15
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5AC__copy_candidate_list_to_buffer_cb(void *_item, void H5_ATTR_UNUSED *_key,
+    void *_udata)
+{
+    H5AC_slist_entry_t    * slist_entry_ptr = (H5AC_slist_entry_t *)_item;  /* Address of item */
+    H5AC_addr_list_ud_t   * udata = (H5AC_addr_list_ud_t *)_udata;      /* Context for callback */
+
+    FUNC_ENTER_STATIC_NOERR
+
+    /* Sanity checks */
+    HDassert(slist_entry_ptr);
+    HDassert(udata);
+
+    /* Store the entry's address in the buffer */
+    udata->addr_buf_ptr[udata->i] = slist_entry_ptr->addr;
+    udata->i++;
+
+    /* now release the entry */
+    slist_entry_ptr = H5FL_FREE(H5AC_slist_entry_t, slist_entry_ptr);
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* H5AC__copy_candidate_list_to_buffer_cb() */
+
+
+/*-------------------------------------------------------------------------
+ *
+ * Function:    H5AC__copy_candidate_list_to_buffer
+ *
+ * Purpose:     Allocate buffer(s) and copy the contents of the candidate
+ *		entry slist into it (them).  In passing, remove all 
+ *		entries from the candidate slist.  Note that the 
+ *		candidate slist must not be empty.
+ *
+ *		If MPI_Offset_buf_ptr_ptr is not NULL, allocate a buffer
+ *		of MPI_Offset, copy the contents of the candidate
+ *		entry list into it with the appropriate conversions, 
+ *		and return the base address of the buffer in 
+ *		*MPI_Offset_buf_ptr.  Note that this is the buffer
+ *		used by process 0 to transmit the list of entries to 
+ *		be flushed to all other processes (in this file group).
+ *
+ *		Similarly, allocate a buffer of haddr_t, load the contents
+ *		of the candidate list into this buffer, and return its 
+ *		base address in *haddr_buf_ptr_ptr.  Note that this 
+ *		latter buffer is constructed unconditionally.  
+ *
+ *		In passing, also remove all entries from the candidate
+ *		entry slist.
+ *
+ * Return:	Return SUCCEED on success, and FAIL on failure.
+ *
+ * Programmer:  John Mainzer, 4/19/10
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5AC__copy_candidate_list_to_buffer(const H5AC_t *cache_ptr, int *num_entries_ptr,
+    haddr_t **haddr_buf_ptr_ptr)
+{
+    H5AC_aux_t         * aux_ptr = NULL;
+    H5AC_addr_list_ud_t  udata;
+    haddr_t            * haddr_buf_ptr = NULL;
+    size_t		 buf_size;
+    int			 num_entries = 0;
+    herr_t               ret_value = SUCCEED;    /* Return value */
+
+    FUNC_ENTER_STATIC
+
+    /* Sanity checks */
+    HDassert(cache_ptr != NULL);
+    aux_ptr = H5C_get_aux_ptr(cache_ptr);
+    HDassert(aux_ptr != NULL);
+    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
+    HDassert(aux_ptr->metadata_write_strategy == H5AC_METADATA_WRITE_STRATEGY__DISTRIBUTED);
+    HDassert(aux_ptr->candidate_slist_ptr != NULL);
+    HDassert(H5SL_count(aux_ptr->candidate_slist_ptr) > 0);
+    HDassert(num_entries_ptr != NULL);
+    HDassert(*num_entries_ptr == 0);
+    HDassert(haddr_buf_ptr_ptr != NULL);
+    HDassert(*haddr_buf_ptr_ptr == NULL);
+
+    num_entries = (int)H5SL_count(aux_ptr->candidate_slist_ptr);
+
+    /* allocate a buffer(s) to store the list of candidate entry 
+     * base addresses in 
+     */
+    buf_size = sizeof(haddr_t) * (size_t)num_entries;
+    if(NULL == (haddr_buf_ptr = (haddr_t *)H5MM_malloc(buf_size)))
+        HGOTO_ERROR(H5E_CACHE, H5E_CANTALLOC, FAIL, "memory allocation failed for haddr buffer")
+
+    /* Set up user data for callback */
+    udata.aux_ptr = aux_ptr;
+    udata.addr_buf_ptr = haddr_buf_ptr;
+    udata.i = 0;
+
+    /* Free all the candidate list entries, building the address list in the callback */
+    if(H5SL_free(aux_ptr->candidate_slist_ptr, H5AC__copy_candidate_list_to_buffer_cb, &udata) < 0)
+        HGOTO_ERROR(H5E_CACHE, H5E_CANTFREE, FAIL, "Can't build address list for candidate entries")
+
+    /* Pass the number of entries and the buffer pointer 
+     * back to the caller.
+     */
+    *num_entries_ptr = num_entries;
+    *haddr_buf_ptr_ptr = haddr_buf_ptr;
+
+done:
+    if(ret_value < 0)
+        if(haddr_buf_ptr)
+            haddr_buf_ptr = (haddr_t *)H5MM_xfree((void *)haddr_buf_ptr);
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5AC__copy_candidate_list_to_buffer() */
+
+
+/*-------------------------------------------------------------------------
+ *
+ * Function:    H5AC__log_deleted_entry()
+ *
+ * Purpose:     Log an entry which has been deleted.
+ *
+ *		Only called for mpi_rank 0. We must make sure that the entry
+ *              doesn't appear in the cleaned or dirty entry lists.
+ *
+ *		Return SUCCEED on success, and FAIL on failure.
+ *
+ * Return:      Non-negative on success/Negative on failure.
+ *
+ * Programmer:  John Mainzer, 6/29/05
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5AC__log_deleted_entry(const H5AC_info_t *entry_ptr)
+{
+    H5AC_t             * cache_ptr;
+    H5AC_aux_t         * aux_ptr;
+    H5AC_slist_entry_t * slist_entry_ptr = NULL;
+    haddr_t              addr;
+
+    FUNC_ENTER_PACKAGE_NOERR
+
+    /* Sanity checks */
+    HDassert(entry_ptr);
+    addr = entry_ptr->addr;
+    cache_ptr = entry_ptr->cache_ptr;
+    HDassert(cache_ptr != NULL);
+    aux_ptr = H5C_get_aux_ptr(cache_ptr);
+    HDassert(aux_ptr != NULL);
+    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
+    HDassert(aux_ptr->mpi_rank == 0);
+    HDassert(aux_ptr->d_slist_ptr != NULL);
+    HDassert(aux_ptr->c_slist_ptr != NULL);
+
+    /* if the entry appears in the dirtied entry slist, remove it. */
+    if(NULL != (slist_entry_ptr = (H5AC_slist_entry_t *)H5SL_remove(aux_ptr->d_slist_ptr, (void *)(&addr))))
+        slist_entry_ptr = H5FL_FREE(H5AC_slist_entry_t, slist_entry_ptr);
+
+    /* if the entry appears in the cleaned entry slist, remove it. */
+    if(NULL != (slist_entry_ptr = (H5AC_slist_entry_t *)H5SL_remove(aux_ptr->c_slist_ptr, (void *)(&addr))))
+        slist_entry_ptr = H5FL_FREE(H5AC_slist_entry_t, slist_entry_ptr);
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* H5AC__log_deleted_entry() */
+
+
+/*-------------------------------------------------------------------------
+ *
+ * Function:    H5AC__log_dirtied_entry()
+ *
+ * Purpose:     Update the dirty_bytes count for a newly dirtied entry.
+ *
+ *		If mpi_rank isn't 0, this simply means adding the size
+ *		of the entries to the dirty_bytes count.
+ *
+ *		If mpi_rank is 0, we must first check to see if the entry
+ *		appears in the dirty entries slist.  If it is, do nothing.
+ *		If it isn't, add the size to th dirty_bytes count, add the
+ *		entry to the dirty entries slist, and remove it from the
+ *		cleaned list (if it is present there).
+ *
+ *		Return SUCCEED on success, and FAIL on failure.
+ *
+ * Return:      Non-negative on success/Negative on failure.
+ *
+ * Programmer:  John Mainzer, 6/29/05
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5AC__log_dirtied_entry(const H5AC_info_t *entry_ptr)
+{
+    H5AC_t             * cache_ptr;
+    H5AC_aux_t         * aux_ptr;
+    herr_t               ret_value = SUCCEED;    /* Return value */
+
+    FUNC_ENTER_PACKAGE
+
+    /* Sanity checks */
+    HDassert(entry_ptr);
+    HDassert(entry_ptr->is_dirty == FALSE);
+    cache_ptr = entry_ptr->cache_ptr;
+    HDassert(cache_ptr != NULL);
+    aux_ptr = H5C_get_aux_ptr(cache_ptr);
+    HDassert(aux_ptr != NULL);
+    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
+
+    if(aux_ptr->mpi_rank == 0) {
+        H5AC_slist_entry_t *slist_entry_ptr;
+        haddr_t addr = entry_ptr->addr;
+
+        /* Sanity checks */
+        HDassert(aux_ptr->d_slist_ptr != NULL);
+        HDassert(aux_ptr->c_slist_ptr != NULL);
+
+        if(NULL == H5SL_search(aux_ptr->d_slist_ptr, (void *)(&addr))) {
+            /* insert the address of the entry in the dirty entry list, and
+             * add its size to the dirty_bytes count.
+             */
+            if(NULL == (slist_entry_ptr = H5FL_MALLOC(H5AC_slist_entry_t)))
+                HGOTO_ERROR(H5E_CACHE, H5E_CANTALLOC, FAIL, "Can't allocate dirty slist entry .")
+            slist_entry_ptr->addr  = addr;
+
+            if(H5SL_insert(aux_ptr->d_slist_ptr, slist_entry_ptr, &(slist_entry_ptr->addr)) < 0)
+                HGOTO_ERROR(H5E_CACHE, H5E_CANTINSERT, FAIL, "can't insert entry into dirty entry slist.")
+
+            aux_ptr->dirty_bytes += entry_ptr->size;
+#if H5AC_DEBUG_DIRTY_BYTES_CREATION
+	    aux_ptr->unprotect_dirty_bytes += entry_ptr->size;
+	    aux_ptr->unprotect_dirty_bytes_updates += 1;
+#endif /* H5AC_DEBUG_DIRTY_BYTES_CREATION */
+        } /* end if */
+
+        /* the entry is dirty.  If it exists on the cleaned entries list,
+         * remove it.
+         */
+        if(NULL != (slist_entry_ptr = (H5AC_slist_entry_t *)H5SL_remove(aux_ptr->c_slist_ptr, (void *)(&addr))))
+            slist_entry_ptr = H5FL_FREE(H5AC_slist_entry_t, slist_entry_ptr);
+    } /* end if */
+    else {
+        aux_ptr->dirty_bytes += entry_ptr->size;
+#if H5AC_DEBUG_DIRTY_BYTES_CREATION
+        aux_ptr->unprotect_dirty_bytes += entry_size;
+        aux_ptr->unprotect_dirty_bytes_updates += 1;
+#endif /* H5AC_DEBUG_DIRTY_BYTES_CREATION */
+    } /* end else */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5AC__log_dirtied_entry() */
+
+
+/*-------------------------------------------------------------------------
+ *
+ * Function:    H5AC__log_flushed_entry()
+ *
+ * Purpose:     Update the clean entry slist for the flush of an entry --
+ *		specifically, if the entry has been cleared, remove it
+ * 		from both the cleaned and dirtied lists if it is present.
+ *		Otherwise, if the entry was dirty, insert the indicated
+ *		entry address in the clean slist if it isn't there already.
+ *
+ *		This function is only used in PHDF5, and should only
+ *		be called for the process with mpi rank 0.
+ *
+ *		Return SUCCEED on success, and FAIL on failure.
+ *
+ * Return:      Non-negative on success/Negative on failure.
+ *
+ * Programmer:  John Mainzer, 6/29/05
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5AC__log_flushed_entry(H5C_t *cache_ptr, haddr_t addr, hbool_t was_dirty,
+    unsigned flags)
+{
+    hbool_t		 cleared;
+    H5AC_aux_t         * aux_ptr;
+    H5AC_slist_entry_t * slist_entry_ptr = NULL;
+    herr_t               ret_value = SUCCEED;    /* Return value */
+
+    FUNC_ENTER_PACKAGE
+
+    /* Sanity check */
+    HDassert(cache_ptr != NULL);
+    aux_ptr = H5C_get_aux_ptr(cache_ptr);
+    HDassert(aux_ptr != NULL);
+    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
+    HDassert(aux_ptr->mpi_rank == 0);
+    HDassert(aux_ptr->c_slist_ptr != NULL);
+
+    /* Set local flags */
+    cleared = ((flags & H5C__FLUSH_CLEAR_ONLY_FLAG) != 0);
+
+    if(cleared) {
+        /* If the entry has been cleared, must remove it from both the
+         * cleaned list and the dirtied list.
+         */
+        if(NULL != (slist_entry_ptr = (H5AC_slist_entry_t *)H5SL_remove(aux_ptr->c_slist_ptr, (void *)(&addr))))
+            slist_entry_ptr = H5FL_FREE(H5AC_slist_entry_t, slist_entry_ptr);
+        if(NULL != (slist_entry_ptr = (H5AC_slist_entry_t *)H5SL_remove(aux_ptr->d_slist_ptr, (void *)(&addr))))
+            slist_entry_ptr = H5FL_FREE(H5AC_slist_entry_t, slist_entry_ptr);
+    } /* end if */
+    else if(was_dirty) {
+        if(NULL == H5SL_search(aux_ptr->c_slist_ptr, (void *)(&addr))) {
+            /* insert the address of the entry in the clean entry list. */
+            if(NULL == (slist_entry_ptr = H5FL_MALLOC(H5AC_slist_entry_t)))
+                HGOTO_ERROR(H5E_CACHE, H5E_CANTALLOC, FAIL, "Can't allocate clean slist entry .")
+            slist_entry_ptr->addr = addr;
+
+            if(H5SL_insert(aux_ptr->c_slist_ptr, slist_entry_ptr, &(slist_entry_ptr->addr)) < 0)
+                HGOTO_ERROR(H5E_CACHE, H5E_CANTINSERT, FAIL, "can't insert entry into clean entry slist.")
+        } /* end if */
+    } /* end else-if */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5AC__log_flushed_entry() */
+
+
+/*-------------------------------------------------------------------------
+ *
+ * Function:    H5AC__log_inserted_entry()
+ *
+ * Purpose:     Update the dirty_bytes count for a newly inserted entry.
+ *
+ *		If mpi_rank isnt 0, this simply means adding the size
+ *		of the entry to the dirty_bytes count.
+ *
+ *		If mpi_rank is 0, we must also add the entry to the
+ *		dirty entries slist.
+ *
+ *		Return SUCCEED on success, and FAIL on failure.
+ *
+ * Return:      Non-negative on success/Negative on failure.
+ *
+ * Programmer:  John Mainzer, 6/30/05
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5AC__log_inserted_entry(const H5AC_info_t *entry_ptr)
+{
+    H5AC_t             * cache_ptr;
+    H5AC_aux_t         * aux_ptr;
+    herr_t               ret_value = SUCCEED;    /* Return value */
+
+    FUNC_ENTER_PACKAGE
+
+    /* Sanity checks */
+    HDassert(entry_ptr);
+    cache_ptr = entry_ptr->cache_ptr;
+    HDassert(cache_ptr != NULL);
+    aux_ptr = H5C_get_aux_ptr(cache_ptr);
+    HDassert(aux_ptr != NULL);
+    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
+
+    if(aux_ptr->mpi_rank == 0) {
+        H5AC_slist_entry_t *slist_entry_ptr;
+
+        HDassert(aux_ptr->d_slist_ptr != NULL);
+        HDassert(aux_ptr->c_slist_ptr != NULL);
+
+        /* Entry to insert should not be in dirty list currently */
+        if(NULL != H5SL_search(aux_ptr->d_slist_ptr, (const void *)(&entry_ptr->addr)))
+            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Inserted entry already in dirty slist.")
+
+        /* insert the address of the entry in the dirty entry list, and
+         * add its size to the dirty_bytes count.
+         */
+        if(NULL == (slist_entry_ptr = H5FL_MALLOC(H5AC_slist_entry_t)))
+            HGOTO_ERROR(H5E_CACHE, H5E_CANTALLOC, FAIL, "Can't allocate dirty slist entry .")
+        slist_entry_ptr->addr  = entry_ptr->addr;
+        if(H5SL_insert(aux_ptr->d_slist_ptr, slist_entry_ptr, &(slist_entry_ptr->addr)) < 0)
+            HGOTO_ERROR(H5E_CACHE, H5E_CANTINSERT, FAIL, "can't insert entry into dirty entry slist.")
+
+        /* Entry to insert should not be in clean list either */
+        if(NULL != H5SL_search(aux_ptr->c_slist_ptr, (const void *)(&entry_ptr->addr)))
+            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Inserted entry in clean slist.")
+    } /* end if */
+
+    aux_ptr->dirty_bytes += entry_ptr->size;
+
+#if H5AC_DEBUG_DIRTY_BYTES_CREATION
+    aux_ptr->insert_dirty_bytes += size;
+    aux_ptr->insert_dirty_bytes_updates += 1;
+#endif /* H5AC_DEBUG_DIRTY_BYTES_CREATION */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5AC__log_inserted_entry() */
+
+
+/*-------------------------------------------------------------------------
+ *
+ * Function:    H5AC__log_moved_entry()
+ *
+ * Purpose:     Update the dirty_bytes count for a moved entry.
+ *
+ *		WARNING
+ *
+ *		At present, the way that the move call is used ensures
+ *		that the moved entry is present in all caches by
+ *		moving in a collective operation and immediately after
+ *		unprotecting the target entry.
+ *
+ *		This function uses this invariant, and will cause arcane
+ *		failures if it is not met.  If maintaining this invariant
+ *		becomes impossible, we will have to rework this function
+ *		extensively, and likely include a bit of IPC for
+ *		synchronization.  A better option might be to subsume
+ *		move in the unprotect operation.
+ *
+ *		Given that the target entry is in all caches, the function
+ *		proceeds as follows:
+ *
+ *		For processes with mpi rank other 0, it simply checks to
+ *		see if the entry was dirty prior to the move, and adds
+ *		the entries size to the dirty bytes count.
+ *
+ *		In the process with mpi rank 0, the function first checks
+ *		to see if the entry was dirty prior to the move.  If it
+ *		was, and if the entry doesn't appear in the dirtied list
+ *		under its old address, it adds the entry's size to the
+ *		dirty bytes count.
+ *
+ *		The rank 0 process then removes any references to the
+ *		entry under its old address from the cleands and dirtied
+ *		lists, and inserts an entry in the dirtied list under the
+ *		new address.
+ *
+ *		Return SUCCEED on success, and FAIL on failure.
+ *
+ * Return:      Non-negative on success/Negative on failure.
+ *
+ * Programmer:  John Mainzer, 6/30/05
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5AC__log_moved_entry(const H5F_t *f, haddr_t old_addr, haddr_t new_addr)
+{
+    H5AC_t             * cache_ptr;
+    H5AC_aux_t         * aux_ptr;
+    hbool_t		 entry_in_cache;
+    hbool_t		 entry_dirty;
+    size_t               entry_size;
+    herr_t               ret_value = SUCCEED;    /* Return value */
+
+    FUNC_ENTER_PACKAGE
+
+    /* Sanity checks */
+    HDassert(f);
+    HDassert(f->shared);
+    cache_ptr = (H5AC_t *)f->shared->cache;
+    HDassert(cache_ptr);
+    aux_ptr = H5C_get_aux_ptr(cache_ptr);
+    HDassert(aux_ptr != NULL);
+    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
+
+    /* get entry status, size, etc here */
+    if(H5C_get_entry_status(f, old_addr, &entry_size, &entry_in_cache,
+            &entry_dirty, NULL, NULL, NULL, NULL) < 0)
+        HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't get entry status.")
+    if(!entry_in_cache)
+        HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "entry not in cache.")
+
+    if(aux_ptr->mpi_rank == 0) {
+        H5AC_slist_entry_t * slist_entry_ptr;
+
+        HDassert(aux_ptr->d_slist_ptr != NULL);
+        HDassert(aux_ptr->c_slist_ptr != NULL);
+
+        /* if the entry appears in the cleaned entry slist, under its old
+         * address, remove it.
+         */
+        if(NULL != (slist_entry_ptr = (H5AC_slist_entry_t *)H5SL_remove(aux_ptr->c_slist_ptr, (void *)(&old_addr))))
+            slist_entry_ptr = H5FL_FREE(H5AC_slist_entry_t, slist_entry_ptr);
+
+        /* if the entry appears in the dirtied entry slist under its old
+         * address, remove it, but don't free it. Set addr to new_addr.
+         */
+        if(NULL != (slist_entry_ptr = (H5AC_slist_entry_t *)H5SL_remove(aux_ptr->d_slist_ptr, (void *)(&old_addr))))
+            slist_entry_ptr->addr = new_addr;
+        else {
+             /* otherwise, allocate a new entry that is ready
+              * for insertion, and increment dirty_bytes.
+              *
+              * Note that the fact that the entry wasn't in the dirtied
+              * list under its old address implies that it must have
+              * been clean to start with.
+              */
+            HDassert(!entry_dirty);
+            if(NULL == (slist_entry_ptr = H5FL_MALLOC(H5AC_slist_entry_t)))
+                HGOTO_ERROR(H5E_CACHE, H5E_CANTALLOC, FAIL, "Can't allocate dirty slist entry .")
+            slist_entry_ptr->addr = new_addr;
+
+            aux_ptr->dirty_bytes += entry_size;
+
+#if H5AC_DEBUG_DIRTY_BYTES_CREATION
+            aux_ptr->move_dirty_bytes += entry_size;
+            aux_ptr->move_dirty_bytes_updates += 1;
+#endif /* H5AC_DEBUG_DIRTY_BYTES_CREATION */
+        } /* end else */
+
+        /* insert / reinsert the entry in the dirty slist */
+        if(H5SL_insert(aux_ptr->d_slist_ptr, slist_entry_ptr, &(slist_entry_ptr->addr)) < 0)
+            HGOTO_ERROR(H5E_CACHE, H5E_CANTINSERT, FAIL, "can't insert entry into dirty entry slist.")
+    } /* end if */
+    else if(!entry_dirty) {
+        aux_ptr->dirty_bytes += entry_size;
+
+#if H5AC_DEBUG_DIRTY_BYTES_CREATION
+        aux_ptr->move_dirty_bytes += entry_size;
+        aux_ptr->move_dirty_bytes_updates += 1;
+#endif /* H5AC_DEBUG_DIRTY_BYTES_CREATION */
+    } /* end else-if */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5AC__log_moved_entry() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5AC__propagate_and_apply_candidate_list
+ *
+ * Purpose:     Prior to the addition of support for multiple metadata 
+ *		write strategies, in PHDF5, only the metadata cache with 
+ *		mpi rank 0 was allowed to write to file.  All other 
+ *		metadata caches on processes with rank greater than 0 
+ *		were required to retain dirty entries until they were 
+ *		notified that the entry was clean.
+ *
+ *		This constraint is relaxed with the distributed 
+ *		metadata write strategy, in which a list of candidate
+ *		metadata cache entries is constructed by the process 0
+ *		cache and then distributed to the caches of all the other
+ *		processes.  Once the listed is distributed, many (if not 
+ *		all) processes writing writing a unique subset of the 
+ *		entries, and marking the remainder clean.  The subsets 
+ *		are chosen so that each entry in the list of candidates 
+ *		is written by exactly one cache, and all entries are 
+ *		marked as being clean in all caches.
+ *
+ *		While the list of candidate cache entries is prepared 
+ *		elsewhere, this function is the main routine for distributing
+ *		and applying the list.  It must be run simultaniously on 
+ *		all processes that have the relevant file open.  To ensure
+ *		proper synchronization, there is a barrier at the beginning 
+ *		of this function.
+ *
+ *		At present, this function is called under one of two 
+ *		circumstances:
+ *
+ *		1) Dirty byte creation exceeds some user specified value.
+ *
+ *		   While metadata reads may occur independently, all
+ *		   operations writing metadata must be collective.  Thus
+ *		   all metadata caches see the same sequence of operations,
+ *                 and therefore the same dirty data creation.
+ *
+ *		   This fact is used to synchronize the caches for purposes
+ *                 of propagating the list of candidate entries, by simply 
+ *		   calling this function from all caches whenever some user 
+ *		   specified threshold on dirty data is exceeded.  (the 
+ *		   process 0 cache creates the candidate list just before 
+ *		   calling this function).
+ *
+ *		2) Under direct user control -- this operation must be
+ *		   collective.
+ *
+ *              The operations to be managed by this function are as
+ * 		follows:
+ *
+ *		All processes:
+ *
+ *		1) Participate in an opening barrier.
+ *
+ *		For the process with mpi rank 0:
+ *
+ *		1) Load the contents of the candidate list 
+ *		   (candidate_slist_ptr) into a buffer, and broadcast that
+ *		   buffer to all the other caches.  Clear the candidate
+ *		   list in passing.
+ *
+ *		If there is a positive number of candidates, proceed with 
+ *		the following:
+ *
+ *		2) Apply the candidate entry list.
+ *
+ *		3) Particpate in a closing barrier.
+ *
+ *		4) Remove from the dirty list (d_slist_ptr) and from the 
+ *		   flushed and still clean entries list (c_slist_ptr),  
+ *                 all addresses that appeared in the candidate list, as
+ *		   these entries are now clean.
+ *
+ *
+ *		For all processes with mpi rank greater than 0:
+ *
+ *		1) Receive the candidate entry list broadcast
+ *
+ *		If there is a positive number of candidates, proceed with 
+ *		the following:
+ *
+ *		2) Apply the candidate entry list.
+ *
+ *		3) Particpate in a closing barrier.
+ *
+ * Return:      Success:        non-negative
+ *
+ *              Failure:        negative
+ *
+ * Programmer:  John Mainzer
+ *              3/17/10
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5AC__propagate_and_apply_candidate_list(H5F_t  *f, hid_t dxpl_id)
+{
+    H5AC_t             * cache_ptr;
+    H5AC_aux_t         * aux_ptr;
+    haddr_t            * candidates_list_ptr = NULL;
+    int		         mpi_result;
+    int	                 num_candidates = 0;
+    herr_t               ret_value = SUCCEED;   /* Return value */
+
+    FUNC_ENTER_STATIC
+
+    /* Sanity checks */
+    HDassert(f != NULL);
+    cache_ptr = f->shared->cache;
+    HDassert(cache_ptr != NULL);
+    aux_ptr = H5C_get_aux_ptr(cache_ptr);
+    HDassert(aux_ptr != NULL);
+    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
+    HDassert(aux_ptr->metadata_write_strategy == H5AC_METADATA_WRITE_STRATEGY__DISTRIBUTED);
+
+    /* to prevent "messages from the future" we must synchronize all
+     * processes before we write any entries.
+     */
+    if(MPI_SUCCESS != (mpi_result = MPI_Barrier(aux_ptr->mpi_comm)))
+        HMPI_GOTO_ERROR(FAIL, "MPI_Barrier failed", mpi_result)
+
+    if(aux_ptr->mpi_rank == 0) {
+        if(H5AC__broadcast_candidate_list(cache_ptr, &num_candidates, &candidates_list_ptr) < 0)
+            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't broadcast candidate slist.")
+
+        HDassert(H5SL_count(aux_ptr->candidate_slist_ptr) == 0);
+    } /* end if */
+    else {
+        if(H5AC__receive_candidate_list(cache_ptr, &num_candidates, &candidates_list_ptr) < 0)
+            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't receive candidate broadcast.")
+    } /* end else */
+
+    if(num_candidates > 0) {
+        herr_t	         result;
+
+        /* all processes apply the candidate list.  
+         * H5C_apply_candidate_list() handles the details of 
+         * distributing the writes across the processes.
+         */
+
+        /* Enable writes during this operation */
+        aux_ptr->write_permitted = TRUE;
+
+        /* Apply the candidate list */
+        result = H5C_apply_candidate_list(f, dxpl_id, cache_ptr, num_candidates,
+            candidates_list_ptr, aux_ptr->mpi_rank, aux_ptr->mpi_size);
+
+        /* Disable writes again */
+        aux_ptr->write_permitted = FALSE;
+
+        /* Check for error on the write operation */
+        if(result < 0)
+            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't apply candidate list.")
+
+        /* this code exists primarily for the test bed -- it allows us to
+         * enforce posix semantics on the server that pretends to be a 
+         * file system in our parallel tests.
+         */
+	if(aux_ptr->write_done)
+	    (aux_ptr->write_done)();
+
+        /* to prevent "messages from the past" we must synchronize all
+         * processes again before we go on.
+         */
+        if(MPI_SUCCESS != (mpi_result = MPI_Barrier(aux_ptr->mpi_comm)))
+            HMPI_GOTO_ERROR(FAIL, "MPI_Barrier failed", mpi_result)
+
+	/* if this is process zero, tidy up the dirtied,
+         * and flushed and still clean lists.
+         */
+        if(aux_ptr->mpi_rank == 0)
+            if(H5AC__tidy_cache_0_lists(cache_ptr, num_candidates, candidates_list_ptr) < 0)
+                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't tidy up process 0 lists.")
+    } /* end if */
+
+    /* if it is defined, call the sync point done callback.  Note
+     * that this callback is defined purely for testing purposes,
+     * and should be undefined under normal operating circumstances.
+     */
+    if(aux_ptr->sync_point_done)
+        (aux_ptr->sync_point_done)(num_candidates, candidates_list_ptr);
+
+done:
+    if(candidates_list_ptr)
+        candidates_list_ptr = (haddr_t *)H5MM_xfree((void *)candidates_list_ptr);
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5AC__propagate_and_apply_candidate_list() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5AC__propagate_flushed_and_still_clean_entries_list
+ *
+ * Purpose:     In PHDF5, if the process 0 only metadata write strategy
+ *		is selected, only the metadata cache with mpi rank 0 is 
+ *		allowed to write to file.  All other metadata caches on 
+ *		processes with rank greater than 0 must retain dirty 
+ *		entries until they are notified that the entry is now 
+ *		clean.
+ *
+ *		This function is the main routine for handling this 
+ *		notification proceedure.  It must be called 
+ *		simultaniously on all processes that have the relevant 
+ *		file open.  To this end, it is called only during a 
+ *		sync point, with a barrier prior to the call.
+ *
+ *		Note that any metadata entry writes by process 0 will
+ *		occur after the barrier and just before this call.
+ *
+ *		Typicaly, calls to this function will be triggered in
+ *		one of two ways:
+ *
+ *		1) Dirty byte creation exceeds some user specified value.
+ *
+ *		   While metadata reads may occur independently, all
+ *		   operations writing metadata must be collective.  Thus
+ *		   all metadata caches see the same sequence of operations,
+ *                 and therefore the same dirty data creation.
+ *
+ *		   This fact is used to synchronize the caches for purposes
+ *                 of propagating the list of flushed and still clean
+ *		   entries, by simply calling this function from all
+ *		   caches whenever some user specified threshold on dirty
+ *		   data is exceeded.
+ *
+ *		2) Under direct user control -- this operation must be
+ *		   collective.
+ *
+ *              The operations to be managed by this function are as
+ * 		follows:
+ *
+ *		For the process with mpi rank 0:
+ *
+ *		1) Load the contents of the flushed and still clean entries
+ *		   list (c_slist_ptr) into a buffer, and broadcast that
+ *		   buffer to all the other caches.
+ *
+ *		2) Clear the flushed and still clean entries list
+ *                 (c_slist_ptr).
+ *
+ *
+ *		For all processes with mpi rank greater than 0:
+ *
+ *		1) Receive the flushed and still clean entries list broadcast
+ *
+ *		2) Mark the specified entries as clean.
+ *
+ *
+ *		For all processes:
+ *
+ *		1) Reset the dirtied bytes count to 0.
+ *
+ * Return:      Success:        non-negative
+ *
+ *              Failure:        negative
+ *
+ * Programmer:  John Mainzer
+ *              July 5, 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5AC__propagate_flushed_and_still_clean_entries_list(H5F_t  *f, hid_t dxpl_id)
+{
+    H5AC_t     * cache_ptr;
+    H5AC_aux_t * aux_ptr;
+    herr_t	 ret_value = SUCCEED;   /* Return value */
+
+    FUNC_ENTER_STATIC
+
+    /* Sanity checks */
+    HDassert(f != NULL);
+    cache_ptr = f->shared->cache;
+    HDassert(cache_ptr != NULL);
+    aux_ptr = H5C_get_aux_ptr(cache_ptr);
+    HDassert(aux_ptr != NULL);
+    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
+    HDassert(aux_ptr->metadata_write_strategy == H5AC_METADATA_WRITE_STRATEGY__PROCESS_0_ONLY);
+
+    if(aux_ptr->mpi_rank == 0) {
+        if(H5AC__broadcast_clean_list(cache_ptr) < 0)
+            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't broadcast clean slist.")
+        HDassert(H5SL_count(aux_ptr->c_slist_ptr) == 0);
+    } /* end if */
+    else {
+        if(H5AC__receive_and_apply_clean_list(f, dxpl_id) < 0)
+            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't receive and/or process clean slist broadcast.")
+    } /* end else */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5AC__propagate_flushed_and_still_clean_entries_list() */
+
+
+/*-------------------------------------------------------------------------
+ *
+ * Function:    H5AC_receive_haddr_list()
+ *
+ * Purpose:     Receive the list of entry addresses from process 0,
+ *		and return it in a buffer pointed to by *haddr_buf_ptr_ptr.
+ *		Note that the caller must free this buffer if it is 
+ *		returned.
+ *
+ *		This function must only be called by the process with
+ *		MPI_rank greater than 0.
+ *
+ *		Return SUCCEED on success, and FAIL on failure.
+ *
+ * Return:      Non-negative on success/Negative on failure.
+ *
+ * Programmer:  Quincey Koziol, 6/11/2015
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5AC__receive_haddr_list(MPI_Comm mpi_comm, int *num_entries_ptr,
+    haddr_t **haddr_buf_ptr_ptr)
+{
+    haddr_t	       * haddr_buf_ptr = NULL;
+    int                  mpi_result;
+    int			 num_entries;
+    herr_t               ret_value = SUCCEED;    /* Return value */
+
+    FUNC_ENTER_STATIC
+
+    /* Sanity checks */
+    HDassert(num_entries_ptr != NULL);
+    HDassert(*num_entries_ptr == 0);
+    HDassert(haddr_buf_ptr_ptr != NULL);
+    HDassert(*haddr_buf_ptr_ptr == NULL);
+
+    /* First receive the number of entries in the list so that we
+     * can set up a buffer to receive them.  If there aren't
+     * any, we are done.
+     */
+    if(MPI_SUCCESS != (mpi_result = MPI_Bcast(&num_entries, 1, MPI_INT, 0, mpi_comm)))
+        HMPI_GOTO_ERROR(FAIL, "MPI_Bcast failed", mpi_result)
+
+    if(num_entries > 0) {
+        size_t buf_size;
+
+        /* allocate buffers to store the list of entry base addresses in */
+        buf_size = sizeof(haddr_t) * (size_t)num_entries;
+        if(NULL == (haddr_buf_ptr = (haddr_t *)H5MM_malloc(buf_size)))
+            HGOTO_ERROR(H5E_CACHE, H5E_CANTALLOC, FAIL, "memory allocation failed for haddr buffer")
+
+        /* Now receive the list of candidate entries */
+        if(MPI_SUCCESS != (mpi_result = MPI_Bcast((void *)haddr_buf_ptr, (int)buf_size, MPI_BYTE, 0, mpi_comm)))
+            HMPI_GOTO_ERROR(FAIL, "MPI_Bcast failed", mpi_result)
+    } /* end if */
+
+    /* finally, pass the number of entries and the buffer pointer 
+     * back to the caller.
+     */
+    *num_entries_ptr = num_entries;
+    *haddr_buf_ptr_ptr = haddr_buf_ptr;
+
+done:
+    if(ret_value < 0)
+        if(haddr_buf_ptr)
+            haddr_buf_ptr = (haddr_t *)H5MM_xfree((void *)haddr_buf_ptr);
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5AC_receive_haddr_list() */
+
+
+/*-------------------------------------------------------------------------
+ *
+ * Function:    H5AC__receive_and_apply_clean_list()
+ *
+ * Purpose:     Receive the list of cleaned entries from process 0,
+ *		and mark the specified entries as clean.
+ *
+ *		This function must only be called by the process with
+ *		MPI_rank greater than 0.
+ *
+ *		Return SUCCEED on success, and FAIL on failure.
+ *
+ * Return:      Non-negative on success/Negative on failure.
+ *
+ * Programmer:  John Mainzer, 7/4/05
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5AC__receive_and_apply_clean_list(H5F_t *f, hid_t dxpl_id)
+{
+    H5AC_t             * cache_ptr;
+    H5AC_aux_t         * aux_ptr;
+    haddr_t	       * haddr_buf_ptr = NULL;
+    int			 num_entries = 0;
+    herr_t               ret_value = SUCCEED;    /* Return value */
+
+    FUNC_ENTER_STATIC
+
+    /* Sanity check */
+    HDassert(f != NULL);
+    cache_ptr = f->shared->cache;
+    HDassert(cache_ptr != NULL);
+    aux_ptr = H5C_get_aux_ptr(cache_ptr);
+    HDassert(aux_ptr != NULL);
+    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
+    HDassert(aux_ptr->mpi_rank != 0);
+
+    /* Retrieve the clean list from process 0 */
+    if(H5AC__receive_haddr_list(aux_ptr->mpi_comm, &num_entries, &haddr_buf_ptr) < 0)
+        HGOTO_ERROR(H5E_CACHE, H5E_CANTGET, FAIL, "can't receive clean list")
+
+    if(num_entries > 0)
+        /* mark the indicated entries as clean */
+        if(H5C_mark_entries_as_clean(f, dxpl_id, (int32_t)num_entries, haddr_buf_ptr) < 0)
+            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't mark entries clean.")
+
+    /* if it is defined, call the sync point done callback.  Note
+     * that this callback is defined purely for testing purposes,
+     * and should be undefined under normal operating circumstances.
+     */
+    if(aux_ptr->sync_point_done)
+        (aux_ptr->sync_point_done)(num_entries, haddr_buf_ptr);
+
+done:
+    if(haddr_buf_ptr)
+        haddr_buf_ptr = (haddr_t *)H5MM_xfree((void *)haddr_buf_ptr);
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5AC__receive_and_apply_clean_list() */
+
+
+/*-------------------------------------------------------------------------
+ *
+ * Function:    H5AC__receive_candidate_list()
+ *
+ * Purpose:     Receive the list of candidate entries from process 0,
+ *		and return it in a buffer pointed to by *haddr_buf_ptr_ptr.
+ *		Note that the caller must free this buffer if it is 
+ *		returned.
+ *
+ *		This function must only be called by the process with
+ *		MPI_rank greater than 0.
+ *
+ *		Return SUCCEED on success, and FAIL on failure.
+ *
+ * Return:      Non-negative on success/Negative on failure.
+ *
+ * Programmer:  John Mainzer, 3/17/10
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5AC__receive_candidate_list(const H5AC_t *cache_ptr, int *num_entries_ptr,
+    haddr_t **haddr_buf_ptr_ptr)
+{
+    H5AC_aux_t         * aux_ptr;
+    herr_t               ret_value = SUCCEED;    /* Return value */
+
+    FUNC_ENTER_STATIC
+
+    /* Sanity checks */
+    HDassert(cache_ptr != NULL);
+    aux_ptr = H5C_get_aux_ptr(cache_ptr);
+    HDassert(aux_ptr != NULL);
+    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
+    HDassert(aux_ptr->mpi_rank != 0);
+    HDassert(aux_ptr-> metadata_write_strategy == H5AC_METADATA_WRITE_STRATEGY__DISTRIBUTED);
+    HDassert(num_entries_ptr != NULL);
+    HDassert(*num_entries_ptr == 0);
+    HDassert(haddr_buf_ptr_ptr != NULL);
+    HDassert(*haddr_buf_ptr_ptr == NULL);
+
+    /* Retrieve the candidate list from process 0 */
+    if(H5AC__receive_haddr_list(aux_ptr->mpi_comm, num_entries_ptr, haddr_buf_ptr_ptr) < 0)
+        HGOTO_ERROR(H5E_CACHE, H5E_CANTGET, FAIL, "can't receive clean list")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5AC__receive_candidate_list() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5AC__rsp__dist_md_write__flush
+ *
+ * Purpose:     Routine for handling the details of running a sync point
+ *		that is triggered by a flush -- which in turn must have been
+ *		triggered by either a flush API call or a file close --
+ *		when the distributed metadata write strategy is selected.  
+ *
+ *		Upon entry, each process generates it own candidate list, 
+ *              being a sorted list of all dirty metadata entries currently 
+ *		in the metadata cache.  Note that this list must be idendical 
+ *		across all processes, as all processes see the same stream 
+ *		of dirty metadata coming in, and use the same lists of 
+ *		candidate entries at each sync point.  (At first glance, this 
+ *		argument sounds circular, but think of it in the sense of
+ *		a recursive proof).
+ *
+ *		If this this list is empty, we are done, and the function 
+ *		returns
+ *
+ *		Otherwise, after the sorted list dirty metadata entries is 
+ *		constructed, each process uses the same algorithm to assign 
+ *		each entry on the candidate list to exactly one process for 
+ *		flushing.
+ *
+ *		At this point, all processes participate in a barrier to
+ *		avoid messages from the past/future bugs.
+ *
+ *		Each process then flushes the entries assigned to it, and 
+ *		marks all other entries on the candidate list as clean.
+ *
+ *		Finally, all processes participate in a second barrier to 
+ *		avoid messages from the past/future bugs.
+ *
+ *		At the end of this process, process 0 and only process 0
+ *		must tidy up its lists of dirtied and cleaned entries.   
+ *		These lists are not used in the distributed metadata write
+ *		strategy, but they must be maintained should we shift 
+ *		to a strategy that uses them.
+ *
+ * Return:      Success:        non-negative
+ *
+ *              Failure:        negative
+ *
+ * Programmer:  John Mainzer
+ *              April 28, 2010
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5AC__rsp__dist_md_write__flush(H5F_t *f, hid_t dxpl_id)
+{
+    H5AC_t     * cache_ptr;
+    H5AC_aux_t * aux_ptr;
+    haddr_t    * haddr_buf_ptr = NULL;
+    int		 mpi_result;
+    int          num_entries = 0;
+    herr_t	 ret_value = SUCCEED;   /* Return value */
+
+    FUNC_ENTER_STATIC
+
+    /* Sanity checks */
+    HDassert(f != NULL);
+    cache_ptr = f->shared->cache;
+    HDassert(cache_ptr != NULL);
+    aux_ptr = H5C_get_aux_ptr(cache_ptr);
+    HDassert(aux_ptr != NULL);
+    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
+    HDassert(aux_ptr->metadata_write_strategy == H5AC_METADATA_WRITE_STRATEGY__DISTRIBUTED);
+
+    /* first construct the candidate list -- initially, this will be in the 
+     * form of a skip list.  We will convert it later.
+     */
+    if(H5C_construct_candidate_list__clean_cache(cache_ptr) < 0)
+        HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "Can't construct candidate list.")
+
+    if(H5SL_count(aux_ptr->candidate_slist_ptr) > 0) {
+        herr_t	 result;
+
+        /* convert the candidate list into the format we
+         * are used to receiving from process 0.
+         */
+        if(H5AC__copy_candidate_list_to_buffer(cache_ptr, &num_entries, &haddr_buf_ptr) < 0)
+            HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "Can't construct candidate buffer.")
+
+        /* initial sync point barrier */
+        if(MPI_SUCCESS != (mpi_result = MPI_Barrier(aux_ptr->mpi_comm)))
+            HMPI_GOTO_ERROR(FAIL, "MPI_Barrier failed", mpi_result)
+
+        /* Enable writes during this operation */
+        aux_ptr->write_permitted = TRUE;
+
+        /* Apply the candidate list */
+        result = H5C_apply_candidate_list(f, dxpl_id, cache_ptr, num_entries,
+            haddr_buf_ptr, aux_ptr->mpi_rank, aux_ptr->mpi_size);
+
+        /* Disable writes again */
+        aux_ptr->write_permitted = FALSE;
+
+        /* Check for error on the write operation */
+        if(result < 0)
+            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't apply candidate list.")
+
+        /* this code exists primarily for the test bed -- it allows us to
+         * enforce posix semantics on the server that pretends to be a 
+         * file system in our parallel tests.
+         */
+        if(aux_ptr->write_done)
+            (aux_ptr->write_done)();
+
+        /* final sync point barrier */
+        if(MPI_SUCCESS != (mpi_result = MPI_Barrier(aux_ptr->mpi_comm)))
+            HMPI_GOTO_ERROR(FAIL, "MPI_Barrier failed", mpi_result)
+
+	/* if this is process zero, tidy up the dirtied,
+         * and flushed and still clean lists.
+         */
+        if(aux_ptr->mpi_rank == 0)
+            if(H5AC__tidy_cache_0_lists(cache_ptr, num_entries, haddr_buf_ptr) < 0)
+                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't tidy up process 0 lists.")
+    } /* end if */
+
+    /* if it is defined, call the sync point done callback.  Note
+     * that this callback is defined purely for testing purposes,
+     * and should be undefined under normal operating circumstances.
+     */
+    if(aux_ptr->sync_point_done)
+        (aux_ptr->sync_point_done)(num_entries, haddr_buf_ptr);
+
+done:
+    if(haddr_buf_ptr)
+        haddr_buf_ptr = (haddr_t *)H5MM_xfree((void *)haddr_buf_ptr);
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5AC__rsp__dist_md_write__flush() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5AC__rsp__dist_md_write__flush_to_min_clean
+ *
+ * Purpose:     Routine for handling the details of running a sync point
+ *		triggered by the accumulation of dirty metadata (as 
+ *		opposed to a flush call to the API) when the distributed
+ *		metadata write strategy is selected.
+ *
+ *		After invocation and initial sanity checking this function
+ *		first checks to see if evictions are enabled -- if they 
+ *		are not, the function does nothing and returns.
+ *
+ *		Otherwise, process zero constructs a list of entries to 
+ *		be flushed in order to bring the process zero cache back
+ *		within its min clean requirement.  Note that this list 
+ *		(the candidate list) may be empty.
+ *
+ *              Then, all processes participate in a barrier.
+ *
+ *		After the barrier, process 0 broadcasts the number of 
+ *		entries in the candidate list prepared above, and all 
+ *		other processes receive this number.
+ *
+ *		If this number is zero, we are done, and the function
+ *		returns without further action.
+ *
+ *		Otherwise, process 0 broadcasts the sorted list of 
+ *		candidate entries, and all other processes receive it.
+ *
+ *		Then, each process uses the same algorithm to assign 
+ *		each entry on the candidate list to exactly one process 
+ *		for flushing.
+ *
+ *		Each process then flushes the entries assigned to it, and 
+ *		marks all other entries on the candidate list as clean.
+ *
+ *		Finally, all processes participate in a second barrier to 
+ *		avoid messages from the past/future bugs.
+ *
+ *		At the end of this process, process 0 and only process 0
+ *		must tidy up its lists of dirtied and cleaned entries.   
+ *		These lists are not used in the distributed metadata write
+ *		strategy, but they must be maintained should we shift 
+ *		to a strategy that uses them.
+ *
+ * Return:      Success:        non-negative
+ *
+ *              Failure:        negative
+ *
+ * Programmer:  John Mainzer
+ *              April 28, 2010
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5AC__rsp__dist_md_write__flush_to_min_clean(H5F_t *f, hid_t dxpl_id)
+{
+    H5AC_t     * cache_ptr;
+    H5AC_aux_t * aux_ptr;
+    hbool_t 	 evictions_enabled;
+    herr_t	 ret_value = SUCCEED;   /* Return value */
+
+    FUNC_ENTER_STATIC
+
+    /* Sanity checks */
+    HDassert(f != NULL);
+    cache_ptr = f->shared->cache;
+    HDassert(cache_ptr != NULL);
+    aux_ptr = H5C_get_aux_ptr(cache_ptr);
+    HDassert(aux_ptr != NULL);
+    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
+    HDassert(aux_ptr->metadata_write_strategy == H5AC_METADATA_WRITE_STRATEGY__DISTRIBUTED);
+
+    /* Query if evictions are allowed */
+    if(H5C_get_evictions_enabled((const H5C_t *)cache_ptr, &evictions_enabled) < 0)
+        HGOTO_ERROR(H5E_CACHE, H5E_CANTGET, FAIL, "H5C_get_evictions_enabled() failed.")
+
+    if(evictions_enabled) {
+        /* construct candidate list -- process 0 only */
+        if(aux_ptr->mpi_rank == 0)
+            if(H5AC__construct_candidate_list(cache_ptr, aux_ptr, H5AC_SYNC_POINT_OP__FLUSH_TO_MIN_CLEAN) < 0)
+                HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "Can't construct candidate list.")
+
+        /* propagate and apply candidate list -- all processes */
+        if(H5AC__propagate_and_apply_candidate_list(f, dxpl_id) < 0)
+            HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "Can't propagate and apply candidate list.")
+    } /* evictions enabled */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5AC__rsp__dist_md_write__flush_to_min_clean() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5AC__rsp__p0_only__flush
+ *
+ * Purpose:     Routine for handling the details of running a sync point
+ *		that is triggered a flush -- which in turn must have been
+ *		triggered by either a flush API call or a file close -- 
+ *		when the process 0 only metadata write strategy is selected.  
+ *
+ *              First, all processes participate in a barrier.
+ *
+ *		Then process zero flushes all dirty entries, and broadcasts
+ *		they number of clean entries (if any) to all the other 
+ *		caches.
+ *
+ *		If this number is zero, we are done.
+ *
+ *		Otherwise, process 0 broadcasts the list of cleaned 
+ *		entries, and all other processes which are part of this
+ *		file group receive it, and mark the listed entries as
+ *		clean in their caches.
+ *
+ *		Since all processes have the same set of dirty 
+ *		entries at the beginning of the sync point, and all
+ *		entries that will be written are written before 
+ *		process zero broadcasts the number of cleaned entries,
+ *		there is no need for a closing barrier.
+ *
+ * Return:      Success:        non-negative
+ *
+ *              Failure:        negative
+ *
+ * Programmer:  John Mainzer
+ *              April 28, 2010
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5AC__rsp__p0_only__flush(H5F_t *f, hid_t dxpl_id)
+{
+    H5AC_t     * cache_ptr;
+    H5AC_aux_t * aux_ptr;
+    int		 mpi_result;
+    herr_t	 ret_value = SUCCEED;   /* Return value */
+
+    FUNC_ENTER_STATIC
+
+    /* Sanity checks */
+    HDassert(f != NULL);
+    cache_ptr = f->shared->cache;
+    HDassert(cache_ptr != NULL);
+    aux_ptr = H5C_get_aux_ptr(cache_ptr);
+    HDassert(aux_ptr != NULL);
+    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
+    HDassert(aux_ptr->metadata_write_strategy == H5AC_METADATA_WRITE_STRATEGY__PROCESS_0_ONLY);
+
+    /* to prevent "messages from the future" we must 
+     * synchronize all processes before we start the flush.  
+     * Hence the following barrier.
+     */
+    if(MPI_SUCCESS != (mpi_result = MPI_Barrier(aux_ptr->mpi_comm)))
+        HMPI_GOTO_ERROR(FAIL, "MPI_Barrier failed", mpi_result)
+
+    /* Flush data to disk, from rank 0 process */
+    if(aux_ptr->mpi_rank == 0) {
+        herr_t        result;
+
+        /* Enable writes during this operation */
+        aux_ptr->write_permitted = TRUE;
+
+        /* Flush the cache */
+        result = H5C_flush_cache(f, dxpl_id, H5AC__NO_FLAGS_SET);
+
+        /* Disable writes again */
+        aux_ptr->write_permitted = FALSE;
+
+        /* Check for error on the write operation */
+        if(result < 0)
+            HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "Can't flush.")
+
+        /* this code exists primarily for the test bed -- it allows us to
+         * enforce posix semantics on the server that pretends to be a 
+         * file system in our parallel tests.
+         */
+        if(aux_ptr->write_done)
+            (aux_ptr->write_done)();
+    } /* end if */
+
+    /* Propagate cleaned entries to other ranks. */
+    if(H5AC__propagate_flushed_and_still_clean_entries_list(f, H5AC_dxpl_id) < 0)
+        HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "Can't propagate clean entries list.")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5AC__rsp__p0_only__flush() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5AC__rsp__p0_only__flush_to_min_clean
+ *
+ * Purpose:     Routine for handling the details of running a sync point
+ *		triggered by the accumulation of dirty metadata (as 
+ *		opposed to a flush call to the API) when the process 0
+ *		only metadata write strategy is selected.
+ *
+ *		After invocation and initial sanity checking this function
+ *		first checks to see if evictions are enabled -- if they 
+ *		are not, the function does nothing and returns.
+ *
+ *              Otherwise, all processes participate in a barrier.
+ *
+ *		After the barrier, if this is process 0, the function 
+ *		causes the cache to flush sufficient entries to get the 
+ *		cache back within its minimum clean fraction, and broadcast 
+ *		the number of entries which have been flushed since 
+ *		the last sync point, and are still clean.
+ *
+ *		If this number is zero, we are done.
+ *
+ *		Otherwise, process 0 broadcasts the list of cleaned 
+ *		entries, and all other processes which are part of this
+ *		file group receive it, and mark the listed entries as
+ *		clean in their caches.
+ *
+ *		Since all processes have the same set of dirty 
+ *		entries at the beginning of the sync point, and all
+ *		entries that will be written are written before 
+ *		process zero broadcasts the number of cleaned entries,
+ *		there is no need for a closing barrier.
+ *
+ * Return:      Success:        non-negative
+ *
+ *              Failure:        negative
+ *
+ * Programmer:  John Mainzer
+ *              April 28, 2010
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5AC__rsp__p0_only__flush_to_min_clean(H5F_t *f, hid_t dxpl_id)
+{
+    H5AC_t     * cache_ptr;
+    H5AC_aux_t * aux_ptr;
+    hbool_t 	 evictions_enabled;
+    herr_t	 ret_value = SUCCEED;   /* Return value */
+
+    FUNC_ENTER_STATIC
+
+    /* Sanity checks */
+    HDassert(f != NULL);
+    cache_ptr = f->shared->cache;
+    HDassert(cache_ptr != NULL);
+    aux_ptr = H5C_get_aux_ptr(cache_ptr);
+    HDassert(aux_ptr != NULL);
+    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
+    HDassert(aux_ptr->metadata_write_strategy == H5AC_METADATA_WRITE_STRATEGY__PROCESS_0_ONLY);
+
+    /* Query if evictions are allowed */
+    if(H5C_get_evictions_enabled((const H5C_t *)cache_ptr, &evictions_enabled) < 0)
+        HGOTO_ERROR(H5E_CACHE, H5E_CANTGET, FAIL, "H5C_get_evictions_enabled() failed.")
+
+    /* Flush if evictions are allowed -- following call
+     * will cause process 0 to flush to min clean size,
+     * and then propagate the newly clean entries to the
+     * other processes.
+     *
+     * Otherwise, do nothing.
+     */
+    if(evictions_enabled) {
+        int          mpi_result;
+
+        /* to prevent "messages from the future" we must synchronize all
+         * processes before we start the flush.  This synchronization may
+         * already be done -- hence the do_barrier parameter.
+         */
+        if(MPI_SUCCESS != (mpi_result = MPI_Barrier(aux_ptr->mpi_comm)))
+            HMPI_GOTO_ERROR(FAIL, "MPI_Barrier failed", mpi_result)
+
+        if(0 == aux_ptr->mpi_rank) {
+            herr_t	 result;
+
+            /* here, process 0 flushes as many entries as necessary to 
+             * comply with the currently specified min clean size.
+             * Note that it is quite possible that no entries will be 
+             * flushed.
+             */
+
+            /* Enable writes during this operation */
+            aux_ptr->write_permitted = TRUE;
+
+            /* Flush the cache */
+            result = H5C_flush_to_min_clean(f, dxpl_id);
+
+            /* Disable writes again */
+            aux_ptr->write_permitted = FALSE;
+
+            /* Check for error on the write operation */
+            if(result < 0)
+                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "H5C_flush_to_min_clean() failed.")
+
+            /* this call exists primarily for the test code -- it is used
+ 	     * to enforce POSIX semantics on the process used to simulate
+ 	     * reads and writes in t_cache.c.
+             */
+            if(aux_ptr->write_done)
+                (aux_ptr->write_done)();
+        } /* end if */
+
+        if(H5AC__propagate_flushed_and_still_clean_entries_list(f, dxpl_id) < 0)
+            HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "Can't propagate clean entries list.")
+    } /* end if */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5AC__rsp__p0_only__flush_to_min_clean() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5AC__run_sync_point
+ *
+ * Purpose:     Top level routine for managing a sync point between all
+ *		meta data caches in the parallel case.  Since all caches 
+ *		see the same sequence of dirty metadata, we simply count
+ *		bytes of dirty metadata, and run a sync point whenever the
+ *		number of dirty bytes of metadata seen since the last
+ *		sync point exceeds a threshold that is common across all
+ *		processes.  We also run sync points in response to 
+ *		HDF5 API calls triggering either a flush or a file close.
+ *
+ *		In earlier versions of PHDF5, only the metadata cache with 
+ *		mpi rank 0 was allowed to write to file.  All other 
+ *		metadata caches on processes with rank greater than 0 were
+ *		required to retain dirty entries until they were notified 
+ *		that the entry is was clean.
+ *
+ *		This function was created to make it easier for us to 
+ *		experiment with other options, as it is a single point 
+ *		for the execution of sync points.  
+ *
+ * Return:      Success:        non-negative
+ *
+ *              Failure:        negative
+ *
+ * Programmer:  John Mainzer
+ *              March 11, 2010
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5AC__run_sync_point(H5F_t *f, hid_t dxpl_id, int sync_point_op)
+{
+    H5AC_t     * cache_ptr;
+    H5AC_aux_t * aux_ptr;
+    herr_t	 ret_value = SUCCEED;   /* Return value */
+
+    FUNC_ENTER_PACKAGE
+
+    /* Sanity checks */
+    HDassert(f != NULL);
+    cache_ptr = f->shared->cache;
+    HDassert(cache_ptr != NULL);
+    aux_ptr = H5C_get_aux_ptr(cache_ptr);
+    HDassert(aux_ptr != NULL);
+    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
+    HDassert((sync_point_op == H5AC_SYNC_POINT_OP__FLUSH_TO_MIN_CLEAN) ||
+        (sync_point_op == H5AC_METADATA_WRITE_STRATEGY__DISTRIBUTED));
+
+#if H5AC_DEBUG_DIRTY_BYTES_CREATION
+HDfprintf(stdout, "%d:H5AC_propagate...:%u: (u/uu/i/iu/r/ru) = %zu/%u/%zu/%u/%zu/%u\n",
+    aux_ptr->mpi_rank,
+    aux_ptr->dirty_bytes_propagations,
+    aux_ptr->unprotect_dirty_bytes,
+    aux_ptr->unprotect_dirty_bytes_updates,
+    aux_ptr->insert_dirty_bytes,
+    aux_ptr->insert_dirty_bytes_updates,
+    aux_ptr->rename_dirty_bytes,
+    aux_ptr->rename_dirty_bytes_updates);
+#endif /* H5AC_DEBUG_DIRTY_BYTES_CREATION */
+
+    switch(aux_ptr->metadata_write_strategy) {
+        case H5AC_METADATA_WRITE_STRATEGY__PROCESS_0_ONLY:
+	    switch(sync_point_op) {
+                case H5AC_SYNC_POINT_OP__FLUSH_TO_MIN_CLEAN:
+	            if(H5AC__rsp__p0_only__flush_to_min_clean(f, dxpl_id) < 0)
+                        HGOTO_ERROR(H5E_CACHE, H5E_CANTGET, FAIL, "H5AC__rsp__p0_only__flush_to_min_clean() failed.")
+		    break;
+
+		case H5AC_SYNC_POINT_OP__FLUSH_CACHE:
+	            if(H5AC__rsp__p0_only__flush(f, dxpl_id) < 0)
+                        HGOTO_ERROR(H5E_CACHE, H5E_CANTGET, FAIL, "H5AC__rsp__p0_only__flush() failed.")
+		    break;
+
+		default:
+                    HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "unknown flush op");
+		    break;
+	    } /* end switch */
+	    break;
+
+	case H5AC_METADATA_WRITE_STRATEGY__DISTRIBUTED:
+	    switch(sync_point_op) {
+                case H5AC_SYNC_POINT_OP__FLUSH_TO_MIN_CLEAN:
+	            if(H5AC__rsp__dist_md_write__flush_to_min_clean(f, dxpl_id) < 0)
+                        HGOTO_ERROR(H5E_CACHE, H5E_CANTGET, FAIL, "H5AC__rsp__dist_md_write__flush_to_min_clean() failed.")
+		    break;
+
+		case H5AC_SYNC_POINT_OP__FLUSH_CACHE:
+	            if(H5AC__rsp__dist_md_write__flush(f, dxpl_id) < 0)
+                        HGOTO_ERROR(H5E_CACHE, H5E_CANTGET, FAIL, "H5AC__rsp__dist_md_write__flush() failed.")
+		    break;
+
+		default:
+                    HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "unknown flush op");
+		    break;
+	    } /* end switch */
+	    break;
+
+	default:
+            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Unknown metadata write strategy.")
+	    break;
+    } /* end switch */
+
+    /* reset the dirty bytes count */
+    aux_ptr->dirty_bytes = 0;
+
+#if H5AC_DEBUG_DIRTY_BYTES_CREATION
+    aux_ptr->dirty_bytes_propagations     += 1;
+    aux_ptr->unprotect_dirty_bytes         = 0;
+    aux_ptr->unprotect_dirty_bytes_updates = 0;
+    aux_ptr->insert_dirty_bytes            = 0;
+    aux_ptr->insert_dirty_bytes_updates    = 0;
+    aux_ptr->rename_dirty_bytes            = 0;
+    aux_ptr->rename_dirty_bytes_updates    = 0;
+#endif /* H5AC_DEBUG_DIRTY_BYTES_CREATION */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5AC__run_sync_point() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5AC__tidy_cache_0_lists()
+ *
+ * Purpose:     In the distributed metadata write strategy, not all dirty
+ *		entries are written by process 0 -- thus we must tidy
+ *		up the dirtied, and flushed and still clean lists 
+ *		maintained by process zero after each sync point.
+ *
+ *		This procedure exists to tend to this issue.
+ *
+ *		At this point, all entries that process 0 cleared should
+ *		have been removed from both the dirty and flushed and 
+ *		still clean lists, and entries that process 0 has flushed
+ *		should have been removed from the dirtied list and added
+ *		to the flushed and still clean list.
+ *
+ *		However, since the distributed metadata write strategy
+ *		doesn't make use of these lists, the objective is simply
+ *		to maintain these lists in consistent state that allows
+ *		them to be used should the metadata write strategy change
+ *		to one that uses these lists.
+ *
+ *		Thus for our purposes, all we need to do is remove from 
+ *		the dirtied and flushed and still clean lists all
+ *		references to entries that appear in the candidate list.
+ *
+ * Return:      Success:        non-negative
+ *
+ *              Failure:        negative
+ *
+ * Programmer:  John Mainzer
+ *              4/20/10
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5AC__tidy_cache_0_lists(H5AC_t *cache_ptr, int num_candidates,
+    haddr_t *candidates_list_ptr)
+{
+    H5AC_aux_t         * aux_ptr;
+    int                  i;
+
+    FUNC_ENTER_STATIC_NOERR
+
+    /* Sanity checks */
+    HDassert(cache_ptr != NULL);
+    aux_ptr = H5C_get_aux_ptr(cache_ptr);
+    HDassert(aux_ptr != NULL);
+    HDassert(aux_ptr->magic == H5AC__H5AC_AUX_T_MAGIC);
+    HDassert(aux_ptr->metadata_write_strategy == H5AC_METADATA_WRITE_STRATEGY__DISTRIBUTED);
+    HDassert(aux_ptr->mpi_rank == 0);
+    HDassert(num_candidates > 0);
+    HDassert(candidates_list_ptr != NULL);
+
+    /* clean up dirtied and flushed and still clean lists by removing 
+     * all entries on the candidate list.  Cleared entries should 
+     * have been removed from both the dirty and cleaned lists at 
+     * this point, flushed entries should have been added to the 
+     * cleaned list.  However, for this metadata write strategy, 
+     * we just want to remove all references to the candidate entries.
+     */
+    for(i = 0; i < num_candidates; i++) {
+        H5AC_slist_entry_t * d_slist_entry_ptr;
+        H5AC_slist_entry_t * c_slist_entry_ptr;
+        haddr_t              addr;
+
+        addr = candidates_list_ptr[i];
+
+        /* addr may be either on the dirtied list, or on the flushed 
+         * and still clean list.  Remove it.
+         */
+        if(NULL != (d_slist_entry_ptr = (H5AC_slist_entry_t *)H5SL_remove(aux_ptr->d_slist_ptr, (void *)&addr)))
+            d_slist_entry_ptr = H5FL_FREE(H5AC_slist_entry_t, d_slist_entry_ptr);
+        if(NULL != (c_slist_entry_ptr = (H5AC_slist_entry_t *)H5SL_remove(aux_ptr->c_slist_ptr, (void *)&addr)))
+            c_slist_entry_ptr = H5FL_FREE(H5AC_slist_entry_t, c_slist_entry_ptr);
+    } /* end for */
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* H5AC__tidy_cache_0_lists() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5AC__flush_entries
+ *
+ * Purpose:     Flush the metadata cache associated with the specified file,
+ *              only writing from rank 0, but propagating the cleaned entries
+ *              to all ranks.
+ *
+ * Return:      Non-negative on success/Negative on failure if there was a
+ *              request to flush all items and something was protected.
+ *
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              Aug 22 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5AC__flush_entries(H5F_t *f, hid_t dxpl_id)
+{
+    herr_t        ret_value = SUCCEED;      /* Return value */
+
+    FUNC_ENTER_PACKAGE
+
+    /* Sanity checks */
+    HDassert(f);
+    HDassert(f->shared->cache);
+
+    /* Check if we have >1 ranks */
+    if(H5C_get_aux_ptr(f->shared->cache))
+        if(H5AC__run_sync_point(f, dxpl_id, H5AC_SYNC_POINT_OP__FLUSH_CACHE) < 0)
+            HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "Can't run sync point.")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5AC__flush_entries() */
+#endif /* H5_HAVE_PARALLEL */
+
diff --git a/src/H5ACpkg.h b/src/H5ACpkg.h
index 950bdea..74bf079 100644
--- a/src/H5ACpkg.h
+++ b/src/H5ACpkg.h
@@ -41,8 +41,20 @@
 
 /* Get needed headers */
 #include "H5Cprivate.h"         /* Cache                                */
+#include "H5FLprivate.h"        /* Free Lists                           */
 #include "H5SLprivate.h"        /* Skip lists */
 
+/*****************************/
+/* Package Private Variables */
+/*****************************/
+
+/* Declare extern the free list to manage the H5AC_aux_t struct */
+H5FL_EXTERN(H5AC_aux_t);
+
+
+/**************************/
+/* Package Private Macros */
+/**************************/
 
 #define H5AC_DEBUG_DIRTY_BYTES_CREATION	0
 
@@ -392,6 +404,21 @@ typedef struct H5AC_aux_t
 
 } H5AC_aux_t; /* struct H5AC_aux_t */
 
+/* Package scoped functions */
+H5_DLL herr_t H5AC__log_deleted_entry(const H5AC_info_t *entry_ptr);
+H5_DLL herr_t H5AC__log_dirtied_entry(const H5AC_info_t *entry_ptr);
+H5_DLL herr_t H5AC__log_flushed_entry(H5C_t *cache_ptr, haddr_t addr,
+    hbool_t was_dirty, unsigned flags);
+H5_DLL herr_t H5AC__log_inserted_entry(const H5AC_info_t *entry_ptr);
+H5_DLL herr_t H5AC__log_moved_entry(const H5F_t *f, haddr_t old_addr,
+    haddr_t new_addr);
+H5_DLL herr_t H5AC__flush_entries(H5F_t *f, hid_t dxpl_id);
+H5_DLL herr_t H5AC__run_sync_point(H5F_t *f, hid_t dxpl_id, int sync_point_op);
+H5_DLL herr_t H5AC__set_sync_point_done_callback(H5C_t *cache_ptr,
+    void (*sync_point_done)(int num_writes, haddr_t *written_entries_tbl));
+H5_DLL herr_t H5AC__set_write_done_callback(H5C_t * cache_ptr,
+    void (* write_done)(void));
+
 #endif /* H5_HAVE_PARALLEL */
 
 #endif /* _H5ACpkg_H */
diff --git a/src/H5ACprivate.h b/src/H5ACprivate.h
index a4e7c5a..584ce9d 100644
--- a/src/H5ACprivate.h
+++ b/src/H5ACprivate.h
@@ -79,6 +79,7 @@ typedef enum {
     H5AC_FARRAY_DBLOCK_ID, /*fixed array data block	     	     */
     H5AC_FARRAY_DBLK_PAGE_ID, /*fixed array data block page          */
     H5AC_SUPERBLOCK_ID, /* file superblock                           */
+    H5AC_DRVRINFO_ID,   /* driver info block (supplements superblock)*/
     H5AC_TEST_ID,	/*test entry -- not used for actual files    */
     H5AC_NTYPES		/* Number of types, must be last             */
 } H5AC_type_t;
@@ -91,6 +92,17 @@ typedef enum {
  * times for debugging purposes.
  *
  * Hence the following, somewhat odd set of #defines.
+ *
+ * NOTE: test/cache plays games with the f->shared->cache, and thus 
+ *       setting H5AC_DUMP_STATS_ON_CLOSE will generate constant, 
+ *	 irrelevant data when run with that test program.  See 
+ * 	 comments on setup_cache() / takedown_cache() in test/cache_common.c.
+ *       for details.
+ *
+ *	 If you need to dump stats at file close in test/cache.c,
+ *	 use the dump_stats parameter to takedown_cache(), or call 
+ *	 H5C_stats() directly.
+ *					JRM -- 4/12/15
  */
 #if H5C_COLLECT_CACHE_STATS
 
@@ -113,81 +125,48 @@ typedef enum {
 /*
  * Class methods pertaining to caching.	 Each type of cached object will
  * have a constant variable with permanent life-span that describes how
- * to cache the object.	 That variable will be of type H5AC_class_t and
- * have the following required fields...
- *
- * LOAD:	Loads an object from disk to memory.  The function
- *		should allocate some data structure and return it.
- *
- * FLUSH:	Writes some data structure back to disk.  It would be
- *		wise for the data structure to include dirty flags to
- *		indicate whether it really needs to be written.	 This
- *		function is also responsible for freeing memory allocated
- *		by the LOAD method if the DEST argument is non-zero (by
- *              calling the DEST method).
- *
- * DEST:	Just frees memory allocated by the LOAD method.
- *
- * CLEAR:	Just marks object as non-dirty.
- *
- * NOTIFY:	Notify client that an action on an entry has taken/will take
- *              place
- *
- * SIZE:	Report the size (on disk) of the specified cache object.
- *		Note that the space allocated on disk may not be contiguous.
+ * to cache the object.
  */
 
-#define H5AC_CALLBACK__NO_FLAGS_SET             H5C_CALLBACK__NO_FLAGS_SET
-#define H5AC_CALLBACK__SIZE_CHANGED_FLAG	H5C_CALLBACK__SIZE_CHANGED_FLAG
-#define H5AC_CALLBACK__MOVED_FLAG             H5C_CALLBACK__MOVED_FLAG
+#define H5AC__SERIALIZE_RESIZED_FLAG	H5C__SERIALIZE_RESIZED_FLAG
+#define H5AC__SERIALIZE_MOVED_FLAG	H5C__SERIALIZE_MOVED_FLAG
+#define H5AC__SERIALIZE_COMPRESSED_FLAG	H5C__SERIALIZE_COMPRESSED_FLAG
 
 /* Aliases for 'notify action' type & values */
 typedef H5C_notify_action_t     H5AC_notify_action_t;
 #define H5AC_NOTIFY_ACTION_AFTER_INSERT H5C_NOTIFY_ACTION_AFTER_INSERT
+#define H5AC_NOTIFY_ACTION_AFTER_LOAD   H5C_NOTIFY_ACTION_AFTER_LOAD
+#define H5AC_NOTIFY_ACTION_AFTER_FLUSH	H5C_NOTIFY_ACTION_AFTER_FLUSH
 #define H5AC_NOTIFY_ACTION_BEFORE_EVICT H5C_NOTIFY_ACTION_BEFORE_EVICT
 
-typedef H5C_load_func_t		H5AC_load_func_t;
-typedef H5C_flush_func_t	H5AC_flush_func_t;
-typedef H5C_dest_func_t		H5AC_dest_func_t;
-typedef H5C_clear_func_t	H5AC_clear_func_t;
-typedef H5C_notify_func_t	H5AC_notify_func_t;
-typedef H5C_size_func_t		H5AC_size_func_t;
+#define H5AC__CLASS_NO_FLAGS_SET 	H5C__CLASS_NO_FLAGS_SET
+#define H5AC__CLASS_SPECULATIVE_LOAD_FLAG H5C__CLASS_SPECULATIVE_LOAD_FLAG
+#define H5AC__CLASS_COMPRESSED_FLAG	H5C__CLASS_COMPRESSED_FLAG
 
-typedef H5C_class_t			H5AC_class_t;
+/* The following flags should only appear in test code */
+#define H5AC__CLASS_NO_IO_FLAG		H5C__CLASS_NO_IO_FLAG
+#define H5AC__CLASS_SKIP_READS		H5C__CLASS_SKIP_READS
+#define H5AC__CLASS_SKIP_WRITES		H5C__CLASS_SKIP_WRITES
 
+typedef H5C_get_load_size_func_t	H5AC_get_load_size_func_t;
+typedef H5C_deserialize_func_t		H5AC_deserialize_func_t;
+typedef H5C_image_len_func_t		H5AC_image_len_func_t;
 
-/* The H5AC_NSLOTS #define is now obsolete, as the metadata cache no longer
- * uses slots.  However I am leaving it in for now to avoid modifying the
- * interface between the metadata cache and the rest of HDF.  It should
- * be removed when we get to dealing with the size_hint parameter in
- * H5AC_create().
- *						JRM - 5/20/04
- *
- * Old comment on H5AC_NSLOTS follows:
- *
- * A cache has a certain number of entries.  Objects are mapped into a
- * cache entry by hashing the object's file address.  Each file has its
- * own cache, an array of slots.
- */
-#define H5AC_NSLOTS     10330           /* The library "likes" this number... */
-
-
-typedef H5C_cache_entry_t		H5AC_info_t;
+#define H5AC__SERIALIZE_NO_FLAGS_SET    H5C__SERIALIZE_NO_FLAGS_SET
+#define H5AC__SERIALIZE_RESIZED_FLAG    H5C__SERIALIZE_RESIZED_FLAG
+#define H5AC__SERIALIZE_MOVED_FLAG      H5C__SERIALIZE_MOVED_FLAG
 
+typedef H5C_pre_serialize_func_t	H5AC_pre_serialize_func_t;
+typedef H5C_serialize_func_t		H5AC_serialize_func_t;
+typedef H5C_notify_func_t		H5AC_notify_func_t;
+typedef H5C_free_icr_func_t		H5AC_free_icr_func_t;
+typedef H5C_clear_func_t		H5AC_clear_func_t;
+typedef H5C_get_fsf_size_t		H5AC_get_fsf_size_t;
 
-/*===----------------------------------------------------------------------===
- *                             Protect Types
- *===----------------------------------------------------------------------===
- *
- * These are for the wrapper functions to H5AC_protect. They specify what
- * type of operation you're planning on doing to the metadata. The
- * Flexible Parallel HDF5 locking can then act accordingly.
- */
+typedef H5C_class_t			H5AC_class_t;
 
-typedef enum H5AC_protect_t {
-    H5AC_WRITE,                 /* Protect object for writing                */
-    H5AC_READ                   /* Protect object for reading                */
-} H5AC_protect_t;
+/* Cache entry info */
+typedef H5C_cache_entry_t		H5AC_info_t;
 
 
 /* Typedef for metadata cache (defined in H5Cpkg.h) */
@@ -317,6 +296,7 @@ H5_DLLVAR hid_t H5AC_ind_dxpl_id;
 #define H5AC__FLUSH_CLEAR_ONLY_FLAG	  H5C__FLUSH_CLEAR_ONLY_FLAG
 #define H5AC__FLUSH_MARKED_ENTRIES_FLAG   H5C__FLUSH_MARKED_ENTRIES_FLAG
 #define H5AC__FLUSH_IGNORE_PROTECTED_FLAG H5C__FLUSH_IGNORE_PROTECTED_FLAG
+#define H5AC__READ_ONLY_FLAG		  H5C__READ_ONLY_FLAG
 #define H5AC__FREE_FILE_SPACE_FLAG	  H5C__FREE_FILE_SPACE_FLAG
 #define H5AC__TAKE_OWNERSHIP_FLAG         H5C__TAKE_OWNERSHIP_FLAG
 #define H5AC__FLUSH_LAST_FLAG		  H5C__FLUSH_LAST_FLAG
@@ -346,7 +326,7 @@ H5_DLL herr_t H5AC_insert_entry(H5F_t *f, hid_t dxpl_id, const H5AC_class_t *typ
 H5_DLL herr_t H5AC_pin_protected_entry(void *thing);
 H5_DLL herr_t H5AC_create_flush_dependency(void *parent_thing, void *child_thing);
 H5_DLL void * H5AC_protect(H5F_t *f, hid_t dxpl_id, const H5AC_class_t *type,
-    haddr_t addr, void *udata, H5AC_protect_t rw);
+    haddr_t addr, void *udata, unsigned flags);
 H5_DLL herr_t H5AC_resize_entry(void *thing, size_t new_size);
 H5_DLL herr_t H5AC_unpin_entry(void *thing);
 H5_DLL herr_t H5AC_destroy_flush_dependency(void *parent_thing, void *child_thing);
@@ -359,10 +339,6 @@ H5_DLL herr_t H5AC_move_entry(H5F_t *f, const H5AC_class_t *type,
 H5_DLL herr_t H5AC_dest(H5F_t *f, hid_t dxpl_id);
 H5_DLL herr_t H5AC_expunge_entry(H5F_t *f, hid_t dxpl_id,
     const H5AC_class_t *type, haddr_t addr, unsigned flags);
-H5_DLL herr_t H5AC_set_sync_point_done_callback(H5C_t *cache_ptr,
-    void (*sync_point_done)(int num_writes, haddr_t *written_entries_tbl));
-H5_DLL herr_t H5AC_set_write_done_callback(H5C_t * cache_ptr,
-                                           void (* write_done)(void));
 H5_DLL herr_t H5AC_get_cache_auto_resize_config(const H5AC_t * cache_ptr,
     H5AC_cache_config_t *config_ptr);
 H5_DLL herr_t H5AC_get_cache_size(H5AC_t *cache_ptr, size_t *max_size_ptr,
diff --git a/src/H5B.c b/src/H5B.c
index 765a57e..b1f3388 100644
--- a/src/H5B.c
+++ b/src/H5B.c
@@ -336,7 +336,7 @@ H5B_find(H5F_t *f, hid_t dxpl_id, const H5B_class_t *type, haddr_t addr, void *u
     cache_udata.f = f;
     cache_udata.type = type;
     cache_udata.rc_shared = rc_shared;
-    if(NULL == (bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, addr, &cache_udata, H5AC_READ)))
+    if(NULL == (bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, addr, &cache_udata, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to load B-tree node")
 
     rt = bt->nchildren;
@@ -485,7 +485,7 @@ H5B__split(H5F_t *f, hid_t dxpl_id, H5B_ins_ud_t *bt_ud, unsigned idx,
     cache_udata.f = f;
     cache_udata.type = shared->type;
     cache_udata.rc_shared = bt_ud->bt->rc_shared;
-    if(NULL == (split_bt_ud->bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, split_bt_ud->addr, &cache_udata, H5AC_WRITE)))
+    if(NULL == (split_bt_ud->bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, split_bt_ud->addr, &cache_udata, H5AC__NO_FLAGS_SET)))
 	HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree")
     split_bt_ud->bt->level = bt_ud->bt->level;
 
@@ -518,7 +518,7 @@ H5B__split(H5F_t *f, hid_t dxpl_id, H5B_ins_ud_t *bt_ud, unsigned idx,
     if(H5F_addr_defined(bt_ud->bt->right)) {
         H5B_t   *tmp_bt;
 
-        if(NULL == (tmp_bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, bt_ud->bt->right, &cache_udata, H5AC_WRITE)))
+        if(NULL == (tmp_bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, bt_ud->bt->right, &cache_udata, H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to load right sibling")
 
         tmp_bt->left = split_bt_ud->addr;
@@ -597,7 +597,7 @@ H5B_insert(H5F_t *f, hid_t dxpl_id, const H5B_class_t *type, haddr_t addr, void
     cache_udata.type = type;
     cache_udata.rc_shared = rc_shared;
     bt_ud.addr = addr;
-    if(NULL == (bt_ud.bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, addr, &cache_udata, H5AC_WRITE)))
+    if(NULL == (bt_ud.bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, addr, &cache_udata, H5AC__NO_FLAGS_SET)))
         HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to locate root of B-tree")
 
     /* Insert the object */
@@ -901,7 +901,7 @@ H5B__insert_helper(H5F_t *f, hid_t dxpl_id, H5B_ins_ud_t *bt_ud,
              * Follow the minimum branch out of this node to a subtree.
              */
             child_bt_ud.addr = bt->child[idx];
-            if(NULL == (child_bt_ud.bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, child_bt_ud.addr, &cache_udata, H5AC_WRITE)))
+            if(NULL == (child_bt_ud.bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, child_bt_ud.addr, &cache_udata, H5AC__NO_FLAGS_SET)))
                 HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, H5B_INS_ERROR, "unable to load node")
 
             if((int)(my_ins = H5B__insert_helper(f, dxpl_id, &child_bt_ud, type,
@@ -947,7 +947,7 @@ H5B__insert_helper(H5F_t *f, hid_t dxpl_id, H5B_ins_ud_t *bt_ud,
             */
             idx = bt->nchildren - 1;
             child_bt_ud.addr = bt->child[idx];
-            if(NULL == (child_bt_ud.bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, child_bt_ud.addr, &cache_udata, H5AC_WRITE)))
+            if(NULL == (child_bt_ud.bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, child_bt_ud.addr, &cache_udata, H5AC__NO_FLAGS_SET)))
                 HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, H5B_INS_ERROR, "unable to load node")
 
             if((int)(my_ins = H5B__insert_helper(f, dxpl_id, &child_bt_ud, type,
@@ -1002,7 +1002,7 @@ H5B__insert_helper(H5F_t *f, hid_t dxpl_id, H5B_ins_ud_t *bt_ud,
 	 */
 	HDassert(idx < bt->nchildren);
 	child_bt_ud.addr = bt->child[idx];
-        if(NULL == (child_bt_ud.bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, child_bt_ud.addr, &cache_udata, H5AC_WRITE)))
+        if(NULL == (child_bt_ud.bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, child_bt_ud.addr, &cache_udata, H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, H5B_INS_ERROR, "unable to load node")
 
 	if((int)(my_ins = H5B__insert_helper(f, dxpl_id, &child_bt_ud, type,
@@ -1164,7 +1164,7 @@ H5B__iterate_helper(H5F_t *f, hid_t dxpl_id, const H5B_class_t *type, haddr_t ad
     cache_udata.f = f;
     cache_udata.type = type;
     cache_udata.rc_shared = rc_shared;
-    if(NULL == (bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, addr, &cache_udata, H5AC_READ)))
+    if(NULL == (bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, addr, &cache_udata, H5AC__READ_ONLY_FLAG)))
         HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, H5_ITER_ERROR, "unable to load B-tree node")
 
     /* Iterate over node's children */
@@ -1287,7 +1287,7 @@ H5B__remove_helper(H5F_t *f, hid_t dxpl_id, haddr_t addr, const H5B_class_t *typ
     cache_udata.f = f;
     cache_udata.type = type;
     cache_udata.rc_shared = rc_shared;
-    if(NULL == (bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, addr, &cache_udata, H5AC_WRITE)))
+    if(NULL == (bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, addr, &cache_udata, H5AC__NO_FLAGS_SET)))
 	HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, H5B_INS_ERROR, "unable to load B-tree node")
 
     rt = bt->nchildren;
@@ -1387,7 +1387,7 @@ H5B__remove_helper(H5F_t *f, hid_t dxpl_id, haddr_t addr, const H5B_class_t *typ
                  * "critical" for any child in its node to maintain this
                  * consistency (and avoid breaking key/child consistency) */
                 if(H5F_addr_defined(bt->left)) {
-                    if(NULL == (sibling = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, bt->left, &cache_udata, H5AC_WRITE)))
+                    if(NULL == (sibling = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, bt->left, &cache_udata, H5AC__NO_FLAGS_SET)))
                         HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, H5B_INS_ERROR, "unable to load node from tree")
 
                     /* Copy right-most key from deleted node to right-most key
@@ -1404,7 +1404,7 @@ H5B__remove_helper(H5F_t *f, hid_t dxpl_id, haddr_t addr, const H5B_class_t *typ
                     sibling = NULL;   /* Make certain future references will be caught */
                 } /* end if */
                 if(H5F_addr_defined(bt->right)) {
-                    if(NULL == (sibling = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, bt->right, &cache_udata, H5AC_WRITE)))
+                    if(NULL == (sibling = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, bt->right, &cache_udata, H5AC__NO_FLAGS_SET)))
                         HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, H5B_INS_ERROR, "unable to unlink node from tree")
 
                     /* Copy left-most key from deleted node to left-most key in
@@ -1524,7 +1524,7 @@ H5B__remove_helper(H5F_t *f, hid_t dxpl_id, haddr_t addr, const H5B_class_t *typ
         HDassert(level > 0);
 
         /* Update the rightmost key in the left sibling */
-        if(NULL == (sibling = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, bt->left, &cache_udata, H5AC_WRITE)))
+        if(NULL == (sibling = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, bt->left, &cache_udata, H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, H5B_INS_ERROR, "unable to protect node")
 
         HDmemcpy(H5B_NKEY(sibling, shared, sibling->nchildren),
@@ -1539,7 +1539,7 @@ H5B__remove_helper(H5F_t *f, hid_t dxpl_id, haddr_t addr, const H5B_class_t *typ
         HDassert(level > 0);
 
         /* Update the lefttmost key in the right sibling */
-        if(NULL == (sibling = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, bt->right, &cache_udata, H5AC_WRITE)))
+        if(NULL == (sibling = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, bt->right, &cache_udata, H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, H5B_INS_ERROR, "unable to protect node")
 
         HDmemcpy(H5B_NKEY(sibling, shared, 0),
@@ -1646,7 +1646,7 @@ H5B_delete(H5F_t *f, hid_t dxpl_id, const H5B_class_t *type, haddr_t addr, void
     cache_udata.f = f;
     cache_udata.type = type;
     cache_udata.rc_shared = rc_shared;
-    if(NULL == (bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, addr, &cache_udata, H5AC_WRITE)))
+    if(NULL == (bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, addr, &cache_udata, H5AC__NO_FLAGS_SET)))
         HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to load B-tree node")
 
     /* Iterate over all children in tree, deleting them */
@@ -1908,7 +1908,7 @@ H5B__get_info_helper(H5F_t *f, hid_t dxpl_id, const H5B_class_t *type, haddr_t a
     cache_udata.f = f;
     cache_udata.type = type;
     cache_udata.rc_shared = rc_shared;
-    if(NULL == (bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, addr, &cache_udata, H5AC_READ)))
+    if(NULL == (bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, addr, &cache_udata, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to load B-tree node")
 
     /* Cache information from this node */
@@ -1932,7 +1932,7 @@ H5B__get_info_helper(H5F_t *f, hid_t dxpl_id, const H5B_class_t *type, haddr_t a
     while(H5F_addr_defined(next_addr)) {
         /* Protect the next node to the right */
         addr = next_addr;
-        if(NULL == (bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, addr, &cache_udata, H5AC_READ)))
+        if(NULL == (bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, addr, &cache_udata, H5AC__READ_ONLY_FLAG)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "B-tree node")
 
         /* Cache information from this node */
@@ -2059,7 +2059,7 @@ H5B_valid(H5F_t *f, hid_t dxpl_id, const H5B_class_t *type, haddr_t addr)
     cache_udata.f = f;
     cache_udata.type = type;
     cache_udata.rc_shared = rc_shared;
-    if(NULL == (bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, addr, &cache_udata, H5AC_READ)))
+    if(NULL == (bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, addr, &cache_udata, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree node")
 
 done:
diff --git a/src/H5B2.c b/src/H5B2.c
index 0c0f24f..7b5aa16 100644
--- a/src/H5B2.c
+++ b/src/H5B2.c
@@ -155,8 +155,9 @@ H5B2_create(H5F_t *f, hid_t dxpl_id, const H5B2_create_t *cparam, void *ctx_udat
 
     /* Look up the B-tree header */
     cache_udata.f = f;
+    cache_udata.addr = hdr_addr;
     cache_udata.ctx_udata = ctx_udata;
-    if(NULL == (hdr = (H5B2_hdr_t *)H5AC_protect(f, dxpl_id, H5AC_BT2_HDR, hdr_addr, &cache_udata, H5AC_WRITE)))
+    if(NULL == (hdr = (H5B2_hdr_t *)H5AC_protect(f, dxpl_id, H5AC_BT2_HDR, hdr_addr, &cache_udata, H5AC__NO_FLAGS_SET)))
         HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, NULL, "unable to load B-tree header")
 
     /* Point v2 B-tree wrapper at header and bump it's ref count */
@@ -215,8 +216,9 @@ H5B2_open(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *ctx_udata)
 
     /* Look up the B-tree header */
     cache_udata.f = f;
+    cache_udata.addr = addr;
     cache_udata.ctx_udata = ctx_udata;
-    if(NULL == (hdr = (H5B2_hdr_t *)H5AC_protect(f, dxpl_id, H5AC_BT2_HDR, addr, &cache_udata, H5AC_READ)))
+    if(NULL == (hdr = (H5B2_hdr_t *)H5AC_protect(f, dxpl_id, H5AC_BT2_HDR, addr, &cache_udata, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, NULL, "unable to load B-tree header")
 
     /* Check for pending heap deletion */
@@ -479,7 +481,7 @@ H5B2_find(H5B2_t *bt2, hid_t dxpl_id, void *udata, H5B2_found_t op,
         H5B2_node_ptr_t next_node_ptr;      /* Node pointer info for next node */
 
         /* Lock B-tree current node */
-        if(NULL == (internal = H5B2__protect_internal(hdr, dxpl_id, curr_node_ptr.addr, curr_node_ptr.node_nrec, depth, H5AC_READ)))
+        if(NULL == (internal = H5B2__protect_internal(hdr, dxpl_id, curr_node_ptr.addr, curr_node_ptr.node_nrec, depth, H5AC__READ_ONLY_FLAG)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to load B-tree internal node")
 
         /* Locate node pointer for child */
@@ -542,7 +544,7 @@ H5B2_find(H5B2_t *bt2, hid_t dxpl_id, void *udata, H5B2_found_t op,
         H5B2_leaf_t *leaf;          /* Pointer to leaf node in B-tree */
 
         /* Lock B-tree leaf node */
-        if(NULL == (leaf = H5B2__protect_leaf(hdr, dxpl_id, curr_node_ptr.addr, curr_node_ptr.node_nrec, H5AC_READ)))
+        if(NULL == (leaf = H5B2__protect_leaf(hdr, dxpl_id, curr_node_ptr.addr, curr_node_ptr.node_nrec, H5AC__READ_ONLY_FLAG)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree leaf node")
 
         /* Locate record */
@@ -662,7 +664,7 @@ H5B2_index(H5B2_t *bt2, hid_t dxpl_id, H5_iter_order_t order, hsize_t idx,
         unsigned u;                         /* Local index variable */
 
         /* Lock B-tree current node */
-        if(NULL == (internal = H5B2__protect_internal(hdr, dxpl_id, curr_node_ptr.addr, curr_node_ptr.node_nrec, depth, H5AC_READ)))
+        if(NULL == (internal = H5B2__protect_internal(hdr, dxpl_id, curr_node_ptr.addr, curr_node_ptr.node_nrec, depth, H5AC__READ_ONLY_FLAG)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to load B-tree internal node")
 
         /* Search for record with correct index */
@@ -734,7 +736,7 @@ H5B2_index(H5B2_t *bt2, hid_t dxpl_id, H5_iter_order_t order, hsize_t idx,
         H5B2_leaf_t *leaf;          /* Pointer to leaf node in B-tree */
 
         /* Lock B-tree leaf node */
-        if(NULL == (leaf = H5B2__protect_leaf(hdr, dxpl_id, curr_node_ptr.addr, curr_node_ptr.node_nrec, H5AC_READ)))
+        if(NULL == (leaf = H5B2__protect_leaf(hdr, dxpl_id, curr_node_ptr.addr, curr_node_ptr.node_nrec, H5AC__READ_ONLY_FLAG)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree leaf node")
 
         /* Sanity check index */
@@ -1070,7 +1072,7 @@ H5B2_modify(H5B2_t *bt2, hid_t dxpl_id, void *udata, H5B2_modify_t op,
         H5B2_node_ptr_t next_node_ptr;      /* Node pointer info for next node */
 
         /* Lock B-tree current node */
-        if(NULL == (internal = H5B2__protect_internal(hdr, dxpl_id, curr_node_ptr.addr, curr_node_ptr.node_nrec, depth, H5AC_WRITE)))
+        if(NULL == (internal = H5B2__protect_internal(hdr, dxpl_id, curr_node_ptr.addr, curr_node_ptr.node_nrec, depth, H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to load B-tree internal node")
 
         /* Locate node pointer for child */
@@ -1142,7 +1144,7 @@ H5B2_modify(H5B2_t *bt2, hid_t dxpl_id, void *udata, H5B2_modify_t op,
         hbool_t changed = FALSE;/* Whether the 'modify' callback changed the record */
 
         /* Lock B-tree leaf node */
-        if(NULL == (leaf = H5B2__protect_leaf(hdr, dxpl_id, curr_node_ptr.addr, curr_node_ptr.node_nrec, H5AC_WRITE)))
+        if(NULL == (leaf = H5B2__protect_leaf(hdr, dxpl_id, curr_node_ptr.addr, curr_node_ptr.node_nrec, H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree leaf node")
 
         /* Locate record */
@@ -1276,7 +1278,7 @@ H5B2_close(H5B2_t *bt2, hid_t dxpl_id)
 
         /* Lock the v2 B-tree header into memory */
         /* (OK to pass in NULL for callback context, since we know the header must be in the cache) */
-        if(NULL == (hdr = (H5B2_hdr_t *)H5AC_protect(bt2->f, dxpl_id, H5AC_BT2_HDR, bt2_addr, NULL, H5AC_WRITE)))
+        if(NULL == (hdr = (H5B2_hdr_t *)H5AC_protect(bt2->f, dxpl_id, H5AC_BT2_HDR, bt2_addr, NULL, H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect v2 B-tree header")
 
         /* Set the shared v2 B-tree header's file context for this operation */
@@ -1352,8 +1354,9 @@ H5B2_delete(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *ctx_udata,
 HDfprintf(stderr, "%s: addr = %a\n", FUNC, addr);
 #endif /* QAK */
     cache_udata.f = f;
+    cache_udata.addr = addr;
     cache_udata.ctx_udata = ctx_udata;
-    if(NULL == (hdr = (H5B2_hdr_t *)H5AC_protect(f, dxpl_id, H5AC_BT2_HDR, addr, &cache_udata, H5AC_WRITE)))
+    if(NULL == (hdr = (H5B2_hdr_t *)H5AC_protect(f, dxpl_id, H5AC_BT2_HDR, addr, &cache_udata, H5AC__NO_FLAGS_SET)))
         HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect v2 B-tree header")
 
     /* Remember the callback & context for later */
diff --git a/src/H5B2cache.c b/src/H5B2cache.c
index 3b30e02..9e43ff8 100644
--- a/src/H5B2cache.c
+++ b/src/H5B2cache.c
@@ -37,7 +37,6 @@
 #include "H5private.h"		/* Generic Functions			*/
 #include "H5B2pkg.h"		/* v2 B-trees				*/
 #include "H5Eprivate.h"		/* Error handling		  	*/
-#include "H5MFprivate.h"	/* File memory management		*/
 #include "H5WBprivate.h"        /* Wrapped Buffers                      */
 
 
@@ -50,9 +49,6 @@
 #define H5B2_INT_VERSION 0              /* Internal node */
 #define H5B2_LEAF_VERSION 0             /* Leaf node */
 
-/* Size of stack buffer for serialized headers */
-#define H5B2_HDR_BUF_SIZE               128
-
 
 /******************/
 /* Local Typedefs */
@@ -69,22 +65,32 @@
 /********************/
 
 /* Metadata cache callbacks */
-static H5B2_hdr_t *H5B2__cache_hdr_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata);
-static herr_t H5B2__cache_hdr_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5B2_hdr_t *hdr, unsigned H5_ATTR_UNUSED * flags_ptr);
-static herr_t H5B2__cache_hdr_dest(H5F_t *f, H5B2_hdr_t *hdr);
-static herr_t H5B2__cache_hdr_clear(H5F_t *f, H5B2_hdr_t *hdr, hbool_t destroy);
-static herr_t H5B2__cache_hdr_size(const H5F_t *f, const H5B2_hdr_t *hdr, size_t *size_ptr);
-static H5B2_internal_t *H5B2__cache_internal_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata);
-static herr_t H5B2__cache_internal_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5B2_internal_t *i, unsigned H5_ATTR_UNUSED * flags_ptr);
-static herr_t H5B2__cache_internal_dest(H5F_t *f, H5B2_internal_t *internal);
-static herr_t H5B2__cache_internal_clear(H5F_t *f, H5B2_internal_t *i, hbool_t destroy);
-static herr_t H5B2__cache_internal_size(const H5F_t *f, const H5B2_internal_t *i, size_t *size_ptr);
-static H5B2_leaf_t *H5B2__cache_leaf_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata);
-static herr_t H5B2__cache_leaf_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5B2_leaf_t *l, unsigned H5_ATTR_UNUSED * flags_ptr);
-static herr_t H5B2__cache_leaf_dest(H5F_t *f, H5B2_leaf_t *leaf);
-static herr_t H5B2__cache_leaf_clear(H5F_t *f, H5B2_leaf_t *l, hbool_t destroy);
-static herr_t H5B2__cache_leaf_size(const H5F_t *f, const H5B2_leaf_t *l, size_t *size_ptr);
-
+static herr_t H5B2__cache_hdr_get_load_size(const void *udata, size_t *image_len);
+static void *H5B2__cache_hdr_deserialize(const void *image, size_t len,
+    void *udata, hbool_t *dirty);
+static herr_t H5B2__cache_hdr_image_len(const void *thing, size_t *image_len,
+    hbool_t *compressed_ptr, size_t *compressed_image_len_ptr);
+static herr_t H5B2__cache_hdr_serialize(const H5F_t *f, void *image, size_t len,
+    void *thing);
+static herr_t H5B2__cache_hdr_free_icr(void *thing);
+
+static herr_t H5B2__cache_int_get_load_size(const void *udata, size_t *image_len);
+static void *H5B2__cache_int_deserialize(const void *image, size_t len,
+    void *udata, hbool_t *dirty);
+static herr_t H5B2__cache_int_image_len(const void *thing, size_t *image_len,
+    hbool_t *compressed_ptr, size_t *compressed_image_len_ptr);
+static herr_t H5B2__cache_int_serialize(const H5F_t *f, void *image, size_t len,
+    void *thing);
+static herr_t H5B2__cache_int_free_icr(void *thing);
+
+static herr_t H5B2__cache_leaf_get_load_size(const void *udata, size_t *image_len);
+static void *H5B2__cache_leaf_deserialize(const void *image, size_t len,
+    void *udata, hbool_t *dirty);
+static herr_t H5B2__cache_leaf_image_len(const void *thing, size_t *image_len,
+    hbool_t *compressed_ptr, size_t *compressed_image_len_ptr);
+static herr_t H5B2__cache_leaf_serialize(const H5F_t *f, void *image, size_t len,
+    void *thing);
+static herr_t H5B2__cache_leaf_free_icr(void *thing);
 
 /*********************/
 /* Package Variables */
@@ -92,35 +98,53 @@ static herr_t H5B2__cache_leaf_size(const H5F_t *f, const H5B2_leaf_t *l, size_t
 
 /* H5B2 inherits cache-like properties from H5AC */
 const H5AC_class_t H5AC_BT2_HDR[1] = {{
-    H5AC_BT2_HDR_ID,
-    (H5AC_load_func_t)H5B2__cache_hdr_load,
-    (H5AC_flush_func_t)H5B2__cache_hdr_flush,
-    (H5AC_dest_func_t)H5B2__cache_hdr_dest,
-    (H5AC_clear_func_t)H5B2__cache_hdr_clear,
-    (H5AC_notify_func_t)NULL,
-    (H5AC_size_func_t)H5B2__cache_hdr_size,
+    H5AC_BT2_HDR_ID,                    /* Metadata client ID */
+    "v2 B-tree header",                 /* Metadata client name (for debugging) */
+    H5FD_MEM_BTREE,                     /* File space memory type for client */
+    H5AC__CLASS_NO_FLAGS_SET,           /* Client class behavior flags */
+    H5B2__cache_hdr_get_load_size,      /* 'get_load_size' callback */
+    H5B2__cache_hdr_deserialize,        /* 'deserialize' callback */
+    H5B2__cache_hdr_image_len,          /* 'image_len' callback */
+    NULL,                               /* 'pre_serialize' callback */
+    H5B2__cache_hdr_serialize,          /* 'serialize' callback */
+    NULL,                               /* 'notify' callback */
+    H5B2__cache_hdr_free_icr,           /* 'free_icr' callback */
+    NULL,				/* 'clear' callback */
+    NULL,				/* 'fsf_size' callback */
 }};
 
 /* H5B2 inherits cache-like properties from H5AC */
 const H5AC_class_t H5AC_BT2_INT[1] = {{
-    H5AC_BT2_INT_ID,
-    (H5AC_load_func_t)H5B2__cache_internal_load,
-    (H5AC_flush_func_t)H5B2__cache_internal_flush,
-    (H5AC_dest_func_t)H5B2__cache_internal_dest,
-    (H5AC_clear_func_t)H5B2__cache_internal_clear,
-    (H5AC_notify_func_t)NULL,
-    (H5AC_size_func_t)H5B2__cache_internal_size,
+    H5AC_BT2_INT_ID,                    /* Metadata client ID */
+    "v2 B-tree internal node",          /* Metadata client name (for debugging) */
+    H5FD_MEM_BTREE,                     /* File space memory type for client */
+    H5AC__CLASS_NO_FLAGS_SET,           /* Client class behavior flags */
+    H5B2__cache_int_get_load_size,      /* 'get_load_size' callback */
+    H5B2__cache_int_deserialize,        /* 'deserialize' callback */
+    H5B2__cache_int_image_len,          /* 'image_len' callback */
+    NULL,                               /* 'pre_serialize' callback */
+    H5B2__cache_int_serialize,          /* 'serialize' callback */
+    NULL,                               /* 'notify' callback */
+    H5B2__cache_int_free_icr,           /* 'free_icr' callback */
+    NULL,				/* 'clear' callback */
+    NULL,				/* 'fsf_size' callback */
 }};
 
 /* H5B2 inherits cache-like properties from H5AC */
 const H5AC_class_t H5AC_BT2_LEAF[1] = {{
-    H5AC_BT2_LEAF_ID,
-    (H5AC_load_func_t)H5B2__cache_leaf_load,
-    (H5AC_flush_func_t)H5B2__cache_leaf_flush,
-    (H5AC_dest_func_t)H5B2__cache_leaf_dest,
-    (H5AC_clear_func_t)H5B2__cache_leaf_clear,
-    (H5AC_notify_func_t)NULL,
-    (H5AC_size_func_t)H5B2__cache_leaf_size,
+    H5AC_BT2_LEAF_ID,                   /* Metadata client ID */
+    "v2 B-tree leaf node",              /* Metadata client name (for debugging) */
+    H5FD_MEM_BTREE,                     /* File space memory type for client */
+    H5AC__CLASS_NO_FLAGS_SET,           /* Client class behavior flags */
+    H5B2__cache_leaf_get_load_size,     /* 'get_load_size' callback */
+    H5B2__cache_leaf_deserialize,       /* 'deserialize' callback */
+    H5B2__cache_leaf_image_len,         /* 'image_len' callback */
+    NULL,                               /* 'pre_serialize' callback */
+    H5B2__cache_leaf_serialize,         /* 'serialize' callback */
+    NULL,                               /* 'notify' callback */
+    H5B2__cache_leaf_free_icr,          /* 'free_icr' callback */
+    NULL,				/* 'clear' callback */
+    NULL,				/* 'fsf_size' callback */
 }};
 
 
@@ -136,7 +160,38 @@ const H5AC_class_t H5AC_BT2_LEAF[1] = {{
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5B2__cache_hdr_load
+ * Function:    H5B2__cache_hdr_get_load_size
+ *
+ * Purpose:     Compute the size of the data structure on disk.
+ *
+ * Return:      Non-negative on success/Negative on failure
+ *
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              May 18, 2010
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5B2__cache_hdr_get_load_size(const void *_udata, size_t *image_len)
+{
+    const H5B2_hdr_cache_ud_t *udata = (const H5B2_hdr_cache_ud_t *)_udata; /* User data for callback */
+
+    FUNC_ENTER_STATIC_NOERR
+
+    /* Check arguments */
+    HDassert(udata);
+    HDassert(image_len);
+
+    /* Set the image length size */
+    *image_len = H5B2_HEADER_SIZE_FILE(udata->f);
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5B2__cache_hdr_get_load_size() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5B2__cache_hdr_deserialize
  *
  * Purpose:	Loads a B-tree header from the disk.
  *
@@ -149,8 +204,9 @@ const H5AC_class_t H5AC_BT2_LEAF[1] = {{
  *
  *-------------------------------------------------------------------------
  */
-static H5B2_hdr_t *
-H5B2__cache_hdr_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
+static void *
+H5B2__cache_hdr_deserialize(const void *_image, size_t H5_ATTR_UNUSED len,
+    void *_udata, hbool_t H5_ATTR_UNUSED *dirty)
 {
     H5B2_hdr_t		*hdr = NULL;    /* B-tree header */
     H5B2_hdr_cache_ud_t *udata = (H5B2_hdr_cache_ud_t *)_udata;
@@ -159,78 +215,59 @@ H5B2__cache_hdr_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
     uint16_t            depth;          /* Depth of B-tree */
     uint32_t            stored_chksum;  /* Stored metadata checksum value */
     uint32_t            computed_chksum; /* Computed metadata checksum value */
-    H5WB_t              *wb = NULL;     /* Wrapped buffer for header data */
-    uint8_t             hdr_buf[H5B2_HDR_BUF_SIZE]; /* Buffer for header */
-    uint8_t		*buf;           /* Pointer to header buffer */
-    const uint8_t	*p;             /* Pointer into raw data buffer */
+    const uint8_t	*image = (const uint8_t *)_image;       /* Pointer into raw data buffer */
     H5B2_hdr_t		*ret_value;     /* Return value */
 
     FUNC_ENTER_STATIC
 
     /* Check arguments */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
+    HDassert(image);
     HDassert(udata);
 
     /* Allocate new B-tree header and reset cache info */
     if(NULL == (hdr = H5B2__hdr_alloc(udata->f)))
         HGOTO_ERROR(H5E_BTREE, H5E_CANTALLOC, NULL, "allocation failed for B-tree header")
 
-    /* Wrap the local buffer for serialized header info */
-    if(NULL == (wb = H5WB_wrap(hdr_buf, sizeof(hdr_buf))))
-        HGOTO_ERROR(H5E_BTREE, H5E_CANTINIT, NULL, "can't wrap buffer")
-
-    /* Get a pointer to a buffer that's large enough for header */
-    if(NULL == (buf = (uint8_t *)H5WB_actual(wb, hdr->hdr_size)))
-        HGOTO_ERROR(H5E_BTREE, H5E_NOSPACE, NULL, "can't get actual buffer")
-
-    /* Read header from disk */
-    if(H5F_block_read(f, H5FD_MEM_BTREE, addr, hdr->hdr_size, dxpl_id, buf) < 0)
-        HGOTO_ERROR(H5E_BTREE, H5E_READERROR, NULL, "can't read B-tree header")
-
-    /* Get temporary pointer to serialized header */
-    p = buf;
-
     /* Magic number */
-    if(HDmemcmp(p, H5B2_HDR_MAGIC, (size_t)H5_SIZEOF_MAGIC))
+    if(HDmemcmp(image, H5B2_HDR_MAGIC, (size_t)H5_SIZEOF_MAGIC))
 	HGOTO_ERROR(H5E_BTREE, H5E_BADVALUE, NULL, "wrong B-tree header signature")
-    p += H5_SIZEOF_MAGIC;
+    image += H5_SIZEOF_MAGIC;
 
     /* Version */
-    if(*p++ != H5B2_HDR_VERSION)
+    if(*image++ != H5B2_HDR_VERSION)
 	HGOTO_ERROR(H5E_BTREE, H5E_BADRANGE, NULL, "wrong B-tree header version")
 
     /* B-tree class */
-    id = (H5B2_subid_t)*p++;
+    id = (H5B2_subid_t)*image++;
     if(id >= H5B2_NUM_BTREE_ID)
         HGOTO_ERROR(H5E_BTREE, H5E_BADTYPE, NULL, "incorrect B-tree type")
 
     /* Node size (in bytes) */
-    UINT32DECODE(p, cparam.node_size);
+    UINT32DECODE(image, cparam.node_size);
 
     /* Raw key size (in bytes) */
-    UINT16DECODE(p, cparam.rrec_size);
+    UINT16DECODE(image, cparam.rrec_size);
 
     /* Depth of tree */
-    UINT16DECODE(p, depth);
+    UINT16DECODE(image, depth);
 
     /* Split & merge %s */
-    cparam.split_percent = *p++;
-    cparam.merge_percent = *p++;
+    cparam.split_percent = *image++;
+    cparam.merge_percent = *image++;
 
     /* Root node pointer */
-    H5F_addr_decode(udata->f, (const uint8_t **)&p, &(hdr->root.addr));
-    UINT16DECODE(p, hdr->root.node_nrec);
-    H5F_DECODE_LENGTH(udata->f, p, hdr->root.all_nrec);
+    H5F_addr_decode(udata->f, (const uint8_t **)&image, &(hdr->root.addr));
+    UINT16DECODE(image, hdr->root.node_nrec);
+    H5F_DECODE_LENGTH(udata->f, image, hdr->root.all_nrec);
 
     /* Metadata checksum */
-    UINT32DECODE(p, stored_chksum);
+    UINT32DECODE(image, stored_chksum);
 
     /* Sanity check */
-    HDassert((size_t)(p - (const uint8_t *)buf) == hdr->hdr_size);
+    HDassert((size_t)(image - (const uint8_t *)_image) == hdr->hdr_size);
 
     /* Compute checksum on entire header */
-    computed_chksum = H5_checksum_metadata(buf, (hdr->hdr_size - H5B2_SIZEOF_CHKSUM), 0);
+    computed_chksum = H5_checksum_metadata(_image, (hdr->hdr_size - H5B2_SIZEOF_CHKSUM), 0);
 
     /* Verify checksum */
     if(stored_chksum != computed_chksum)
@@ -242,131 +279,59 @@ H5B2__cache_hdr_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
         HGOTO_ERROR(H5E_BTREE, H5E_CANTINIT, NULL, "can't initialize B-tree header info")
 
     /* Set the B-tree header's address */
-    hdr->addr = addr;
+    hdr->addr = udata->addr;
+
+    /* Sanity check */
+    HDassert((size_t)(image - (const uint8_t *)_image) <= len);
 
     /* Set return value */
     ret_value = hdr;
 
 done:
-    /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-        HDONE_ERROR(H5E_BTREE, H5E_CLOSEERROR, NULL, "can't close wrapped buffer")
     if(!ret_value && hdr)
         if(H5B2__hdr_free(hdr) < 0)
             HDONE_ERROR(H5E_BTREE, H5E_CANTRELEASE, NULL, "can't release v2 B-tree header")
 
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5B2__cache_hdr_load() */ /*lint !e818 Can't make udata a pointer to const */
+} /* end H5B2__cache_hdr_deserialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5B2__cache_hdr_flush
+ * Function:    H5B2__cache_hdr_image_len
  *
- * Purpose:	Flushes a dirty B-tree header to disk.
+ * Purpose:     Compute the size of the data structure on disk.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Feb 1 2005
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              May 20, 2010
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5B2__cache_hdr_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr,
-    H5B2_hdr_t *hdr, unsigned H5_ATTR_UNUSED * flags_ptr)
+H5B2__cache_hdr_image_len(const void *_thing, size_t *image_len,
+    hbool_t H5_ATTR_UNUSED *compressed_ptr, size_t H5_ATTR_UNUSED *compressed_image_len_ptr)
 {
-    H5WB_t      *wb = NULL;             /* Wrapped buffer for header data */
-    uint8_t     hdr_buf[H5B2_HDR_BUF_SIZE]; /* Buffer for header */
-    herr_t      ret_value = SUCCEED;    /* Return value */
+    const H5B2_hdr_t *hdr = (const H5B2_hdr_t *)_thing;      /* Pointer to the B-tree header */
 
-    FUNC_ENTER_STATIC
+    FUNC_ENTER_STATIC_NOERR
 
     /* Check arguments */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
     HDassert(hdr);
+    HDassert(image_len);
 
-    if(hdr->cache_info.is_dirty) {
-        uint8_t	*buf;           /* Pointer to header buffer */
-        uint8_t *p;             /* Pointer into raw data buffer */
-        uint32_t metadata_chksum; /* Computed metadata checksum value */
-
-        /* Set the B-tree header's file context for this operation */
-        hdr->f = f;
-
-        /* Wrap the local buffer for serialized header info */
-        if(NULL == (wb = H5WB_wrap(hdr_buf, sizeof(hdr_buf))))
-            HGOTO_ERROR(H5E_BTREE, H5E_CANTINIT, FAIL, "can't wrap buffer")
-
-        /* Get a pointer to a buffer that's large enough for header */
-        if(NULL == (buf = (uint8_t *)H5WB_actual(wb, hdr->hdr_size)))
-            HGOTO_ERROR(H5E_BTREE, H5E_NOSPACE, FAIL, "can't get actual buffer")
-
-        /* Get temporary pointer to serialized header */
-        p = buf;
-
-        /* Magic number */
-        HDmemcpy(p, H5B2_HDR_MAGIC, (size_t)H5_SIZEOF_MAGIC);
-        p += H5_SIZEOF_MAGIC;
-
-        /* Version # */
-        *p++ = H5B2_HDR_VERSION;
-
-        /* B-tree type */
-        *p++ = hdr->cls->id;
+    /* Set the image length size */
+    *image_len = hdr->hdr_size;
 
-        /* Node size (in bytes) */
-        UINT32ENCODE(p, hdr->node_size);
-
-        /* Raw key size (in bytes) */
-        UINT16ENCODE(p, hdr->rrec_size);
-
-        /* Depth of tree */
-        UINT16ENCODE(p, hdr->depth);
-
-        /* Split & merge %s */
-        H5_CHECK_OVERFLOW(hdr->split_percent, /* From: */ unsigned, /* To: */ uint8_t);
-        *p++ = (uint8_t)hdr->split_percent;
-        H5_CHECK_OVERFLOW(hdr->merge_percent, /* From: */ unsigned, /* To: */ uint8_t);
-        *p++ = (uint8_t)hdr->merge_percent;
-
-        /* Root node pointer */
-        H5F_addr_encode(f, &p, hdr->root.addr);
-        UINT16ENCODE(p, hdr->root.node_nrec);
-        H5F_ENCODE_LENGTH(f, p, hdr->root.all_nrec);
-
-        /* Compute metadata checksum */
-        metadata_chksum = H5_checksum_metadata(buf, (hdr->hdr_size - H5B2_SIZEOF_CHKSUM), 0);
-
-        /* Metadata checksum */
-        UINT32ENCODE(p, metadata_chksum);
-
-        /* Write the B-tree header. */
-        HDassert((size_t)(p - buf) == hdr->hdr_size);
-        if(H5F_block_write(f, H5FD_MEM_BTREE, addr, hdr->hdr_size, dxpl_id, buf) < 0)
-            HGOTO_ERROR(H5E_BTREE, H5E_CANTFLUSH, FAIL, "unable to save B-tree header to disk")
-
-        hdr->cache_info.is_dirty = FALSE;
-    } /* end if */
-
-    if(destroy)
-        if(H5B2__cache_hdr_dest(f, hdr) < 0)
-            HGOTO_ERROR(H5E_BTREE, H5E_CANTFREE, FAIL, "unable to destroy B-tree header")
-
-done:
-    /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-        HDONE_ERROR(H5E_BTREE, H5E_CLOSEERROR, FAIL, "can't close wrapped buffer")
-
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* H5B2__cache_hdr_flush() */
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5B2__cache_hdr_image_len() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5B2__cache_hdr_dest
+ * Function:	H5B2__cache_hdr_serialize
  *
- * Purpose:	Destroys a B-tree header in memory.
+ * Purpose:	Flushes a dirty B-tree header to disk.
  *
  * Return:	Non-negative on success/Negative on failure
  *
@@ -377,109 +342,132 @@ done:
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5B2__cache_hdr_dest(H5F_t *f, H5B2_hdr_t *hdr)
+H5B2__cache_hdr_serialize(const H5F_t *f, void *_image, size_t H5_ATTR_UNUSED len,
+    void *_thing)
 {
-    herr_t ret_value = SUCCEED;     /* Return value */
+    H5B2_hdr_t *hdr = (H5B2_hdr_t *)_thing;     /* Pointer to the B-tree header */
+    uint8_t *image = (uint8_t *)_image;         /* Pointer into raw data buffer */
+    uint32_t metadata_chksum;                   /* Computed metadata checksum value */
 
-    FUNC_ENTER_STATIC
+    FUNC_ENTER_STATIC_NOERR
 
-    /* Check arguments */
+    /* check arguments */
+    HDassert(f);
+    HDassert(image);
     HDassert(hdr);
-    HDassert(hdr->rc == 0);
 
-    /* If we're going to free the space on disk, the address must be valid */
-    HDassert(!hdr->cache_info.free_file_space_on_destroy || H5F_addr_defined(hdr->cache_info.addr));
+    /* Magic number */
+    HDmemcpy(image, H5B2_HDR_MAGIC, (size_t)H5_SIZEOF_MAGIC);
+    image += H5_SIZEOF_MAGIC;
+
+    /* Version # */
+    *image++ = H5B2_HDR_VERSION;
 
-    /* Check for freeing file space for B-tree header */
-    if(hdr->cache_info.free_file_space_on_destroy) {
-        /* Release the space on disk */
-        /* (XXX: Nasty usage of internal DXPL value! -QAK) */
-        if(H5MF_xfree(f, H5FD_MEM_BTREE, H5AC_dxpl_id, hdr->cache_info.addr, (hsize_t)hdr->hdr_size) < 0)
-            HGOTO_ERROR(H5E_BTREE, H5E_CANTFREE, FAIL, "unable to free v2 B-tree header")
-    } /* end if */
+    /* B-tree type */
+    *image++ = hdr->cls->id;
 
-    /* Release B-tree header info */
-    if(H5B2__hdr_free(hdr) < 0)
-        HGOTO_ERROR(H5E_BTREE, H5E_CANTFREE, FAIL, "unable to free v2 B-tree header info")
+    /* Node size (in bytes) */
+    UINT32ENCODE(image, hdr->node_size);
 
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5B2__cache_hdr_dest() */
+    /* Raw key size (in bytes) */
+    UINT16ENCODE(image, hdr->rrec_size);
+
+    /* Depth of tree */
+    UINT16ENCODE(image, hdr->depth);
+
+    /* Split & merge %s */
+    H5_CHECK_OVERFLOW(hdr->split_percent, /* From: */ unsigned, /* To: */ uint8_t);
+    *image++ = (uint8_t)hdr->split_percent;
+    H5_CHECK_OVERFLOW(hdr->merge_percent, /* From: */ unsigned, /* To: */ uint8_t);
+    *image++ = (uint8_t)hdr->merge_percent;
+
+    /* Root node pointer */
+    H5F_addr_encode(f, &image, hdr->root.addr);
+    UINT16ENCODE(image, hdr->root.node_nrec);
+    H5F_ENCODE_LENGTH(f, image, hdr->root.all_nrec);
+
+    /* Compute metadata checksum */
+    metadata_chksum = H5_checksum_metadata(_image, (hdr->hdr_size - H5B2_SIZEOF_CHKSUM), 0);
+
+    /* Metadata checksum */
+    UINT32ENCODE(image, metadata_chksum);
+
+    /* Sanity check */
+    HDassert((size_t)(image - (uint8_t *)_image) == len);
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* H5B2__cache_hdr_serialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5B2__cache_hdr_clear
+ * Function:	H5B2__cache_hdr_free_icr
  *
- * Purpose:	Mark a B-tree header in memory as non-dirty.
+ * Purpose:	Destroy/release an "in core representation" of a data
+ *              structure
  *
  * Return:	Non-negative on success/Negative on failure
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Feb  1 2005
+ * Programmer:	Mike McGreevy
+ *              mcgreevy@hdfgroup.org
+ *              June 18, 2008
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5B2__cache_hdr_clear(H5F_t *f, H5B2_hdr_t *hdr, hbool_t destroy)
+H5B2__cache_hdr_free_icr(void *thing)
 {
-    herr_t ret_value = SUCCEED;         /* Return value */
+    herr_t ret_value = SUCCEED;     /* Return value */
 
     FUNC_ENTER_STATIC
 
-    /*
-     * Check arguments.
-     */
-    HDassert(hdr);
-
-    /* Reset the dirty flag.  */
-    hdr->cache_info.is_dirty = FALSE;
+    /* Check arguments */
+    HDassert(thing);
 
-    if(destroy)
-        if(H5B2__cache_hdr_dest(f, hdr) < 0)
-	    HGOTO_ERROR(H5E_BTREE, H5E_CANTFREE, FAIL, "unable to destroy B-tree header")
+    /* Destroy v2 B-tree header */
+    if(H5B2__hdr_free((H5B2_hdr_t *)thing) < 0)
+        HGOTO_ERROR(H5E_BTREE, H5E_CANTFREE, FAIL, "unable to free v2 B-tree header")
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5B2__cache_hdr_clear() */
+} /* H5B2__cache_hdr_free_icr() */
 
 
 /*-------------------------------------------------------------------------
- * Function:    H5B2__cache_hdr_size
+ * Function:    H5B2__cache_int_get_load_size
  *
- * Purpose:     Compute the size in bytes of a B-tree header
- *              on disk, and return it in *size_ptr.  On failure,
- *              the value of *size_ptr is undefined.
+ * Purpose:     Compute the size of the data structure on disk.
  *
- * Return:      SUCCEED (Can't fail)
+ * Return:      Non-negative on success/Negative on failure
  *
  * Programmer:  Quincey Koziol
  *              koziol@hdfgroup.org
- *              Feb 1 2005
+ *              May 18, 2010
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5B2__cache_hdr_size(const H5F_t H5_ATTR_UNUSED *f, const H5B2_hdr_t *hdr, size_t *size_ptr)
+H5B2__cache_int_get_load_size(const void *_udata, size_t *image_len)
 {
+    const H5B2_internal_cache_ud_t *udata = (const H5B2_internal_cache_ud_t *)_udata; /* User data for callback */
+
     FUNC_ENTER_STATIC_NOERR
 
     /* Check arguments */
-    HDassert(f);
-    HDassert(hdr);
-    HDassert(size_ptr);
+    HDassert(udata);
+    HDassert(udata->hdr);
+    HDassert(image_len);
 
-    /* Set size value */
-    *size_ptr = hdr->hdr_size;
+    /* Set the image length size */
+    *image_len = udata->hdr->node_size;
 
     FUNC_LEAVE_NOAPI(SUCCEED)
-} /* H5B2__cache_hdr_size() */
+} /* end H5B2__cache_int_get_load_size() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5B2__cache_internal_load
+ * Function:	H5B2__cache_int_deserialize
  *
- * Purpose:	Loads a B-tree internal node from the disk.
+ * Purpose:	Deserialize a B-tree internal node from the disk.
  *
  * Return:	Success:	Pointer to a new B-tree internal node.
  *              Failure:        NULL
@@ -490,12 +478,13 @@ H5B2__cache_hdr_size(const H5F_t H5_ATTR_UNUSED *f, const H5B2_hdr_t *hdr, size_
  *
  *-------------------------------------------------------------------------
  */
-static H5B2_internal_t *
-H5B2__cache_internal_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
+static void *
+H5B2__cache_int_deserialize(const void *_image, size_t H5_ATTR_UNUSED len,
+    void *_udata, hbool_t H5_ATTR_UNUSED *dirty)
 {
     H5B2_internal_cache_ud_t *udata = (H5B2_internal_cache_ud_t *)_udata;     /* Pointer to user data */
     H5B2_internal_t	*internal = NULL;       /* Internal node read */
-    const uint8_t	*p;             /* Pointer into raw data buffer */
+    const uint8_t	*image = (const uint8_t *)_image;       /* Pointer into raw data buffer */
     uint8_t		*native;        /* Pointer to native record info */
     H5B2_node_ptr_t	*int_node_ptr;  /* Pointer to node pointer info */
     uint32_t            stored_chksum;  /* Stored metadata checksum value */
@@ -506,8 +495,7 @@ H5B2__cache_internal_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
     FUNC_ENTER_STATIC
 
     /* Check arguments */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
+    HDassert(image);
     HDassert(udata);
 
     /* Allocate new internal node and reset cache info */
@@ -515,9 +503,6 @@ H5B2__cache_internal_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
 	HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed")
     HDmemset(&internal->cache_info, 0, sizeof(H5AC_info_t));
 
-    /* Set the B-tree header's file context for this operation */
-    udata->hdr->f = f;
-
     /* Increment ref. count on B-tree header */
     if(H5B2__hdr_incr(udata->hdr) < 0)
         HGOTO_ERROR(H5E_BTREE, H5E_CANTINC, NULL, "can't increment ref. count on B-tree header")
@@ -525,23 +510,17 @@ H5B2__cache_internal_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
     /* Share B-tree information */
     internal->hdr = udata->hdr;
 
-    /* Read header from disk */
-    if(H5F_block_read(f, H5FD_MEM_BTREE, addr, udata->hdr->node_size, dxpl_id, udata->hdr->page) < 0)
-        HGOTO_ERROR(H5E_BTREE, H5E_READERROR, NULL, "can't read B-tree internal node")
-
-    p = udata->hdr->page;
-
     /* Magic number */
-    if(HDmemcmp(p, H5B2_INT_MAGIC, (size_t)H5_SIZEOF_MAGIC))
+    if(HDmemcmp(image, H5B2_INT_MAGIC, (size_t)H5_SIZEOF_MAGIC))
         HGOTO_ERROR(H5E_BTREE, H5E_BADVALUE, NULL, "wrong B-tree internal node signature")
-    p += H5_SIZEOF_MAGIC;
+    image += H5_SIZEOF_MAGIC;
 
     /* Version */
-    if(*p++ != H5B2_INT_VERSION)
+    if(*image++ != H5B2_INT_VERSION)
 	HGOTO_ERROR(H5E_BTREE, H5E_BADRANGE, NULL, "wrong B-tree internal node version")
 
     /* B-tree type */
-    if(*p++ != (uint8_t)udata->hdr->cls->id)
+    if(*image++ != (uint8_t)udata->hdr->cls->id)
         HGOTO_ERROR(H5E_BTREE, H5E_BADTYPE, NULL, "incorrect B-tree type")
 
     /* Allocate space for the native keys in memory */
@@ -560,11 +539,11 @@ H5B2__cache_internal_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
     native = internal->int_native;
     for(u = 0; u < internal->nrec; u++) {
         /* Decode record */
-        if((udata->hdr->cls->decode)(p, native, udata->hdr->cb_ctx) < 0)
+        if((udata->hdr->cls->decode)(image, native, udata->hdr->cb_ctx) < 0)
             HGOTO_ERROR(H5E_BTREE, H5E_CANTDECODE, NULL, "unable to decode B-tree record")
 
         /* Move to next record */
-        p += udata->hdr->rrec_size;
+        image += udata->hdr->rrec_size;
         native += udata->hdr->cls->nrec_size;
     } /* end for */
 
@@ -572,10 +551,10 @@ H5B2__cache_internal_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
     int_node_ptr = internal->node_ptrs;
     for(u = 0; u < (unsigned)(internal->nrec + 1); u++) {
         /* Decode node pointer */
-        H5F_addr_decode(udata->f, (const uint8_t **)&p, &(int_node_ptr->addr));
-        UINT64DECODE_VAR(p, int_node_ptr->node_nrec, udata->hdr->max_nrec_size);
+        H5F_addr_decode(udata->f, (const uint8_t **)&image, &(int_node_ptr->addr));
+        UINT64DECODE_VAR(image, int_node_ptr->node_nrec, udata->hdr->max_nrec_size);
         if(udata->depth > 1)
-            UINT64DECODE_VAR(p, int_node_ptr->all_nrec, udata->hdr->node_info[udata->depth - 1].cum_max_nrec_size)
+            UINT64DECODE_VAR(image, int_node_ptr->all_nrec, udata->hdr->node_info[udata->depth - 1].cum_max_nrec_size)
         else
             int_node_ptr->all_nrec = int_node_ptr->node_nrec;
 
@@ -584,13 +563,13 @@ H5B2__cache_internal_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
     } /* end for */
 
     /* Compute checksum on internal node */
-    computed_chksum = H5_checksum_metadata(udata->hdr->page, (size_t)(p - (const uint8_t *)udata->hdr->page), 0);
+    computed_chksum = H5_checksum_metadata(_image, (size_t)(image - (const uint8_t *)_image), 0);
 
     /* Metadata checksum */
-    UINT32DECODE(p, stored_chksum);
+    UINT32DECODE(image, stored_chksum);
 
     /* Sanity check parsing */
-    HDassert((size_t)(p - (const uint8_t *)udata->hdr->page) <= udata->hdr->node_size);
+    HDassert((size_t)(image - (const uint8_t *)_image) <= len);
 
     /* Verify checksum */
     if(stored_chksum != computed_chksum)
@@ -605,224 +584,199 @@ done:
             HDONE_ERROR(H5E_BTREE, H5E_CANTFREE, NULL, "unable to destroy B-tree internal node")
 
     FUNC_LEAVE_NOAPI(ret_value)
-} /* H5B2__cache_internal_load() */ /*lint !e818 Can't make udata a pointer to const */
+} /* H5B2__cache_int_deserialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5B2__cache_internal_flush
+ * Function:    H5B2__cache_int_image_len
  *
- * Purpose:	Flushes a dirty B-tree internal node to disk.
+ * Purpose:     Compute the size of the data structure on disk.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Feb 3 2005
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              May 20, 2010
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5B2__cache_internal_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5B2_internal_t *internal, unsigned H5_ATTR_UNUSED * flags_ptr)
+H5B2__cache_int_image_len(const void *_thing, size_t *image_len,
+    hbool_t H5_ATTR_UNUSED *compressed_ptr, size_t H5_ATTR_UNUSED *compressed_image_len_ptr)
 {
-    herr_t      ret_value = SUCCEED;    /* Return value */
+    const H5B2_internal_t *internal = (const H5B2_internal_t *)_thing;      /* Pointer to the B-tree internal node */
 
-    FUNC_ENTER_STATIC
+    FUNC_ENTER_STATIC_NOERR
 
     /* Check arguments */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
     HDassert(internal);
     HDassert(internal->hdr);
+    HDassert(image_len);
 
-    if(internal->cache_info.is_dirty) {
-        uint8_t *p;             /* Pointer into raw data buffer */
-        uint8_t *native;        /* Pointer to native record info */
-        H5B2_node_ptr_t *int_node_ptr;      /* Pointer to node pointer info */
-        uint32_t metadata_chksum; /* Computed metadata checksum value */
-        unsigned u;             /* Local index variable */
-
-        /* Set the B-tree header's file context for this operation */
-        internal->hdr->f = f;
-
-        p = internal->hdr->page;
-
-        /* Magic number */
-        HDmemcpy(p, H5B2_INT_MAGIC, (size_t)H5_SIZEOF_MAGIC);
-        p += H5_SIZEOF_MAGIC;
-
-        /* Version # */
-        *p++ = H5B2_INT_VERSION;
-
-        /* B-tree type */
-        *p++ = internal->hdr->cls->id;
-        HDassert((size_t)(p - internal->hdr->page) == (H5B2_INT_PREFIX_SIZE - H5B2_SIZEOF_CHKSUM));
-
-        /* Serialize records for internal node */
-        native = internal->int_native;
-        for(u = 0; u < internal->nrec; u++) {
-            /* Encode record */
-            if((internal->hdr->cls->encode)(p, native, internal->hdr->cb_ctx) < 0)
-                HGOTO_ERROR(H5E_BTREE, H5E_CANTENCODE, FAIL, "unable to encode B-tree record")
-
-            /* Move to next record */
-            p += internal->hdr->rrec_size;
-            native += internal->hdr->cls->nrec_size;
-        } /* end for */
-
-        /* Serialize node pointers for internal node */
-        int_node_ptr = internal->node_ptrs;
-        for(u = 0; u < (unsigned)(internal->nrec + 1); u++) {
-            /* Encode node pointer */
-            H5F_addr_encode(f, &p, int_node_ptr->addr);
-            UINT64ENCODE_VAR(p, int_node_ptr->node_nrec, internal->hdr->max_nrec_size);
-            if(internal->depth > 1)
-                UINT64ENCODE_VAR(p, int_node_ptr->all_nrec, internal->hdr->node_info[internal->depth - 1].cum_max_nrec_size);
-
-            /* Move to next node pointer */
-            int_node_ptr++;
-        } /* end for */
-
-        /* Compute metadata checksum */
-        metadata_chksum = H5_checksum_metadata(internal->hdr->page, (size_t)(p - internal->hdr->page), 0);
-
-        /* Metadata checksum */
-        UINT32ENCODE(p, metadata_chksum);
-
-	/* Write the B-tree internal node */
-        HDassert((size_t)(p - internal->hdr->page) <= internal->hdr->node_size);
-	if(H5F_block_write(f, H5FD_MEM_BTREE, addr, internal->hdr->node_size, dxpl_id, internal->hdr->page) < 0)
-	    HGOTO_ERROR(H5E_BTREE, H5E_CANTFLUSH, FAIL, "unable to save B-tree internal node to disk")
+    /* Set the image length size */
+    *image_len = internal->hdr->node_size;
 
-	internal->cache_info.is_dirty = FALSE;
-    } /* end if */
-
-    if(destroy)
-        if(H5B2__cache_internal_dest(f, internal) < 0)
-	    HGOTO_ERROR(H5E_BTREE, H5E_CANTFREE, FAIL, "unable to destroy B-tree internal node")
-
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* H5B2__cache_internal_flush() */
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5B2__cache_int_image_len() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5B2__cache_internal_dest
+ * Function:	H5B2__cache_int_serialize
  *
- * Purpose:	Destroys a B-tree internal node in memory.
+ * Purpose:	Serializes a B-tree internal node for writing to disk.
  *
  * Return:	Non-negative on success/Negative on failure
  *
  * Programmer:	Quincey Koziol
  *		koziol@ncsa.uiuc.edu
- *		Feb 2 2005
+ *		Feb 3 2005
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5B2__cache_internal_dest(H5F_t *f, H5B2_internal_t *internal)
+H5B2__cache_int_serialize(const H5F_t *f, void *_image, size_t H5_ATTR_UNUSED len,
+    void *_thing)
 {
-    herr_t ret_value = SUCCEED;     /* Return value */
+    H5B2_internal_t *internal = (H5B2_internal_t *)_thing;      /* Pointer to the B-tree internal node */
+    uint8_t *image = (uint8_t *)_image; /* Pointer into raw data buffer */
+    uint8_t *native;        /* Pointer to native record info */
+    H5B2_node_ptr_t *int_node_ptr;      /* Pointer to node pointer info */
+    uint32_t metadata_chksum; /* Computed metadata checksum value */
+    unsigned u;             /* Local index variable */
+    herr_t      ret_value = SUCCEED;    /* Return value */
 
     FUNC_ENTER_STATIC
 
-    /* Check arguments */
+    /* check arguments */
     HDassert(f);
+    HDassert(image);
     HDassert(internal);
     HDassert(internal->hdr);
 
-    /* If we're going to free the space on disk, the address must be valid */
-    HDassert(!internal->cache_info.free_file_space_on_destroy || H5F_addr_defined(internal->cache_info.addr));
+    /* Magic number */
+    HDmemcpy(image, H5B2_INT_MAGIC, (size_t)H5_SIZEOF_MAGIC);
+    image += H5_SIZEOF_MAGIC;
+
+    /* Version # */
+    *image++ = H5B2_INT_VERSION;
 
-    /* Check for freeing file space for B-tree internal node */
-    if(internal->cache_info.free_file_space_on_destroy) {
-        /* Release the space on disk */
-        /* (XXX: Nasty usage of internal DXPL value! -QAK) */
-        if(H5MF_xfree(f, H5FD_MEM_BTREE, H5AC_dxpl_id, internal->cache_info.addr, (hsize_t)internal->hdr->node_size) < 0)
-            HGOTO_ERROR(H5E_BTREE, H5E_CANTFREE, FAIL, "unable to free v2 B-tree internal node")
-    } /* end if */
+    /* B-tree type */
+    *image++ = internal->hdr->cls->id;
+    HDassert((size_t)(image - (uint8_t *)_image) == (H5B2_INT_PREFIX_SIZE - H5B2_SIZEOF_CHKSUM));
 
-    /* Release v2 b-tree internal node */
-    if(H5B2__internal_free(internal) < 0)
-        HGOTO_ERROR(H5E_BTREE, H5E_CANTFREE, FAIL, "unable to release v2 B-tree internal node")
+    /* Serialize records for internal node */
+    native = internal->int_native;
+    for(u = 0; u < internal->nrec; u++) {
+        /* Encode record */
+        if((internal->hdr->cls->encode)(image, native, internal->hdr->cb_ctx) < 0)
+            HGOTO_ERROR(H5E_BTREE, H5E_CANTENCODE, FAIL, "unable to encode B-tree record")
+
+        /* Move to next record */
+        image += internal->hdr->rrec_size;
+        native += internal->hdr->cls->nrec_size;
+    } /* end for */
+
+    /* Serialize node pointers for internal node */
+    int_node_ptr = internal->node_ptrs;
+    for(u = 0; u < (unsigned)(internal->nrec + 1); u++) {
+        /* Encode node pointer */
+        H5F_addr_encode(f, &image, int_node_ptr->addr);
+        UINT64ENCODE_VAR(image, int_node_ptr->node_nrec, internal->hdr->max_nrec_size);
+        if(internal->depth > 1)
+            UINT64ENCODE_VAR(image, int_node_ptr->all_nrec, internal->hdr->node_info[internal->depth - 1].cum_max_nrec_size);
+
+        /* Move to next node pointer */
+        int_node_ptr++;
+    } /* end for */
+
+    /* Compute metadata checksum */
+    metadata_chksum = H5_checksum_metadata(_image, (size_t)(image - (uint8_t *)_image), 0);
+
+    /* Metadata checksum */
+    UINT32ENCODE(image, metadata_chksum);
+
+    /* Sanity check */
+    HDassert((size_t)(image - (uint8_t *)_image) <= len);
+
+#ifdef H5_CLEAR_MEMORY
+    /* Clear rest of internal node */
+    HDmemset(image, 0, len - (size_t)(image - (uint8_t *)_image));
+#endif /* H5_CLEAR_MEMORY */
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5B2__cache_internal_dest() */
+} /* H5B2__cache_int_serialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5B2__cache_internal_clear
+ * Function:	H5B2__cache_int_free_icr
  *
- * Purpose:	Mark a B-tree internal node in memory as non-dirty.
+ * Purpose:	Destroy/release an "in core representation" of a data
+ *              structure
  *
  * Return:	Non-negative on success/Negative on failure
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Feb  2 2005
+ * Programmer:	Mike McGreevy
+ *              mcgreevy@hdfgroup.org
+ *              June 18, 2008
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5B2__cache_internal_clear(H5F_t *f, H5B2_internal_t *internal, hbool_t destroy)
+H5B2__cache_int_free_icr(void *thing)
 {
-    herr_t ret_value = SUCCEED;
+    herr_t ret_value = SUCCEED;     /* Return value */
 
     FUNC_ENTER_STATIC
 
-    /*
-     * Check arguments.
-     */
-    HDassert(internal);
-
-    /* Reset the dirty flag.  */
-    internal->cache_info.is_dirty = FALSE;
+    /* Check arguments */
+    HDassert(thing);
 
-    if(destroy)
-        if(H5B2__cache_internal_dest(f, internal) < 0)
-	    HGOTO_ERROR(H5E_BTREE, H5E_CANTFREE, FAIL, "unable to destroy B-tree internal node")
+    /* Release v2 B-tree internal node */
+    if(H5B2__internal_free((H5B2_internal_t *)thing) < 0)
+        HGOTO_ERROR(H5E_BTREE, H5E_CANTFREE, FAIL, "unable to release v2 B-tree internal node")
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5B2__cache_internal_clear() */
+} /* H5B2__cache_int_free_icr() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5B2__cache_internal_size
+ * Function:    H5B2__cache_leaf_get_load_size
  *
- * Purpose:	Compute the size in bytes of a B-tree internal node
- *		on disk, and return it in *size_ptr.  On failure,
- *		the value of *size_ptr is undefined.
+ * Purpose:     Compute the size of the data structure on disk.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Feb 2 2005
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              May 18, 2010
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5B2__cache_internal_size(const H5F_t H5_ATTR_UNUSED *f, const H5B2_internal_t *internal, size_t *size_ptr)
+H5B2__cache_leaf_get_load_size(const void *_udata, size_t *image_len)
 {
+    const H5B2_leaf_cache_ud_t *udata = (const H5B2_leaf_cache_ud_t *)_udata; /* User data for callback */
+
     FUNC_ENTER_STATIC_NOERR
 
     /* Check arguments */
-    HDassert(internal);
-    HDassert(internal->hdr);
-    HDassert(size_ptr);
+    HDassert(udata);
+    HDassert(udata->hdr);
+    HDassert(image_len);
 
-    /* Set size value */
-    *size_ptr = internal->hdr->node_size;
+    /* Set the image length size */
+    *image_len = udata->hdr->node_size;
 
     FUNC_LEAVE_NOAPI(SUCCEED)
-} /* H5B2__cache_internal_size() */
+} /* end H5B2__cache_leaf_get_load_size() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5B2__cache_leaf_load
+ * Function:	H5B2__cache_leaf_deserialize
  *
- * Purpose:	Loads a B-tree leaf from the disk.
+ * Purpose:	Deserialize a B-tree leaf from the disk.
  *
  * Return:	Success:	Pointer to a new B-tree leaf node.
  *		Failure:	NULL
@@ -833,12 +787,13 @@ H5B2__cache_internal_size(const H5F_t H5_ATTR_UNUSED *f, const H5B2_internal_t *
  *
  *-------------------------------------------------------------------------
  */
-static H5B2_leaf_t *
-H5B2__cache_leaf_load(H5F_t H5_ATTR_UNUSED *f, hid_t dxpl_id, haddr_t addr, void *_udata)
+static void *
+H5B2__cache_leaf_deserialize(const void *_image, size_t H5_ATTR_UNUSED len,
+    void *_udata, hbool_t H5_ATTR_UNUSED *dirty)
 {
     H5B2_leaf_cache_ud_t *udata = (H5B2_leaf_cache_ud_t *)_udata;
     H5B2_leaf_t		*leaf = NULL;   /* Pointer to lead node loaded */
-    const uint8_t	*p;             /* Pointer into raw data buffer */
+    const uint8_t	*image = (const uint8_t *)_image;       /* Pointer into raw data buffer */
     uint8_t		*native;        /* Pointer to native keys */
     uint32_t            stored_chksum;  /* Stored metadata checksum value */
     uint32_t            computed_chksum; /* Computed metadata checksum value */
@@ -848,8 +803,7 @@ H5B2__cache_leaf_load(H5F_t H5_ATTR_UNUSED *f, hid_t dxpl_id, haddr_t addr, void
     FUNC_ENTER_STATIC
 
     /* Check arguments */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
+    HDassert(image);
     HDassert(udata);
 
     /* Allocate new leaf node and reset cache info */
@@ -857,9 +811,6 @@ H5B2__cache_leaf_load(H5F_t H5_ATTR_UNUSED *f, hid_t dxpl_id, haddr_t addr, void
 	HGOTO_ERROR(H5E_BTREE, H5E_CANTALLOC, NULL, "memory allocation failed")
     HDmemset(&leaf->cache_info, 0, sizeof(H5AC_info_t));
 
-    /* Set the B-tree header's file context for this operation */
-    udata->hdr->f = udata->f;
-
     /* Increment ref. count on B-tree header */
     if(H5B2__hdr_incr(udata->hdr) < 0)
         HGOTO_ERROR(H5E_BTREE, H5E_CANTINC, NULL, "can't increment ref. count on B-tree header")
@@ -867,23 +818,17 @@ H5B2__cache_leaf_load(H5F_t H5_ATTR_UNUSED *f, hid_t dxpl_id, haddr_t addr, void
     /* Share B-tree header information */
     leaf->hdr = udata->hdr;
 
-    /* Read header from disk */
-    if(H5F_block_read(udata->f, H5FD_MEM_BTREE, addr, udata->hdr->node_size, dxpl_id, udata->hdr->page) < 0)
-        HGOTO_ERROR(H5E_BTREE, H5E_READERROR, NULL, "can't read B-tree leaf node")
-
-    p = udata->hdr->page;
-
     /* Magic number */
-    if(HDmemcmp(p, H5B2_LEAF_MAGIC, (size_t)H5_SIZEOF_MAGIC))
+    if(HDmemcmp(image, H5B2_LEAF_MAGIC, (size_t)H5_SIZEOF_MAGIC))
 	HGOTO_ERROR(H5E_BTREE, H5E_BADVALUE, NULL, "wrong B-tree leaf node signature")
-    p += H5_SIZEOF_MAGIC;
+    image += H5_SIZEOF_MAGIC;
 
     /* Version */
-    if(*p++ != H5B2_LEAF_VERSION)
+    if(*image++ != H5B2_LEAF_VERSION)
 	HGOTO_ERROR(H5E_BTREE, H5E_BADRANGE, NULL, "wrong B-tree leaf node version")
 
     /* B-tree type */
-    if(*p++ != (uint8_t)udata->hdr->cls->id)
+    if(*image++ != (uint8_t)udata->hdr->cls->id)
         HGOTO_ERROR(H5E_BTREE, H5E_BADTYPE, NULL, "incorrect B-tree type")
 
     /* Allocate space for the native keys in memory */
@@ -897,27 +842,30 @@ H5B2__cache_leaf_load(H5F_t H5_ATTR_UNUSED *f, hid_t dxpl_id, haddr_t addr, void
     native = leaf->leaf_native;
     for(u = 0; u < leaf->nrec; u++) {
         /* Decode record */
-        if((udata->hdr->cls->decode)(p, native, udata->hdr->cb_ctx) < 0)
+        if((udata->hdr->cls->decode)(image, native, udata->hdr->cb_ctx) < 0)
             HGOTO_ERROR(H5E_BTREE, H5E_CANTENCODE, NULL, "unable to decode B-tree record")
 
         /* Move to next record */
-        p += udata->hdr->rrec_size;
+        image += udata->hdr->rrec_size;
         native += udata->hdr->cls->nrec_size;
     } /* end for */
 
     /* Compute checksum on leaf node */
-    computed_chksum = H5_checksum_metadata(udata->hdr->page, (size_t)(p - (const uint8_t *)udata->hdr->page), 0);
+    computed_chksum = H5_checksum_metadata(_image, (size_t)(image - (const uint8_t *)_image), 0);
 
     /* Metadata checksum */
-    UINT32DECODE(p, stored_chksum);
+    UINT32DECODE(image, stored_chksum);
 
     /* Sanity check parsing */
-    HDassert((size_t)(p - (const uint8_t *)udata->hdr->page) <= udata->hdr->node_size);
+    HDassert((size_t)(image - (const uint8_t *)_image) <= udata->hdr->node_size);
 
     /* Verify checksum */
     if(stored_chksum != computed_chksum)
 	HGOTO_ERROR(H5E_BTREE, H5E_BADVALUE, NULL, "incorrect metadata checksum for v2 leaf node")
 
+    /* Sanity check */
+    HDassert((size_t)(image - (const uint8_t *)_image) <= len);
+
     /* Set return value */
     ret_value = leaf;
 
@@ -927,96 +875,46 @@ done:
             HDONE_ERROR(H5E_BTREE, H5E_CANTFREE, NULL, "unable to destroy B-tree leaf node")
 
     FUNC_LEAVE_NOAPI(ret_value)
-} /* H5B2__cache_leaf_load() */ /*lint !e818 Can't make udata a pointer to const */
+} /* H5B2__cache_leaf_deserialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5B2__cache_leaf_flush
+ * Function:    H5B2__cache_leaf_image_len
  *
- * Purpose:	Flushes a dirty B-tree leaf node to disk.
+ * Purpose:     Compute the size of the data structure on disk.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Feb 2 2005
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              May 20, 2010
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5B2__cache_leaf_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5B2_leaf_t *leaf, unsigned H5_ATTR_UNUSED * flags_ptr)
+H5B2__cache_leaf_image_len(const void *_thing, size_t *image_len,
+    hbool_t H5_ATTR_UNUSED *compressed_ptr, size_t H5_ATTR_UNUSED *compressed_image_len_ptr)
 {
-    herr_t      ret_value = SUCCEED;    /* Return value */
+    const H5B2_leaf_t *leaf = (const H5B2_leaf_t *)_thing;      /* Pointer to the B-tree leaf node  */
 
-    FUNC_ENTER_STATIC
+    FUNC_ENTER_STATIC_NOERR
 
     /* Check arguments */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
     HDassert(leaf);
     HDassert(leaf->hdr);
+    HDassert(image_len);
 
-    if(leaf->cache_info.is_dirty) {
-        uint8_t *p;             /* Pointer into raw data buffer */
-        uint8_t *native;        /* Pointer to native keys */
-        uint32_t metadata_chksum; /* Computed metadata checksum value */
-        unsigned u;             /* Local index variable */
-
-        /* Set the B-tree header's file context for this operation */
-        leaf->hdr->f = f;
-
-        p = leaf->hdr->page;
-
-        /* magic number */
-        HDmemcpy(p, H5B2_LEAF_MAGIC, (size_t)H5_SIZEOF_MAGIC);
-        p += H5_SIZEOF_MAGIC;
-
-        /* version # */
-        *p++ = H5B2_LEAF_VERSION;
-
-        /* b-tree type */
-        *p++ = leaf->hdr->cls->id;
-        HDassert((size_t)(p - leaf->hdr->page) == (H5B2_LEAF_PREFIX_SIZE - H5B2_SIZEOF_CHKSUM));
-
-        /* Serialize records for leaf node */
-        native = leaf->leaf_native;
-        for(u = 0; u < leaf->nrec; u++) {
-            /* Encode record */
-            if((leaf->hdr->cls->encode)(p, native, leaf->hdr->cb_ctx) < 0)
-                HGOTO_ERROR(H5E_BTREE, H5E_CANTENCODE, FAIL, "unable to encode B-tree record")
-
-            /* Move to next record */
-            p += leaf->hdr->rrec_size;
-            native += leaf->hdr->cls->nrec_size;
-        } /* end for */
-
-        /* Compute metadata checksum */
-        metadata_chksum = H5_checksum_metadata(leaf->hdr->page, (size_t)(p - leaf->hdr->page), 0);
-
-        /* Metadata checksum */
-        UINT32ENCODE(p, metadata_chksum);
-
-	/* Write the B-tree leaf node */
-        HDassert((size_t)(p - leaf->hdr->page) <= leaf->hdr->node_size);
-	if(H5F_block_write(f, H5FD_MEM_BTREE, addr, leaf->hdr->node_size, dxpl_id, leaf->hdr->page) < 0)
-	    HGOTO_ERROR(H5E_BTREE, H5E_CANTFLUSH, FAIL, "unable to save B-tree leaf node to disk")
-
-	leaf->cache_info.is_dirty = FALSE;
-    } /* end if */
-
-    if(destroy)
-        if(H5B2__cache_leaf_dest(f, leaf) < 0)
-	    HGOTO_ERROR(H5E_BTREE, H5E_CANTFREE, FAIL, "unable to destroy B-tree leaf node")
+    /* Set the image length size */
+    *image_len = leaf->hdr->node_size;
 
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* H5B2__cache_leaf_flush() */
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5B2__cache_leaf_image_len() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5B2__cache_leaf_dest
+ * Function:	H5B2__cache_leaf_serialize
  *
- * Purpose:	Destroys a B-tree leaf node in memory.
+ * Purpose:	Serializes a B-tree leaf node for writing to disk.
  *
  * Return:	Non-negative on success/Negative on failure
  *
@@ -1027,102 +925,95 @@ done:
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5B2__cache_leaf_dest(H5F_t *f, H5B2_leaf_t *leaf)
+H5B2__cache_leaf_serialize(const H5F_t *f, void *_image, size_t H5_ATTR_UNUSED len,
+    void *_thing)
 {
-    herr_t ret_value = SUCCEED;     /* Return value */
+    H5B2_leaf_t *leaf = (H5B2_leaf_t *)_thing;      /* Pointer to the B-tree leaf node  */
+    uint8_t *image = (uint8_t *)_image;         /* Pointer into raw data buffer */
+    uint8_t *native;            /* Pointer to native keys */
+    uint32_t metadata_chksum;   /* Computed metadata checksum value */
+    unsigned u;                 /* Local index variable */
+    herr_t ret_value = SUCCEED; /* Return value */
 
     FUNC_ENTER_STATIC
 
-    /* Check arguments */
+    /* check arguments */
     HDassert(f);
+    HDassert(image);
     HDassert(leaf);
     HDassert(leaf->hdr);
 
-    /* If we're going to free the space on disk, the address must be valid */
-    HDassert(!leaf->cache_info.free_file_space_on_destroy || H5F_addr_defined(leaf->cache_info.addr));
+    /* magic number */
+    HDmemcpy(image, H5B2_LEAF_MAGIC, (size_t)H5_SIZEOF_MAGIC);
+    image += H5_SIZEOF_MAGIC;
 
-    /* Check for freeing file space for B-tree leaf node */
-    if(leaf->cache_info.free_file_space_on_destroy) {
-        /* Release the space on disk */
-        /* (XXX: Nasty usage of internal DXPL value! -QAK) */
-        if(H5MF_xfree(f, H5FD_MEM_BTREE, H5AC_dxpl_id, leaf->cache_info.addr, (hsize_t)leaf->hdr->node_size) < 0)
-            HGOTO_ERROR(H5E_BTREE, H5E_CANTFREE, FAIL, "unable to free v2 B-tree leaf node")
-    } /* end if */
+    /* version # */
+    *image++ = H5B2_LEAF_VERSION;
 
-    /* Destroy v2 b-tree leaf node */
-    if(H5B2__leaf_free(leaf) < 0)
-        HGOTO_ERROR(H5E_BTREE, H5E_CANTFREE, FAIL, "unable to destroy B-tree leaf node")
+    /* B-tree type */
+    *image++ = leaf->hdr->cls->id;
+    HDassert((size_t)(image - (uint8_t *)_image) == (H5B2_LEAF_PREFIX_SIZE - H5B2_SIZEOF_CHKSUM));
 
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5B2__cache_leaf_dest() */
+    /* Serialize records for leaf node */
+    native = leaf->leaf_native;
+    for(u = 0; u < leaf->nrec; u++) {
+        /* Encode record */
+        if((leaf->hdr->cls->encode)(image, native, leaf->hdr->cb_ctx) < 0)
+            HGOTO_ERROR(H5E_BTREE, H5E_CANTENCODE, FAIL, "unable to encode B-tree record")
 
-
-/*-------------------------------------------------------------------------
- * Function:	H5B2__cache_leaf_clear
- *
- * Purpose:	Mark a B-tree leaf node in memory as non-dirty.
- *
- * Return:	Non-negative on success/Negative on failure
- *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Feb  2 2005
- *
- *-------------------------------------------------------------------------
- */
-static herr_t
-H5B2__cache_leaf_clear(H5F_t *f, H5B2_leaf_t *leaf, hbool_t destroy)
-{
-    herr_t ret_value = SUCCEED;
+        /* Move to next record */
+        image += leaf->hdr->rrec_size;
+        native += leaf->hdr->cls->nrec_size;
+    } /* end for */
 
-    FUNC_ENTER_STATIC
+    /* Compute metadata checksum */
+    metadata_chksum = H5_checksum_metadata(_image, (size_t)((const uint8_t *)image - (const uint8_t *)_image), 0);
 
-    /*
-     * Check arguments.
-     */
-    HDassert(leaf);
+    /* Metadata checksum */
+    UINT32ENCODE(image, metadata_chksum);
 
-    /* Reset the dirty flag.  */
-    leaf->cache_info.is_dirty = FALSE;
+    /* Sanity check */
+    HDassert((size_t)(image - (uint8_t *)_image) <= len);
 
-    if(destroy)
-        if(H5B2__cache_leaf_dest(f, leaf) < 0)
-	    HGOTO_ERROR(H5E_BTREE, H5E_CANTFREE, FAIL, "unable to destroy B-tree leaf node")
+#ifdef H5_CLEAR_MEMORY
+    /* Clear rest of leaf node */
+    HDmemset(image, 0, len - (size_t)(image - (uint8_t *)_image));
+#endif /* H5_CLEAR_MEMORY */
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5B2__cache_leaf_clear() */
+} /* H5B2__cache_leaf_serialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5B2__cache_leaf_size
+ * Function:	H5B2__cache_leaf_free_icr
  *
- * Purpose:	Compute the size in bytes of a B-tree leaf node
- *		on disk, and return it in *size_ptr.  On failure,
- *		the value of *size_ptr is undefined.
+ * Purpose:	Destroy/release an "in core representation" of a data
+ *              structure
  *
  * Return:	Non-negative on success/Negative on failure
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Feb 2 2005
+ * Programmer:	Mike McGreevy
+ *              mcgreevy@hdfgroup.org
+ *              June 18, 2008
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5B2__cache_leaf_size(const H5F_t H5_ATTR_UNUSED *f, const H5B2_leaf_t *leaf, size_t *size_ptr)
+H5B2__cache_leaf_free_icr(void *thing)
 {
-    FUNC_ENTER_STATIC_NOERR
+    herr_t ret_value = SUCCEED;     /* Return value */
 
-    /* check arguments */
-    HDassert(leaf);
-    HDassert(leaf->hdr);
-    HDassert(size_ptr);
+    FUNC_ENTER_STATIC
 
-    /* Set size value */
-    *size_ptr = leaf->hdr->node_size;
+    /* Check arguments */
+    HDassert(thing);
 
-    FUNC_LEAVE_NOAPI(SUCCEED)
-} /* H5B2__cache_leaf_size() */
+    /* Destroy v2 B-tree leaf node */
+    if(H5B2__leaf_free((H5B2_leaf_t *)thing) < 0)
+        HGOTO_ERROR(H5E_BTREE, H5E_CANTFREE, FAIL, "unable to destroy B-tree leaf node")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5B2__cache_leaf_free_icr() */
 
diff --git a/src/H5B2dbg.c b/src/H5B2dbg.c
index 50283f8..6e1250b 100644
--- a/src/H5B2dbg.c
+++ b/src/H5B2dbg.c
@@ -123,8 +123,9 @@ H5B2__hdr_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE *stream, int indent,
      * Load the B-tree header.
      */
     cache_udata.f = f;
+    cache_udata.addr = addr;
     cache_udata.ctx_udata = dbg_ctx;
-    if(NULL == (hdr = (H5B2_hdr_t *)H5AC_protect(f, dxpl_id, H5AC_BT2_HDR, addr, &cache_udata, H5AC_READ)))
+    if(NULL == (hdr = (H5B2_hdr_t *)H5AC_protect(f, dxpl_id, H5AC_BT2_HDR, addr, &cache_udata, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_BTREE, H5E_CANTLOAD, FAIL, "unable to load B-tree header")
 
     /* Set file pointer for this B-tree operation */
@@ -241,8 +242,9 @@ H5B2__int_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE *stream, int indent,
      * Load the B-tree header.
      */
     cache_udata.f = f;
+    cache_udata.addr = hdr_addr;
     cache_udata.ctx_udata = dbg_ctx;
-    if(NULL == (hdr = (H5B2_hdr_t *)H5AC_protect(f, dxpl_id, H5AC_BT2_HDR, hdr_addr, &cache_udata, H5AC_READ)))
+    if(NULL == (hdr = (H5B2_hdr_t *)H5AC_protect(f, dxpl_id, H5AC_BT2_HDR, hdr_addr, &cache_udata, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_BTREE, H5E_CANTLOAD, FAIL, "unable to load B-tree header")
 
     /* Set file pointer for this B-tree operation */
@@ -253,7 +255,7 @@ H5B2__int_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE *stream, int indent,
      */
     H5_CHECK_OVERFLOW(nrec, unsigned, uint16_t);
     H5_CHECK_OVERFLOW(depth, unsigned, uint16_t);
-    if(NULL == (internal = H5B2__protect_internal(hdr, dxpl_id, addr, (uint16_t)nrec, (uint16_t)depth, H5AC_READ)))
+    if(NULL == (internal = H5B2__protect_internal(hdr, dxpl_id, addr, (uint16_t)nrec, (uint16_t)depth, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_BTREE, H5E_CANTLOAD, FAIL, "unable to load B-tree internal node")
 
     /* Print opening message */
@@ -375,8 +377,9 @@ H5B2__leaf_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE *stream, int indent
      * Load the B-tree header.
      */
     cache_udata.f = f;
+    cache_udata.addr = hdr_addr;
     cache_udata.ctx_udata = dbg_ctx;
-    if(NULL == (hdr = (H5B2_hdr_t *)H5AC_protect(f, dxpl_id, H5AC_BT2_HDR, hdr_addr, &cache_udata, H5AC_READ)))
+    if(NULL == (hdr = (H5B2_hdr_t *)H5AC_protect(f, dxpl_id, H5AC_BT2_HDR, hdr_addr, &cache_udata, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree header")
 
     /* Set file pointer for this B-tree operation */
@@ -386,7 +389,7 @@ H5B2__leaf_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE *stream, int indent
      * Load the B-tree leaf node
      */
     H5_CHECK_OVERFLOW(nrec, unsigned, uint16_t);
-    if(NULL == (leaf = H5B2__protect_leaf(hdr, dxpl_id, addr, (uint16_t)nrec, H5AC_READ)))
+    if(NULL == (leaf = H5B2__protect_leaf(hdr, dxpl_id, addr, (uint16_t)nrec, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree leaf node")
 
     /* Print opening message */
diff --git a/src/H5B2int.c b/src/H5B2int.c
index 638b4b3..0f884c2 100644
--- a/src/H5B2int.c
+++ b/src/H5B2int.c
@@ -215,9 +215,9 @@ H5B2__split1(H5B2_hdr_t *hdr, hid_t dxpl_id, uint16_t depth,
         right_addr = internal->node_ptrs[idx + 1].addr;
 
         /* Protect both leaves */
-        if(NULL == (left_int = H5B2__protect_internal(hdr, dxpl_id, left_addr, internal->node_ptrs[idx].node_nrec, (uint16_t)(depth - 1), H5AC_WRITE)))
+        if(NULL == (left_int = H5B2__protect_internal(hdr, dxpl_id, left_addr, internal->node_ptrs[idx].node_nrec, (uint16_t)(depth - 1), H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree internal node")
-        if(NULL == (right_int = H5B2__protect_internal(hdr, dxpl_id, right_addr, internal->node_ptrs[idx + 1].node_nrec, (uint16_t)(depth - 1), H5AC_WRITE)))
+        if(NULL == (right_int = H5B2__protect_internal(hdr, dxpl_id, right_addr, internal->node_ptrs[idx + 1].node_nrec, (uint16_t)(depth - 1), H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree internal node")
 
         /* More setup for child nodes */
@@ -244,9 +244,9 @@ H5B2__split1(H5B2_hdr_t *hdr, hid_t dxpl_id, uint16_t depth,
         right_addr = internal->node_ptrs[idx + 1].addr;
 
         /* Protect both leaves */
-        if(NULL == (left_leaf = H5B2__protect_leaf(hdr, dxpl_id, left_addr, internal->node_ptrs[idx].node_nrec, H5AC_WRITE)))
+        if(NULL == (left_leaf = H5B2__protect_leaf(hdr, dxpl_id, left_addr, internal->node_ptrs[idx].node_nrec, H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree leaf node")
-        if(NULL == (right_leaf = H5B2__protect_leaf(hdr, dxpl_id, right_addr, internal->node_ptrs[idx + 1].node_nrec, H5AC_WRITE)))
+        if(NULL == (right_leaf = H5B2__protect_leaf(hdr, dxpl_id, right_addr, internal->node_ptrs[idx + 1].node_nrec, H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree leaf node")
 
         /* More setup for child nodes */
@@ -403,7 +403,7 @@ H5B2__split_root(H5B2_hdr_t *hdr, hid_t dxpl_id)
         HGOTO_ERROR(H5E_BTREE, H5E_CANTINIT, FAIL, "unable to create new internal node")
 
     /* Protect new root node */
-    if(NULL == (new_root = H5B2__protect_internal(hdr, dxpl_id, hdr->root.addr, hdr->root.node_nrec, hdr->depth, H5AC_WRITE)))
+    if(NULL == (new_root = H5B2__protect_internal(hdr, dxpl_id, hdr->root.addr, hdr->root.node_nrec, hdr->depth, H5AC__NO_FLAGS_SET)))
         HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree internal node")
 
     /* Set first node pointer in root node to old root node pointer info */
@@ -467,9 +467,9 @@ H5B2__redistribute2(H5B2_hdr_t *hdr, hid_t dxpl_id, uint16_t depth,
         right_addr = internal->node_ptrs[idx + 1].addr;
 
         /* Lock left & right B-tree child nodes */
-        if(NULL == (left_internal = H5B2__protect_internal(hdr, dxpl_id, left_addr, internal->node_ptrs[idx].node_nrec, (uint16_t)(depth - 1), H5AC_WRITE)))
+        if(NULL == (left_internal = H5B2__protect_internal(hdr, dxpl_id, left_addr, internal->node_ptrs[idx].node_nrec, (uint16_t)(depth - 1), H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree leaf node")
-        if(NULL == (right_internal = H5B2__protect_internal(hdr, dxpl_id, right_addr, internal->node_ptrs[idx + 1].node_nrec, (uint16_t)(depth - 1), H5AC_WRITE)))
+        if(NULL == (right_internal = H5B2__protect_internal(hdr, dxpl_id, right_addr, internal->node_ptrs[idx + 1].node_nrec, (uint16_t)(depth - 1), H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree leaf node")
 
         /* More setup for child nodes */
@@ -492,9 +492,9 @@ H5B2__redistribute2(H5B2_hdr_t *hdr, hid_t dxpl_id, uint16_t depth,
         right_addr = internal->node_ptrs[idx + 1].addr;
 
         /* Lock left & right B-tree child nodes */
-        if(NULL == (left_leaf = H5B2__protect_leaf(hdr, dxpl_id, left_addr, internal->node_ptrs[idx].node_nrec, H5AC_WRITE)))
+        if(NULL == (left_leaf = H5B2__protect_leaf(hdr, dxpl_id, left_addr, internal->node_ptrs[idx].node_nrec, H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree leaf node")
-        if(NULL == (right_leaf = H5B2__protect_leaf(hdr, dxpl_id, right_addr, internal->node_ptrs[idx + 1].node_nrec, H5AC_WRITE)))
+        if(NULL == (right_leaf = H5B2__protect_leaf(hdr, dxpl_id, right_addr, internal->node_ptrs[idx + 1].node_nrec, H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree leaf node")
 
         /* More setup for child nodes */
@@ -704,11 +704,11 @@ H5B2__redistribute3(H5B2_hdr_t *hdr, hid_t dxpl_id, uint16_t depth,
         right_addr = internal->node_ptrs[idx + 1].addr;
 
         /* Lock B-tree child nodes */
-        if(NULL == (left_internal = H5B2__protect_internal(hdr, dxpl_id, left_addr, internal->node_ptrs[idx - 1].node_nrec, (uint16_t)(depth - 1), H5AC_WRITE)))
+        if(NULL == (left_internal = H5B2__protect_internal(hdr, dxpl_id, left_addr, internal->node_ptrs[idx - 1].node_nrec, (uint16_t)(depth - 1), H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree internal node")
-        if(NULL == (middle_internal = H5B2__protect_internal(hdr, dxpl_id, middle_addr, internal->node_ptrs[idx].node_nrec, (uint16_t)(depth - 1), H5AC_WRITE)))
+        if(NULL == (middle_internal = H5B2__protect_internal(hdr, dxpl_id, middle_addr, internal->node_ptrs[idx].node_nrec, (uint16_t)(depth - 1), H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree internal node")
-        if(NULL == (right_internal = H5B2__protect_internal(hdr, dxpl_id, right_addr, internal->node_ptrs[idx + 1].node_nrec, (uint16_t)(depth - 1), H5AC_WRITE)))
+        if(NULL == (right_internal = H5B2__protect_internal(hdr, dxpl_id, right_addr, internal->node_ptrs[idx + 1].node_nrec, (uint16_t)(depth - 1), H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree internal node")
 
         /* More setup for child nodes */
@@ -737,11 +737,11 @@ H5B2__redistribute3(H5B2_hdr_t *hdr, hid_t dxpl_id, uint16_t depth,
         right_addr = internal->node_ptrs[idx + 1].addr;
 
         /* Lock B-tree child nodes */
-        if(NULL == (left_leaf = H5B2__protect_leaf(hdr, dxpl_id, left_addr, internal->node_ptrs[idx - 1].node_nrec, H5AC_WRITE)))
+        if(NULL == (left_leaf = H5B2__protect_leaf(hdr, dxpl_id, left_addr, internal->node_ptrs[idx - 1].node_nrec, H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree leaf node")
-        if(NULL == (middle_leaf = H5B2__protect_leaf(hdr, dxpl_id, middle_addr, internal->node_ptrs[idx].node_nrec, H5AC_WRITE)))
+        if(NULL == (middle_leaf = H5B2__protect_leaf(hdr, dxpl_id, middle_addr, internal->node_ptrs[idx].node_nrec, H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree leaf node")
-        if(NULL == (right_leaf = H5B2__protect_leaf(hdr, dxpl_id, right_addr, internal->node_ptrs[idx + 1].node_nrec, H5AC_WRITE)))
+        if(NULL == (right_leaf = H5B2__protect_leaf(hdr, dxpl_id, right_addr, internal->node_ptrs[idx + 1].node_nrec, H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree leaf node")
 
         /* More setup for child nodes */
@@ -1084,9 +1084,9 @@ H5B2__merge2(H5B2_hdr_t *hdr, hid_t dxpl_id, uint16_t depth,
         right_addr = internal->node_ptrs[idx + 1].addr;
 
         /* Lock left & right B-tree child nodes */
-        if(NULL == (left_internal = H5B2__protect_internal(hdr, dxpl_id, left_addr, internal->node_ptrs[idx].node_nrec, (uint16_t)(depth - 1), H5AC_WRITE)))
+        if(NULL == (left_internal = H5B2__protect_internal(hdr, dxpl_id, left_addr, internal->node_ptrs[idx].node_nrec, (uint16_t)(depth - 1), H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree internal node")
-        if(NULL == (right_internal = H5B2__protect_internal(hdr, dxpl_id, right_addr, internal->node_ptrs[idx + 1].node_nrec, (uint16_t)(depth - 1), H5AC_WRITE)))
+        if(NULL == (right_internal = H5B2__protect_internal(hdr, dxpl_id, right_addr, internal->node_ptrs[idx + 1].node_nrec, (uint16_t)(depth - 1), H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree internal node")
 
         /* More setup for accessing child node information */
@@ -1109,9 +1109,9 @@ H5B2__merge2(H5B2_hdr_t *hdr, hid_t dxpl_id, uint16_t depth,
         right_addr = internal->node_ptrs[idx + 1].addr;
 
         /* Lock left & right B-tree child nodes */
-        if(NULL == (left_leaf = H5B2__protect_leaf(hdr, dxpl_id, left_addr, internal->node_ptrs[idx].node_nrec, H5AC_WRITE)))
+        if(NULL == (left_leaf = H5B2__protect_leaf(hdr, dxpl_id, left_addr, internal->node_ptrs[idx].node_nrec, H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree leaf node")
-        if(NULL == (right_leaf = H5B2__protect_leaf(hdr, dxpl_id, right_addr, internal->node_ptrs[idx + 1].node_nrec, H5AC_WRITE)))
+        if(NULL == (right_leaf = H5B2__protect_leaf(hdr, dxpl_id, right_addr, internal->node_ptrs[idx + 1].node_nrec, H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree leaf node")
 
         /* More setup for accessing child node information */
@@ -1246,11 +1246,11 @@ H5B2__merge3(H5B2_hdr_t *hdr, hid_t dxpl_id, uint16_t depth,
         right_addr = internal->node_ptrs[idx + 1].addr;
 
         /* Lock B-tree child nodes */
-        if(NULL == (left_internal = H5B2__protect_internal(hdr, dxpl_id, left_addr, internal->node_ptrs[idx - 1].node_nrec, (uint16_t)(depth - 1), H5AC_WRITE)))
+        if(NULL == (left_internal = H5B2__protect_internal(hdr, dxpl_id, left_addr, internal->node_ptrs[idx - 1].node_nrec, (uint16_t)(depth - 1), H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree internal node")
-        if(NULL == (middle_internal = H5B2__protect_internal(hdr, dxpl_id, middle_addr, internal->node_ptrs[idx].node_nrec, (uint16_t)(depth - 1), H5AC_WRITE)))
+        if(NULL == (middle_internal = H5B2__protect_internal(hdr, dxpl_id, middle_addr, internal->node_ptrs[idx].node_nrec, (uint16_t)(depth - 1), H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree internal node")
-        if(NULL == (right_internal = H5B2__protect_internal(hdr, dxpl_id, right_addr, internal->node_ptrs[idx + 1].node_nrec, (uint16_t)(depth - 1), H5AC_WRITE)))
+        if(NULL == (right_internal = H5B2__protect_internal(hdr, dxpl_id, right_addr, internal->node_ptrs[idx + 1].node_nrec, (uint16_t)(depth - 1), H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree internal node")
 
         /* More setup for accessing child node information */
@@ -1279,11 +1279,11 @@ H5B2__merge3(H5B2_hdr_t *hdr, hid_t dxpl_id, uint16_t depth,
         right_addr = internal->node_ptrs[idx + 1].addr;
 
         /* Lock B-tree child nodes */
-        if(NULL == (left_leaf = H5B2__protect_leaf(hdr, dxpl_id, left_addr, internal->node_ptrs[idx - 1].node_nrec, H5AC_WRITE)))
+        if(NULL == (left_leaf = H5B2__protect_leaf(hdr, dxpl_id, left_addr, internal->node_ptrs[idx - 1].node_nrec, H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree leaf node")
-        if(NULL == (middle_leaf = H5B2__protect_leaf(hdr, dxpl_id, middle_addr, internal->node_ptrs[idx].node_nrec, H5AC_WRITE)))
+        if(NULL == (middle_leaf = H5B2__protect_leaf(hdr, dxpl_id, middle_addr, internal->node_ptrs[idx].node_nrec, H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree leaf node")
-        if(NULL == (right_leaf = H5B2__protect_leaf(hdr, dxpl_id, right_addr, internal->node_ptrs[idx + 1].node_nrec, H5AC_WRITE)))
+        if(NULL == (right_leaf = H5B2__protect_leaf(hdr, dxpl_id, right_addr, internal->node_ptrs[idx + 1].node_nrec, H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree leaf node")
 
         /* More setup for accessing child node information */
@@ -1460,7 +1460,7 @@ H5B2__swap_leaf(H5B2_hdr_t *hdr, hid_t dxpl_id, uint16_t depth,
         child_addr = internal->node_ptrs[idx].addr;
 
         /* Lock B-tree child nodes */
-        if(NULL == (child_internal = H5B2__protect_internal(hdr, dxpl_id, child_addr, internal->node_ptrs[idx].node_nrec, (uint16_t)(depth - 1), H5AC_WRITE)))
+        if(NULL == (child_internal = H5B2__protect_internal(hdr, dxpl_id, child_addr, internal->node_ptrs[idx].node_nrec, (uint16_t)(depth - 1), H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree internal node")
 
         /* More setup for accessing child node information */
@@ -1475,7 +1475,7 @@ H5B2__swap_leaf(H5B2_hdr_t *hdr, hid_t dxpl_id, uint16_t depth,
         child_addr = internal->node_ptrs[idx].addr;
 
         /* Lock B-tree child node */
-        if(NULL == (child_leaf = H5B2__protect_leaf(hdr, dxpl_id, child_addr, internal->node_ptrs[idx].node_nrec, H5AC_WRITE)))
+        if(NULL == (child_leaf = H5B2__protect_leaf(hdr, dxpl_id, child_addr, internal->node_ptrs[idx].node_nrec, H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree leaf node")
 
         /* More setup for accessing child node information */
@@ -1538,7 +1538,7 @@ H5B2__insert_leaf(H5B2_hdr_t *hdr, hid_t dxpl_id, H5B2_node_ptr_t *curr_node_ptr
     HDassert(H5F_addr_defined(curr_node_ptr->addr));
 
     /* Lock current B-tree node */
-    if(NULL == (leaf = H5B2__protect_leaf(hdr, dxpl_id, curr_node_ptr->addr, curr_node_ptr->node_nrec, H5AC_WRITE)))
+    if(NULL == (leaf = H5B2__protect_leaf(hdr, dxpl_id, curr_node_ptr->addr, curr_node_ptr->node_nrec, H5AC__NO_FLAGS_SET)))
         HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree leaf node")
 
     /* Must have a leaf node with enough space to insert a record now */
@@ -1637,7 +1637,7 @@ H5B2__insert_internal(H5B2_hdr_t *hdr, hid_t dxpl_id, uint16_t depth,
     HDassert(H5F_addr_defined(curr_node_ptr->addr));
 
     /* Lock current B-tree node */
-    if(NULL == (internal = H5B2__protect_internal(hdr, dxpl_id, curr_node_ptr->addr, curr_node_ptr->node_nrec, depth, H5AC_WRITE)))
+    if(NULL == (internal = H5B2__protect_internal(hdr, dxpl_id, curr_node_ptr->addr, curr_node_ptr->node_nrec, depth, H5AC__NO_FLAGS_SET)))
         HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree internal node")
 
     /* Split or redistribute child node pointers, if necessary */
@@ -1834,7 +1834,7 @@ done:
  */
 H5B2_leaf_t *
 H5B2__protect_leaf(H5B2_hdr_t *hdr, hid_t dxpl_id, haddr_t addr, uint16_t nrec,
-    H5AC_protect_t rw)
+    unsigned flags)
 {
     H5B2_leaf_cache_ud_t udata;         /* User-data for callback */
     H5B2_leaf_t *ret_value;             /* Return value */
@@ -1845,13 +1845,16 @@ H5B2__protect_leaf(H5B2_hdr_t *hdr, hid_t dxpl_id, haddr_t addr, uint16_t nrec,
     HDassert(hdr);
     HDassert(H5F_addr_defined(addr));
 
+    /* only H5AC__READ_ONLY_FLAG may appear in flags */
+    HDassert((flags & (unsigned)(~H5AC__READ_ONLY_FLAG)) == 0);
+
     /* Set up user data for callback */
     udata.f = hdr->f;
     udata.hdr = hdr;
     H5_CHECKED_ASSIGN(udata.nrec, uint16_t, nrec, unsigned)
 
     /* Protect the leaf node */
-    if(NULL == (ret_value = (H5B2_leaf_t *)H5AC_protect(hdr->f, dxpl_id, H5AC_BT2_LEAF, addr, &udata, rw)))
+    if(NULL == (ret_value = (H5B2_leaf_t *)H5AC_protect(hdr->f, dxpl_id, H5AC_BT2_LEAF, addr, &udata, flags)))
         HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, NULL, "unable to protect B-tree leaf node")
 
 done:
@@ -1953,7 +1956,7 @@ done:
  */
 H5B2_internal_t *
 H5B2__protect_internal(H5B2_hdr_t *hdr, hid_t dxpl_id, haddr_t addr,
-    uint16_t nrec, uint16_t depth, H5AC_protect_t rw)
+    uint16_t nrec, uint16_t depth, unsigned flags)
 {
     H5B2_internal_cache_ud_t udata;     /* User data to pass through to cache 'deserialize' callback */
     H5B2_internal_t *ret_value;         /* Return value */
@@ -1965,6 +1968,9 @@ H5B2__protect_internal(H5B2_hdr_t *hdr, hid_t dxpl_id, haddr_t addr,
     HDassert(H5F_addr_defined(addr));
     HDassert(depth > 0);
 
+    /* only H5AC__READ_ONLY_FLAG may appear in flags */
+    HDassert((flags & (unsigned)(~H5AC__READ_ONLY_FLAG)) == 0);
+
     /* Set up user data for callback */
     udata.f = hdr->f;
     udata.hdr = hdr;
@@ -1972,7 +1978,7 @@ H5B2__protect_internal(H5B2_hdr_t *hdr, hid_t dxpl_id, haddr_t addr,
     udata.depth = depth;
 
     /* Protect the internal node */
-    if(NULL == (ret_value = (H5B2_internal_t *)H5AC_protect(hdr->f, dxpl_id, H5AC_BT2_INT, addr, &udata, rw)))
+    if(NULL == (ret_value = (H5B2_internal_t *)H5AC_protect(hdr->f, dxpl_id, H5AC_BT2_INT, addr, &udata, flags)))
         HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, NULL, "unable to protect B-tree internal node")
 
 done:
@@ -2021,7 +2027,7 @@ H5B2__iterate_node(H5B2_hdr_t *hdr, hid_t dxpl_id, uint16_t depth,
         H5B2_internal_t *internal;     /* Pointer to internal node */
 
         /* Lock the current B-tree node */
-        if(NULL == (internal = H5B2__protect_internal(hdr, dxpl_id, curr_node->addr, curr_node->node_nrec, depth, H5AC_READ)))
+        if(NULL == (internal = H5B2__protect_internal(hdr, dxpl_id, curr_node->addr, curr_node->node_nrec, depth, H5AC__READ_ONLY_FLAG)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree internal node")
 
         /* Set up information about current node */
@@ -2040,7 +2046,7 @@ H5B2__iterate_node(H5B2_hdr_t *hdr, hid_t dxpl_id, uint16_t depth,
         H5B2_leaf_t *leaf;             /* Pointer to leaf node */
 
         /* Lock the current B-tree node */
-        if(NULL == (leaf = H5B2__protect_leaf(hdr, dxpl_id, curr_node->addr, curr_node->node_nrec, H5AC_READ)))
+        if(NULL == (leaf = H5B2__protect_leaf(hdr, dxpl_id, curr_node->addr, curr_node->node_nrec, H5AC__READ_ONLY_FLAG)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree leaf node")
 
         /* Set up information about current node */
@@ -2125,7 +2131,7 @@ H5B2__remove_leaf(H5B2_hdr_t *hdr, hid_t dxpl_id, H5B2_node_ptr_t *curr_node_ptr
 
     /* Lock current B-tree node */
     leaf_addr = curr_node_ptr->addr;
-    if(NULL == (leaf = H5B2__protect_leaf(hdr, dxpl_id, leaf_addr, curr_node_ptr->node_nrec, H5AC_WRITE)))
+    if(NULL == (leaf = H5B2__protect_leaf(hdr, dxpl_id, leaf_addr, curr_node_ptr->node_nrec, H5AC__NO_FLAGS_SET)))
         HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree leaf node")
 
     /* Sanity check number of records */
@@ -2234,7 +2240,7 @@ H5B2__remove_internal(H5B2_hdr_t *hdr, hid_t dxpl_id, hbool_t *depth_decreased,
 
     /* Lock current B-tree node */
     internal_addr = curr_node_ptr->addr;
-    if(NULL == (internal = H5B2__protect_internal(hdr, dxpl_id, internal_addr, curr_node_ptr->node_nrec, depth, H5AC_WRITE)))
+    if(NULL == (internal = H5B2__protect_internal(hdr, dxpl_id, internal_addr, curr_node_ptr->node_nrec, depth, H5AC__NO_FLAGS_SET)))
         HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree internal node")
 
     /* Determine the correct number of records to merge at */
@@ -2443,7 +2449,7 @@ H5B2__remove_leaf_by_idx(H5B2_hdr_t *hdr, hid_t dxpl_id,
 
     /* Lock B-tree leaf node */
     leaf_addr = curr_node_ptr->addr;
-    if(NULL == (leaf = H5B2__protect_leaf(hdr, dxpl_id, leaf_addr, curr_node_ptr->node_nrec, H5AC_WRITE)))
+    if(NULL == (leaf = H5B2__protect_leaf(hdr, dxpl_id, leaf_addr, curr_node_ptr->node_nrec, H5AC__NO_FLAGS_SET)))
         HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree leaf node")
 
     /* Sanity check number of records */
@@ -2551,7 +2557,7 @@ H5B2__remove_internal_by_idx(H5B2_hdr_t *hdr, hid_t dxpl_id,
 
     /* Lock current B-tree node */
     internal_addr = curr_node_ptr->addr;
-    if(NULL == (internal = H5B2__protect_internal(hdr, dxpl_id, internal_addr, curr_node_ptr->node_nrec, depth, H5AC_WRITE)))
+    if(NULL == (internal = H5B2__protect_internal(hdr, dxpl_id, internal_addr, curr_node_ptr->node_nrec, depth, H5AC__NO_FLAGS_SET)))
         HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree internal node")
     HDassert(internal->nrec == curr_node_ptr->node_nrec);
     HDassert(depth == hdr->depth || internal->nrec > 1);
@@ -2827,7 +2833,7 @@ H5B2__neighbor_leaf(H5B2_hdr_t *hdr, hid_t dxpl_id, H5B2_node_ptr_t *curr_node_p
     HDassert(op);
 
     /* Lock current B-tree node */
-    if(NULL == (leaf = H5B2__protect_leaf(hdr, dxpl_id, curr_node_ptr->addr, curr_node_ptr->node_nrec, H5AC_READ)))
+    if(NULL == (leaf = H5B2__protect_leaf(hdr, dxpl_id, curr_node_ptr->addr, curr_node_ptr->node_nrec, H5AC__READ_ONLY_FLAG)))
         HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree leaf node")
 
     /* Locate node pointer for child */
@@ -2914,7 +2920,7 @@ H5B2__neighbor_internal(H5B2_hdr_t *hdr, hid_t dxpl_id, uint16_t depth,
     HDassert(op);
 
     /* Lock current B-tree node */
-    if(NULL == (internal = H5B2__protect_internal(hdr, dxpl_id, curr_node_ptr->addr, curr_node_ptr->node_nrec, depth, H5AC_READ)))
+    if(NULL == (internal = H5B2__protect_internal(hdr, dxpl_id, curr_node_ptr->addr, curr_node_ptr->node_nrec, depth, H5AC__READ_ONLY_FLAG)))
         HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree internal node")
 
     /* Locate node pointer for child */
@@ -2987,7 +2993,7 @@ H5B2__delete_node(H5B2_hdr_t *hdr, hid_t dxpl_id, uint16_t depth,
         unsigned u;                    /* Local index */
 
         /* Lock the current B-tree node */
-        if(NULL == (internal = H5B2__protect_internal(hdr, dxpl_id, curr_node->addr, curr_node->node_nrec, depth, H5AC_WRITE)))
+        if(NULL == (internal = H5B2__protect_internal(hdr, dxpl_id, curr_node->addr, curr_node->node_nrec, depth, H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree internal node")
 
         /* Set up information about current node */
@@ -3004,7 +3010,7 @@ H5B2__delete_node(H5B2_hdr_t *hdr, hid_t dxpl_id, uint16_t depth,
         H5B2_leaf_t *leaf;             /* Pointer to leaf node */
 
         /* Lock the current B-tree node */
-        if(NULL == (leaf = H5B2__protect_leaf(hdr, dxpl_id, curr_node->addr, curr_node->node_nrec, H5AC_WRITE)))
+        if(NULL == (leaf = H5B2__protect_leaf(hdr, dxpl_id, curr_node->addr, curr_node->node_nrec, H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree leaf node")
 
         /* Set up information about current node */
@@ -3063,7 +3069,7 @@ H5B2__node_size(H5B2_hdr_t *hdr, hid_t dxpl_id, uint16_t depth,
     HDassert(depth > 0);
 
     /* Lock the current B-tree node */
-    if(NULL == (internal = H5B2__protect_internal(hdr, dxpl_id, curr_node->addr, curr_node->node_nrec, depth, H5AC_READ)))
+    if(NULL == (internal = H5B2__protect_internal(hdr, dxpl_id, curr_node->addr, curr_node->node_nrec, depth, H5AC__READ_ONLY_FLAG)))
         HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree internal node")
 
     /* Recursively descend into child nodes, if we are above the "twig" level in the B-tree */
diff --git a/src/H5B2pkg.h b/src/H5B2pkg.h
index a2d32e6..b13c58d 100644
--- a/src/H5B2pkg.h
+++ b/src/H5B2pkg.h
@@ -231,6 +231,7 @@ typedef enum H5B2_nodepos_t {
 /* Callback info for loading a free space header into the cache */
 typedef struct H5B2_hdr_cache_ud_t {
     H5F_t *f;                   /* File that v2 b-tree header is within */
+    haddr_t addr;               /* Address of B-tree header in the file */
     void *ctx_udata;            /* User-data for protecting */
 } H5B2_hdr_cache_ud_t;
 
@@ -305,11 +306,11 @@ H5_DLL herr_t H5B2__hdr_delete(H5B2_hdr_t *hdr, hid_t dxpl_id);
 
 /* Routines for operating on leaf nodes */
 H5B2_leaf_t *H5B2__protect_leaf(H5B2_hdr_t *hdr, hid_t dxpl_id, haddr_t addr,
-    uint16_t nrec, H5AC_protect_t rw);
+    uint16_t nrec, unsigned flags);
 
 /* Routines for operating on internal nodes */
 H5_DLL H5B2_internal_t *H5B2__protect_internal(H5B2_hdr_t *hdr, hid_t dxpl_id,
-    haddr_t addr, uint16_t nrec, uint16_t depth, H5AC_protect_t rw);
+    haddr_t addr, uint16_t nrec, uint16_t depth, unsigned flags);
 
 /* Routines for allocating nodes */
 H5_DLL herr_t H5B2__split_root(H5B2_hdr_t *hdr, hid_t dxpl_id);
@@ -347,7 +348,7 @@ H5_DLL herr_t H5B2__neighbor_leaf(H5B2_hdr_t *hdr, hid_t dxpl_id,
 /* Routines for removing records */
 H5_DLL herr_t H5B2__remove_internal(H5B2_hdr_t *hdr, hid_t dxpl_id,
     hbool_t *depth_decreased, void *swap_loc, uint16_t depth,
-    H5AC_info_t *parent_cache_info, hbool_t *parent_cache_info_dirtied_ptr,
+    H5AC_info_t *parent_cache_info, unsigned *parent_cache_info_flags_ptr,
     H5B2_nodepos_t curr_pos, H5B2_node_ptr_t *curr_node_ptr, void *udata,
     H5B2_remove_t op, void *op_data);
 H5_DLL herr_t H5B2__remove_leaf(H5B2_hdr_t *hdr, hid_t dxpl_id,
@@ -355,8 +356,8 @@ H5_DLL herr_t H5B2__remove_leaf(H5B2_hdr_t *hdr, hid_t dxpl_id,
     void *udata, H5B2_remove_t op, void *op_data);
 H5_DLL herr_t H5B2__remove_internal_by_idx(H5B2_hdr_t *hdr, hid_t dxpl_id,
     hbool_t *depth_decreased, void *swap_loc, uint16_t depth,
-    H5AC_info_t *parent_cache_info, hbool_t *parent_cache_info_dirtied_ptr,
-    H5B2_node_ptr_t *curr_node_ptr, H5B2_nodepos_t curr_pos, hsize_t idx,
+    H5AC_info_t *parent_cache_info, unsigned *parent_cache_info_flags_ptr,
+    H5B2_node_ptr_t *curr_node_ptr, H5B2_nodepos_t curr_pos, hsize_t n,
     H5B2_remove_t op, void *op_data);
 H5_DLL herr_t H5B2__remove_leaf_by_idx(H5B2_hdr_t *hdr, hid_t dxpl_id,
     H5B2_node_ptr_t *curr_node_ptr, H5B2_nodepos_t curr_pos,
diff --git a/src/H5B2test.c b/src/H5B2test.c
index 1d31af8..35771f2 100644
--- a/src/H5B2test.c
+++ b/src/H5B2test.c
@@ -430,7 +430,7 @@ H5B2_get_node_info_test(H5B2_t *bt2, hid_t dxpl_id, void *udata,
         H5B2_node_ptr_t next_node_ptr;      /* Node pointer info for next node */
 
         /* Lock B-tree current node */
-        if(NULL == (internal = H5B2__protect_internal(hdr, dxpl_id, curr_node_ptr.addr, curr_node_ptr.node_nrec, depth, H5AC_READ)))
+        if(NULL == (internal = H5B2__protect_internal(hdr, dxpl_id, curr_node_ptr.addr, curr_node_ptr.node_nrec, depth, H5AC__READ_ONLY_FLAG)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to load B-tree internal node")
 
         /* Locate node pointer for child */
@@ -470,7 +470,7 @@ H5B2_get_node_info_test(H5B2_t *bt2, hid_t dxpl_id, void *udata,
         H5B2_leaf_t *leaf;          /* Pointer to leaf node in B-tree */
 
         /* Lock B-tree leaf node */
-        if(NULL == (leaf = H5B2__protect_leaf(hdr, dxpl_id, curr_node_ptr.addr, curr_node_ptr.node_nrec, H5AC_READ)))
+        if(NULL == (leaf = H5B2__protect_leaf(hdr, dxpl_id, curr_node_ptr.addr, curr_node_ptr.node_nrec, H5AC__READ_ONLY_FLAG)))
             HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to protect B-tree leaf node")
 
         /* Locate record */
diff --git a/src/H5Bcache.c b/src/H5Bcache.c
index a161e88..d071712 100644
--- a/src/H5Bcache.c
+++ b/src/H5Bcache.c
@@ -37,7 +37,6 @@
 #include "H5private.h"		/* Generic Functions			*/
 #include "H5Bpkg.h"		/* B-link trees				*/
 #include "H5Eprivate.h"		/* Error handling		  	*/
-#include "H5MFprivate.h"	/* File memory management		*/
 
 
 /****************/
@@ -55,11 +54,14 @@
 /********************/
 
 /* Metadata cache callbacks */
-static H5B_t *H5B__load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata);
-static herr_t H5B__flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5B_t *b, unsigned H5_ATTR_UNUSED * flags_ptr);
-static herr_t H5B__dest(H5F_t *f, H5B_t *bt);
-static herr_t H5B__clear(H5F_t *f, H5B_t *b, hbool_t destroy);
-static herr_t H5B__compute_size(const H5F_t *f, const H5B_t *bt, size_t *size_ptr);
+static herr_t H5B__get_load_size(const void *udata, size_t *image_len);
+static void *H5B__deserialize(const void *image, size_t len, void *udata,
+    hbool_t *dirty);
+static herr_t H5B__image_len(const void *thing, size_t *image_len, 
+    hbool_t *compressed_ptr, size_t *compressed_image_len_ptr);
+static herr_t H5B__serialize(const H5F_t *f, void *image, size_t len,
+    void *thing);
+static herr_t H5B__free_icr(void *thing);
 
 
 /*********************/
@@ -68,13 +70,19 @@ static herr_t H5B__compute_size(const H5F_t *f, const H5B_t *bt, size_t *size_pt
 
 /* H5B inherits cache-like properties from H5AC */
 const H5AC_class_t H5AC_BT[1] = {{
-    H5AC_BT_ID,
-    (H5AC_load_func_t)H5B__load,
-    (H5AC_flush_func_t)H5B__flush,
-    (H5AC_dest_func_t)H5B__dest,
-    (H5AC_clear_func_t)H5B__clear,
-    (H5AC_notify_func_t)NULL,
-    (H5AC_size_func_t)H5B__compute_size,
+    H5AC_BT_ID,                         /* Metadata client ID */
+    "v1 B-tree",                        /* Metadata client name (for debugging) */
+    H5FD_MEM_BTREE,                     /* File space memory type for client */
+    H5AC__CLASS_NO_FLAGS_SET,           /* Client class behavior flags */
+    H5B__get_load_size,                 /* 'get_load_size' callback */
+    H5B__deserialize,                   /* 'deserialize' callback */
+    H5B__image_len,                     /* 'image_len' callback */
+    NULL,                               /* 'pre_serialize' callback */
+    H5B__serialize,                     /* 'serialize' callback */
+    NULL,                               /* 'notify' callback */
+    H5B__free_icr,                      /* 'free_icr' callback */
+    NULL,				/* 'clear" callback */
+    NULL,                               /* 'fsf_size' callback */
 }};
 
 /*******************/
@@ -84,35 +92,71 @@ const H5AC_class_t H5AC_BT[1] = {{
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5B__load
+ * Function:    H5B__get_load_size
  *
- * Purpose:	Loads a B-tree node from the disk.
+ * Purpose:     Compute the size of the data structure on disk.
+ *
+ * Return:      Non-negative on success/Negative on failure
+ *
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              May 18, 2010
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5B__get_load_size(const void *_udata, size_t *image_len)
+{
+    const H5B_cache_ud_t *udata = (const H5B_cache_ud_t *)_udata;       /* User data for callback */
+    H5B_shared_t *shared;       /* Pointer to shared B-tree info */
+
+    FUNC_ENTER_STATIC_NOERR
+
+    /* Check arguments */
+    HDassert(udata);
+    HDassert(image_len);
+
+    /* Get shared info for B-tree */
+    shared = (H5B_shared_t *)H5UC_GET_OBJ(udata->rc_shared);
+    HDassert(shared);
+
+    /* Set the image length size */
+    *image_len = shared->sizeof_rnode;
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5B__get_load_size() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5B__deserialize
+ *
+ * Purpose:     Deserialize the data structure from disk.
  *
  * Return:	Success:	Pointer to a new B-tree node.
  *		Failure:	NULL
  *
- * Programmer:	Robb Matzke
- *		matzke@llnl.gov
- *		Jun 23 1997
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              Mar 24, 2008
  *
  *-------------------------------------------------------------------------
  */
-static H5B_t *
-H5B__load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
+static void *
+H5B__deserialize(const void *_image, size_t H5_ATTR_UNUSED len, void *_udata,
+    hbool_t H5_ATTR_UNUSED *dirty)
 {
     H5B_t *bt = NULL;           /* Pointer to the deserialized B-tree node */
     H5B_cache_ud_t *udata = (H5B_cache_ud_t *)_udata;       /* User data for callback */
     H5B_shared_t *shared;       /* Pointer to shared B-tree info */
-    const uint8_t *p;           /* Pointer into raw data buffer */
+    const uint8_t *image = (const uint8_t *)_image;     /* Pointer into image buffer */
     uint8_t *native;            /* Pointer to native keys */
     unsigned u;                 /* Local index variable */
     H5B_t *ret_value;           /* Return value */
 
     FUNC_ENTER_STATIC
 
-    /* Check arguments */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
+    /* check arguments */
+    HDassert(image);
     HDassert(udata);
 
     /* Allocate the B-tree node in memory */
@@ -134,53 +178,50 @@ H5B__load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
     if(NULL == (bt->child = H5FL_SEQ_MALLOC(haddr_t, (size_t)shared->two_k)))
 	HGOTO_ERROR(H5E_BTREE, H5E_CANTALLOC, NULL, "can't allocate buffer for child addresses")
 
-    if(H5F_block_read(f, H5FD_MEM_BTREE, addr, shared->sizeof_rnode, dxpl_id, shared->page) < 0)
-	HGOTO_ERROR(H5E_BTREE, H5E_READERROR, NULL, "can't read B-tree node")
-
-    /* Set the pointer into the raw data buffer */
-    p = shared->page;
-
     /* magic number */
-    if(HDmemcmp(p, H5B_MAGIC, (size_t)H5_SIZEOF_MAGIC))
+    if(HDmemcmp(image, H5B_MAGIC, (size_t)H5_SIZEOF_MAGIC))
 	HGOTO_ERROR(H5E_BTREE, H5E_BADVALUE, NULL, "wrong B-tree signature")
-    p += 4;
+    image += H5_SIZEOF_MAGIC;
 
     /* node type and level */
-    if(*p++ != (uint8_t)udata->type->id)
+    if(*image++ != (uint8_t)udata->type->id)
 	HGOTO_ERROR(H5E_BTREE, H5E_CANTLOAD, NULL, "incorrect B-tree node type")
-    bt->level = *p++;
+    bt->level = *image++;
 
     /* entries used */
-    UINT16DECODE(p, bt->nchildren);
+    UINT16DECODE(image, bt->nchildren);
 
     /* Check if bt->nchildren is greater than two_k */
     if(bt->nchildren > shared->two_k)
         HGOTO_ERROR(H5E_BTREE, H5E_BADVALUE, NULL, "number of children is greater than maximum")
 
     /* sibling pointers */
-    H5F_addr_decode(udata->f, (const uint8_t **)&p, &(bt->left));
-    H5F_addr_decode(udata->f, (const uint8_t **)&p, &(bt->right));
+    H5F_addr_decode(udata->f, (const uint8_t **)&image, &(bt->left));
+    H5F_addr_decode(udata->f, (const uint8_t **)&image, &(bt->right));
 
     /* the child/key pairs */
     native = bt->native;
     for(u = 0; u < bt->nchildren; u++) {
         /* Decode native key value */
-        if((udata->type->decode)(shared, p, native) < 0)
+        if((udata->type->decode)(shared, image, native) < 0)
             HGOTO_ERROR(H5E_BTREE, H5E_CANTDECODE, NULL, "unable to decode key")
-        p += shared->sizeof_rkey;
+        image += shared->sizeof_rkey;
         native += udata->type->sizeof_nkey;
 
         /* Decode address value */
-        H5F_addr_decode(udata->f, (const uint8_t **)&p, bt->child + u);
+        H5F_addr_decode(udata->f, (const uint8_t **)&image, bt->child + u);
     } /* end for */
 
     /* Decode final key */
     if(bt->nchildren > 0) {
         /* Decode native key value */
-        if((udata->type->decode)(shared, p, native) < 0)
+        if((udata->type->decode)(shared, image, native) < 0)
             HGOTO_ERROR(H5E_BTREE, H5E_CANTDECODE, NULL, "unable to decode key")
     } /* end if */
 
+    /* Sanity check */
+    HDassert((size_t)((const uint8_t *)image - (const uint8_t *)_image) <= len);
+
     /* Set return value */
     ret_value = bt;
 
@@ -190,223 +231,157 @@ done:
             HDONE_ERROR(H5E_BTREE, H5E_CANTFREE, NULL, "unable to destroy B-tree node")
 
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5B__load() */  /*lint !e818 Can't make udata a pointer to const */
+} /* end H5B__deserialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5B__flush
+ * Function:    H5B__image_len
  *
- * Purpose:	Flushes a dirty B-tree node to disk.
+ * Purpose:     Compute the size of the data structure on disk.
  *
  * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Robb Matzke
- *		matzke@llnl.gov
- *		Jun 23 1997
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              May 20, 2010
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5B__flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5B_t *bt, unsigned H5_ATTR_UNUSED * flags_ptr)
+H5B__image_len(const void *_thing, size_t *image_len,
+    hbool_t H5_ATTR_UNUSED *compressed_ptr, size_t H5_ATTR_UNUSED *compressed_image_len_ptr)
 {
+    const H5B_t *bt = (const H5B_t *)_thing;        /* Pointer to the B-tree node */
     H5B_shared_t *shared;       /* Pointer to shared B-tree info */
-    herr_t      ret_value = SUCCEED;    /* Return value */
 
-    FUNC_ENTER_STATIC
+    FUNC_ENTER_STATIC_NOERR
 
-    /* check arguments */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
+    /* Check arguments */
     HDassert(bt);
+    HDassert(image_len);
+
+    /* Get shared info for B-tree */
     shared = (H5B_shared_t *)H5UC_GET_OBJ(bt->rc_shared);
     HDassert(shared);
-    HDassert(shared->type);
-    HDassert(shared->type->encode);
-
-    if(bt->cache_info.is_dirty) {
-        uint8_t    *p;              /* Pointer into raw data buffer */
-        uint8_t    *native;         /* Pointer to native keys */
-        unsigned    u;              /* Local index variable */
-
-        p = shared->page;
-
-        /* magic number */
-        HDmemcpy(p, H5B_MAGIC, (size_t)H5_SIZEOF_MAGIC);
-        p += 4;
-
-        /* node type and level */
-        *p++ = (uint8_t)shared->type->id;
-        H5_CHECK_OVERFLOW(bt->level, unsigned, uint8_t);
-        *p++ = (uint8_t)bt->level;
-
-        /* entries used */
-        UINT16ENCODE(p, bt->nchildren);
-
-        /* sibling pointers */
-        H5F_addr_encode(f, &p, bt->left);
-        H5F_addr_encode(f, &p, bt->right);
-
-        /* child keys and pointers */
-        native = bt->native;
-        for(u = 0; u < bt->nchildren; ++u) {
-            /* encode the key */
-            if(shared->type->encode(shared, p, native) < 0)
-                HGOTO_ERROR(H5E_BTREE, H5E_CANTENCODE, FAIL, "unable to encode B-tree key")
-            p += shared->sizeof_rkey;
-            native += shared->type->sizeof_nkey;
-
-            /* encode the child address */
-            H5F_addr_encode(f, &p, bt->child[u]);
-        } /* end for */
-        if(bt->nchildren > 0) {
-            /* Encode the final key */
-            if(shared->type->encode(shared, p, native) < 0)
-                HGOTO_ERROR(H5E_BTREE, H5E_CANTENCODE, FAIL, "unable to encode B-tree key")
-        } /* end if */
-
-	/*
-         * Write the disk page.	We always write the header, but we don't
-         * bother writing data for the child entries that don't exist or
-         * for the final unchanged children.
-	 */
-	if(H5F_block_write(f, H5FD_MEM_BTREE, addr, shared->sizeof_rnode, dxpl_id, shared->page) < 0)
-	    HGOTO_ERROR(H5E_BTREE, H5E_CANTFLUSH, FAIL, "unable to save B-tree node to disk")
-
-	bt->cache_info.is_dirty = FALSE;
-    } /* end if */
 
-    if(destroy)
-        if(H5B__dest(f, bt) < 0)
-	    HGOTO_ERROR(H5E_BTREE, H5E_CANTFREE, FAIL, "unable to destroy B-tree node")
+    /* Set the image length size */
+    *image_len = shared->sizeof_rnode;
 
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5B__flush() */
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5B__image_len() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5B__dest
+ * Function:    H5B__serialize
  *
- * Purpose:	Destroys a B-tree node in memory.
+ * Purpose:     Serialize the data structure for writing to disk.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Jan 15 2003
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              Mar 24, 2008
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5B__dest(H5F_t *f, H5B_t *bt)
+H5B__serialize(const H5F_t *f, void *_image, size_t H5_ATTR_UNUSED len,
+    void *_thing)
 {
-    herr_t ret_value = SUCCEED;         /* Return value */
+    H5B_t *bt = (H5B_t *)_thing;        /* Pointer to the B-tree node */
+    H5B_shared_t *shared;               /* Pointer to shared B-tree info */
+    uint8_t    *image = (uint8_t *)_image;      /* Pointer into image buffer */
+    uint8_t    *native;                 /* Pointer to native keys */
+    unsigned    u;                      /* Local index counter */
+    herr_t      ret_value = SUCCEED;    /* Return value */
 
     FUNC_ENTER_STATIC
 
-    /*
-     * Check arguments.
-     */
-    HDassert(f);
+    /* check arguments */
+    HDassert(image);
     HDassert(bt);
     HDassert(bt->rc_shared);
+    shared = (H5B_shared_t *)H5UC_GET_OBJ(bt->rc_shared);
+    HDassert(shared);
+    HDassert(shared->type);
+    HDassert(shared->type->encode);
 
-    /* If we're going to free the space on disk, the address must be valid */
-    HDassert(!bt->cache_info.free_file_space_on_destroy || H5F_addr_defined(bt->cache_info.addr));
+    /* magic number */
+    HDmemcpy(image, H5B_MAGIC, (size_t)H5_SIZEOF_MAGIC);
+    image += 4;
 
-    /* Check for freeing file space for B-tree node */
-    if(bt->cache_info.free_file_space_on_destroy) {
-        H5B_shared_t *shared;               /* Pointer to shared B-tree info */
+    /* node type and level */
+    *image++ = (uint8_t)shared->type->id;
+    H5_CHECK_OVERFLOW(bt->level, unsigned, uint8_t);
+    *image++ = (uint8_t)bt->level;
 
-        /* Get the pointer to the shared B-tree info */
-        shared = (H5B_shared_t *)H5UC_GET_OBJ(bt->rc_shared);
-        HDassert(shared);
+    /* entries used */
+    UINT16ENCODE(image, bt->nchildren);
 
-        /* Release the space on disk */
-        /* (XXX: Nasty usage of internal DXPL value! -QAK) */
-        if(H5MF_xfree(f, H5FD_MEM_BTREE, H5AC_dxpl_id, bt->cache_info.addr, (hsize_t)shared->sizeof_rnode) < 0)
-            HGOTO_ERROR(H5E_BTREE, H5E_CANTFREE, FAIL, "unable to free B-tree node")
+    /* sibling pointers */
+    H5F_addr_encode(f, &image, bt->left);
+    H5F_addr_encode(f, &image, bt->right);
+
+    /* child keys and pointers */
+    native = bt->native;
+    for(u = 0; u < bt->nchildren; ++u) {
+        /* encode the key */
+        if(shared->type->encode(shared, image, native) < 0)
+            HGOTO_ERROR(H5E_BTREE, H5E_CANTENCODE, FAIL, "unable to encode B-tree key")
+        image += shared->sizeof_rkey;
+        native += shared->type->sizeof_nkey;
+
+        /* encode the child address */
+        H5F_addr_encode(f, &image, bt->child[u]);
+    } /* end for */
+    if(bt->nchildren > 0) {
+        /* Encode the final key */
+        if(shared->type->encode(shared, image, native) < 0)
+            HGOTO_ERROR(H5E_BTREE, H5E_CANTENCODE, FAIL, "unable to encode B-tree key")
+        image += shared->sizeof_rkey;
     } /* end if */
 
-    /* Destroy B-tree node */
-    if(H5B__node_dest(bt) < 0)
-        HGOTO_ERROR(H5E_BTREE, H5E_CANTFREE, FAIL, "unable to destroy B-tree node")
+    /* Sanity check */
+    HDassert((size_t)(image - (uint8_t *)_image) <= len);
+
+#ifdef H5_CLEAR_MEMORY
+    /* Clear rest of node */
+    HDmemset(image, 0, len - (size_t)(image - (uint8_t *)_image));
+#endif /* H5_CLEAR_MEMORY */
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5B__dest() */
+} /* end H5B__serialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5B__clear
+ * Function:    H5B__free_icr
  *
- * Purpose:	Mark a B-tree node in memory as non-dirty.
+ * Purpose:     Destroy/release an "in core representation" of a data structure
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Mar 20 2003
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              Mar 26, 2008
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5B__clear(H5F_t *f, H5B_t *bt, hbool_t destroy)
+H5B__free_icr(void *thing)
 {
-    herr_t ret_value = SUCCEED;
+    herr_t      ret_value = SUCCEED;    /* Return value */
 
     FUNC_ENTER_STATIC
 
-    /*
-     * Check arguments.
-     */
-    HDassert(bt);
-
-    /* Reset the dirty flag.  */
-    bt->cache_info.is_dirty = FALSE;
+    /* Check arguments */
+    HDassert(thing);
 
-    if(destroy)
-        if(H5B__dest(f, bt) < 0)
-	    HGOTO_ERROR(H5E_BTREE, H5E_CANTFREE, FAIL, "unable to destroy B-tree node")
+    /* Destroy B-tree node */
+    if(H5B__node_dest((H5B_t *)thing) < 0)
+        HGOTO_ERROR(H5E_BTREE, H5E_CANTFREE, FAIL, "unable to destroy B-tree node")
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5B__clear() */
-
-
-/*-------------------------------------------------------------------------
- * Function:	H5B__compute_size
- *
- * Purpose:	Compute the size in bytes of the specified instance of
- *		H5B_t on disk, and return it in *len_ptr.  On failure,
- *		the value of *len_ptr is undefined.
- *
- * Return:	Non-negative on success/Negative on failure
- *
- * Programmer:	John Mainzer
- *		5/13/04
- *
- *-------------------------------------------------------------------------
- */
-static herr_t
-H5B__compute_size(const H5F_t H5_ATTR_UNUSED *f, const H5B_t *bt, size_t *size_ptr)
-{
-    H5B_shared_t        *shared;        /* Pointer to shared B-tree info */
-
-    FUNC_ENTER_STATIC_NOERR
-
-    /* check arguments */
-    HDassert(f);
-    HDassert(bt);
-    HDassert(bt->rc_shared);
-    shared = (H5B_shared_t *)H5UC_GET_OBJ(bt->rc_shared);
-    HDassert(shared);
-    HDassert(shared->type);
-    HDassert(size_ptr);
-
-    /* Set size value */
-    *size_ptr = shared->sizeof_rnode;
-
-    FUNC_LEAVE_NOAPI(SUCCEED)
-} /* H5B__compute_size() */
+} /* end H5B__free_icr() */
 
diff --git a/src/H5Bdbg.c b/src/H5Bdbg.c
index 526a647..e6d54dc 100644
--- a/src/H5Bdbg.c
+++ b/src/H5Bdbg.c
@@ -89,7 +89,7 @@ H5B_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE *stream, int indent, int f
     cache_udata.f = f;
     cache_udata.type = type;
     cache_udata.rc_shared = rc_shared;
-    if(NULL == (bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, addr, &cache_udata, H5AC_READ)))
+    if(NULL == (bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, addr, &cache_udata, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_BTREE, H5E_CANTPROTECT, FAIL, "unable to load B-tree node")
 
     /*
@@ -206,7 +206,7 @@ H5B__assert(H5F_t *f, hid_t dxpl_id, haddr_t addr, const H5B_class_t *type, void
     cache_udata.f = f;
     cache_udata.type = type;
     cache_udata.rc_shared = rc_shared;
-    bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, addr, &cache_udata, H5AC_READ);
+    bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, addr, &cache_udata, H5AC__READ_ONLY_FLAG);
     HDassert(bt);
     shared = (H5B_shared_t *)H5UC_GET_OBJ(bt->rc_shared);
     HDassert(shared);
@@ -227,7 +227,7 @@ H5B__assert(H5F_t *f, hid_t dxpl_id, haddr_t addr, const H5B_class_t *type, void
      * test.
      */
     for(ncell = 0; cur; ncell++) {
-	bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, cur->addr, &cache_udata, H5AC_READ);
+	bt = (H5B_t *)H5AC_protect(f, dxpl_id, H5AC_BT, cur->addr, &cache_udata, H5AC__READ_ONLY_FLAG);
 	HDassert(bt);
 
 	/* Check node header */
diff --git a/src/H5C.c b/src/H5C.c
index 5cdd65f..c478173 100644
--- a/src/H5C.c
+++ b/src/H5C.c
@@ -41,7 +41,7 @@
  *
  *	Code Changes:
  *
- *	 - Remove extra functionality in H5C_flush_single_entry()?
+ *	 - Remove extra functionality in H5C__flush_single_entry()?
  *
  *	 - Change protect/unprotect to lock/unlock.
  *
@@ -70,60 +70,68 @@
  *
  **************************************************************************/
 
+/****************/
+/* Module Setup */
+/****************/
+
 #define H5C_PACKAGE		/*suppress error about including H5Cpkg   */
 #define H5F_PACKAGE		/*suppress error about including H5Fpkg	  */
 
 
+/***********/
+/* Headers */
+/***********/
 #include "H5private.h"		/* Generic Functions			*/
 #ifdef H5_HAVE_PARALLEL
 #include "H5ACprivate.h"        /* Metadata cache                       */
 #endif /* H5_HAVE_PARALLEL */
 #include "H5Cpkg.h"		/* Cache				*/
-#include "H5Dprivate.h"		/* Dataset functions			*/
 #include "H5Eprivate.h"		/* Error handling		  	*/
 #include "H5Fpkg.h"		/* Files				*/
 #include "H5FDprivate.h"	/* File drivers				*/
 #include "H5FLprivate.h"	/* Free Lists                           */
 #include "H5Iprivate.h"		/* IDs			  		*/
+#include "H5MFprivate.h"	/* File memory management		*/
 #include "H5MMprivate.h"	/* Memory management			*/
 #include "H5Pprivate.h"         /* Property lists                       */
 #include "H5SLprivate.h"	/* Skip lists				*/
 
 
-/*
- * Private file-scope variables.
- */
+/****************/
+/* Local Macros */
+/****************/
+#if H5C_DO_MEMORY_SANITY_CHECKS
+#define H5C_IMAGE_EXTRA_SPACE 8
+#define H5C_IMAGE_SANITY_VALUE "DeadBeef"
+#else /* H5C_DO_MEMORY_SANITY_CHECKS */
+#define H5C_IMAGE_EXTRA_SPACE 0
+#endif /* H5C_DO_MEMORY_SANITY_CHECKS */
 
-/* Declare a free list to manage the H5C_t struct */
-H5FL_DEFINE_STATIC(H5C_t);
+/******************/
+/* Local Typedefs */
+/******************/
 
 
-/*
- * Private file-scope function declarations:
- */
+/********************/
+/* Local Prototypes */
+/********************/
 
 static herr_t H5C__auto_adjust_cache_size(H5F_t * f,
-                                          hid_t primary_dxpl_id,
-                                          hid_t secondary_dxpl_id,
-                                          hbool_t write_permitted,
-                                          hbool_t * first_flush_ptr);
+                                          hid_t dxpl_id,
+                                          hbool_t write_permitted);
 
 static herr_t H5C__autoadjust__ageout(H5F_t * f,
+                                      hid_t dxpl_id,
                                       double hit_rate,
                                       enum H5C_resize_status * status_ptr,
                                       size_t * new_max_cache_size_ptr,
-                                      hid_t primary_dxpl_id,
-                                      hid_t secondary_dxpl_id,
-                                      hbool_t write_permitted,
-                                      hbool_t * first_flush_ptr);
+                                      hbool_t write_permitted);
 
 static herr_t H5C__autoadjust__ageout__cycle_epoch_marker(H5C_t * cache_ptr);
 
 static herr_t H5C__autoadjust__ageout__evict_aged_out_entries(H5F_t * f,
-                                                    hid_t primary_dxpl_id,
-                                                    hid_t secondary_dxpl_id,
-                                                    hbool_t write_permitted,
-                                                    hbool_t * first_flush_ptr);
+                                                       hid_t dxpl_id,
+                                                       hbool_t write_permitted);
 
 static herr_t H5C__autoadjust__ageout__insert_new_marker(H5C_t * cache_ptr);
 
@@ -135,19 +143,9 @@ static herr_t H5C__flash_increase_cache_size(H5C_t * cache_ptr,
                                              size_t old_entry_size,
                                              size_t new_entry_size);
 
-static herr_t H5C_flush_single_entry(H5F_t *       	 f,
-                                     hid_t               primary_dxpl_id,
-                                     hid_t               secondary_dxpl_id,
-                                     const H5C_class_t * type_ptr,
-                                     haddr_t             addr,
-                                     unsigned            flags,
-                                     hbool_t *           first_flush_ptr,
-                                     hbool_t    del_entry_from_slist_on_destroy);
-
-static herr_t H5C_flush_invalidate_cache(H5F_t *  f,
-	                                 hid_t    primary_dxpl_id,
-				         hid_t    secondary_dxpl_id,
-					 unsigned flags);
+static herr_t H5C_flush_invalidate_cache(const H5F_t *  f,
+                                          hid_t    dxpl_id,
+			                  unsigned flags);
 
 static void * H5C_load_entry(H5F_t *             f,
                              hid_t               dxpl_id,
@@ -156,19 +154,16 @@ static void * H5C_load_entry(H5F_t *             f,
                              void *              udata);
 
 static herr_t H5C_make_space_in_cache(H5F_t * f,
-                                      hid_t   primary_dxpl_id,
-                                      hid_t   secondary_dxpl_id,
-                                      size_t  space_needed,
-                                      hbool_t write_permitted,
-                                      hbool_t * first_flush_ptr);
+                                      hid_t   dxpl_id,
+       	                              size_t  space_needed,
+                                      hbool_t write_permitted);
 
 static herr_t H5C_tag_entry(H5C_t * cache_ptr, 
                             H5C_cache_entry_t * entry_ptr,
                             hid_t dxpl_id);
 
 static herr_t H5C_flush_tagged_entries(H5F_t * f, 
-                                       hid_t primary_dxpl_id, 
-                                       hid_t secondary_dxpl_id, 
+                                       hid_t dxpl_id, 
                                        H5C_t * cache_ptr, 
                                        haddr_t tag);
 
@@ -176,20 +171,46 @@ static herr_t H5C_mark_tagged_entries(H5C_t * cache_ptr,
                                       haddr_t tag);
 
 static herr_t H5C_flush_marked_entries(H5F_t * f, 
-                                       hid_t primary_dxpl_id, 
-                                       hid_t secondary_dxpl_id, 
-                                       H5C_t * cache_ptr);
+                                       hid_t dxpl_id);
 
 #if H5C_DO_TAGGING_SANITY_CHECKS
 static herr_t H5C_verify_tag(int id, haddr_t tag);
 #endif
 
+#if H5C_DO_SLIST_SANITY_CHECKS
+static hbool_t H5C_entry_in_skip_list(H5C_t * cache_ptr, 
+                                      H5C_cache_entry_t *target_ptr);
+#endif /* H5C_DO_SLIST_SANITY_CHECKS */
+
 #if H5C_DO_EXTREME_SANITY_CHECKS
 static herr_t H5C_validate_lru_list(H5C_t * cache_ptr);
 static herr_t H5C_validate_pinned_entry_list(H5C_t * cache_ptr);
 static herr_t H5C_validate_protected_entry_list(H5C_t * cache_ptr);
 #endif /* H5C_DO_EXTREME_SANITY_CHECKS */
 
+#if 0 /* debugging routines */
+herr_t H5C_dump_cache(H5C_t * cache_ptr, const char *  cache_name);
+herr_t H5C_dump_cache_skip_list(H5C_t * cache_ptr, char * calling_fcn);
+#endif /* debugging routines */
+
+/*********************/
+/* Package Variables */
+/*********************/
+
+
+/*****************************/
+/* Library Private Variables */
+/*****************************/
+
+
+/*******************/
+/* Local Variables */
+/*******************/
+
+/* Declare a free list to manage the H5C_t struct */
+H5FL_DEFINE_STATIC(H5C_t);
+
+
 
 /****************************************************************************
  *
@@ -208,25 +229,53 @@ static herr_t H5C_validate_protected_entry_list(H5C_t * cache_ptr);
 
 #define H5C__EPOCH_MARKER_TYPE	H5C__MAX_NUM_TYPE_IDS
 
-static void *H5C_epoch_marker_load(H5F_t *f, hid_t dxpl_id, haddr_t addr,
-                                   void *udata);
-static herr_t H5C_epoch_marker_flush(H5F_t *f, hid_t dxpl_id, hbool_t dest,
-                                     haddr_t addr, void *thing,
-				     unsigned *flags_ptr);
-static herr_t H5C_epoch_marker_dest(H5F_t *f, void *thing);
-static herr_t H5C_epoch_marker_clear(H5F_t *f, void *thing, hbool_t dest);
-static herr_t H5C_epoch_marker_notify(H5C_notify_action_t action, void *thing);
-static herr_t H5C_epoch_marker_size(const H5F_t *f, const void *thing, size_t *size_ptr);
+static herr_t H5C__epoch_marker_get_load_size(const void *udata_ptr,
+		                            size_t *image_len_ptr);
+static void * H5C__epoch_marker_deserialize(const void * image_ptr,
+		                            size_t len,
+			                    void * udata,
+			                    hbool_t * dirty_ptr);
+static herr_t H5C__epoch_marker_image_len(const void * thing,
+		                          size_t *image_len_ptr,
+                                          hbool_t *compressed_ptr,
+                                          size_t *compressed_len_ptr);
+static herr_t H5C__epoch_marker_pre_serialize(const H5F_t *f,
+		                             hid_t dxpl_id,
+                                             void * thing,
+                                             haddr_t addr,
+		                             size_t len,
+					     size_t compressed_len,
+		                             haddr_t * new_addr_ptr,
+		                             size_t * new_len_ptr,
+					     size_t * new_compressed_len_ptr,
+		                             unsigned * flags_ptr);
+static herr_t H5C__epoch_marker_serialize(const H5F_t *f,
+		                          void * image_ptr,
+		                          size_t len,
+                                          void * thing);
+static herr_t H5C__epoch_marker_notify(H5C_notify_action_t action, void *thing);
+static herr_t H5C__epoch_marker_free_icr(void * thing);
+
+static herr_t H5C__epoch_marker_clear(const H5F_t *f, void * thing, 
+                                      hbool_t about_to_destroy);
+static herr_t H5C__epoch_marker_fsf_size(const void H5_ATTR_UNUSED * thing, 
+                                         size_t H5_ATTR_UNUSED * fsf_size_ptr);
 
 const H5C_class_t epoch_marker_class =
 {
-    /* id    = */ H5C__EPOCH_MARKER_TYPE,
-    /* load  = */ &H5C_epoch_marker_load,
-    /* flush = */ &H5C_epoch_marker_flush,
-    /* dest  = */ &H5C_epoch_marker_dest,
-    /* clear = */ &H5C_epoch_marker_clear,
-    /* notify = */&H5C_epoch_marker_notify,
-    /* size  = */ &H5C_epoch_marker_size
+    /* id               = */ H5C__EPOCH_MARKER_TYPE,
+    /* name             = */ "epoch marker",
+    /* mem_type         = */ H5FD_MEM_DEFAULT, /* value doesn't matter */
+    /* flags		= */ H5AC__CLASS_NO_FLAGS_SET,
+    /* get_load_size    = */ H5C__epoch_marker_get_load_size,
+    /* deserialize      = */ H5C__epoch_marker_deserialize,
+    /* image_len        = */ H5C__epoch_marker_image_len,
+    /* pre_serialize    = */ H5C__epoch_marker_pre_serialize,
+    /* serialize        = */ H5C__epoch_marker_serialize,
+    /* notify           = */ H5C__epoch_marker_notify,
+    /* free_icr         = */ H5C__epoch_marker_free_icr,
+    /* clear            = */ H5C__epoch_marker_clear,
+    /* fsf_size         = */ H5C__epoch_marker_fsf_size,
 };
 
 
@@ -239,848 +288,114 @@ const H5C_class_t epoch_marker_class =
  *                                                     JRM - 11/16/04
  *
  ***************************************************************************/
-
-static void *
-H5C_epoch_marker_load(H5F_t H5_ATTR_UNUSED * f,
-                      hid_t H5_ATTR_UNUSED dxpl_id,
-                      haddr_t H5_ATTR_UNUSED addr,
-                      void H5_ATTR_UNUSED * udata)
+static herr_t
+H5C__epoch_marker_get_load_size(const void H5_ATTR_UNUSED *udata_ptr,
+    size_t H5_ATTR_UNUSED *image_len_ptr)
 {
-    void * ret_value = NULL;      /* Return value */
+    FUNC_ENTER_STATIC_NOERR /* Yes, even though this pushes an error on the stack */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    HERROR(H5E_CACHE, H5E_SYSTEM, "called unreachable fcn.");
 
-    HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, NULL, "called unreachable fcn.")
+    FUNC_LEAVE_NOAPI(FAIL)
+} /* end H5C__epoch_marker_get_load_size() */
 
-done:
+
+static void *
+H5C__epoch_marker_deserialize(const void H5_ATTR_UNUSED * image_ptr, size_t H5_ATTR_UNUSED len,
+    void H5_ATTR_UNUSED * udata, hbool_t H5_ATTR_UNUSED * dirty_ptr)
+{
+    FUNC_ENTER_STATIC_NOERR /* Yes, even though this pushes an error on the stack */
 
-    FUNC_LEAVE_NOAPI(ret_value)
-}
+    HERROR(H5E_CACHE, H5E_SYSTEM, "called unreachable fcn.");
 
+    FUNC_LEAVE_NOAPI(NULL)
+} /* end H5C__epoch_marker_deserialize() */
 
 
 static herr_t
-H5C_epoch_marker_flush(H5F_t H5_ATTR_UNUSED *f,
-                       hid_t H5_ATTR_UNUSED dxpl_id,
-                       hbool_t H5_ATTR_UNUSED dest,
-                       haddr_t H5_ATTR_UNUSED addr,
-                       void H5_ATTR_UNUSED *thing,
-		       unsigned H5_ATTR_UNUSED * flags_ptr)
+H5C__epoch_marker_image_len(const void H5_ATTR_UNUSED *thing,
+    size_t H5_ATTR_UNUSED *image_len_ptr, hbool_t H5_ATTR_UNUSED *compressed_ptr,
+    size_t H5_ATTR_UNUSED *compressed_len_ptr)
 {
-    herr_t ret_value = FAIL;      /* Return value */
-
-    FUNC_ENTER_NOAPI_NOINIT
-
-    HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "called unreachable fcn.")
+    FUNC_ENTER_STATIC_NOERR /* Yes, even though this pushes an error on the stack */
 
-done:
-
-    FUNC_LEAVE_NOAPI(ret_value)
-}
+    HERROR(H5E_CACHE, H5E_SYSTEM, "called unreachable fcn.");
 
+    FUNC_LEAVE_NOAPI(FAIL)
+} /* end H5C__epoch_marker_image_len() */
 
 
 static herr_t
-H5C_epoch_marker_dest(H5F_t H5_ATTR_UNUSED * f,
-                      void H5_ATTR_UNUSED * thing)
+H5C__epoch_marker_pre_serialize(const H5F_t H5_ATTR_UNUSED *f, hid_t H5_ATTR_UNUSED dxpl_id,
+    void H5_ATTR_UNUSED *thing, haddr_t H5_ATTR_UNUSED addr, size_t H5_ATTR_UNUSED len,
+    size_t H5_ATTR_UNUSED compressed_len, haddr_t H5_ATTR_UNUSED *new_addr_ptr, 
+    size_t H5_ATTR_UNUSED *new_len_ptr, size_t H5_ATTR_UNUSED *new_compressed_len_ptr,
+    unsigned H5_ATTR_UNUSED *flags_ptr)
 {
-    herr_t ret_value = FAIL;      /* Return value */
-
-    FUNC_ENTER_NOAPI_NOINIT
-
-    HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "called unreachable fcn.")
+    FUNC_ENTER_STATIC_NOERR /* Yes, even though this pushes an error on the stack */
 
-done:
+    HERROR(H5E_CACHE, H5E_SYSTEM, "called unreachable fcn.");
 
-    FUNC_LEAVE_NOAPI(ret_value)
-}
+    FUNC_LEAVE_NOAPI(FAIL)
+} /* end H5C__epoch_marker_pre_serialize() */
 
+
 static herr_t
-H5C_epoch_marker_clear(H5F_t H5_ATTR_UNUSED * f,
-                       void H5_ATTR_UNUSED * thing,
-                       hbool_t H5_ATTR_UNUSED dest)
+H5C__epoch_marker_serialize(const H5F_t H5_ATTR_UNUSED *f, void H5_ATTR_UNUSED *image_ptr,
+    size_t H5_ATTR_UNUSED len, void H5_ATTR_UNUSED *thing)
 {
-    herr_t ret_value = FAIL;      /* Return value */
-
-    FUNC_ENTER_NOAPI_NOINIT
-
-    HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "called unreachable fcn.")
+    FUNC_ENTER_STATIC_NOERR /* Yes, even though this pushes an error on the stack */
 
-done:
+    HERROR(H5E_CACHE, H5E_SYSTEM, "called unreachable fcn.");
 
-    FUNC_LEAVE_NOAPI(ret_value)
-}
+    FUNC_LEAVE_NOAPI(FAIL)
+} /* end H5C__epoch_marker_serialize() */
 
+
 static herr_t
-H5C_epoch_marker_notify(H5C_notify_action_t H5_ATTR_UNUSED action,
+H5C__epoch_marker_notify(H5C_notify_action_t H5_ATTR_UNUSED action,
                        void H5_ATTR_UNUSED * thing)
 {
-    herr_t ret_value = FAIL;      /* Return value */
+    FUNC_ENTER_STATIC_NOERR /* Yes, even though this pushes an error on the stack */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    HERROR(H5E_CACHE, H5E_SYSTEM, "called unreachable fcn.");
 
-    HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "called unreachable fcn.")
-
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-}
+    FUNC_LEAVE_NOAPI(FAIL)
+} /* end H5C__epoch_marker_notify() */
 
+
 static herr_t
-H5C_epoch_marker_size(const H5F_t H5_ATTR_UNUSED * f,
-                      const void H5_ATTR_UNUSED * thing,
-                      size_t H5_ATTR_UNUSED * size_ptr)
+H5C__epoch_marker_free_icr(void H5_ATTR_UNUSED * thing)
 {
-    herr_t ret_value = FAIL;      /* Return value */
+    FUNC_ENTER_STATIC_NOERR /* Yes, even though this pushes an error on the stack */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    HERROR(H5E_CACHE, H5E_SYSTEM, "called unreachable fcn.");
 
-    HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "called unreachable fcn.")
-
-done:
-
-    FUNC_LEAVE_NOAPI(ret_value)
-}
+    FUNC_LEAVE_NOAPI(FAIL)
+} /* end H5C__epoch_marker_free_icr() */
 
 
-/*-------------------------------------------------------------------------
- * Function:    H5C_apply_candidate_list
- *
- * Purpose:     Apply the supplied candidate list.
- *
- *		We used to do this by simply having each process write 
- *		every mpi_size-th entry in the candidate list, starting 
- *		at index mpi_rank, and mark all the others clean.  
- *
- *		However, this can cause unnecessary contention in a file 
- *		system by increasing the number of processes writing to 
- *		adjacent locations in the HDF5 file.
- *
- *		To attempt to minimize this, we now arange matters such 
- *		that each process writes n adjacent entries in the 
- *		candidate list, and marks all others clean.  We must do
- *		this in such a fashion as to guarantee that each entry 
- *		on the candidate list is written by exactly one process, 
- *		and marked clean by all others.  
- *
- *		To do this, first construct a table mapping mpi_rank
- *		to the index of the first entry in the candidate list to
- *		be written by the process of that mpi_rank, and then use
- *		the table to control which entries are written and which
- *		are marked as clean as a function of the mpi_rank.
- *
- *		Note that the table must be identical on all processes, as
- *		all see the same candidate list, mpi_size, and mpi_rank --
- *		the inputs used to construct the table.  
- *
- *		We construct the table as follows.  Let:
- *
- *			n = num_candidates / mpi_size;
- *
- *			m = num_candidates % mpi_size;
- *
- *		Now allocate an array of integers of length mpi_size + 1, 
- *		and call this array candidate_assignment_table. 
- *
- *		Conceptually, if the number of candidates is a multiple
- *		of the mpi_size, we simply pass through the candidate list
- *		and assign n entries to each process to flush, with the 
- *		index of the first entry to flush in the location in 
- *		the candidate_assignment_table indicated by the mpi_rank
- *		of the process.  
- *
- *		In the more common case in which the candidate list isn't 
- *		isn't a multiple of the mpi_size, we pretend it is, and 
- *		give num_candidates % mpi_size processes one extra entry
- *		each to make things work out.
- *
- *		Once the table is constructed, we determine the first and
- *		last entry this process is to flush as follows:
- *
- *	 	first_entry_to_flush = candidate_assignment_table[mpi_rank]
- *
- *		last_entry_to_flush = 
- *			candidate_assignment_table[mpi_rank + 1] - 1;
- *		
- *		With these values determined, we simply scan through the 
- *		candidate list, marking all entries in the range 
- *		[first_entry_to_flush, last_entry_to_flush] for flush,
- *		and all others to be cleaned.
- *
- *		Finally, we scan the LRU from tail to head, flushing 
- *		or marking clean the candidate entries as indicated.
- *		If necessary, we scan the pinned list as well.
- *
- *		Note that this function will fail if any protected or 
- *		clean entries appear on the candidate list.
- *
- *		This function is used in managing sync points, and 
- *		shouldn't be used elsewhere.
- *
- * Return:      Success:        SUCCEED
- *
- *              Failure:        FAIL
- *
- * Programmer:  John Mainzer
- *              3/17/10
- *
- *-------------------------------------------------------------------------
- */
-#ifdef H5_HAVE_PARALLEL
-#define H5C_APPLY_CANDIDATE_LIST__DEBUG 0
-herr_t
-H5C_apply_candidate_list(H5F_t * f,
-                         hid_t primary_dxpl_id,
-                         hid_t secondary_dxpl_id,
-                         H5C_t * cache_ptr,
-                         int num_candidates,
-                         haddr_t * candidates_list_ptr,
-                         int mpi_rank,
-                         int mpi_size)
-{
-    hbool_t             first_flush = FALSE;
-    int                 i;
-    int			m;
-    int			n;
-    int			first_entry_to_flush;
-    int			last_entry_to_flush;
-    int			entries_to_clear = 0;
-    int			entries_to_flush = 0;
-    int			entries_to_flush_or_clear_last = 0;
-    int			entries_to_flush_collectively = 0;
-    int			entries_cleared = 0;
-    int			entries_flushed = 0;
-    int			entries_delayed = 0;
-    int			entries_flushed_or_cleared_last = 0;
-    int			entries_flushed_collectively = 0;
-    int			entries_examined = 0;
-    int			initial_list_len;
-    int               * candidate_assignment_table = NULL;
-    haddr_t		addr;
-    H5C_cache_entry_t *	clear_ptr = NULL;
-    H5C_cache_entry_t *	entry_ptr = NULL;
-    H5C_cache_entry_t *	flush_ptr = NULL;
-    H5C_cache_entry_t * delayed_ptr = NULL;
-#if H5C_DO_SANITY_CHECKS
-    haddr_t		last_addr;
-#endif /* H5C_DO_SANITY_CHECKS */
-#if H5C_APPLY_CANDIDATE_LIST__DEBUG
-    char		tbl_buf[1024];
-#endif /* H5C_APPLY_CANDIDATE_LIST__DEBUG */
-    herr_t              ret_value = SUCCEED;      /* Return value */
-
-    FUNC_ENTER_NOAPI(FAIL)
-
-    HDassert( cache_ptr != NULL );
-    HDassert( cache_ptr->magic == H5C__H5C_T_MAGIC );
-    HDassert( num_candidates > 0 );
-    HDassert( num_candidates <= cache_ptr->slist_len );
-    HDassert( candidates_list_ptr != NULL );
-    HDassert( 0 <= mpi_rank );
-    HDassert( mpi_rank < mpi_size );
-
-#if H5C_APPLY_CANDIDATE_LIST__DEBUG
-    HDfprintf(stdout, "%s:%d: setting up candidate assignment table.\n", 
-              FUNC, mpi_rank);
-    for ( i = 0; i < 1024; i++ ) tbl_buf[i] = '\0';
-    sprintf(&(tbl_buf[0]), "candidate list = ");
-    for ( i = 0; i < num_candidates; i++ )
-    {
-        sprintf(&(tbl_buf[HDstrlen(tbl_buf)]), " 0x%llx", 
-                (long long)(*(candidates_list_ptr + i)));
-    }
-    sprintf(&(tbl_buf[HDstrlen(tbl_buf)]), "\n");
-    HDfprintf(stdout, "%s", tbl_buf);
-#endif /* H5C_APPLY_CANDIDATE_LIST__DEBUG */
-
-    n = num_candidates / mpi_size;
-    m = num_candidates % mpi_size;
-    HDassert(n >= 0);
-
-    if(NULL == (candidate_assignment_table = (int *)H5MM_malloc(sizeof(int) * (size_t)(mpi_size + 1))))
-        HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed for candidate assignment table")
-
-    candidate_assignment_table[0] = 0;
-    candidate_assignment_table[mpi_size] = num_candidates;
-
-    if(m == 0) { /* mpi_size is an even divisor of num_candidates */
-        HDassert(n > 0);
-        for(i = 1; i < mpi_size; i++)
-            candidate_assignment_table[i] = candidate_assignment_table[i - 1] + n;
-    } /* end if */
-    else { 
-        for(i = 1; i <= m; i++)
-            candidate_assignment_table[i] = candidate_assignment_table[i - 1] + n + 1;
-
-        if(num_candidates < mpi_size) {
-            for(i = m + 1; i < mpi_size; i++)
-                candidate_assignment_table[i] = num_candidates;
-        } /* end if */
-        else {
-            for(i = m + 1; i < mpi_size; i++)
-                candidate_assignment_table[i] = candidate_assignment_table[i - 1] + n;
-        } /* end else */
-    } /* end else */
-    HDassert((candidate_assignment_table[mpi_size - 1] + n) == num_candidates);
-
-#if H5C_DO_SANITY_CHECKS
-    /* verify that the candidate assignment table has the expected form */
-    for ( i = 1; i < mpi_size - 1; i++ ) 
-    {
-        int a, b;
-
-        a = candidate_assignment_table[i] - candidate_assignment_table[i - 1];
-        b = candidate_assignment_table[i + 1] - candidate_assignment_table[i];
-
-        HDassert( n + 1 >= a );
-        HDassert( a >= b );
-        HDassert( b >= n );
-    }
-#endif /* H5C_DO_SANITY_CHECKS */
-
-    first_entry_to_flush = candidate_assignment_table[mpi_rank];
-    last_entry_to_flush = candidate_assignment_table[mpi_rank + 1] - 1;
-
-#if H5C_APPLY_CANDIDATE_LIST__DEBUG
-    for ( i = 0; i < 1024; i++ )
-        tbl_buf[i] = '\0';
-    sprintf(&(tbl_buf[0]), "candidate assignment table = ");
-    for(i = 0; i <= mpi_size; i++)
-        sprintf(&(tbl_buf[HDstrlen(tbl_buf)]), " %d", candidate_assignment_table[i]);
-    sprintf(&(tbl_buf[HDstrlen(tbl_buf)]), "\n");
-    HDfprintf(stdout, "%s", tbl_buf);
-
-    HDfprintf(stdout, "%s:%d: flush entries [%d, %d].\n", 
-              FUNC, mpi_rank, first_entry_to_flush, last_entry_to_flush);
-
-    HDfprintf(stdout, "%s:%d: marking entries.\n", FUNC, mpi_rank);
-#endif /* H5C_APPLY_CANDIDATE_LIST__DEBUG */
-
-    for(i = 0; i < num_candidates; i++) {
-        addr = candidates_list_ptr[i];
-        HDassert( H5F_addr_defined(addr) );
-
-#if H5C_DO_SANITY_CHECKS
-        if ( i > 0 ) {
-            if ( last_addr == addr ) {
-                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Duplicate entry in cleaned list.\n")
-            } else if ( last_addr > addr ) {
-                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "candidate list not sorted.\n")
-            }
-        }
-
-        last_addr = addr;
-#endif /* H5C_DO_SANITY_CHECKS */
-
-        H5C__SEARCH_INDEX(cache_ptr, addr, entry_ptr, FAIL)
-        if(entry_ptr == NULL) {
-            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Listed candidate entry not in cache?!?!?.")
-        } else if(!entry_ptr->is_dirty) {
-            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Listed entry not dirty?!?!?.")
-        } else if ( entry_ptr->is_protected ) {
-            /* For now at least, we can't deal with protected entries.
-             * If we encounter one, scream and die.  If it becomes an
-             * issue, we should be able to work around this. 
-             */
-            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Listed entry is protected?!?!?.")
-        } else {
-            /* determine whether the entry is to be cleared or flushed,
-             * and mark it accordingly.  We will scan the protected and 
-             * pinned list shortly, and clear or flush according to these
-             * markings.  
-             */
-            if((i >= first_entry_to_flush) && (i <= last_entry_to_flush)) {
-                entries_to_flush++;
-                entry_ptr->flush_immediately = TRUE;
-            } /* end if */
-            else {
-                entries_to_clear++;
-                entry_ptr->clear_on_unprotect = TRUE;
-            } /* end else */
-        } /* end else */
-    } /* end for */
-
-#if H5C_APPLY_CANDIDATE_LIST__DEBUG
-    HDfprintf(stdout, "%s:%d: num candidates/to clear/to flush = %d/%d/%d.\n", 
-              FUNC, mpi_rank, (int)num_candidates, (int)entries_to_clear,
-              (int)entries_to_flush);
-#endif /* H5C_APPLY_CANDIDATE_LIST__DEBUG */
-
-
-    /* We have now marked all the entries on the candidate list for 
-     * either flush or clear -- now scan the LRU and the pinned list
-     * for these entries and do the deed.
-     *
-     * Note that we are doing things in this round about manner so as
-     * to preserve the order of the LRU list to the best of our ability.
-     * If we don't do this, my experiments indicate that we will have a
-     * noticably poorer hit ratio as a result.
-     */
-
-#if H5C_APPLY_CANDIDATE_LIST__DEBUG
-    HDfprintf(stdout, "%s:%d: scanning LRU list. len = %d.\n", FUNC, mpi_rank,
-              (int)(cache_ptr->LRU_list_len));
-#endif /* H5C_APPLY_CANDIDATE_LIST__DEBUG */
-
-    /* ===================================================================== *
-     * Now scan the LRU and PEL lists, flushing or clearing entries as
-     * needed.
-     *
-     * The flush_me_last and flush_me_collectively flags may dictate how or
-     * when some entries can be flushed, and should be addressed here.
-     * However, in their initial implementation, these flags only apply to the
-     * superblock, so there's only a relatively small change to this function
-     * to account for this one case where they come into play. If these flags
-     * are ever expanded upon, this function and the following flushing steps
-     * should be reworked to account for additional cases.
-     * ===================================================================== */
-
-    entries_examined = 0;
-    initial_list_len = cache_ptr->LRU_list_len;
-    entry_ptr = cache_ptr->LRU_tail_ptr;
-
-    /* Examine each entry in the LRU list */
-    while((entry_ptr != NULL) && (entries_examined <= initial_list_len) &&
-            ((entries_cleared + entries_flushed) < num_candidates)) {
-
-        /* If this process needs to clear this entry. */
-        if(entry_ptr->clear_on_unprotect) {
-            entry_ptr->clear_on_unprotect = FALSE;
-            clear_ptr = entry_ptr;
-            entry_ptr = entry_ptr->prev;
-            entries_cleared++;
-
-#if ( H5C_APPLY_CANDIDATE_LIST__DEBUG > 1 )
-    HDfprintf(stdout, "%s:%d: clearing 0x%llx.\n", FUNC, mpi_rank,
-              (long long)clear_ptr->addr);
-#endif /* H5C_APPLY_CANDIDATE_LIST__DEBUG */
-
-            if(H5C_flush_single_entry(f,
-                                      primary_dxpl_id,
-                                      secondary_dxpl_id,
-                                      clear_ptr->type,
-                                      clear_ptr->addr,
-                                      H5C__FLUSH_CLEAR_ONLY_FLAG,
-                                      &first_flush,
-                                      TRUE) < 0)
-                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't clear entry.")
-        } /* end if */
-
-        /* Else, if this process needs to flush this entry. */
-        else if (entry_ptr->flush_immediately) {
-
-            entry_ptr->flush_immediately = FALSE;
-            flush_ptr = entry_ptr;
-            entry_ptr = entry_ptr->prev;
-            entries_flushed++;
-
-#if ( H5C_APPLY_CANDIDATE_LIST__DEBUG > 1 )
-    HDfprintf(stdout, "%s:%d: flushing 0x%llx.\n", FUNC, mpi_rank,
-              (long long)flush_ptr->addr);
-#endif /* H5C_APPLY_CANDIDATE_LIST__DEBUG */
-
-            if(H5C_flush_single_entry(f,
-                                      primary_dxpl_id,
-                                      secondary_dxpl_id,
-                                      flush_ptr->type,
-                                      flush_ptr->addr,
-                                      H5C__NO_FLAGS_SET,
-                                      &first_flush,
-                                      TRUE) < 0)
-                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't flush entry.")
-        } /* end else-if */
-
-        /* Otherwise, no action to be taken on this entry. Grab the next. */
-        else {
-            entry_ptr = entry_ptr->prev;
-        } /* end else */
-
-        entries_examined++;
-    } /* end while */
-
-#if H5C_APPLY_CANDIDATE_LIST__DEBUG
-    HDfprintf(stdout, "%s:%d: entries examined/cleared/flushed = %d/%d/%d.\n",
-              FUNC, mpi_rank, entries_examined,
-              entries_cleared, entries_flushed);
-#endif /* H5C_APPLY_CANDIDATE_LIST__DEBUG */
-
-    /* It is also possible that some of the cleared entries are on the
-     * pinned list.  Must scan that also.
-     */
-
-#if H5C_APPLY_CANDIDATE_LIST__DEBUG
-    HDfprintf(stdout, "%s:%d: scanning pinned entry list. len = %d\n",
-             FUNC, mpi_rank, (int)(cache_ptr->pel_len));
-#endif /* H5C_APPLY_CANDIDATE_LIST__DEBUG */
-
-    entry_ptr = cache_ptr->pel_head_ptr;
-    while((entry_ptr != NULL) &&
-          ((entries_cleared + entries_flushed + entries_delayed)
-            < num_candidates)) {
-
-        /* If entry is marked for flush or for clear */
-        if((entry_ptr->clear_on_unprotect||entry_ptr->flush_immediately)) {
-
-            /* If this entry needs to be flushed last */
-            if (entry_ptr->flush_me_last) {
-
-                /* At this time, only the superblock supports being
-                   flushed last. Conveniently, it also happens to be the only
-                   entry that supports being flushed collectively, as well. Also
-                   conveniently, it's always pinned, so we only need to check
-                   for it while scanning the PEL here. Finally, it's never
-                   included in a candidate list that excludes other dirty
-                   entries in a cache, so we can handle this relatively simple
-                   case here.
-                   
-                   For now, this function asserts this and saves the entry
-                   to flush it after scanning the rest of the PEL list.
-
-                   If there are ever more entries that either need to be
-                   flushed last and/or flushed collectively, this whole routine
-                   will need to be reworked to handle all additional cases. As
-                   it is the simple case of a single pinned entry needing
-                   flushed last and collectively is just a minor addition to
-                   this routine, but signficantly buffing up the usage of
-                   flush_me_last or flush_me_collectively will require a more
-                   intense rework of this function and potentially the function
-                   of candidate lists as a whole. */
-
-                HDassert(entry_ptr->flush_me_collectively);
-                entries_to_flush_or_clear_last++;
-                entries_to_flush_collectively++;
-                HDassert(entries_to_flush_or_clear_last == 1);
-                HDassert(entries_to_flush_collectively == 1);
-
-                /* Delay the entry. It will be flushed later. */
-                delayed_ptr = entry_ptr;
-                entries_delayed++;
-                HDassert(entries_delayed == 1);
-
-            } /* end if */
-
-            /* Else, this process needs to clear this entry. */
-            else if (entry_ptr->clear_on_unprotect) {
-                HDassert(!entry_ptr->flush_immediately);
-                entry_ptr->clear_on_unprotect = FALSE;
-                clear_ptr = entry_ptr;
-                entry_ptr = entry_ptr->next;
-                entries_cleared++;
-
-#if ( H5C_APPLY_CANDIDATE_LIST__DEBUG > 1 )
-            HDfprintf(stdout, "%s:%d: clearing 0x%llx.\n", FUNC, mpi_rank,
-                      (long long)clear_ptr->addr);
-#endif /* H5C_APPLY_CANDIDATE_LIST__DEBUG */
-
-                if(H5C_flush_single_entry(f,
-                                          primary_dxpl_id,
-                                          secondary_dxpl_id,
-                                          clear_ptr->type,
-                                          clear_ptr->addr,
-                                          H5C__FLUSH_CLEAR_ONLY_FLAG,
-                                          &first_flush,
-                                          TRUE) < 0)
-                    HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't clear entry.")
-            } /* end else-if */
-
-            /* Else, if this process needs to independently flush this entry. */
-            else if (entry_ptr->flush_immediately) {
-                entry_ptr->flush_immediately = FALSE;
-                flush_ptr = entry_ptr;
-                entry_ptr = entry_ptr->next;
-                entries_flushed++;
-
-#if ( H5C_APPLY_CANDIDATE_LIST__DEBUG > 1 )
-                HDfprintf(stdout, "%s:%d: flushing 0x%llx.\n", FUNC, mpi_rank,
-                      (long long)flush_ptr->addr);
-#endif /* H5C_APPLY_CANDIDATE_LIST__DEBUG */
-
-                if(H5C_flush_single_entry(f,
-                                          primary_dxpl_id,
-                                          secondary_dxpl_id,
-                                          flush_ptr->type,
-                                          flush_ptr->addr,
-                                          H5C__NO_FLAGS_SET,
-                                          &first_flush,
-                                          TRUE) < 0)
-                    HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't flush entry.")
-            } /* end else-if */
-        } /* end if */
-
-        /* Otherwise, this entry is not marked for flush or clear. Grab the next. */
-        else {
-            entry_ptr = entry_ptr->next;
-        } /* end else */
-
-    } /* end while */
-
-#if H5C_APPLY_CANDIDATE_LIST__DEBUG
-    HDfprintf(stdout,
-              "%s:%d: pel entries examined/cleared/flushed = %d/%d/%d.\n",
-              FUNC, mpi_rank, entries_examined,
-              entries_cleared, entries_flushed);
-    HDfprintf(stdout, "%s:%d: done.\n", FUNC, mpi_rank);
-
-    HDfsync(stdout);
-#endif /* H5C_APPLY_CANDIDATE_LIST__DEBUG */
-
-    /* ====================================================================== *
-     * Now, handle all delayed entries.                                       *
-     *                                                                        *
-     * This can *only* be the superblock at this time, so it's relatively     *
-     * easy to deal with. We're collectively flushing the entry saved from    *
-     * above. This will need to be handled differently if there are ever more *
-     * than one entry needing this special treatment.)                        *
-     * ====================================================================== */
-
-    if (delayed_ptr) {
-
-        if (delayed_ptr->clear_on_unprotect) {
-            entry_ptr->clear_on_unprotect = FALSE;
-            entries_cleared++;
-        } else if (delayed_ptr->flush_immediately) {
-            entry_ptr->flush_immediately = FALSE;
-            entries_flushed++;
-        } /* end if */
-
-        if(H5C_flush_single_entry(f,
-                                  primary_dxpl_id,
-                                  secondary_dxpl_id,
-                                  delayed_ptr->type,
-                                  delayed_ptr->addr,
-                                  H5C__NO_FLAGS_SET,
-                                  &first_flush,
-                                  TRUE) < 0)
-            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL,
-                        "Can't flush entry collectively.")
-
-        entries_flushed_collectively++;
-        entries_flushed_or_cleared_last++;
-    } /* end if */
-
-    /* ====================================================================== *
-     * Finished flushing everything.                                          *
-     * ====================================================================== */
-
-    HDassert((entries_flushed == entries_to_flush));
-    HDassert((entries_cleared == entries_to_clear));
-    HDassert((entries_flushed_or_cleared_last == entries_to_flush_or_clear_last));
-    HDassert((entries_flushed_collectively == entries_to_flush_collectively));
-    
-    if((entries_flushed != entries_to_flush) || 
-       (entries_cleared != entries_to_clear) ||
-       (entries_flushed_or_cleared_last != entries_to_flush_or_clear_last) ||
-       (entries_flushed_collectively != entries_to_flush_collectively))
-        HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "entry count mismatch.")
-
-done:
-    if(candidate_assignment_table != NULL)
-        candidate_assignment_table = (int *)H5MM_xfree((void *)candidate_assignment_table);
-
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* H5C_apply_candidate_list() */
-#endif /* H5_HAVE_PARALLEL */
-
-
-/*-------------------------------------------------------------------------
- * Function:    H5C_construct_candidate_list__clean_cache
- *
- * Purpose:     Construct the list of entries that should be flushed to 
- *		clean all entries in the cache.
- *
- *		This function is used in managing sync points, and 
- *		shouldn't be used elsewhere.
- *
- * Return:      Success:        SUCCEED
- *
- *              Failure:        FAIL
- *
- * Programmer:  John Mainzer
- *              3/17/10
- *
- *-------------------------------------------------------------------------
- */
-#ifdef H5_HAVE_PARALLEL
-herr_t
-H5C_construct_candidate_list__clean_cache(H5C_t * cache_ptr)
+static herr_t 
+H5C__epoch_marker_clear(const H5F_t H5_ATTR_UNUSED *f, void H5_ATTR_UNUSED * thing, hbool_t H5_ATTR_UNUSED about_to_destroy)
 {
-    size_t              space_needed;
-    herr_t              ret_value = SUCCEED;      /* Return value */
+    FUNC_ENTER_STATIC_NOERR /* Yes, even though this pushes an error on the stack */
 
-    FUNC_ENTER_NOAPI(FAIL)
+    HERROR(H5E_CACHE, H5E_SYSTEM, "called unreachable fcn.");
 
-    HDassert( cache_ptr != NULL );
-    HDassert( cache_ptr->magic == H5C__H5C_T_MAGIC );
-
-    /* As a sanity check, set space needed to the size of the skip list.
-     * This should be the sum total of the sizes of all the dirty entries
-     * in the metadata cache.
-     */
-    space_needed = cache_ptr->slist_size;
-
-    /* Recall that while we shouldn't have any protected entries at this
-     * point, it is possible that some dirty entries may reside on the
-     * pinned list at this point.
-     */
-    HDassert( cache_ptr->slist_size <= 
-              (cache_ptr->dLRU_list_size + cache_ptr->pel_size) );
-    HDassert( cache_ptr->slist_len  <= 
-              (cache_ptr->dLRU_list_len + cache_ptr->pel_len) );
-
-    if(space_needed > 0) { /* we have work to do */
-        H5C_cache_entry_t *entry_ptr;
-        int     nominated_entries_count = 0;
-        size_t  nominated_entries_size = 0;
-        haddr_t	nominated_addr;
-
-        HDassert( cache_ptr->slist_len > 0 );
-
-        /* Scan the dirty LRU list from tail forward and nominate sufficient
-         * entries to free up the necessary space. 
-         */
-        entry_ptr = cache_ptr->dLRU_tail_ptr;
-        while((nominated_entries_size < space_needed) &&
-                (nominated_entries_count < cache_ptr->slist_len) &&
-                (entry_ptr != NULL)) {
-            HDassert( ! (entry_ptr->is_protected) );
-            HDassert( ! (entry_ptr->is_read_only) );
-            HDassert( entry_ptr->ro_ref_count == 0 );
-            HDassert( entry_ptr->is_dirty );
-            HDassert( entry_ptr->in_slist );
-
-            nominated_addr = entry_ptr->addr;
-            if(H5AC_add_candidate((H5AC_t *)cache_ptr, nominated_addr) < 0)
-                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "H5AC_add_candidate() failed(1).")
-
-            nominated_entries_size += entry_ptr->size;
-            nominated_entries_count++;
-            entry_ptr = entry_ptr->aux_prev;
-        } /* end while */
-        HDassert( entry_ptr == NULL );
-
-        /* it is possible that there are some dirty entries on the 
-         * protected entry list as well -- scan it too if necessary
-         */
-        entry_ptr = cache_ptr->pel_head_ptr;
-        while((nominated_entries_size < space_needed) &&
-                (nominated_entries_count < cache_ptr->slist_len) &&
-                (entry_ptr != NULL)) {
-            if(entry_ptr->is_dirty) {
-                HDassert( ! (entry_ptr->is_protected) );
-                HDassert( ! (entry_ptr->is_read_only) );
-                HDassert( entry_ptr->ro_ref_count == 0 );
-                HDassert( entry_ptr->is_dirty );
-                HDassert( entry_ptr->in_slist );
-
-                nominated_addr = entry_ptr->addr;
-                if(H5AC_add_candidate((H5AC_t *)cache_ptr, nominated_addr) < 0)
-                    HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "H5AC_add_candidate() failed(2).")
-
-                nominated_entries_size += entry_ptr->size;
-                nominated_entries_count++;
-            } /* end if */
-
-            entry_ptr = entry_ptr->next;
-        } /* end while */
-
-        HDassert( nominated_entries_count == cache_ptr->slist_len );
-        HDassert( nominated_entries_size == space_needed );
-    } /* end if */
-
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* H5C_construct_candidate_list__clean_cache() */
-#endif /* H5_HAVE_PARALLEL */
+    FUNC_LEAVE_NOAPI(FAIL)
+} /* end H5C__epoch_marker_clear() */
 
 
-/*-------------------------------------------------------------------------
- * Function:    H5C_construct_candidate_list__min_clean
- *
- * Purpose:     Construct the list of entries that should be flushed to 
- *		get the cache back within its min clean constraints.
- *
- *		This function is used in managing sync points, and 
- *		shouldn't be used elsewhere.
- *
- * Return:      Success:        SUCCEED
- *
- *              Failure:        FAIL
- *
- * Programmer:  John Mainzer
- *              3/17/10
- *
- *-------------------------------------------------------------------------
- */
-#ifdef H5_HAVE_PARALLEL
-herr_t
-H5C_construct_candidate_list__min_clean(H5C_t * cache_ptr)
+static herr_t 
+H5C__epoch_marker_fsf_size(const void H5_ATTR_UNUSED * thing, size_t H5_ATTR_UNUSED *fsf_size_ptr)
 {
-    size_t              space_needed = 0;
-    herr_t              ret_value = SUCCEED;      /* Return value */
+    FUNC_ENTER_STATIC_NOERR /* Yes, even though this pushes an error on the stack */
 
-    FUNC_ENTER_NOAPI(FAIL)
+    HERROR(H5E_CACHE, H5E_SYSTEM, "called unreachable fcn.");
 
-    HDassert( cache_ptr != NULL );
-    HDassert( cache_ptr->magic == H5C__H5C_T_MAGIC );
+    FUNC_LEAVE_NOAPI(FAIL)
+} /* end H5C__epoch_marker_fsf_size() */
 
-    /* compute the number of bytes (if any) that must be flushed to get the 
-     * cache back within its min clean constraints.
-     */
-    if(cache_ptr->max_cache_size > cache_ptr->index_size) {
-        if(((cache_ptr->max_cache_size - cache_ptr->index_size) +
-               cache_ptr->cLRU_list_size) >= cache_ptr->min_clean_size)
-            space_needed = 0;
-        else
-            space_needed = cache_ptr->min_clean_size -
-                ((cache_ptr->max_cache_size - cache_ptr->index_size) +
-                 cache_ptr->cLRU_list_size);
-    } /* end if */
-    else {
-        if(cache_ptr->min_clean_size <= cache_ptr->cLRU_list_size)
-           space_needed = 0;
-        else
-            space_needed = cache_ptr->min_clean_size -
-                           cache_ptr->cLRU_list_size;
-    } /* end else */
-
-    if(space_needed > 0) { /* we have work to do */
-        H5C_cache_entry_t *entry_ptr;
-        int    nominated_entries_count = 0;
-        size_t nominated_entries_size = 0;
-
-        HDassert( cache_ptr->slist_len > 0 );
-
-        /* Scan the dirty LRU list from tail forward and nominate sufficient
-         * entries to free up the necessary space. 
-         */
-        entry_ptr = cache_ptr->dLRU_tail_ptr;
-        while((nominated_entries_size < space_needed) &&
-                (nominated_entries_count < cache_ptr->slist_len) &&
-                (entry_ptr != NULL) &&
-                (!entry_ptr->flush_me_last)) {
-            haddr_t		nominated_addr;
-
-            HDassert( ! (entry_ptr->is_protected) );
-            HDassert( ! (entry_ptr->is_read_only) );
-            HDassert( entry_ptr->ro_ref_count == 0 );
-            HDassert( entry_ptr->is_dirty );
-            HDassert( entry_ptr->in_slist );
-
-            nominated_addr = entry_ptr->addr;
-            if(H5AC_add_candidate((H5AC_t *)cache_ptr, nominated_addr) < 0)
-                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "H5AC_add_candidate() failed.")
-
-            nominated_entries_size += entry_ptr->size;
-            nominated_entries_count++;
-            entry_ptr = entry_ptr->aux_prev;
-        } /* end while */
-        HDassert( nominated_entries_count <= cache_ptr->slist_len );
-        HDassert( nominated_entries_size >= space_needed );
-    } /* end if */
-
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* H5C_construct_candidate_list__min_clean() */
-#endif /* H5_HAVE_PARALLEL */
 
 
 /*-------------------------------------------------------------------------
@@ -1184,6 +499,9 @@ H5C_create(size_t		      max_cache_size,
     /* Tagging Field Initializations */
     cache_ptr->ignore_tags                      = FALSE;
 
+    cache_ptr->slist_changed			= FALSE;
+    cache_ptr->slist_change_in_pre_serialize	= FALSE;
+    cache_ptr->slist_change_in_serialize	= FALSE;
     cache_ptr->slist_len			= 0;
     cache_ptr->slist_size			= (size_t)0;
 
@@ -1197,6 +515,9 @@ H5C_create(size_t		      max_cache_size,
         (cache_ptr->index)[i] = NULL;
     }
 
+    cache_ptr->entries_removed_counter		= 0;
+    cache_ptr->last_entry_removed_ptr		= NULL;
+
     cache_ptr->pl_len				= 0;
     cache_ptr->pl_size				= (size_t)0;
     cache_ptr->pl_head_ptr			= NULL;
@@ -1271,11 +592,8 @@ H5C_create(size_t		      max_cache_size,
     /* Set non-zero/FALSE/NULL fields for epoch markers */
     for ( i = 0; i < H5C__MAX_EPOCH_MARKERS; i++ )
     {
-        (cache_ptr->epoch_marker_active)[i]		 = FALSE;
-#ifndef NDEBUG
         ((cache_ptr->epoch_markers)[i]).magic		 =
 					       H5C__H5C_CACHE_ENTRY_T_MAGIC;
-#endif /* NDEBUG */
         ((cache_ptr->epoch_markers)[i]).addr		 = (haddr_t)i;
         ((cache_ptr->epoch_markers)[i]).type		 = &epoch_marker_class;
     }
@@ -1530,9 +848,7 @@ H5C_def_auto_resize_rpt_fcn(H5C_t * cache_ptr,
  *-------------------------------------------------------------------------
  */
 herr_t
-H5C_dest(H5F_t * f,
-         hid_t	 primary_dxpl_id,
-         hid_t	 secondary_dxpl_id)
+H5C_dest(H5F_t * f, hid_t dxpl_id)
 {
     H5C_t * cache_ptr = f->shared->cache;
     herr_t ret_value = SUCCEED;      /* Return value */
@@ -1544,8 +860,7 @@ H5C_dest(H5F_t * f,
     HDassert(cache_ptr->magic == H5C__H5C_T_MAGIC);
 
     /* Flush and invalidate all cache entries */
-    if(H5C_flush_invalidate_cache(f, primary_dxpl_id, secondary_dxpl_id,
-                H5C__NO_FLAGS_SET) < 0 )
+    if(H5C_flush_invalidate_cache(f, dxpl_id, H5C__NO_FLAGS_SET) < 0 )
         HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "unable to flush cache")
 
     if(cache_ptr->slist_ptr != NULL) {
@@ -1570,7 +885,9 @@ H5C_dest(H5F_t * f,
 #endif /* H5C_DO_SANITY_CHECKS */
 #endif /* NDEBUG */
 
+#ifndef NDEBUG
     cache_ptr->magic = 0;
+#endif /* NDEBUG */
 
     cache_ptr = H5FL_FREE(H5C_t, cache_ptr);
 
@@ -1595,17 +912,16 @@ done:
  *-------------------------------------------------------------------------
  */
 herr_t
-H5C_expunge_entry(H5F_t *             f,
-                  hid_t               primary_dxpl_id,
-                  hid_t               secondary_dxpl_id,
-                  const H5C_class_t * type,
-                  haddr_t 	      addr,
-                  unsigned 	      flags)
+H5C_expunge_entry(H5F_t *f, hid_t dxpl_id, const H5C_class_t *type,
+    haddr_t addr, unsigned flags)
 {
     H5C_t *		cache_ptr;
-    herr_t		result;
-    hbool_t		first_flush = TRUE;
     H5C_cache_entry_t *	entry_ptr = NULL;
+    unsigned            flush_flags = (H5C__FLUSH_INVALIDATE_FLAG | H5C__FLUSH_CLEAR_ONLY_FLAG);
+#if H5C_DO_SANITY_CHECKS
+    hbool_t entry_was_dirty;
+    hsize_t entry_size;
+#endif /* H5C_DO_SANITY_CHECKS */
     herr_t		ret_value = SUCCEED;      /* Return value */
 
     FUNC_ENTER_NOAPI(FAIL)
@@ -1616,8 +932,6 @@ H5C_expunge_entry(H5F_t *             f,
     HDassert(cache_ptr);
     HDassert(cache_ptr->magic == H5C__H5C_T_MAGIC);
     HDassert(type);
-    HDassert(type->clear);
-    HDassert(type->dest);
     HDassert(H5F_addr_defined(addr));
 
 #if H5C_DO_EXTREME_SANITY_CHECKS
@@ -1641,27 +955,37 @@ H5C_expunge_entry(H5F_t *             f,
     if(entry_ptr->is_pinned)
         HGOTO_ERROR(H5E_CACHE, H5E_CANTEXPUNGE, FAIL, "Target entry is pinned.")
 
-    /* Pass along 'free file space' flag to cache client */
-    entry_ptr->free_file_space_on_destroy = ( (flags & H5C__FREE_FILE_SPACE_FLAG) != 0 );
-
-    /* If we get this far, call H5C_flush_single_entry() with the
+    /* If we get this far, call H5C__flush_single_entry() with the
      * H5C__FLUSH_INVALIDATE_FLAG and the H5C__FLUSH_CLEAR_ONLY_FLAG.
      * This will clear the entry, and then delete it from the cache.
      */
-    result = H5C_flush_single_entry(f,
-                                    primary_dxpl_id,
-                                    secondary_dxpl_id,
-                                    entry_ptr->type,
-                                    entry_ptr->addr,
-                                    H5C__FLUSH_INVALIDATE_FLAG | H5C__FLUSH_CLEAR_ONLY_FLAG,
-                                    &first_flush,
-                                    TRUE);
 
-    if ( result < 0 ) {
+    /* Pass along 'free file space' flag to  cache client.  */
+    flush_flags |= (flags & H5C__FREE_FILE_SPACE_FLAG);
+
+#if H5C_DO_SANITY_CHECKS
+    entry_was_dirty = entry_ptr->is_dirty;
+    entry_size      = entry_ptr->size;
+#endif /* H5C_DO_EXTREME_SANITY_CHECKS */
+    
+    /* Delete the entry from the skip list on destroy */
+    flush_flags |= H5C__DEL_FROM_SLIST_ON_DESTROY_FLAG;
+
+    if(H5C__flush_single_entry(f, dxpl_id, entry_ptr, flush_flags, NULL) < 0)
+        HGOTO_ERROR(H5E_CACHE, H5E_CANTEXPUNGE, FAIL, "can't flush entry")
 
-        HGOTO_ERROR(H5E_CACHE, H5E_CANTEXPUNGE, FAIL, \
-                    "H5C_flush_single_entry() failed.")
+#if H5C_DO_SANITY_CHECKS
+    if ( entry_was_dirty )
+    {
+        /* we have just removed an entry from the skip list.  Thus 
+         * we must touch up cache_ptr->slist_len_increase and
+         * cache_ptr->slist_size_increase to keep from skewing
+         * the sanity checks on flushes.
+         */
+        cache_ptr->slist_len_increase -= 1;
+        cache_ptr->slist_size_increase -= (int64_t)(entry_size);
     }
+#endif /* H5C_DO_SANITY_CHECKS */
 
 done:
 #if H5C_DO_EXTREME_SANITY_CHECKS
@@ -1698,20 +1022,33 @@ done:
  * Programmer:  John Mainzer
  *		6/2/04
  *
+ * Changes:	Modified function to test for slist chamges in 
+ *		pre_serialize and serialize callbacks, and re-start
+ *		scans through the slist when such changes occur.
+ *
+ *		This has been a potential problem for some time,
+ *		and there has been code in this function to deal 
+ *		with elements of this issue.  However the shift 
+ *		to the V3 cache in combination with the activities
+ *		of some of the cache clients (in particular the 
+ *		free space manager and the fractal heap) have
+ *		made this re-work necessary.
+ *
+ *						JRM -- 12/13/14
+ *
  *-------------------------------------------------------------------------
  */
 herr_t
-H5C_flush_cache(H5F_t *f, hid_t primary_dxpl_id, hid_t secondary_dxpl_id, unsigned flags)
+H5C_flush_cache(H5F_t *f, hid_t dxpl_id, unsigned flags)
 {
     H5C_t * cache_ptr = f->shared->cache;
-    herr_t              status;
     herr_t		ret_value = SUCCEED;
     hbool_t             destroy;
     hbool_t		flushed_entries_last_pass;
     hbool_t		flush_marked_entries;
-    hbool_t		first_flush = TRUE;
     hbool_t		ignore_protected;
     hbool_t		tried_to_flush_protected_entry = FALSE;
+    hbool_t		restart_slist_scan;
     int32_t		passes = 0;
     int32_t		protected_entries = 0;
     H5SL_node_t * 	node_ptr = NULL;
@@ -1722,6 +1059,10 @@ H5C_flush_cache(H5F_t *f, hid_t primary_dxpl_id, hid_t secondary_dxpl_id, unsign
     int64_t		flushed_entries_size = 0;
     int64_t		initial_slist_len = 0;
     size_t              initial_slist_size = 0;
+    int64_t		entry_size_change;
+    int64_t	      * entry_size_change_ptr = &entry_size_change;
+#else /* H5C_DO_SANITY_CHECKS */
+    int64_t           * entry_size_change_ptr = NULL;
 #endif /* H5C_DO_SANITY_CHECKS */
 
     FUNC_ENTER_NOAPI(FAIL)
@@ -1757,20 +1098,8 @@ H5C_flush_cache(H5F_t *f, hid_t primary_dxpl_id, hid_t secondary_dxpl_id, unsign
     cache_ptr->flush_in_progress = TRUE;
 
     if ( destroy ) {
-
-        status = H5C_flush_invalidate_cache(f,
-			                    primary_dxpl_id,
-					    secondary_dxpl_id,
-					    flags);
-
-        if ( status < 0 ) {
-
-            /* This shouldn't happen -- if it does, we are toast so
-             * just scream and die.
-             */
-            HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, \
-			"flush invalidate failed.")
-        }
+        if(H5C_flush_invalidate_cache(f, dxpl_id, flags) < 0)
+            HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "flush invalidate failed.")
     } else {
 	/* When we are only flushing marked entries, the slist will usually
 	 * still contain entries when we have flushed everything we should.
@@ -1780,6 +1109,18 @@ H5C_flush_cache(H5F_t *f, hid_t primary_dxpl_id, hid_t secondary_dxpl_id, unsign
 
 	flushed_entries_last_pass = TRUE;
 
+        /* set the cache_ptr->slist_change_in_pre_serialize and
+	 * cache_ptr->slist_change_in_serialize to false.
+         *
+         * These flags are set to TRUE by H5C__flush_single_entry if the 
+ 	 * slist is modified by a pre_serialize or serialize call respectively.
+         * H5C_flush_cache uses these flags to detect any modifications
+         * to the slist that might corrupt the scan of the slist -- and 
+	 * restart the scan in this event.
+         */
+        cache_ptr->slist_change_in_pre_serialize = FALSE;
+        cache_ptr->slist_change_in_serialize = FALSE;
+
         while ( ( passes < H5C__MAX_PASSES_ON_FLUSH ) &&
 		( cache_ptr->slist_len != 0 ) &&
 		( protected_entries == 0 ) &&
@@ -1797,18 +1138,6 @@ H5C_flush_cache(H5F_t *f, hid_t primary_dxpl_id, hid_t secondary_dxpl_id, unsign
             {
                 hbool_t flushed_during_dep_loop = FALSE;
 
-                /* Start at beginning of skip list each time */
-                node_ptr = H5SL_first(cache_ptr->slist_ptr);
-                HDassert( node_ptr != NULL );
-
-                /* Get cache entry for this node */
-                next_entry_ptr = (H5C_cache_entry_t *)H5SL_item(node_ptr);
-                if ( NULL == next_entry_ptr )
-                    HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "next_entry_ptr == NULL ?!?!")
-                HDassert( next_entry_ptr->magic == H5C__H5C_CACHE_ENTRY_T_MAGIC );
-                HDassert( next_entry_ptr->is_dirty );
-                HDassert( next_entry_ptr->in_slist );
-
 #if H5C_DO_SANITY_CHECKS
                 /* For sanity checking, try to verify that the skip list has
                  * the expected size and number of entries at the end of each
@@ -1818,8 +1147,10 @@ H5C_flush_cache(H5F_t *f, hid_t primary_dxpl_id, hid_t secondary_dxpl_id, unsign
                  * or may not flush all the entries in the slist.
                  *
                  * To make things more entertaining, with the advent of the
-                 * fractal heap, the entry flush callback can cause entries
-                 * to be dirtied, resized, and/or moved.
+                 * fractal heap, the entry serialize callback can cause entries
+                 * to be dirtied, resized, and/or moved.  Also, the 
+                 * pre_serialize callback can result in an entry being 
+                 * removed from the cache via the take ownership flag.
                  *
                  * To deal with this, we first make note of the initial
                  * skip list length and size:
@@ -1834,7 +1165,8 @@ H5C_flush_cache(H5F_t *f, hid_t primary_dxpl_id, hid_t secondary_dxpl_id, unsign
                 flushed_entries_size = 0;
 
                 /* As mentioned above, there is the possibility that
-                 * entries will be dirtied, resized, and/or flushed during
+                 * entries will be dirtied, resized, flushed, or removed
+                 * from the cache via the take ownership flag  during
                  * our pass through the skip list.  To capture the number
                  * of entries added, and the skip list size delta,
                  * zero the slist_len_increase and slist_size_increase of
@@ -1851,53 +1183,60 @@ H5C_flush_cache(H5F_t *f, hid_t primary_dxpl_id, hid_t secondary_dxpl_id, unsign
                  */
 #endif /* H5C_DO_SANITY_CHECKS */
 
-                while ( node_ptr != NULL )
+                restart_slist_scan = TRUE;
+
+                while ( ( restart_slist_scan ) || ( node_ptr != NULL ) )
                 {
-                    entry_ptr = next_entry_ptr;
+                    if ( restart_slist_scan )
+                    {
+                        restart_slist_scan = FALSE;
 
-                    /* With the advent of the fractal heap, it is possible
-                     * that the flush callback will dirty and/or resize
-                     * other entries in the cache.  In particular, while
-                     * Quincey has promised me that this will never happen,
-                     * it is possible that the flush callback for an
-                     * entry may protect an entry that is not in the cache,
-                     * perhaps causing the cache to flush and possibly
-                     * evict the entry associated with node_ptr to make
-                     * space for the new entry.
-                     *
-                     * Thus we do a bit of extra sanity checking on entry_ptr,
-                     * and break out of this scan of the skip list if we
-                     * detect minor problems.  We have a bit of leaway on the
-                     * number of passes though the skip list, so this shouldn't
-                     * be an issue in the flush in and of itself, as it should
-                     * be all but impossible for this to happen more than once
-                     * in any flush.
-                     *
-                     * Observe that that breaking out of the scan early
-                     * shouldn't break the sanity checks just after the end
-                     * of this while loop.
-                     *
-                     * If an entry has merely been marked clean and removed from
-                     * the s-list, we simply break out of the scan.
-                     *
-                     * If the entry has been evicted, we flag an error and
-                     * exit.
-                     */
-#ifndef NDEBUG
-                    if ( entry_ptr->magic != H5C__H5C_CACHE_ENTRY_T_MAGIC ) {
+                        /* Start at beginning of skip list */
+                        node_ptr = H5SL_first(cache_ptr->slist_ptr);
 
-                        HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "entry_ptr->magic is invalid ?!?!")
+                        if ( node_ptr == NULL )
+                        {
+                            /* the slist is empty -- break out of inner loop */
+			    break;
+                        }
+                        HDassert( node_ptr != NULL );
 
-                    } else
-#endif /* NDEBUG */
-                    if ( ( ! entry_ptr->is_dirty ) ||
-                         ( ! entry_ptr->in_slist ) ) {
+                        /* Get cache entry for this node */
+                        next_entry_ptr = 
+                            (H5C_cache_entry_t *)H5SL_item(node_ptr);
 
-                        /* the s-list has been modified out from under us.
-                         * break out of the loop.
-                         */
-                        goto end_of_inner_loop;;
+                        if(NULL == next_entry_ptr)
+                            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, \
+                                        "next_entry_ptr == NULL ?!?!")
+
+                        HDassert( next_entry_ptr->magic == \
+                                  H5C__H5C_CACHE_ENTRY_T_MAGIC );
+                        HDassert( next_entry_ptr->is_dirty );
+                        HDassert( next_entry_ptr->in_slist );
                     }
+                    
+                    entry_ptr = next_entry_ptr;
+
+                    /* With the advent of the fractal heap, the free space
+                     * manager, and the version 3 cache, it is possible
+                     * that the pre-serialize or serialize callback will 
+                     * dirty, resize, or take ownership of other entries 
+                     * in the cache.  
+                     *
+                     * To deal with this, I have inserted code to detect any
+                     * change in the skip list not directly under the control
+                     * of this function.  If such modifications are detected,
+                     * we must re-start the scan of the skip list to avoid 
+                     * the possibility that the target of the next_entry_ptr
+                     * may have been flushed or deleted from the cache.
+                     *
+                     * To verify that all such possibilities have been dealt
+                     * with, we do a bit of extra sanity checking on 
+                     * entry_ptr.
+                     */
+                    HDassert(entry_ptr->magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+                    HDassert(entry_ptr->in_slist);
+                    HDassert(entry_ptr->is_dirty);
 
                     /* increment node pointer now, before we delete its target
                      * from the slist.
@@ -1911,6 +1250,7 @@ H5C_flush_cache(H5F_t *f, hid_t primary_dxpl_id, hid_t secondary_dxpl_id, unsign
                         HDassert( next_entry_ptr->magic == H5C__H5C_CACHE_ENTRY_T_MAGIC );
                         HDassert( next_entry_ptr->is_dirty );
                         HDassert( next_entry_ptr->in_slist );
+                        HDassert( entry_ptr != next_entry_ptr );
                     } else {
                         next_entry_ptr = NULL;
 		    }
@@ -1927,9 +1267,9 @@ H5C_flush_cache(H5F_t *f, hid_t primary_dxpl_id, hid_t secondary_dxpl_id, unsign
 
                         if ( entry_ptr->is_protected ) {
 
-                            /* we probably have major problems -- but lets flush
-                             * everything we can before we decide whether to flag
-                             * an error.
+                            /* we probably have major problems -- but lets 
+                             * flush everything we can before we decide 
+                             * whether to flag an error.
                              */
                             tried_to_flush_protected_entry = TRUE;
                             protected_entries++;
@@ -1944,24 +1284,39 @@ H5C_flush_cache(H5F_t *f, hid_t primary_dxpl_id, hid_t secondary_dxpl_id, unsign
 #if H5C_DO_SANITY_CHECKS
                                 flushed_entries_count++;
                                 flushed_entries_size += (int64_t)entry_ptr->size;
+                                entry_size_change = 0;
 #endif /* H5C_DO_SANITY_CHECKS */
-                                status = H5C_flush_single_entry(f,
-                                                                primary_dxpl_id,
-                                                                secondary_dxpl_id,
-                                                                NULL,
-                                                                entry_ptr->addr,
-                                                                flags,
-                                                                &first_flush,
-                                                                FALSE);
-                                if ( status < 0 ) {
-
-                                    /* This shouldn't happen -- if it does, 
-                                     * we are toast so just scream and die.
-                                     */
-                                    HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, \
-                                                "dirty pinned entry flush failed.")
-                                } /* end if */
+                                if(H5C__flush_single_entry(f, dxpl_id, entry_ptr, flags, entry_size_change_ptr) < 0 )
+                                    HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "dirty pinned entry flush failed.")
+
+#if H5C_DO_SANITY_CHECKS
+                                /* it is possible that the entry size changed
+                                 * during flush -- update flushed_entries_size
+                                 * to account for this.
+                                 */
+                                flushed_entries_size += entry_size_change;
+#endif /* H5C_DO_SANITY_CHECKS */
+
                                 flushed_during_dep_loop = TRUE;
+
+                                if ((cache_ptr->slist_change_in_serialize) ||
+                                    (cache_ptr->slist_change_in_pre_serialize))
+                                {
+                                    /* The slist has been modified by something
+                                     * other than the simple removal of the 
+                                     * of the flushed entry after the flush.
+                                     * 
+                                     * This has the potential to corrupt the
+                                     * scan through the slist, so restart it.
+                                     */
+                                    restart_slist_scan = TRUE;
+                                    cache_ptr->slist_change_in_pre_serialize 
+                                        = FALSE;
+                                    cache_ptr->slist_change_in_serialize 
+                                        = FALSE;
+
+				    H5C__UPDATE_STATS_FOR_SLIST_SCAN_RESTART(cache_ptr)
+                                }
                             } /* end if */
                             else if(entry_ptr->flush_dep_height < curr_flush_dep_height)
                                 /* This shouldn't happen -- if it does, just scream and die.  */
@@ -1977,31 +1332,46 @@ H5C_flush_cache(H5F_t *f, hid_t primary_dxpl_id, hid_t secondary_dxpl_id, unsign
 #if H5C_DO_SANITY_CHECKS
                                 flushed_entries_count++;
                                 flushed_entries_size += (int64_t)entry_ptr->size;
+                                entry_size_change = 0;
+#endif /* H5C_DO_SANITY_CHECKS */
+                                if(H5C__flush_single_entry(f, dxpl_id, entry_ptr, flags, entry_size_change_ptr) < 0)
+                                    HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "Can't flush entry.")
+
+#if H5C_DO_SANITY_CHECKS
+                                /* it is possible that the entry size changed
+                                 * during flush -- update flushed_entries_size
+                                 * to account for this.
+                                 */
+                                flushed_entries_size += entry_size_change;
 #endif /* H5C_DO_SANITY_CHECKS */
-                                status = H5C_flush_single_entry(f,
-                                                                primary_dxpl_id,
-                                                                secondary_dxpl_id,
-                                                                NULL,
-                                                                entry_ptr->addr,
-                                                                flags,
-                                                                &first_flush,
-                                                                FALSE);
-                                if ( status < 0 ) {
-
-                                    /* This shouldn't happen -- if it does, 
-                                     * we are toast so just scream and die.
+
+                                flushed_during_dep_loop = TRUE;
+
+                                if ((cache_ptr->slist_change_in_serialize) ||
+                                    (cache_ptr->slist_change_in_pre_serialize))
+                                {
+                                    /* The slist has been modified by something
+                                     * other than the simple removal of the 
+                                     * of the flushed entry after the flush.
+                                     * 
+                                     * This has the potential to corrupt the
+                                     * scan through the slist, so restart it.
                                      */
-                                    HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, \
-                                                "Can't flush entry.")
+                                    restart_slist_scan = TRUE;
+                                    cache_ptr->slist_change_in_pre_serialize 
+                                        = FALSE;
+                                    cache_ptr->slist_change_in_serialize 
+                                        = FALSE;
+
+                                    H5C__UPDATE_STATS_FOR_SLIST_SCAN_RESTART(cache_ptr)
                                 }
-                                flushed_during_dep_loop = TRUE;
                             } /* end if */
                             else if(entry_ptr->flush_dep_height < curr_flush_dep_height)
                                 /* This shouldn't happen -- if it does, just scream and die.  */
                                 HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL,  "dirty entry below current flush dep. height.")
                         } /* end else */
                     } /* end if */
-                } /* while ( node_ptr != NULL ) */
+                } /* while ( ( restart_slist_scan ) || ( node_ptr != NULL ) ) */
 
                 /* Check for incrementing flush dependency height */
                 if(flushed_during_dep_loop) {
@@ -2020,7 +1390,8 @@ H5C_flush_cache(H5F_t *f, hid_t primary_dxpl_id, hid_t secondary_dxpl_id, unsign
                     curr_flush_dep_height++;
 
             } /* while ( curr_flush_dep_height <= H5C__NUM_FLUSH_DEP_HEIGHTS) */
-end_of_inner_loop:
+
+            passes++;
 
 #if H5C_DO_SANITY_CHECKS
             /* Verify that the slist size and length are as expected. */
@@ -2032,8 +1403,6 @@ end_of_inner_loop:
 		       flushed_entries_size) == cache_ptr->slist_size );
 #endif /* H5C_DO_SANITY_CHECKS */
 
-	    passes++;
-
 	} /* while */
 
         HDassert( protected_entries <= cache_ptr->pl_len );
@@ -2098,12 +1467,10 @@ done:
  */
 herr_t
 H5C_flush_to_min_clean(H5F_t * f,
-                       hid_t   primary_dxpl_id,
-                       hid_t   secondary_dxpl_id)
+		       hid_t    dxpl_id)
 {
     H5C_t *             cache_ptr;
     herr_t      	result;
-    hbool_t		first_flush = TRUE;
     hbool_t		write_permitted;
 #if 0 /* modified code -- commented out for now */
     int			i;
@@ -2146,11 +1513,9 @@ H5C_flush_to_min_clean(H5F_t * f,
     }
 #if 1 /* original code */
     result = H5C_make_space_in_cache(f,
-                                     primary_dxpl_id,
-                                     secondary_dxpl_id,
+                                     dxpl_id,
                                      (size_t)0,
-                                     write_permitted,
-                                     &first_flush);
+                                     write_permitted);
 
     if ( result < 0 ) {
 
@@ -2559,6 +1924,34 @@ done:
 
 
 /*-------------------------------------------------------------------------
+ * Function:    H5C_get_aux_ptr
+ *
+ * Purpose:     Get the aux_ptr field from the cache.
+ *
+ *              This field will either be NULL (when accessing a file serially)
+ *              or contains a pointer to the auxiliary info for parallel I/O.
+ *
+ * Return:      NULL/non-NULL (can't fail)
+ *
+ * Programmer:  Quincey Koziol
+ *              6/29/15
+ *
+ *-------------------------------------------------------------------------
+ */
+void *
+H5C_get_aux_ptr(const H5C_t *cache_ptr)
+{
+    FUNC_ENTER_NOAPI_NOERR
+
+    /* Check arguments */
+    HDassert(cache_ptr);
+    HDassert(cache_ptr->magic == H5C__H5C_T_MAGIC);
+
+    FUNC_LEAVE_NOAPI(cache_ptr->aux_ptr)
+} /* H5C_get_aux_ptr() */
+
+
+/*-------------------------------------------------------------------------
  * Function:    H5C_get_trace_file_ptr
  *
  * Purpose:     Get the trace_file_ptr field from the cache.
@@ -2645,8 +2038,7 @@ H5C_get_trace_file_ptr_from_entry(const H5C_cache_entry_t *entry_ptr)
  */
 herr_t
 H5C_insert_entry(H5F_t *             f,
-                 hid_t		     primary_dxpl_id,
-                 hid_t		     secondary_dxpl_id,
+                 hid_t		     dxpl_id,
                  const H5C_class_t * type,
                  haddr_t 	     addr,
                  void *		     thing,
@@ -2654,7 +2046,6 @@ H5C_insert_entry(H5F_t *             f,
 {
     H5C_t *             cache_ptr;
     herr_t		result;
-    hbool_t		first_flush = TRUE;
     hbool_t		insert_pinned;
     hbool_t             flush_last;
 #ifdef H5_HAVE_PARALLEL
@@ -2678,8 +2069,6 @@ H5C_insert_entry(H5F_t *             f,
     HDassert( cache_ptr );
     HDassert( cache_ptr->magic == H5C__H5C_T_MAGIC );
     HDassert( type );
-    HDassert( type->flush );
-    HDassert( type->size );
     HDassert( H5F_addr_defined(addr) );
     HDassert( thing );
 
@@ -2718,15 +2107,16 @@ H5C_insert_entry(H5F_t *             f,
             HGOTO_ERROR(H5E_CACHE, H5E_CANTINS, FAIL, "duplicate entry in cache.")
     } /* end if */
 
-#ifndef NDEBUG
     entry_ptr->magic = H5C__H5C_CACHE_ENTRY_T_MAGIC;
-#endif /* NDEBUG */
     entry_ptr->cache_ptr = cache_ptr;
     entry_ptr->addr  = addr;
     entry_ptr->type  = type;
 
+    entry_ptr->image_ptr = NULL;
+    entry_ptr->image_up_to_date = FALSE;
+
     /* Apply tag to newly inserted entry */
-    if(H5C_tag_entry(cache_ptr, entry_ptr, primary_dxpl_id) < 0)
+    if(H5C_tag_entry(cache_ptr, entry_ptr, dxpl_id) < 0)
         HGOTO_ERROR(H5E_CACHE, H5E_CANTTAG, FAIL, "Cannot tag metadata entry")
 
     entry_ptr->is_protected = FALSE;
@@ -2747,10 +2137,27 @@ H5C_insert_entry(H5F_t *             f,
     /* not protected, so can't be dirtied */
     entry_ptr->dirtied  = FALSE;
 
-    /* Retrieve the size of the thing */
-    if((type->size)(f, thing, &(entry_ptr->size)) < 0)
+    /* Retrieve the size of the thing.  Set the compressed field to FALSE
+     * and the compressed_size field to zero first, as they may not be 
+     * initialized by the image_len call.
+     */
+    entry_ptr->compressed = FALSE;
+    entry_ptr->compressed_size = 0;
+    if((type->image_len)(thing, &(entry_ptr->size), &(entry_ptr->compressed), 
+                         &(entry_ptr->compressed_size)) < 0)
         HGOTO_ERROR(H5E_RESOURCE, H5E_CANTGETSIZE, FAIL, "Can't get size of thing")
     HDassert(entry_ptr->size > 0 &&  entry_ptr->size < H5C_MAX_ENTRY_SIZE);
+    HDassert(((type->flags & H5C__CLASS_COMPRESSED_FLAG) != 0) ||
+             (entry_ptr->compressed == FALSE));
+
+    /* entry has just been inserted -- thus compressed size cannot have 
+     * been computed yet.  Thus if entry_ptr->compressed is TRUE, 
+     * entry_ptr->size must equal entry_ptr->compressed_size.
+     */
+    HDassert((entry_ptr->compressed == FALSE) ||
+             (entry_ptr->size == entry_ptr->compressed_size));
+    HDassert((entry_ptr->compressed == TRUE) || 
+             (entry_ptr->compressed_size == 0));
 
     entry_ptr->in_slist = FALSE;
 
@@ -2761,7 +2168,6 @@ H5C_insert_entry(H5F_t *             f,
 
     entry_ptr->flush_in_progress = FALSE;
     entry_ptr->destroy_in_progress = FALSE;
-    entry_ptr->free_file_space_on_destroy = FALSE;
 
     /* Initialize flush dependency height fields */
     entry_ptr->flush_dep_parent = NULL;
@@ -2860,11 +2266,9 @@ H5C_insert_entry(H5F_t *             f,
          */
 
         result = H5C_make_space_in_cache(f,
-                                         primary_dxpl_id,
-                                         secondary_dxpl_id,
+                                         dxpl_id,
                                          space_needed,
-                                         write_permitted,
-                                         &first_flush);
+                                         write_permitted);
 
         if ( result < 0 ) {
 
@@ -2928,301 +2332,6 @@ done:
 
 
 /*-------------------------------------------------------------------------
- *
- * Function:    H5C_mark_entries_as_clean
- *
- * Purpose:     When the H5C code is used to implement the metadata caches
- *		in PHDF5, only the cache with MPI_rank 0 is allowed to
- *		actually write entries to disk -- all other caches must
- *		retain dirty entries until they are advised that the
- *		entries are clean.
- *
- *		This function exists to allow the H5C code to receive these
- *		notifications.
- *
- *		The function receives a list of entry base addresses
- *		which must refer to dirty entries in the cache.  If any
- *		of the entries are either clean or don't exist, the
- *		function flags an error.
- *
- *		The function scans the list of entries and flushes all
- *		those that are currently unprotected with the
- *		H5C__FLUSH_CLEAR_ONLY_FLAG.  Those that are currently
- *		protected are flagged for clearing when they are
- *		unprotected.
- *
- * Return:      Non-negative on success/Negative on failure
- *
- * Programmer:  John Mainzer
- *              7/5/05
- *
- *-------------------------------------------------------------------------
- */
-#ifdef H5_HAVE_PARALLEL
-herr_t
-H5C_mark_entries_as_clean(H5F_t *  f,
-                          hid_t     primary_dxpl_id,
-                          hid_t     secondary_dxpl_id,
-                          int32_t   ce_array_len,
-                          haddr_t * ce_array_ptr)
-{
-    H5C_t *             cache_ptr;
-    hbool_t		first_flush = TRUE;
-    int			entries_cleared;
-    int			entries_examined;
-    int                 i;
-    int			initial_list_len;
-    haddr_t		addr;
-#if H5C_DO_SANITY_CHECKS
-    int			pinned_entries_marked = 0;
-    int			protected_entries_marked = 0;
-    int			other_entries_marked = 0;
-    haddr_t		last_addr;
-#endif /* H5C_DO_SANITY_CHECKS */
-    H5C_cache_entry_t *	clear_ptr = NULL;
-    H5C_cache_entry_t *	entry_ptr = NULL;
-    herr_t		ret_value = SUCCEED;      /* Return value */
-
-    FUNC_ENTER_NOAPI(FAIL)
-
-    HDassert( f );
-    HDassert( f->shared );
-    cache_ptr = f->shared->cache;
-    HDassert( cache_ptr );
-    HDassert( cache_ptr->magic == H5C__H5C_T_MAGIC );
-
-    HDassert( ce_array_len > 0 );
-    HDassert( ce_array_ptr != NULL );
-
-#if H5C_DO_EXTREME_SANITY_CHECKS
-    if ( ( H5C_validate_protected_entry_list(cache_ptr) < 0 ) ||
-         ( H5C_validate_pinned_entry_list(cache_ptr) < 0 ) ||
-         ( H5C_validate_lru_list(cache_ptr) < 0 ) ) {
-
-        HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, \
-                    "an extreme sanity check failed on entry.\n");
-    }
-#endif /* H5C_DO_EXTREME_SANITY_CHECKS */
-
-    for ( i = 0; i < ce_array_len; i++ )
-    {
-        addr = ce_array_ptr[i];
-
-#if H5C_DO_SANITY_CHECKS
-        if ( i == 0 ) {
-
-            last_addr = addr;
-
-        } else {
-
-            if ( last_addr == addr ) {
-
-                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, \
-                            "Duplicate entry in cleaned list.\n");
-
-            } else if ( last_addr > addr ) {
-
-                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, \
-                            "cleaned list not sorted.\n");
-            }
-        }
-
-#if H5C_DO_EXTREME_SANITY_CHECKS
-        if ( ( H5C_validate_protected_entry_list(cache_ptr) < 0 ) ||
-             ( H5C_validate_pinned_entry_list(cache_ptr) < 0 ) ||
-             ( H5C_validate_lru_list(cache_ptr) < 0 ) ) {
-
-            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, \
-                        "an extreme sanity check failed in for loop.\n");
-        }
-#endif /* H5C_DO_EXTREME_SANITY_CHECKS */
-#endif /* H5C_DO_SANITY_CHECKS */
-
-        HDassert( H5F_addr_defined(addr) );
-
-        H5C__SEARCH_INDEX(cache_ptr, addr, entry_ptr, FAIL)
-
-        if ( entry_ptr == NULL ) {
-#if H5C_DO_SANITY_CHECKS
-	    HDfprintf(stdout,
-                  "H5C_mark_entries_as_clean: entry[%d] = %ld not in cache.\n",
-                      (int)i,
-                      (long)addr);
-#endif /* H5C_DO_SANITY_CHECKS */
-            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, \
-                        "Listed entry not in cache?!?!?.")
-
-        } else if ( ! entry_ptr->is_dirty ) {
-
-#if H5C_DO_SANITY_CHECKS
-	    HDfprintf(stdout,
-                      "H5C_mark_entries_as_clean: entry %ld is not dirty!?!\n",
-                      (long)addr);
-#endif /* H5C_DO_SANITY_CHECKS */
-            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, \
-                        "Listed entry not dirty?!?!?.")
-#if 0 /* original code */
-        } else if ( entry_ptr->is_protected ) {
-
-            entry_ptr->clear_on_unprotect = TRUE;
-
-        } else {
-
-            if ( H5C_flush_single_entry(f,
-                                        primary_dxpl_id,
-                                        secondary_dxpl_id,
-                                        entry_ptr->type,
-                                        addr,
-                                        H5C__FLUSH_CLEAR_ONLY_FLAG,
-                                        &first_flush,
-                                        TRUE) < 0 ) {
-
-                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't clear entry.")
-            }
-        }
-#else /* modified code */
-        } else {
-            /* Mark the entry to be cleared on unprotect.  We will
-             * scan the LRU list shortly, and clear all those entries
-             * not currently protected.
-             */
-            entry_ptr->clear_on_unprotect = TRUE;
-#if H5C_DO_SANITY_CHECKS
-	    if ( entry_ptr->is_protected ) {
-
-		protected_entries_marked++;
-
-	    } else if ( entry_ptr->is_pinned ) {
-
-		pinned_entries_marked++;
-
-	    } else {
-
-		other_entries_marked++;
-	    }
-#endif /* H5C_DO_SANITY_CHECKS */
-        }
-#endif /* end modified code */
-    }
-#if 1 /* modified code */
-    /* Scan through the LRU list from back to front, and flush the
-     * entries whose clear_on_unprotect flags are set.  Observe that
-     * any protected entries will not be on the LRU, and therefore
-     * will not be flushed at this time.
-     */
-
-    entries_cleared = 0;
-    entries_examined = 0;
-    initial_list_len = cache_ptr->LRU_list_len;
-    entry_ptr = cache_ptr->LRU_tail_ptr;
-
-    while ( ( entry_ptr != NULL ) &&
-            ( entries_examined <= initial_list_len ) &&
-            ( entries_cleared < ce_array_len ) )
-    {
-        if ( entry_ptr->clear_on_unprotect ) {
-
-            entry_ptr->clear_on_unprotect = FALSE;
-            clear_ptr = entry_ptr;
-            entry_ptr = entry_ptr->prev;
-            entries_cleared++;
-
-            if ( H5C_flush_single_entry(f,
-                                        primary_dxpl_id,
-                                        secondary_dxpl_id,
-                                        clear_ptr->type,
-                                        clear_ptr->addr,
-                                        H5C__FLUSH_CLEAR_ONLY_FLAG,
-                                        &first_flush,
-                                        TRUE) < 0 ) {
-
-                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't clear entry.")
-            }
-        } else {
-
-            entry_ptr = entry_ptr->prev;
-        }
-        entries_examined++;
-    }
-
-#if H5C_DO_SANITY_CHECKS
-    HDassert( entries_cleared == other_entries_marked );
-#endif /* H5C_DO_SANITY_CHECKS */
-
-    /* It is also possible that some of the cleared entries are on the
-     * pinned list.  Must scan that also.
-     */
-
-    entry_ptr = cache_ptr->pel_head_ptr;
-
-    while ( entry_ptr != NULL )
-    {
-        if ( entry_ptr->clear_on_unprotect ) {
-
-            entry_ptr->clear_on_unprotect = FALSE;
-            clear_ptr = entry_ptr;
-            entry_ptr = entry_ptr->next;
-            entries_cleared++;
-
-            if ( H5C_flush_single_entry(f,
-                                        primary_dxpl_id,
-                                        secondary_dxpl_id,
-                                        clear_ptr->type,
-                                        clear_ptr->addr,
-                                        H5C__FLUSH_CLEAR_ONLY_FLAG,
-                                        &first_flush,
-                                        TRUE) < 0 ) {
-
-                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't clear entry.")
-            }
-        } else {
-
-            entry_ptr = entry_ptr->next;
-        }
-    }
-
-#if H5C_DO_SANITY_CHECKS
-    HDassert( entries_cleared == pinned_entries_marked + other_entries_marked );
-    HDassert( entries_cleared + protected_entries_marked == ce_array_len );
-#endif /* H5C_DO_SANITY_CHECKS */
-
-    HDassert( ( entries_cleared == ce_array_len ) ||
-              ( (ce_array_len - entries_cleared) <= cache_ptr->pl_len ) );
-
-#if H5C_DO_SANITY_CHECKS
-    i = 0;
-    entry_ptr = cache_ptr->pl_head_ptr;
-    while ( entry_ptr != NULL )
-    {
-        if ( entry_ptr->clear_on_unprotect ) {
-
-            i++;
-        }
-        entry_ptr = entry_ptr->next;
-    }
-    HDassert( (entries_cleared + i) == ce_array_len );
-#endif /* H5C_DO_SANITY_CHECKS */
-#endif /* modified code */
-
-done:
-
-#if H5C_DO_EXTREME_SANITY_CHECKS
-    if ( ( H5C_validate_protected_entry_list(cache_ptr) < 0 ) ||
-         ( H5C_validate_pinned_entry_list(cache_ptr) < 0 ) ||
-         ( H5C_validate_lru_list(cache_ptr) < 0 ) ) {
-
-        HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, \
-                    "an extreme sanity check failed on exit.\n");
-    }
-#endif /* H5C_DO_EXTREME_SANITY_CHECKS */
-
-    FUNC_LEAVE_NOAPI(ret_value)
-
-} /* H5C_mark_entries_as_clean() */
-#endif /* H5_HAVE_PARALLEL */
-
-
-/*-------------------------------------------------------------------------
  * Function:    H5C_mark_entry_dirty
  *
  * Purpose:	Mark a pinned or protected entry as dirty.  The target entry
@@ -3278,6 +2387,7 @@ H5C_mark_entry_dirty(void *thing)
 
         /* mark the entry as dirty if it isn't already */
         entry_ptr->is_dirty = TRUE;
+	entry_ptr->image_up_to_date = FALSE;
 
 	if ( was_pinned_unprotected_and_clean ) {
 
@@ -3427,36 +2537,32 @@ H5C_move_entry(H5C_t *	     cache_ptr,
         was_dirty = entry_ptr->is_dirty;
 #endif /* H5C_MAINTAIN_CLEAN_AND_DIRTY_LRU_LISTS */
 
-	if ( ! ( entry_ptr->flush_in_progress ) ) {
-
-            entry_ptr->is_dirty = TRUE;
-	}
+        entry_ptr->is_dirty = TRUE;
+        /* This shouldn't be needed, but it keeps the test code happy */
+        entry_ptr->image_up_to_date = FALSE;
 
         H5C__INSERT_IN_INDEX(cache_ptr, entry_ptr, FAIL)
 
-	if ( ! ( entry_ptr->flush_in_progress ) ) {
-
-            H5C__INSERT_ENTRY_IN_SLIST(cache_ptr, entry_ptr, FAIL)
+        H5C__INSERT_ENTRY_IN_SLIST(cache_ptr, entry_ptr, FAIL)
 
 #if H5C_DO_SANITY_CHECKS
 
-            if ( removed_entry_from_slist ) {
-
-		/* we just removed the entry from the slist.  Thus we
-		 * must touch up cache_ptr->slist_len_increase and
-		 * cache_ptr->slist_size_increase to keep from skewing
-		 * the sanity checks.
-		 */
-		HDassert( cache_ptr->slist_len_increase > 1 );
-		HDassert( cache_ptr->slist_size_increase > 
-                          (int64_t)(entry_ptr->size) );
+        if ( removed_entry_from_slist ) {
 
-		cache_ptr->slist_len_increase -= 1;
-		cache_ptr->slist_size_increase -= (int64_t)(entry_ptr->size);
-	    }
+	    /* we just removed the entry from the slist.  Thus we
+	     * must touch up cache_ptr->slist_len_increase and
+	     * cache_ptr->slist_size_increase to keep from skewing
+	     * the sanity checks.
+	     */
+	    cache_ptr->slist_len_increase -= 1;
+	    cache_ptr->slist_size_increase -= (int64_t)(entry_ptr->size);
+        }
 
 #endif /* H5C_DO_SANITY_CHECKS */
 
+	if ( ! ( entry_ptr->flush_in_progress ) ) {
+
+            /* skip the update if a flush is in progress */
             H5C__UPDATE_RP_FOR_MOVE(cache_ptr, entry_ptr, was_dirty, FAIL)
         }
     }
@@ -3536,6 +2642,11 @@ H5C_resize_entry(void *thing, size_t new_size)
 
         /* mark the entry as dirty if it isn't already */
         entry_ptr->is_dirty = TRUE;
+        entry_ptr->image_up_to_date = FALSE;
+
+        /* Release the current image */
+        if( entry_ptr->image_ptr )
+            entry_ptr->image_ptr = H5MM_xfree(entry_ptr->image_ptr);
 
         /* do a flash cache size increase if appropriate */
         if ( cache_ptr->flash_size_increase_possible ) {
@@ -3743,18 +2854,6 @@ done:
  *		or flushed -- nor may it be accessed by another call to
  *		H5C_protect.  Any attempt to do so will result in a failure.
  *
- *		The primary_dxpl_id and secondary_dxpl_id parameters
- *		specify the dxpl_ids used on the first write occasioned
- *		by the insertion (primary_dxpl_id), and on all subsequent
- *		writes (secondary_dxpl_id).  This is useful in the
- *		metadata cache, but may not be needed elsewhere.  If so,
- *		just use the same dxpl_id for both parameters.
- *
- *		All reads are performed with the primary_dxpl_id.
- *
- *		Similarly, the primary_dxpl_id is passed to the
- *		check_write_permitted function if it is called.
- *
  * Return:      Success:        Ptr to the desired entry
  *              Failure:        NULL
  *
@@ -3776,12 +2875,21 @@ done:
  *              entries long before we actually have to evict something
  *              to make space.
  *
+ *		JRM -- 9/1/14
+ *		Replace the old rw parameter with the flags parameter.
+ *		This allows H5C_protect to accept flags other than 
+ *		H5C__READ_ONLY_FLAG.  
+ *
+ *		Added support for the H5C__FLUSH_LAST_FLAG and 
+ *		H5C__FLUSH_COLLECTIVELY_FLAG flags.  At present, these 
+ *		flags are only applied if the entry is not in cache, and 
+ *		is loaded into the cache as a result of this call.
+ *
  *-------------------------------------------------------------------------
  */
 void *
 H5C_protect(H5F_t *		f,
-            hid_t	        primary_dxpl_id,
-            hid_t	        secondary_dxpl_id,
+            hid_t	        dxpl_id,
             const H5C_class_t * type,
             haddr_t 	        addr,
             void *              udata,
@@ -3789,16 +2897,17 @@ H5C_protect(H5F_t *		f,
 {
     H5C_t *		cache_ptr;
     hbool_t		hit;
-    hbool_t		first_flush;
     hbool_t		have_write_permitted = FALSE;
     hbool_t		read_only = FALSE;
+    hbool_t             flush_last;
+#ifdef H5_HAVE_PARALLEL
+    hbool_t             flush_collectively;
+#endif /* H5_HAVE_PARALLEL */
     hbool_t		write_permitted;
     herr_t		result;
     size_t		empty_space;
     void *		thing;
     H5C_cache_entry_t *	entry_ptr;
-    haddr_t     tag = HADDR_UNDEF;
-    H5P_genplist_t *dxpl;    /* dataset transfer property list */
     void *		ret_value;      /* Return value */
 
     FUNC_ENTER_NOAPI(NULL)
@@ -3812,8 +2921,6 @@ H5C_protect(H5F_t *		f,
     HDassert( cache_ptr );
     HDassert( cache_ptr->magic == H5C__H5C_T_MAGIC );
     HDassert( type );
-    HDassert( type->flush );
-    HDassert( type->load );
     HDassert( H5F_addr_defined(addr) );
 
 #if H5C_DO_EXTREME_SANITY_CHECKS
@@ -3827,6 +2934,10 @@ H5C_protect(H5F_t *		f,
 #endif /* H5C_DO_EXTREME_SANITY_CHECKS */
 
     read_only          = ( (flags & H5C__READ_ONLY_FLAG) != 0 );
+    flush_last         = ( (flags & H5C__FLUSH_LAST_FLAG) != 0 );
+#ifdef H5_HAVE_PARALLEL
+    flush_collectively = ( (flags & H5C__FLUSH_COLLECTIVELY_FLAG) != 0 );
+#endif /* H5_HAVE_PARALLEL */
 
     /* first check to see if the target is in cache */
     H5C__SEARCH_INDEX(cache_ptr, addr, entry_ptr, NULL)
@@ -3838,6 +2949,10 @@ H5C_protect(H5F_t *		f,
             HGOTO_ERROR(H5E_CACHE, H5E_BADTYPE, NULL, "incorrect cache entry type")
 
 #if H5C_DO_TAGGING_SANITY_CHECKS
+{
+        H5P_genplist_t *dxpl;    /* dataset transfer property list */
+        haddr_t     tag = HADDR_UNDEF;
+
         /* The entry is already in the cache, but make sure that the tag value 
            being passed in via dxpl is still legal. This will ensure that had
            the entry NOT been in the cache, tagging was still set up correctly
@@ -3845,7 +2960,7 @@ H5C_protect(H5F_t *		f,
            from disk. */
 
         /* Get the dataset transfer property list */
-        if(NULL == (dxpl = (H5P_genplist_t *)H5I_object_verify(primary_dxpl_id, H5I_GENPROP_LST)))
+        if(NULL == (dxpl = (H5P_genplist_t *)H5I_object_verify(dxpl_id, H5I_GENPROP_LST)))
             HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not a property list");
 
         /* Get the tag from the DXPL */
@@ -3860,6 +2975,7 @@ H5C_protect(H5F_t *		f,
                 HGOTO_ERROR(H5E_CACHE, H5E_CANTGET, NULL, "tag verification failed");
 
         } /* end if */
+}
 #endif
 
         hit = TRUE;
@@ -3871,7 +2987,7 @@ H5C_protect(H5F_t *		f,
 
         hit = FALSE;
 
-        thing = H5C_load_entry(f, primary_dxpl_id, type, addr, udata);
+        thing = H5C_load_entry(f, dxpl_id, type, addr, udata);
 
         if ( thing == NULL ) {
 
@@ -3881,7 +2997,7 @@ H5C_protect(H5F_t *		f,
         entry_ptr = (H5C_cache_entry_t *)thing;
 
         /* Apply tag to newly protected entry */
-        if(H5C_tag_entry(cache_ptr, entry_ptr, primary_dxpl_id) < 0)
+        if(H5C_tag_entry(cache_ptr, entry_ptr, dxpl_id) < 0)
             HGOTO_ERROR(H5E_CACHE, H5E_CANTTAG, NULL, "Cannot tag metadata entry")
 
         /* If the entry is very large, and we are configured to allow it,
@@ -3936,7 +3052,6 @@ H5C_protect(H5F_t *		f,
 
                     have_write_permitted = TRUE;
 
-                    first_flush = TRUE;
                 }
             } else {
 
@@ -3944,7 +3059,6 @@ H5C_protect(H5F_t *		f,
 
                 have_write_permitted = TRUE;
 
-                first_flush = TRUE;
             }
 
             HDassert( entry_ptr->size <= H5C_MAX_ENTRY_SIZE );
@@ -3985,10 +3099,10 @@ H5C_protect(H5F_t *		f,
              * see no point in worrying about the fourth.
              */
 
-            result = H5C_make_space_in_cache(f, primary_dxpl_id,
-                                             secondary_dxpl_id,
-                                             space_needed, write_permitted,
-                                             &first_flush);
+            result = H5C_make_space_in_cache(f, 
+                                             dxpl_id, 
+                                             space_needed,
+                                             write_permitted);
 
             if ( result < 0 ) {
 
@@ -4002,7 +3116,24 @@ H5C_protect(H5F_t *		f,
          *
          * This is no longer true -- due to a bug fix, we may modify
          * data on load to repair a file.
+         *
+         *   *******************************************
+         *
+         * Set the flush_last (and possibly flush_collectively) fields 
+ 	 * of the newly loaded entry before inserting it into the 
+         * index.  Must do this, as the index tracked the number of 
+         * entries with the flush_last field set, but assumes that 
+         * the field will not change after insertion into the index.
+         *
+         * Note that this means that the H5C__FLUSH_LAST_FLAG and 
+         * H5C__FLUSH_COLLECTIVELY_FLAG flags are ignored if the 
+         * entry is already in cache.
          */
+        entry_ptr->flush_me_last = flush_last;
+#ifdef H5_HAVE_PARALLEL
+        entry_ptr->flush_me_collectively = flush_collectively;
+#endif
+
         H5C__INSERT_IN_INDEX(cache_ptr, entry_ptr, NULL)
 
         if ( ( entry_ptr->is_dirty ) && ( ! (entry_ptr->in_slist) ) ) {
@@ -4017,11 +3148,11 @@ H5C_protect(H5F_t *		f,
          */
         H5C__UPDATE_RP_FOR_INSERTION(cache_ptr, entry_ptr, NULL)
 
-        /* If the entry's type has a 'notify' callback send a 'after insertion'
+        /* If the entry's type has a 'notify' callback send a 'after load'
          * notice now that the entry is fully integrated into the cache.
          */
         if(entry_ptr->type->notify &&
-                (entry_ptr->type->notify)(H5C_NOTIFY_ACTION_AFTER_INSERT, entry_ptr) < 0)
+                (entry_ptr->type->notify)(H5C_NOTIFY_ACTION_AFTER_LOAD, entry_ptr) < 0)
             HGOTO_ERROR(H5E_CACHE, H5E_CANTNOTIFY, NULL, "can't notify client about entry inserted into cache")
     }
 
@@ -4083,7 +3214,6 @@ H5C_protect(H5F_t *		f,
 
                     have_write_permitted = TRUE;
 
-                    first_flush = TRUE;
                 }
             } else {
 
@@ -4091,7 +3221,6 @@ H5C_protect(H5F_t *		f,
 
                 have_write_permitted = TRUE;
 
-                first_flush = TRUE;
             }
         }
 
@@ -4100,10 +3229,8 @@ H5C_protect(H5F_t *		f,
                (cache_ptr->resize_ctl).epoch_length ) ) {
 
             result = H5C__auto_adjust_cache_size(f,
-                                                 primary_dxpl_id,
-                                                 secondary_dxpl_id,
-                                                 write_permitted,
-                                                 &first_flush);
+                                                 dxpl_id,
+                                                 write_permitted);
             if ( result != SUCCEED ) {
 
                 HGOTO_ERROR(H5E_CACHE, H5E_CANTPROTECT, NULL, \
@@ -4137,10 +3264,10 @@ H5C_protect(H5F_t *		f,
 		if(cache_ptr->index_size > cache_ptr->max_cache_size)
                     cache_ptr->cache_full = TRUE;
 
-                result = H5C_make_space_in_cache(f, primary_dxpl_id,
-                                                 secondary_dxpl_id,
-                                                 (size_t)0, write_permitted,
-                                                 &first_flush);
+                result = H5C_make_space_in_cache(f,
+                                                 dxpl_id,
+                                                 (size_t)0,
+                                                 write_permitted);
 
                 if ( result < 0 ) {
 
@@ -4636,6 +3763,10 @@ done:
  *              total_entries_skipped_in_msic, total_entries_scanned_in_msic,
  *              and max_entries_skipped_in_msic fields.
  *
+ *		JRM -- 4/11/15
+ *		Added code displaying the new slist_scan_restarts,
+ *		LRU_scan_restarts, and hash_bucket_scan_restarts fields;
+ *
  *-------------------------------------------------------------------------
  */
 herr_t
@@ -4659,6 +3790,7 @@ H5C_stats(H5C_t * cache_ptr,
     int64_t     total_clears = 0;
     int64_t     total_flushes = 0;
     int64_t     total_evictions = 0;
+    int64_t     total_take_ownerships = 0;
     int64_t     total_moves = 0;
     int64_t     total_entry_flush_moves = 0;
     int64_t     total_cache_flush_moves = 0;
@@ -4687,6 +3819,8 @@ H5C_stats(H5C_t * cache_ptr,
 
     FUNC_ENTER_NOAPI(FAIL)
 
+    HDassert( cache_ptr->magic == H5C__H5C_T_MAGIC );
+
     /* This would normally be an assert, but we need to use an HGOTO_ERROR
      * call to shut up the compiler.
      */
@@ -4713,6 +3847,7 @@ H5C_stats(H5C_t * cache_ptr,
         total_clears            += cache_ptr->clears[i];
         total_flushes           += cache_ptr->flushes[i];
         total_evictions         += cache_ptr->evictions[i];
+        total_take_ownerships   += cache_ptr->take_ownerships[i];
         total_moves             += cache_ptr->moves[i];
 	total_entry_flush_moves += cache_ptr->entry_flush_moves[i];
 	total_cache_flush_moves += cache_ptr->cache_flush_moves[i];
@@ -4864,11 +3999,16 @@ H5C_stats(H5C_t * cache_ptr,
               (long)max_read_protects);
 
     HDfprintf(stdout,
-              "%s  Total clears / flushes / evictions = %ld / %ld / %ld\n",
+              "%s  Total clears / flushes             = %ld / %ld\n",
               cache_ptr->prefix,
               (long)total_clears,
-              (long)total_flushes,
-              (long)total_evictions);
+              (long)total_flushes);
+
+    HDfprintf(stdout,
+              "%s  Total evictions / take ownerships  = %ld / %ld\n",
+              cache_ptr->prefix,
+              (long)total_evictions,
+              (long)total_take_ownerships);
 
     HDfprintf(stdout,
 	      "%s  Total insertions(pinned) / moves   = %ld(%ld) / %ld\n",
@@ -4940,6 +4080,13 @@ H5C_stats(H5C_t * cache_ptr,
               (long long)(cache_ptr->total_entries_scanned_in_msic -
                             cache_ptr->entries_scanned_to_make_space));
 
+    HDfprintf(stdout, 
+              "%s  slist/LRU/hash bkt scan restarts   = %lld / %lld / %lld.\n",
+              cache_ptr->prefix, 
+              (long long)(cache_ptr->slist_scan_restarts),
+              (long long)(cache_ptr->LRU_scan_restarts),
+              (long long)(cache_ptr->hash_bucket_scan_restarts));
+
 #if H5C_COLLECT_CACHE_ENTRY_STATS
 
     HDfprintf(stdout, "%s  aggregate max / min accesses       = %d / %d\n",
@@ -4993,11 +4140,16 @@ H5C_stats(H5C_t * cache_ptr,
                       (int)(cache_ptr->max_read_protects[i]));
 
             HDfprintf(stdout,
-                     "%s    clears / flushes / evictions   = %ld / %ld / %ld\n",
+                      "%s    clears / flushes               = %ld / %ld\n", 
                       cache_ptr->prefix,
                       (long)(cache_ptr->clears[i]),
-                      (long)(cache_ptr->flushes[i]),
-                      (long)(cache_ptr->evictions[i]));
+                      (long)(cache_ptr->flushes[i]));
+
+            HDfprintf(stdout,
+                      "%s    evictions / take ownerships    = %ld / %ld\n",
+                      cache_ptr->prefix,
+                      (long)(cache_ptr->evictions[i]),
+                      (long)(cache_ptr->take_ownerships[i]));
 
             HDfprintf(stdout,
                       "%s    insertions(pinned) / moves     = %ld(%ld) / %ld\n",
@@ -5092,6 +4244,11 @@ done:
  *              total_entries_skipped_in_msic, total_entries_scanned_in_msic,
  *              and max_entries_skipped_in_msic fields.
  *
+ *		JRM 4/11/15
+ *		Added code to initialize the new slist_scan_restarts,
+ *		LRU_scan_restarts, hash_bucket_scan_restarts, and 
+ *		take_ownerships fields.
+ *
  *-------------------------------------------------------------------------
  */
 void
@@ -5125,6 +4282,7 @@ H5C_stats__reset(H5C_t H5_ATTR_UNUSED * cache_ptr)
         cache_ptr->clears[i]			= 0;
         cache_ptr->flushes[i]			= 0;
         cache_ptr->evictions[i]	 		= 0;
+        cache_ptr->take_ownerships[i] 		= 0;
         cache_ptr->moves[i]	 		= 0;
         cache_ptr->entry_flush_moves[i]		= 0;
         cache_ptr->cache_flush_moves[i]		= 0;
@@ -5167,6 +4325,10 @@ H5C_stats__reset(H5C_t H5_ATTR_UNUSED * cache_ptr)
     cache_ptr->max_entries_scanned_in_msic      = 0;
     cache_ptr->entries_scanned_to_make_space    = 0;
 
+    cache_ptr->slist_scan_restarts		= 0;
+    cache_ptr->LRU_scan_restarts		= 0;
+    cache_ptr->hash_bucket_scan_restarts	= 0;
+
 #if H5C_COLLECT_CACHE_ENTRY_STATS
 
     for ( i = 0; i <= cache_ptr->max_type_id; i++ )
@@ -5319,6 +4481,107 @@ done:
 
 
 /*-------------------------------------------------------------------------
+ * Function:    H5C_dump_cache_skip_list
+ *
+ * Purpose:     Debugging routine that prints a summary of the contents of 
+ *		the skip list used by the metadata cache metadata cache to 
+ *		maintain an address sorted list of dirty entries.
+ *
+ * Return:      Non-negative on success/Negative on failure
+ *
+ * Programmer:  John Mainzer
+ *              11/15/14
+ *
+ *-------------------------------------------------------------------------
+ */
+#if 0 /* debugging routine */
+herr_t
+H5C_dump_cache_skip_list(H5C_t * cache_ptr, char * calling_fcn)
+{
+    herr_t              ret_value = SUCCEED;   /* Return value */
+    int                 i;
+    H5C_cache_entry_t * entry_ptr = NULL;
+    H5SL_node_t *       node_ptr = NULL;
+
+    FUNC_ENTER_NOAPI(FAIL)
+
+    HDassert(cache_ptr != NULL);
+    HDassert(cache_ptr->magic == H5C__H5C_T_MAGIC);
+    HDassert(calling_fcn != NULL);
+
+    HDfprintf(stdout, "\n\nDumping metadata cache skip list from %s.\n",
+              calling_fcn);
+    HDfprintf(stdout, "	slist len = %d.\n", cache_ptr->slist_len);
+    HDfprintf(stdout, "	slist size = %lld.\n", 
+              (long long)(cache_ptr->slist_size));
+
+    if ( cache_ptr->slist_len > 0 )
+    {
+        /* If we get this far, all entries in the cache are listed in the
+         * skip list -- scan the skip list generating the desired output.
+         */
+
+        HDfprintf(stdout,
+                  "Num:    Addr:               Len: Prot/Pind: Dirty: Type:\n");
+
+        i = 0;
+
+        node_ptr = H5SL_first(cache_ptr->slist_ptr);
+
+        if ( node_ptr != NULL ) {
+
+            entry_ptr = (H5C_cache_entry_t *)H5SL_item(node_ptr);
+
+        } else {
+
+            entry_ptr = NULL;
+        }
+
+        while ( entry_ptr != NULL ) {
+
+            HDassert( entry_ptr->magic == H5C__H5C_CACHE_ENTRY_T_MAGIC );
+
+            HDfprintf(stdout,
+               "%s%d       0x%016llx  %4lld    %d/%d       %d    %s\n",
+               cache_ptr->prefix, i,
+               (long long)(entry_ptr->addr),
+               (long long)(entry_ptr->size),
+               (int)(entry_ptr->is_protected),
+               (int)(entry_ptr->is_pinned),
+               (int)(entry_ptr->is_dirty),
+               entry_ptr->type->name);
+
+            HDfprintf(stdout, "		node_ptr = 0x%llx, item = 0x%llx\n",
+                      (unsigned long long)node_ptr,
+                      (unsigned long long)H5SL_item(node_ptr));
+
+            /* increment node_ptr before we delete its target */
+            node_ptr = H5SL_next(node_ptr);
+
+            if ( node_ptr != NULL ) {
+
+                entry_ptr = (H5C_cache_entry_t *)H5SL_item(node_ptr);
+
+            } else {
+
+                entry_ptr = NULL;
+            }
+
+            i++;
+        }
+    }
+
+    HDfprintf(stdout, "\n\n");
+
+done:
+
+    FUNC_LEAVE_NOAPI(ret_value)
+
+} /* H5C_dump_cache_skip_list() */
+#endif /* debugging routine */
+
+
+/*-------------------------------------------------------------------------
  * Function:    H5C_unpin_entry_from_client()
  *
  * Purpose:	Internal routine to unpin a cache entry from a client action.
@@ -5447,18 +4710,6 @@ done:
  *		argument must be the value returned by that call to
  *		H5C_protect().
  *
- *		The primary_dxpl_id and secondary_dxpl_id parameters
- *		specify the dxpl_ids used on the first write occasioned
- *		by the unprotect (primary_dxpl_id), and on all subsequent
- *		writes (secondary_dxpl_id).  Since an uprotect cannot
- *		occasion a write at present, all this is moot for now.
- *		However, things change, and in any case,
- *		H5C_flush_single_entry() needs primary_dxpl_id and
- *		secondary_dxpl_id in its parameter list.
- *
- *		The function can't cause a read either, so the dxpl_id
- *		parameters are moot in this case as well.
- *
  * Return:      Non-negative on success/Negative on failure
  *
  *		If the deleted flag is TRUE, simply remove the target entry
@@ -5474,9 +4725,7 @@ done:
  */
 herr_t
 H5C_unprotect(H5F_t *		  f,
-              hid_t		  primary_dxpl_id,
-              hid_t		  secondary_dxpl_id,
-              const H5C_class_t * type,
+              hid_t		  dxpl_id,
               haddr_t		  addr,
               void *		  thing,
               unsigned int        flags)
@@ -5514,9 +4763,6 @@ H5C_unprotect(H5F_t *		  f,
 
     HDassert( cache_ptr );
     HDassert( cache_ptr->magic == H5C__H5C_T_MAGIC );
-    HDassert( type );
-    HDassert( type->clear );
-    HDassert( type->flush );
     HDassert( H5F_addr_defined(addr) );
     HDassert( thing );
     HDassert( ! ( pin_entry && unpin_entry ) );
@@ -5527,7 +4773,6 @@ H5C_unprotect(H5F_t *		  f,
     entry_ptr = (H5C_cache_entry_t *)thing;
 
     HDassert( entry_ptr->addr == addr );
-    HDassert( entry_ptr->type == type );
 
     /* also set the dirtied variable if the dirtied field is set in
      * the entry.
@@ -5615,6 +4860,19 @@ H5C_unprotect(H5F_t *		  f,
         /* Mark the entry as dirty if appropriate */
         entry_ptr->is_dirty = (entry_ptr->is_dirty || dirtied);
 
+        /* the image_up_to_date field was introduced to support 
+         * journaling.  Until we re-introduce journaling, this 
+         * field should be equal to !entry_ptr->is_dirty.  
+         *
+         * When journaling is re-enabled it should be set 
+         * to FALSE if dirtied is TRUE.
+         */
+#if 1 /* JRM */
+	entry_ptr->image_up_to_date = FALSE;
+#else /* JRM */
+	entry_ptr->image_up_to_date = !entry_ptr->is_dirty;
+#endif /* JRM */
+
         /* Update index for newly dirtied entry */
         if(was_clean && entry_ptr->is_dirty)
 	    H5C__UPDATE_INDEX_FOR_ENTRY_DIRTY(cache_ptr, entry_ptr)
@@ -5656,13 +4914,6 @@ H5C_unprotect(H5F_t *		  f,
          *                                             JRM - 5/19/04
          */
         if ( deleted ) {
-
-            /* the following first flush flag will never be used as we are
-             * calling H5C_flush_single_entry with both the
-             * H5C__FLUSH_CLEAR_ONLY_FLAG and H5C__FLUSH_INVALIDATE_FLAG flags.
-	     * However, it is needed for the function call.
-             */
-            hbool_t	dummy_first_flush = TRUE;
             unsigned    flush_flags = (H5C__FLUSH_CLEAR_ONLY_FLAG |
                                          H5C__FLUSH_INVALIDATE_FLAG);
 
@@ -5670,76 +4921,51 @@ H5C_unprotect(H5F_t *		  f,
 	    HDassert ( ! (entry_ptr->is_pinned ) );
 
             /* verify that the target entry is in the cache. */
-
             H5C__SEARCH_INDEX(cache_ptr, addr, test_entry_ptr, FAIL)
+            if(test_entry_ptr == NULL)
+                HGOTO_ERROR(H5E_CACHE, H5E_CANTUNPROTECT, FAIL, "entry not in hash table?!?.")
+            else if(test_entry_ptr != entry_ptr)
+                HGOTO_ERROR(H5E_CACHE, H5E_CANTUNPROTECT, FAIL, "hash table contains multiple entries for addr?!?.")
 
-            if ( test_entry_ptr == NULL ) {
-
-                HGOTO_ERROR(H5E_CACHE, H5E_CANTUNPROTECT, FAIL, \
-                            "entry not in hash table?!?.")
-            }
-            else if ( test_entry_ptr != entry_ptr ) {
-
-                HGOTO_ERROR(H5E_CACHE, H5E_CANTUNPROTECT, FAIL, \
-                            "hash table contains multiple entries for addr?!?.")
-            }
-
-            /* Pass along 'free file space' flag to cache client */
-
-            entry_ptr->free_file_space_on_destroy = free_file_space;
+            /* Set the 'free file space' flag for the flush, if needed */
+            if(free_file_space)
+                flush_flags |= H5C__FREE_FILE_SPACE_FLAG;
 
             /* Set the "take ownership" flag for the flush, if needed */
             if(take_ownership)
                 flush_flags |= H5C__TAKE_OWNERSHIP_FLAG;
 
-            if ( H5C_flush_single_entry(f,
-                                        primary_dxpl_id,
-                                        secondary_dxpl_id,
-                                        type,
-                                        addr,
-                                        flush_flags,
-                                        &dummy_first_flush,
-                                        TRUE) < 0 ) {
+            /* Delete the entry from the skip list on destroy */
+            flush_flags |= H5C__DEL_FROM_SLIST_ON_DESTROY_FLAG;
+
+            if(H5C__flush_single_entry(f, dxpl_id, entry_ptr, flush_flags, NULL) < 0)
+                HGOTO_ERROR(H5E_CACHE, H5E_CANTUNPROTECT, FAIL, "Can't flush entry")
 
-                HGOTO_ERROR(H5E_CACHE, H5E_CANTUNPROTECT, FAIL, "Can't flush.")
+#if H5C_DO_SANITY_CHECKS
+	    if ( ( take_ownership ) && ( ! was_clean ) )
+            {
+                /* we have just removed an entry from the skip list.  Thus 
+                 * we must touch up cache_ptr->slist_len_increase and
+                 * cache_ptr->slist_size_increase to keep from skewing
+                 * the sanity checks on flushes.
+                 */
+                cache_ptr->slist_len_increase -= 1;
+                cache_ptr->slist_size_increase -= (int64_t)(entry_ptr->size);
             }
+#endif /* H5C_DO_SANITY_CHECKS */
         }
 #ifdef H5_HAVE_PARALLEL
         else if ( clear_entry ) {
 
-            /* the following first flush flag will never be used as we are
-             * calling H5C_flush_single_entry with the
-	     * H5C__FLUSH_CLEAR_ONLY_FLAG flag.  However, it is needed for
-	     * the function call.
-             */
-            hbool_t		dummy_first_flush = TRUE;
-
             /* verify that the target entry is in the cache. */
-
             H5C__SEARCH_INDEX(cache_ptr, addr, test_entry_ptr, FAIL)
+            if(test_entry_ptr == NULL)
+                HGOTO_ERROR(H5E_CACHE, H5E_CANTUNPROTECT, FAIL, "entry not in hash table?!?.")
+            else if(test_entry_ptr != entry_ptr)
+                HGOTO_ERROR(H5E_CACHE, H5E_CANTUNPROTECT, FAIL, "hash table contains multiple entries for addr?!?.")
 
-            if ( test_entry_ptr == NULL ) {
-
-                HGOTO_ERROR(H5E_CACHE, H5E_CANTUNPROTECT, FAIL, \
-                            "entry not in hash table?!?.")
-            }
-            else if ( test_entry_ptr != entry_ptr ) {
-
-                HGOTO_ERROR(H5E_CACHE, H5E_CANTUNPROTECT, FAIL, \
-                            "hash table contains multiple entries for addr?!?.")
-            }
-
-            if ( H5C_flush_single_entry(f,
-                                        primary_dxpl_id,
-                                        secondary_dxpl_id,
-                                        type,
-                                        addr,
-                                        H5C__FLUSH_CLEAR_ONLY_FLAG,
-                                        &dummy_first_flush,
-                                        TRUE) < 0 ) {
-
-                HGOTO_ERROR(H5E_CACHE, H5E_CANTUNPROTECT, FAIL, "Can't clear.")
-            }
+            if(H5C__flush_single_entry(f, dxpl_id, entry_ptr, H5C__FLUSH_CLEAR_ONLY_FLAG | H5C__DEL_FROM_SLIST_ON_DESTROY_FLAG, NULL) < 0)
+                HGOTO_ERROR(H5E_CACHE, H5E_CANTUNPROTECT, FAIL, "Can't clear entry")
         }
 #endif /* H5_HAVE_PARALLEL */
     }
@@ -6392,10 +5618,8 @@ done:
  */
 static herr_t
 H5C__auto_adjust_cache_size(H5F_t * f,
-                            hid_t primary_dxpl_id,
-                            hid_t secondary_dxpl_id,
-                            hbool_t write_permitted,
-                            hbool_t * first_flush_ptr)
+                            hid_t dxpl_id,
+                            hbool_t write_permitted)
 {
     H5C_t *			cache_ptr = f->shared->cache;
     herr_t			result;
@@ -6596,13 +5820,11 @@ H5C__auto_adjust_cache_size(H5F_t * f,
                     } else {
 
                         result = H5C__autoadjust__ageout(f,
+                                                         dxpl_id,
                                                          hit_rate,
                                                          &status,
                                                          &new_max_cache_size,
-                                                         primary_dxpl_id,
-                                                         secondary_dxpl_id,
-                                                         write_permitted,
-                                                         first_flush_ptr);
+                                                         write_permitted);
 
                         if ( result != SUCCEED ) {
 
@@ -6745,13 +5967,11 @@ done:
  */
 static herr_t
 H5C__autoadjust__ageout(H5F_t * f,
+                        hid_t dxpl_id,
                         double hit_rate,
                         enum H5C_resize_status * status_ptr,
                         size_t * new_max_cache_size_ptr,
-                        hid_t primary_dxpl_id,
-                        hid_t secondary_dxpl_id,
-                        hbool_t write_permitted,
-                        hbool_t * first_flush_ptr)
+                        hbool_t write_permitted)
 {
     H5C_t *     cache_ptr = f->shared->cache;
     herr_t	result;
@@ -6792,8 +6012,7 @@ H5C__autoadjust__ageout(H5F_t * f,
         if ( cache_ptr->max_cache_size > (cache_ptr->resize_ctl).min_size ){
 
             /* evict aged out cache entries if appropriate... */
-            if(H5C__autoadjust__ageout__evict_aged_out_entries(f, primary_dxpl_id,
-                    secondary_dxpl_id, write_permitted, first_flush_ptr) < 0)
+            if(H5C__autoadjust__ageout__evict_aged_out_entries(f, dxpl_id, write_permitted) < 0)
                 HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "error flushing aged out entries.")
 
             /* ... and then reduce cache size if appropriate */
@@ -6990,20 +6209,31 @@ done:
  *
  * Programmer:  John Mainzer, 11/22/04
  *
+ * Changes:	Modified function to detect deletions of entries
+ *              during a scan of the LRU, and where appropriate,
+ *              restart the scan to avoid proceeding with a next
+ *              entry that is no longer in the cache.
+ *
+ *              Note the absence of checks after flushes of clean
+ *              entries.  As a second entry can only be removed by
+ *              by a call to the pre_serialize or serialize callback
+ *              of the first, and as these callbacks will not be called
+ *              on clean entries, no checks are needed.
+ *
+ *                                              JRM -- 4/6/15
+ *
  *-------------------------------------------------------------------------
  */
 static herr_t
 H5C__autoadjust__ageout__evict_aged_out_entries(H5F_t * f,
-                                                hid_t   primary_dxpl_id,
-                                                hid_t   secondary_dxpl_id,
-                                                hbool_t write_permitted,
-                                                hbool_t * first_flush_ptr)
+                                                hid_t   dxpl_id,
+                                                hbool_t write_permitted)
 {
     H5C_t *		cache_ptr = f->shared->cache;
-    herr_t              result;
     size_t		eviction_size_limit;
     size_t		bytes_evicted = 0;
     hbool_t		prev_is_dirty = FALSE;
+    hbool_t             restart_scan;
     H5C_cache_entry_t * entry_ptr;
     H5C_cache_entry_t * next_ptr;
     H5C_cache_entry_t * prev_ptr;
@@ -7032,13 +6262,17 @@ H5C__autoadjust__ageout__evict_aged_out_entries(H5F_t * f,
 
     if ( write_permitted ) {
 
+        restart_scan = FALSE;
         entry_ptr = cache_ptr->LRU_tail_ptr;
 
         while ( ( entry_ptr != NULL ) &&
                 ( (entry_ptr->type)->id != H5C__EPOCH_MARKER_TYPE ) &&
                 ( bytes_evicted < eviction_size_limit ) )
         {
+            HDassert(entry_ptr->magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
             HDassert( ! (entry_ptr->is_protected) );
+            HDassert( ! (entry_ptr->is_read_only) );
+            HDassert( (entry_ptr->ro_ref_count) == 0 );
 
 	    next_ptr = entry_ptr->next;
             prev_ptr = entry_ptr->prev;
@@ -7050,59 +6284,53 @@ H5C__autoadjust__ageout__evict_aged_out_entries(H5F_t * f,
 
             if ( entry_ptr->is_dirty ) {
 
-                result = H5C_flush_single_entry(f,
-                                                primary_dxpl_id,
-                                                secondary_dxpl_id,
-                                                entry_ptr->type,
-                                                entry_ptr->addr,
-                                                H5C__NO_FLAGS_SET,
-                                                first_flush_ptr,
-                                                FALSE);
-            } else {
+                /* reset entries_removed_counter and
+                 * last_entry_removed_ptr prior to the call to
+                 * H5C__flush_single_entry() so that we can spot
+                 * unexpected removals of entries from the cache,
+                 * and set the restart_scan flag if proceeding
+                 * would be likely to cause us to scan an entry
+                 * that is no longer in the cache.
+                 */
+                cache_ptr->entries_removed_counter = 0;
+                cache_ptr->last_entry_removed_ptr  = NULL;
 
-                bytes_evicted += entry_ptr->size;
+                if(H5C__flush_single_entry(f, dxpl_id, entry_ptr, H5C__NO_FLAGS_SET, NULL) < 0)
+                    HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "unable to flush entry")
 
-                result = H5C_flush_single_entry(f,
-                                                primary_dxpl_id,
-                                                secondary_dxpl_id,
-                                                entry_ptr->type,
-                                                entry_ptr->addr,
-                                                H5C__FLUSH_INVALIDATE_FLAG,
-                                                first_flush_ptr,
-                                                TRUE);
-            }
+                if ( ( cache_ptr->entries_removed_counter > 1 ) ||
+                     ( cache_ptr->last_entry_removed_ptr == prev_ptr ) )
 
-            if ( result < 0 ) {
+                    restart_scan = TRUE;
 
-                HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, \
-                            "unable to flush entry")
+            } else {
+
+                bytes_evicted += entry_ptr->size;
+
+                if(H5C__flush_single_entry(f, dxpl_id, entry_ptr, H5C__FLUSH_INVALIDATE_FLAG | H5C__DEL_FROM_SLIST_ON_DESTROY_FLAG, NULL) < 0 )
+                    HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "unable to flush entry")
             }
 
             if ( prev_ptr != NULL ) {
-#ifndef NDEBUG
-                if ( prev_ptr->magic != H5C__H5C_CACHE_ENTRY_T_MAGIC ) {
 
-                    /* something horrible has happened to *prev_ptr --
-                     * scream and die.
-                     */
-                    HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, \
-                                "*prev_ptr corrupt")
-
-                } else
-#endif /* NDEBUG */
-		if ( ( prev_ptr->is_dirty != prev_is_dirty )
-                         ||
-                         ( prev_ptr->next != next_ptr )
-                         ||
-                         ( prev_ptr->is_protected )
-                         ||
-                         ( prev_ptr->is_pinned ) ) {
+		if ( ( restart_scan )
+                     ||
+                     ( prev_ptr->is_dirty != prev_is_dirty )
+                     ||
+                     ( prev_ptr->next != next_ptr )
+                     ||
+                     ( prev_ptr->is_protected )
+                     ||
+                     ( prev_ptr->is_pinned ) ) {
 
                     /* something has happened to the LRU -- start over
 		     * from the tail.
                      */
+                    restart_scan = FALSE;
                     entry_ptr = cache_ptr->LRU_tail_ptr;
 
+		    H5C__UPDATE_STATS_FOR_LRU_SCAN_RESTART(cache_ptr)
+
                 } else {
 
                     entry_ptr = prev_ptr;
@@ -7160,23 +6388,15 @@ H5C__autoadjust__ageout__evict_aged_out_entries(H5F_t * f,
 
             if ( ! (entry_ptr->is_dirty) ) {
 
-                result = H5C_flush_single_entry(f,
-                                                primary_dxpl_id,
-                                                secondary_dxpl_id,
-                                                entry_ptr->type,
-                                                entry_ptr->addr,
-                                                H5C__FLUSH_INVALIDATE_FLAG,
-                                                first_flush_ptr,
-                                                TRUE);
-
-                if ( result < 0 ) {
-
-                    HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, \
-                                "unable to flush clean entry")
-                }
+                if(H5C__flush_single_entry(f, dxpl_id, entry_ptr, H5C__FLUSH_INVALIDATE_FLAG | H5C__DEL_FROM_SLIST_ON_DESTROY_FLAG, NULL) < 0)
+                    HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "unable to flush clean entry")
             }
             /* just skip the entry if it is dirty, as we can't do
              * anything with it now since we can't write.
+	     *
+	     * Since all entries are clean, serialize() will not be called,
+	     * and thus we needn't test to see if the LRU has been changed
+	     * out from under us.
              */
 
             entry_ptr = prev_ptr;
@@ -7640,17 +6860,44 @@ done:
  * Programmer:  John Mainzer
  *		3/24/065
  *
+ * Changes:     Modified function to test for slist chamges in
+ *              pre_serialize and serialize callbacks, and re-start
+ *              scans through the slist when such changes occur.
+ *
+ *              This has been a potential problem for some time,
+ *              and there has been code in this function to deal
+ *              with elements of this issue.  However the shift
+ *              to the V3 cache in combination with the activities
+ *              of some of the cache clients (in particular the
+ *              free space manager and the fractal heap) have
+ *              made this re-work necessary in H5C_flush_cache.
+ *
+ *		At present, this issue doesn't seem to be causing problems
+ *		in H5C_flush_invalidate_cache().  However, it seems 
+ *		prudent to port the H5C_flush_cache changes to this 
+ *		function as well.
+ *
+ *                                              JRM -- 12/14/14
+ *
+ *		Added code to track entry size change during flush single
+ *		entry.  This didn't used to be a problem, as the entry 
+ *		was largely removed from the cache data structures before
+ *		the flush proper.  However, re-entrant calls to the cache
+ *		in the parallel case required a re-factoring of the 
+ *		H5C__flush_single_entry() function to keep entries fully
+ *		in the cache until after the pre-serialize and serialize
+ *		calls.
+ *                                               JRM -- 12/25/14
+ *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5C_flush_invalidate_cache(H5F_t * f,
-                           hid_t    primary_dxpl_id,
-                           hid_t    secondary_dxpl_id,
+H5C_flush_invalidate_cache(const H5F_t * f,
+                           hid_t    dxpl_id,
 			   unsigned flags)
 {
     H5C_t *		cache_ptr = f->shared->cache;
-    herr_t              status;
-    hbool_t		first_flush = TRUE;
+    hbool_t             restart_slist_scan;
     int32_t		protected_entries = 0;
     int32_t		i;
     int32_t		cur_pel_len;
@@ -7661,10 +6908,14 @@ H5C_flush_invalidate_cache(H5F_t * f,
     H5C_cache_entry_t *	entry_ptr = NULL;
     H5C_cache_entry_t *	next_entry_ptr = NULL;
 #if H5C_DO_SANITY_CHECKS
-    int64_t		actual_slist_len = 0;
+    int64_t		flushed_slist_len = 0;
     int64_t		initial_slist_len = 0;
-    size_t              actual_slist_size = 0;
+    int64_t             flushed_slist_size = 0;
     size_t              initial_slist_size = 0;
+    int64_t		entry_size_change;
+    int64_t	      * entry_size_change_ptr = &entry_size_change;
+#else /* H5C_DO_SANITY_CHECKS */
+    int64_t           * entry_size_change_ptr = NULL;
 #endif /* H5C_DO_SANITY_CHECKS */
     herr_t		ret_value = SUCCEED;
 
@@ -7681,16 +6932,9 @@ H5C_flush_invalidate_cache(H5F_t * f,
     cooked_flags = flags & H5C__FLUSH_CLEAR_ONLY_FLAG;
 
     /* remove ageout markers if present */
-    if ( cache_ptr->epoch_markers_active > 0 ) {
-
-        status = H5C__autoadjust__ageout__remove_all_markers(cache_ptr);
-
-        if ( status != SUCCEED ) {
-
-            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, \
-                        "error removing all epoch markers.")
-        }
-    }
+    if(cache_ptr->epoch_markers_active > 0)
+        if(H5C__autoadjust__ageout__remove_all_markers(cache_ptr) < 0)
+            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "error removing all epoch markers.")
 
     /* The flush proceedure here is a bit strange.
      *
@@ -7743,28 +6987,9 @@ H5C_flush_invalidate_cache(H5F_t * f,
              * may be created by the flush call backs.  Thus it is possible
              * that the slist will not be empty after we finish the scan.
              */
-            if ( cache_ptr->slist_len == 0 ) {
-
-                node_ptr = NULL;
-                HDassert( cache_ptr->slist_size == 0 );
-
-            } else {
-
-                /* Start at beginning of skip list each time */
-                node_ptr = H5SL_first(cache_ptr->slist_ptr);
-                HDassert( node_ptr != NULL );
-
-                /* Get cache entry for this node */
-                next_entry_ptr = (H5C_cache_entry_t *)H5SL_item(node_ptr);
-                if ( NULL == next_entry_ptr )
-                    HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "next_entry_ptr == NULL ?!?!")
-                HDassert( next_entry_ptr->magic == H5C__H5C_CACHE_ENTRY_T_MAGIC );
-                HDassert( next_entry_ptr->is_dirty );
-                HDassert( next_entry_ptr->in_slist );
-            }
 
 #if H5C_DO_SANITY_CHECKS
-            /* Depending on circumstances, H5C_flush_single_entry() will
+            /* Depending on circumstances, H5C__flush_single_entry() will
              * remove dirty entries from the slist as it flushes them.
              * Thus for sanity checks we must make note of the initial
              * slist length and size before we do any flushes.
@@ -7785,63 +7010,80 @@ H5C_flush_invalidate_cache(H5F_t * f,
             cache_ptr->slist_len_increase = 0;
             cache_ptr->slist_size_increase = 0;
 
-            /* Finally, reset the actual_slist_len and actual_slist_size
+            /* Finally, reset the flushed_slist_len and flushed_slist_size
              * fields to zero, as these fields are used to accumulate
              * the slist lenght and size that we see as we scan through
              * the slist.
              */
-            actual_slist_len = 0;
-            actual_slist_size = 0;
+            flushed_slist_len = 0;
+            flushed_slist_size = 0;
 #endif /* H5C_DO_SANITY_CHECKS */
 
-            while ( node_ptr != NULL )
+            /* set the cache_ptr->slist_change_in_pre_serialize and
+             * cache_ptr->slist_change_in_serialize to false.
+             *
+             * These flags are set to TRUE by H5C__flush_single_entry if the
+             * slist is modified by a pre_serialize or serialize call 
+             * respectively.
+             *
+             * H5C_flush_invalidate_cache() uses these flags to detect any 
+             * modifications to the slist that might corrupt the scan of 
+             * the slist -- and restart the scan in this event.
+             */
+            cache_ptr->slist_change_in_pre_serialize = FALSE;
+            cache_ptr->slist_change_in_serialize = FALSE;
+
+            /* this done, start the scan of the slist */
+
+            restart_slist_scan = TRUE;
+
+            while ( ( restart_slist_scan ) || ( node_ptr != NULL ) )
             {
-                entry_ptr = next_entry_ptr;
+                if ( restart_slist_scan )
+                {
+                    restart_slist_scan = FALSE;
 
-                /* With the advent of the fractal heap, it is possible
-                 * that the flush callback will dirty and/or resize
-                 * other entries in the cache.  In particular, while
-                 * Quincey has promised me that this will never happen,
-                 * it is possible that the flush callback for an
-                 * entry may protect an entry that is not in the cache,
-                 * perhaps causing the cache to flush and possibly
-                 * evict the entry associated with node_ptr to make
-                 * space for the new entry.
-                 *
-                 * Thus we do a bit of extra sanity checking on entry_ptr,
-                 * and break out of this scan of the skip list if we
-                 * detect major problems.  We have a bit of leaway on the
-                 * number of passes though the skip list, so this shouldn't
-                 * be an issue in the flush in and of itself, as it should
-                 * be all but impossible for this to happen more than once
-                 * in any flush.
-                 *
-                 * Observe that that breaking out of the scan early
-                 * shouldn't break the sanity checks just after the end
-                 * of this while loop.
-                 *
-                 * If an entry has merely been marked clean and removed from
-                 * the s-list, we simply break out of the scan.
-                 *
-                 * If the entry has been evicted, we flag an error and
-                 * exit.
-                 */
-#ifndef NDEBUG
-                if ( entry_ptr->magic != H5C__H5C_CACHE_ENTRY_T_MAGIC ) {
+                    /* Start at beginning of skip list */
+                    node_ptr = H5SL_first(cache_ptr->slist_ptr);
 
-                    HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "entry_ptr->magic is invalid ?!?!")
+                    if ( node_ptr == NULL )
+                    {
+                        /* the slist is empty -- break out of inner loop */
+                        break;
+                    }
+                    HDassert( node_ptr != NULL );
 
-                } else
-#endif /* NDEBUG */
-                if ( ( ! entry_ptr->is_dirty ) ||
-                     ( ! entry_ptr->in_slist ) ) {
+                    /* Get cache entry for this node */
+                    next_entry_ptr = (H5C_cache_entry_t *)H5SL_item(node_ptr);
 
-                    /* the s-list has been modified out from under us.
-                     * break out of the loop.
-                     */
-                    goto end_of_inner_loop;;
+                    if(NULL == next_entry_ptr)
+                        HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, \
+                                    "next_entry_ptr == NULL ?!?!")
+
+                    HDassert( next_entry_ptr->magic == \
+                              H5C__H5C_CACHE_ENTRY_T_MAGIC );
+                    HDassert( next_entry_ptr->is_dirty );
+                    HDassert( next_entry_ptr->in_slist );
                 }
 
+                entry_ptr = next_entry_ptr;
+
+                /* It is possible that entries will be dirtied, resized, 
+                 * flushed, or removed from the cache via the take ownership
+                 * flag as the result of pre_serialize or serialized callbacks. 
+                 * 
+                 * This in turn can corrupt the scan through the slist.
+                 *
+                 * We test for slist modifications in the pre_serialize 
+                 * and serialize callbacks, and restart the scan of the 
+                 * slist if we find them.  However, best we do some extra
+                 * sanity checking just in case.
+                 */
+
+                HDassert( entry_ptr->magic == H5C__H5C_CACHE_ENTRY_T_MAGIC );
+                HDassert( entry_ptr->in_slist );
+                HDassert( entry_ptr->is_dirty );
+
                 /* increment node pointer now, before we delete its target
                  * from the slist.
                  */
@@ -7854,6 +7096,7 @@ H5C_flush_invalidate_cache(H5F_t * f,
                     HDassert( next_entry_ptr->magic == H5C__H5C_CACHE_ENTRY_T_MAGIC );
                     HDassert( next_entry_ptr->is_dirty );
                     HDassert( next_entry_ptr->in_slist );
+                    HDassert( entry_ptr != next_entry_ptr );
                 } else {
                     next_entry_ptr = NULL;
 	        }
@@ -7877,21 +7120,6 @@ H5C_flush_invalidate_cache(H5F_t * f,
                        ( cache_ptr->num_last_entries >=
                          cache_ptr->slist_len ) ) ) {
 
-#if H5C_DO_SANITY_CHECKS
-                    /* update actual_slist_len & actual_slist_size before
-                     * the flush.  Note that the entry will be removed
-                     * from the slist after the flush, and thus may be
-                     * resized by the flush callback.  This is OK, as
-                     * we will catch the size delta in
-                     * cache_ptr->slist_size_increase.
-                     *
-                     * Note that we include pinned entries in this count, even
-                     * though we will not actually flush them.
-                     */
-                    actual_slist_len++;
-                    actual_slist_size += entry_ptr->size;
-#endif /* H5C_DO_SANITY_CHECKS */
-
                     if ( entry_ptr->is_protected ) {
 
                         /* we have major problems -- but lets flush
@@ -7903,28 +7131,52 @@ H5C_flush_invalidate_cache(H5F_t * f,
 
                         /* Test to see if we are can flush the entry now.
                          * If we can, go ahead and flush, but don't tell
-                         * H5C_flush_single_entry() to destroy the entry
+                         * H5C__flush_single_entry() to destroy the entry
                          * as pinned entries can't be evicted.
                          */
                         if(entry_ptr->flush_dep_height == curr_flush_dep_height ) {
-                            status = H5C_flush_single_entry(f,
-                                                            primary_dxpl_id,
-                                                            secondary_dxpl_id,
-                                                            NULL,
-                                                            entry_ptr->addr,
-                                                            H5C__NO_FLAGS_SET,
-                                                            &first_flush,
-                                                            FALSE);
-                            if ( status < 0 ) {
-
-                                /* This shouldn't happen -- if it does, we 
-                                 * are toast so just scream and die.
-                                 */
+#if H5C_DO_SANITY_CHECKS
+                            /* update flushed_slist_len & flushed_slist_size 
+                             * before the flush.  Note that the entry will 
+                             * be removed from the slist after the flush, 
+                             * and thus may be resized by the flush callback.
+                             * This is OK, as we will catch the size delta in
+                             * cache_ptr->slist_size_increase.
+                             *
+                             */
+                            flushed_slist_len++;
+                            flushed_slist_size += (int64_t)entry_ptr->size;
+		            entry_size_change = 0;
+#endif /* H5C_DO_SANITY_CHECKS */
+
+                            if(H5C__flush_single_entry(f, dxpl_id, entry_ptr, H5C__NO_FLAGS_SET, entry_size_change_ptr) < 0)
+                                HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "dirty pinned entry flush failed.")
+
+#if H5C_DO_SANITY_CHECKS
+                            /* entry size may have changed during the flush.
+                             * Update flushed_slist_size to account for this.
+                             */
+                            flushed_slist_size += entry_size_change;
+#endif /* H5C_DO_SANITY_CHECKS */
 
-                                HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, \
-                                            "dirty pinned entry flush failed.")
-                            } /* end if */
                             flushed_during_dep_loop = TRUE;
+
+                            if ( ( cache_ptr->slist_change_in_serialize ) ||
+                                 ( cache_ptr->slist_change_in_pre_serialize ) )
+                            {
+                                /* The slist has been modified by something
+                                 * other than the simple removal of the
+                                 * of the flushed entry after the flush.
+                                 *
+                                 * This has the potential to corrupt the
+                                 * scan through the slist, so restart it.
+                                 */
+                                restart_slist_scan = TRUE;
+                                cache_ptr->slist_change_in_pre_serialize 
+                                    = FALSE;
+                                cache_ptr->slist_change_in_serialize = FALSE;
+				H5C__UPDATE_STATS_FOR_SLIST_SCAN_RESTART(cache_ptr);
+                            }
                         } /* end if */
                         else if(entry_ptr->flush_dep_height < curr_flush_dep_height)
                             /* This shouldn't happen -- if it does, just scream and die.  */
@@ -7932,25 +7184,48 @@ H5C_flush_invalidate_cache(H5F_t * f,
                     } /* end if */
                     else {
                         if(entry_ptr->flush_dep_height == curr_flush_dep_height ){
+#if H5C_DO_SANITY_CHECKS
+                            /* update flushed_slist_len & flushed_slist_size 
+                             * before the flush.  Note that the entry will 
+                             * be removed from the slist after the flush, 
+                             * and thus may be resized by the flush callback.
+                             * This is OK, as we will catch the size delta in
+                             * cache_ptr->slist_size_increase.
+                             *
+                             */
+                            flushed_slist_len++;
+                            flushed_slist_size += (int64_t)entry_ptr->size;
+		            entry_size_change = 0;
+#endif /* H5C_DO_SANITY_CHECKS */
 
-                            status = H5C_flush_single_entry(f,
-                                                            primary_dxpl_id,
-                                                            secondary_dxpl_id,
-                                                            NULL,
-                                                            entry_ptr->addr,
-                                                            (cooked_flags | H5C__FLUSH_INVALIDATE_FLAG),
-                                                            &first_flush,
-                                                            TRUE);
-                            if ( status < 0 ) {
-
-                                /* This shouldn't happen -- if it does, we 
-                                 * are toast so just scream and die.
-                                 */
+                            if(H5C__flush_single_entry(f, dxpl_id, entry_ptr, (cooked_flags | H5C__FLUSH_INVALIDATE_FLAG | H5C__DEL_FROM_SLIST_ON_DESTROY_FLAG), entry_size_change_ptr) < 0)
+                                HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "dirty entry flush destroy failed.")
+
+#if H5C_DO_SANITY_CHECKS
+                            /* entry size may have changed during the flush.
+                             * Update flushed_slist_size to account for this.
+                             */
+                            flushed_slist_size += entry_size_change;
+#endif /* H5C_DO_SANITY_CHECKS */
 
-                                HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, \
-                                            "dirty entry flush destroy failed.")
-                            } /* end if */
                             flushed_during_dep_loop = TRUE;
+
+                            if ((cache_ptr->slist_change_in_serialize) ||
+                                (cache_ptr->slist_change_in_pre_serialize))
+                            {
+                                /* The slist has been modified by something
+                                 * other than the simple removal of the
+                                 * of the flushed entry after the flush.
+                                 *
+                                 * This has the potential to corrupt the
+                                 * scan through the slist, so restart it.
+                                 */
+                                restart_slist_scan = TRUE;
+                                cache_ptr->slist_change_in_pre_serialize
+                                    = FALSE;
+                                cache_ptr->slist_change_in_serialize = FALSE;
+				H5C__UPDATE_STATS_FOR_SLIST_SCAN_RESTART(cache_ptr)
+                            }
                         } /* end if */
                         else if(entry_ptr->flush_dep_height < curr_flush_dep_height)
                             /* This shouldn't happen -- if it does, just scream and die.  */
@@ -7971,11 +7246,10 @@ H5C_flush_invalidate_cache(H5F_t * f,
 
             if ( node_ptr == NULL ) {
 
-                HDassert( (actual_slist_len + cache_ptr->slist_len) ==
+                HDassert( (flushed_slist_len + cache_ptr->slist_len) ==
                           (initial_slist_len + cache_ptr->slist_len_increase) );
-                HDassert( (actual_slist_size + cache_ptr->slist_size) ==
-                          (initial_slist_size + 
-                           (size_t)(cache_ptr->slist_size_increase)) );
+                HDassert( (flushed_slist_size + (int64_t)cache_ptr->slist_size) ==
+                          ((int64_t)initial_slist_size + cache_ptr->slist_size_increase) );
             }
 #endif /* H5C_DO_SANITY_CHECKS */
 
@@ -7997,9 +7271,7 @@ H5C_flush_invalidate_cache(H5F_t * f,
                 while ( next_entry_ptr != NULL )
                 {
                     entry_ptr = next_entry_ptr;
-#ifndef NDEBUG
                     HDassert( entry_ptr->magic == H5C__H5C_CACHE_ENTRY_T_MAGIC );
-#endif /* NDEBUG */
 
                     next_entry_ptr = entry_ptr->ht_next;
                     HDassert ( ( next_entry_ptr == NULL ) ||
@@ -8028,23 +7300,46 @@ H5C_flush_invalidate_cache(H5F_t * f,
                              * If we can, go ahead and flush.
                              */
                             if(entry_ptr->flush_dep_height == curr_flush_dep_height ){
-                                status = H5C_flush_single_entry(f,
-                                                                primary_dxpl_id,
-                                                                secondary_dxpl_id,
-                                                                NULL,
-                                                                entry_ptr->addr,
-                                                                (cooked_flags | H5C__FLUSH_INVALIDATE_FLAG),
-                                                                &first_flush,
-                                                                TRUE);
-                                if ( status < 0 ) {
-
-                                    /* This shouldn't happen -- if it does, 
-                                     * we are toast so just scream and die.
-                                     */
+				/* if *entry_ptr is dirty, it is possible 
+                                 * that one or more other entries may be 
+                                 * either removed from the cache, loaded 
+                                 * into the cache, or moved to a new location
+                                 * in the file as a side effect of the flush.
+                                 *
+                                 * If this happens, and one of the target 
+                                 * entries happens to be the next entry in 
+                                 * the hash bucket, we could find ourselves 
+				 * either find ourselves either scanning a 
+                                 * non-existant entry, scanning through a 
+                                 * different bucket, or skipping an entry.
+                                 *
+                                 * Neither of these are good, so restart the 
+                                 * the scan at the head of the hash bucket 
+                                 * after the flush if *entry_ptr was dirty,
+                                 * on the off chance that the next entry was
+                                 * a target.
+                                 *
+                                 * This is not as inefficient at it might seem,
+                                 * as hash buckets typically have at most two
+                                 * or three entries.
+                                 */
+                                hbool_t entry_was_dirty;
+
+                                entry_was_dirty = entry_ptr->is_dirty;
 
-                                    HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, \
-                                                "Entry flush destroy failed.")
+                                if(H5C__flush_single_entry(f, dxpl_id, entry_ptr, (cooked_flags | H5C__FLUSH_INVALIDATE_FLAG | H5C__DEL_FROM_SLIST_ON_DESTROY_FLAG), NULL) < 0)
+                                    HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "Entry flush destroy failed.")
+
+				if ( entry_was_dirty ) {
+
+                                    /* update stats for hash bucket scan
+                                     * restart here.
+                                     *                   -- JRM 
+                                     */
+                                    next_entry_ptr = cache_ptr->index[i];
+				    H5C__UPDATE_STATS_FOR_HASH_BUCKET_SCAN_RESTART(cache_ptr)
                                 }
+
                                 flushed_during_dep_loop = TRUE;
                             } /* end if */
                             else if(entry_ptr->flush_dep_height < curr_flush_dep_height)
@@ -8060,7 +7355,7 @@ H5C_flush_invalidate_cache(H5F_t * f,
                      * of pinned entries from pass to pass.  If it stops
                      * shrinking before it hits zero, we scream and die.
                      */
-                    /* if the flush function on the entry we last evicted
+                    /* if the serialize function on the entry we last evicted
                      * loaded an entry into cache (as Quincey has promised me
                      * it never will), and if the cache was full, it is
                      * possible that *next_entry_ptr was flushed or evicted.
@@ -8069,8 +7364,13 @@ H5C_flush_invalidate_cache(H5F_t * f,
                      * test is triggred, we are accessing a deallocated piece
                      * of dynamically allocated memory, so we just scream and
                      * die.
+                     *
+                     * Update: The code to restart the scan after flushes
+                     *         of dirty entries should make it impossible 
+                     *         to satisfy the following test.  Leave it in
+                     *         in case I am wrong.
+                     *                                    -- JRM
                      */
-#ifndef NDEBUG
                     if ( ( next_entry_ptr != NULL ) &&
                          ( next_entry_ptr->magic !=
                            H5C__H5C_CACHE_ENTRY_T_MAGIC ) ) {
@@ -8081,7 +7381,6 @@ H5C_flush_invalidate_cache(H5F_t * f,
                         HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, \
                                     "next_entry_ptr->magic is invalid?!?!?.")
                     }
-#endif /* NDEBUG */
                 } /* end while loop scanning hash table bin */
             } /* end for loop scanning hash table */
 
@@ -8099,7 +7398,6 @@ H5C_flush_invalidate_cache(H5F_t * f,
                 curr_flush_dep_height++;
 
         } /* end while loop over flush dependency heights */
-end_of_inner_loop:
 
 	old_pel_len = cur_pel_len;
 	cur_pel_len = cache_ptr->pel_len;
@@ -8167,7 +7465,7 @@ done:
 
 /*-------------------------------------------------------------------------
  *
- * Function:    H5C_flush_single_entry
+ * Function:    H5C__flush_single_entry
  *
  * Purpose:     Flush or clear (and evict if requested) the cache entry
  *		with the specified address and type.  If the type is NULL,
@@ -8177,22 +7475,9 @@ done:
  *		Attempts to flush a protected entry will result in an
  *		error.
  *
- *		*first_flush_ptr should be true if only one
- *		flush is contemplated before the next load, or if this
- *		is the first of a sequence of flushes that will be
- *		completed before the next load.  *first_flush_ptr is set
- *		to false if a flush actually takes place, and should be
- *		left false until the end of the sequence.
- *
- *		The primary_dxpl_id is used if *first_flush_ptr is TRUE
- *		on entry, and a flush actually takes place.  The
- *		secondary_dxpl_id is used in any subsequent flush where
- *		*first_flush_ptr is FALSE on entry.
- *
  *		If the H5C__FLUSH_INVALIDATE_FLAG flag is set, the entry will
- *		be cleared and not flushed -- in the case *first_flush_ptr,
- *		primary_dxpl_id, and secondary_dxpl_id are all irrelevent,
- *		and the call can't be part of a sequence of flushes.
+ *		be cleared and not flushed, and the call can't be part of a
+ *              sequence of flushes.
  *
  *		If the caller knows the address of the skip list node at
  *		which the target entry resides, it can avoid a lookup
@@ -8209,41 +7494,73 @@ done:
  *
  * Programmer:  John Mainzer, 5/5/04
  *
+ * Changes:	Refactored function to remove the type_ptr parameter.
+ *
+ *						JRM -- 8/7/14
+ *
+ *              Added code to check for slist changes in pre_serialize and
+ *              serialize calls, and set 
+ *              cache_ptr->slist_change_in_pre_serialize and 
+ *		cache_ptr->slist_change_in_serialize as appropriate.
+ *
+ *                                              JRM -- 12/13/14
+ *
+ *		Refactored function to delay all modifications of the 
+ *		metadata cache data structures until after any calls 
+ *		to the pre-serialize or serialize callbacks.  
+ *
+ *		Need to do this, as some pre-serialize or serialize 
+ *		calls result in calls to the metadata cache and 
+ *		modifications to its data structures.  Thus, at the
+ *		time of any such call, the target entry flags and 
+ *		the metadata cache must all be consistant.
+ *
+ *		Also added the entry_size_change_ptr parameter, which 
+ *              allows the function to report back any change in the size 
+ *		of the entry during the flush.  Such size changes may 
+ *		occur during the pre-serialize callback.
+ *
+ *						JRM -- 12/24/14
+ *
  *-------------------------------------------------------------------------
  */
-static herr_t
-H5C_flush_single_entry(H5F_t *	   	   f,
-                       hid_t 		   primary_dxpl_id,
-                       hid_t 		   secondary_dxpl_id,
-                       const H5C_class_t * type_ptr,
-                       haddr_t		   addr,
-                       unsigned	     	   flags,
-                       hbool_t *	   first_flush_ptr,
-                       hbool_t		   del_entry_from_slist_on_destroy)
+herr_t
+H5C__flush_single_entry(const H5F_t *f, hid_t dxpl_id, H5C_cache_entry_t *entry_ptr,
+    unsigned flags, int64_t *entry_size_change_ptr)
 {
-    H5C_t *	     	cache_ptr = f->shared->cache;
+    H5C_t *	     	cache_ptr;              /* Cache for file */
     hbool_t		destroy;		/* external flag */
     hbool_t		clear_only;		/* external flag */
+    hbool_t		free_file_space;	/* external flag */
     hbool_t		take_ownership;		/* external flag */
+    hbool_t             del_from_slist_on_destroy;    /* external flag */
+    hbool_t		write_entry;		/* internal flag */
+    hbool_t		destroy_entry;		/* internal flag */
     hbool_t		was_dirty;
-    hbool_t		destroy_entry;
-    herr_t		status;
-    unsigned		flush_flags = H5C_CALLBACK__NO_FLAGS_SET;
-    H5C_cache_entry_t * entry_ptr = NULL;
+    haddr_t		new_addr = HADDR_UNDEF;
+    haddr_t		old_addr = HADDR_UNDEF;
+    size_t		new_len = 0;
+    size_t		new_compressed_len = 0;
     herr_t		ret_value = SUCCEED;      /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_PACKAGE
 
-    HDassert( f );
-    HDassert( cache_ptr );
-    HDassert( cache_ptr->magic == H5C__H5C_T_MAGIC );
-    HDassert( H5F_addr_defined(addr) );
-    HDassert( first_flush_ptr );
+    HDassert(f);
+    cache_ptr = f->shared->cache;
+    HDassert(cache_ptr);
+    HDassert(cache_ptr->magic == H5C__H5C_T_MAGIC);
+    HDassert(entry_ptr);
+
+    /* If defined, initialize *entry_size_change_ptr to 0 */
+    if(entry_size_change_ptr != NULL)
+        *entry_size_change_ptr = 0;
 
     /* setup external flags from the flags parameter */
     destroy                = ((flags & H5C__FLUSH_INVALIDATE_FLAG) != 0);
     clear_only             = ((flags & H5C__FLUSH_CLEAR_ONLY_FLAG) != 0);
+    free_file_space        = ((flags & H5C__FREE_FILE_SPACE_FLAG) != 0);
     take_ownership         = ((flags & H5C__TAKE_OWNERSHIP_FLAG) != 0);
+    del_from_slist_on_destroy = ((flags & H5C__DEL_FROM_SLIST_ON_DESTROY_FLAG) != 0);
 
     /* Set the flag for destroying the entry, based on the 'take ownership'
      * and 'destroy' flags
@@ -8253,363 +7570,592 @@ H5C_flush_single_entry(H5F_t *	   	   f,
     else
         destroy_entry = destroy;
 
-    /* attempt to find the target entry in the hash table */
-    H5C__SEARCH_INDEX(cache_ptr, addr, entry_ptr, FAIL)
+    /* we will write the entry to disk if it exists, is dirty, and if the 
+     * clear only flag is not set.
+     */
+    if(entry_ptr->is_dirty && !clear_only)
+        write_entry = TRUE;
+    else
+        write_entry = FALSE;
 
     /* run initial sanity checks */
 #if H5C_DO_SANITY_CHECKS
-    if ( entry_ptr != NULL ) {
+    HDassert( ! ( destroy && entry_ptr->is_pinned ) );
 
-        HDassert( ! ( ( destroy ) && ( entry_ptr->is_pinned ) ) );
+    if(entry_ptr->in_slist) {
+        HDassert(entry_ptr->is_dirty);
 
-        if ( entry_ptr->in_slist ) {
-
-            if ( ( ( entry_ptr->flush_marker ) && ( ! entry_ptr->is_dirty ) ) ||
-                 ( entry_ptr->addr != addr ) ) {
-
-                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, \
-                            "entry in slist failed sanity checks.")
-            }
-        } else {
-
-            if ( ( entry_ptr->is_dirty ) ||
-                 ( entry_ptr->flush_marker ) ||
-                 ( entry_ptr->addr != addr ) ) {
+        if((entry_ptr->flush_marker) && (!entry_ptr->is_dirty))
+            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "entry in slist failed sanity checks.")
+    } else {
+        HDassert(!entry_ptr->is_dirty);
+        HDassert(!entry_ptr->flush_marker);
 
-                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, \
-                            "entry failed sanity checks.")
-            }
-        }
+        if((entry_ptr->is_dirty) || (entry_ptr->flush_marker))
+            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "entry failed sanity checks.")
     }
 #endif /* H5C_DO_SANITY_CHECKS */
 
-    if ( ( entry_ptr != NULL ) && ( entry_ptr->is_protected ) )
-    {
+    if(entry_ptr->is_protected) {
+	HDassert(!entry_ptr->is_protected);
 
         /* Attempt to flush a protected entry -- scream and die. */
-        HGOTO_ERROR(H5E_CACHE, H5E_PROTECT, FAIL, \
-                    "Attempt to flush a protected entry.")
-    }
+        HGOTO_ERROR(H5E_CACHE, H5E_PROTECT, FAIL, "Attempt to flush a protected entry.")
+    } /* end if */
 
-    if ( ( entry_ptr != NULL ) &&
-         ( ( type_ptr == NULL ) || ( type_ptr->id == entry_ptr->type->id ) ) )
-    {
-        /* we have work to do */
+    /* set entry_ptr->flush_in_progress = TRUE and set
+     * entry_ptr->flush_marker = FALSE
+     *
+     * in the parallel case, do some sanity checking in passing.
+     */
+    HDassert(entry_ptr->type);
 
-	/* We will set flush_in_progress back to FALSE at the end if the
-	 * entry still exists at that point.
-	 */
-	entry_ptr->flush_in_progress = TRUE;
+    was_dirty = entry_ptr->is_dirty;  /* needed later for logging */
+
+    /* We will set flush_in_progress back to FALSE at the end if the
+     * entry still exists at that point.
+     */
+    entry_ptr->flush_in_progress = TRUE;
+    entry_ptr->flush_marker = FALSE;
 
 #ifdef H5_HAVE_PARALLEL
 #ifndef NDEBUG
-        /* If MPI based VFD is used, do special parallel I/O sanity checks.
-         * Note that we only do these sanity checks when the clear_only flag
-         * is not set, and the entry to be flushed is dirty.  Don't bother
-         * otherwise as no file I/O can result.
-         */
-        if(!clear_only && entry_ptr->is_dirty &&
-                H5F_HAS_FEATURE(f, H5FD_FEAT_HAS_MPI)) {
-            H5P_genplist_t *dxpl;       /* Dataset transfer property list */
-            unsigned coll_meta;         /* Collective metadata write flag */
+    /* If MPI based VFD is used, do special parallel I/O sanity checks.
+     * Note that we only do these sanity checks when the clear_only flag
+     * is not set, and the entry to be flushed is dirty.  Don't bother
+     * otherwise as no file I/O can result.
+     */
+    if(!clear_only && entry_ptr->is_dirty && H5F_HAS_FEATURE(f, H5FD_FEAT_HAS_MPI)) {
+        H5P_genplist_t *dxpl;       /* Dataset transfer property list */
+        unsigned coll_meta;         /* Collective metadata write flag */
 
-            /* Get the dataset transfer property list */
-            if(NULL == (dxpl = H5I_object(primary_dxpl_id)))
-                HGOTO_ERROR(H5E_CACHE, H5E_BADTYPE, FAIL, "not a dataset transfer property list")
+        /* Get the dataset transfer property list */
+        if(NULL == (dxpl = H5I_object(dxpl_id)))
+            HGOTO_ERROR(H5E_CACHE, H5E_BADTYPE, FAIL, "not a dataset transfer property list")
 
-            /* Get the collective metadata write property */
-            if(H5P_get(dxpl, H5AC_COLLECTIVE_META_WRITE_NAME, &coll_meta) < 0)
-                HGOTO_ERROR(H5E_CACHE, H5E_CANTGET, FAIL, "can't retrieve xfer mode")
+        /* Get the collective metadata write property */
+        if(H5P_get(dxpl, H5AC_COLLECTIVE_META_WRITE_NAME, &coll_meta) < 0)
+            HGOTO_ERROR(H5E_CACHE, H5E_CANTGET, FAIL, "can't retrieve xfer mode")
 
-            /* Sanity check collective metadata write flag */
-            HDassert(coll_meta);
-        } /* end if */
+        /* Sanity check collective metadata write flag */
+        HDassert(coll_meta);
+    } /* end if */
 #endif /* NDEBUG */
 #endif /* H5_HAVE_PARALLEL */
 
-        was_dirty = entry_ptr->is_dirty;
+    /* serialize the entry if necessary, and then write it to disk. */
+    if(write_entry) {
+        unsigned serialize_flags = H5C__SERIALIZE_NO_FLAGS_SET;
 
-        entry_ptr->flush_marker = FALSE;
+	/* The entry is dirty, and we are doing either a flush,
+	 * or a flush destroy.  In either case, serialize the
+	 * entry and write it to disk.
+         *
+         * Note that this may cause the entry to be re-sized and/or
+         * moved in the cache.  
+	 *
+         * As we will not update the metadata cache's data structures 
+         * until we we finish the write, we must touch up these 
+         * data structures for size and location changes even if we 
+         * are about to delete the entry from the cache (i.e. on a 
+         * flush destroy).
+         */
+        HDassert(entry_ptr->is_dirty);
 
-        if ( clear_only ) {
-            H5C__UPDATE_STATS_FOR_CLEAR(cache_ptr, entry_ptr)
-        } else {
-            H5C__UPDATE_STATS_FOR_FLUSH(cache_ptr, entry_ptr)
-        }
+#if H5C_DO_SANITY_CHECKS
+        if(cache_ptr->check_write_permitted && !(cache_ptr->write_permitted))
+            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Write when writes are always forbidden!?!?!")
+#endif /* H5C_DO_SANITY_CHECKS */
 
-        if ( destroy ) {
-            H5C__UPDATE_STATS_FOR_EVICTION(cache_ptr, entry_ptr)
-        }
+        if(NULL == entry_ptr->image_ptr) {
+            size_t image_size;
 
-        /* If the entry's type has a 'notify' callback and the entry is about
-         * to be removed from the cache, send a 'before eviction' notice while
-         * the entry is still fully integrated in the cache.
-         */
-        if(destroy) {
-            if(entry_ptr->type->notify &&
-                    (entry_ptr->type->notify)(H5C_NOTIFY_ACTION_BEFORE_EVICT, entry_ptr) < 0)
-                HGOTO_ERROR(H5E_CACHE, H5E_CANTNOTIFY, FAIL, "can't notify client about entry to evict")
+            if(entry_ptr->compressed)
+                image_size = entry_ptr->compressed_size;
+            else
+                image_size = entry_ptr->size;
+            HDassert(image_size > 0);
+
+
+            if(NULL == (entry_ptr->image_ptr = H5MM_malloc(image_size + H5C_IMAGE_EXTRA_SPACE)))
+                HGOTO_ERROR(H5E_CACHE, H5E_CANTALLOC, FAIL, "memory allocation failed for on disk image buffer")
+#if H5C_DO_MEMORY_SANITY_CHECKS
+            HDmemcpy(((uint8_t *)entry_ptr->image_ptr) + image_size, H5C_IMAGE_SANITY_VALUE, H5C_IMAGE_EXTRA_SPACE);
+#endif /* H5C_DO_MEMORY_SANITY_CHECKS */
         } /* end if */
 
-        /* Always remove the entry from the hash table on a destroy.  On a
-         * flush with destroy, it is cheaper to discard the skip list all at
-         * once rather than remove the entries one by one, so we only delete
-         * from the slist only if requested.
-         *
-         * We must do deletions now as the callback routines will free the
-         * entry if destroy is true.
-	 *
-	 * Note that it is possible that the entry will be moved during
-	 * its call to flush.  This will upset H5C_move_entry() if we
-	 * don't tell it that it doesn't have to worry about updating the
-	 * index and SLIST.  Use the destroy_in_progress field for this
-	 * purpose.
-         */
-        if ( destroy ) {
+        if(!(entry_ptr->image_up_to_date)) {
+            /* reset cache_ptr->slist_changed so we can detect slist
+             * modifications in the pre_serialize call.
+             */
+            cache_ptr->slist_changed = FALSE;
+
+            /* make note of the entry's current address */
+            old_addr = entry_ptr->addr;
+
+            /* Call client's pre-serialize callback, if there's one */
+            if ( ( entry_ptr->type->pre_serialize != NULL ) && 
+                 ( (entry_ptr->type->pre_serialize)(f, dxpl_id, 
+                                                    (void *)entry_ptr,
+                                                    entry_ptr->addr, 
+                                                    entry_ptr->size,
+						    entry_ptr->compressed_size,
+                                                    &new_addr, &new_len, 
+                                                    &new_compressed_len,
+                                                    &serialize_flags) < 0 ) )
+                HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "unable to pre-serialize entry")
+
+            /* set cache_ptr->slist_change_in_pre_serialize if the 
+             * slist was modified.
+             */
+            if(cache_ptr->slist_changed)
+                cache_ptr->slist_change_in_pre_serialize = TRUE;
+
+            /* Check for any flags set in the pre-serialize callback */
+            if(serialize_flags != H5C__SERIALIZE_NO_FLAGS_SET) {
+                /* Check for unexpected flags from serialize callback */
+                if(serialize_flags & ~(H5C__SERIALIZE_RESIZED_FLAG | 
+                                       H5C__SERIALIZE_MOVED_FLAG |
+                                       H5C__SERIALIZE_COMPRESSED_FLAG))
+                    HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "unknown serialize flag(s)")
+#ifdef H5_HAVE_PARALLEL
+                /* In the parallel case, resizes and moves in
+                 * the serialize operation can cause problems.
+                 * If they occur, scream and die.
+                 *
+                 * At present, in the parallel case, the aux_ptr
+                 * will only be set if there is more than one
+                 * process.  Thus we can use this to detect
+                 * the parallel case.
+                 *
+                 * This works for now, but if we start using the
+                 * aux_ptr for other purposes, we will have to
+                 * change this test accordingly.
+                 *
+                 * NB: While this test detects entryies that attempt
+                 *     to resize or move themselves during a flush
+                 *     in the parallel case, it will not detect an
+                 *     entry that dirties, resizes, and/or moves
+                 *     other entries during its flush.
+                 *
+                 *     From what Quincey tells me, this test is
+                 *     sufficient for now, as any flush routine that
+                 *     does the latter will also do the former.
+                 *
+                 *     If that ceases to be the case, further
+                 *     tests will be necessary.
+                 */
+                if(cache_ptr->aux_ptr != NULL)
+                    HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "resize/move in serialize occured in parallel case.")
+#endif /* H5_HAVE_PARALLEL */
 
-            entry_ptr->destroy_in_progress = TRUE;
+                /* Resize the buffer if required */
+                if ( ( ( ! entry_ptr->compressed ) &&
+                       ( serialize_flags & H5C__SERIALIZE_RESIZED_FLAG ) ) ||
+                     ( ( entry_ptr->compressed ) &&
+                       ( serialize_flags & H5C__SERIALIZE_COMPRESSED_FLAG ) ) )
+                {
+                    size_t new_image_size;
+
+            	    if(entry_ptr->compressed)
+                        new_image_size = new_compressed_len;
+                    else
+                        new_image_size = new_len;
+                    HDassert(new_image_size > 0);
+
+                    /* Release the current image */
+                    if(entry_ptr->image_ptr)
+                        entry_ptr->image_ptr = H5MM_xfree(entry_ptr->image_ptr);
+
+                    /* Allocate a new image buffer */
+                    if(NULL == (entry_ptr->image_ptr = H5MM_malloc(new_image_size + H5C_IMAGE_EXTRA_SPACE)))
+                        HGOTO_ERROR(H5E_CACHE, H5E_CANTALLOC, FAIL, "memory allocation failed for on disk image buffer")
+#if H5C_DO_MEMORY_SANITY_CHECKS
+                    HDmemcpy(((uint8_t *)entry_ptr->image_ptr) + new_image_size, H5C_IMAGE_SANITY_VALUE, H5C_IMAGE_EXTRA_SPACE);
+#endif /* H5C_DO_MEMORY_SANITY_CHECKS */
+                } /* end if */
 
-            H5C__DELETE_FROM_INDEX(cache_ptr, entry_ptr)
+		/* If required, update the entry and the cache data structures
+                 * for a resize.
+		 */
+                if(serialize_flags & H5C__SERIALIZE_RESIZED_FLAG) {
+                    H5C__UPDATE_STATS_FOR_ENTRY_SIZE_CHANGE(cache_ptr, \
+                                                            entry_ptr, new_len)
+
+                    /* update the hash table for the size change*/
+                    H5C__UPDATE_INDEX_FOR_SIZE_CHANGE(cache_ptr, \
+                                                      entry_ptr->size, \
+                                                      new_len, entry_ptr, \
+                                                      !(entry_ptr->is_dirty));
+
+                    /* The entry can't be protected since we are
+                     * in the process of flushing it.  Thus we must
+                     * update the replacement policy data
+                     * structures for the size change.  The macro
+                     * deals with the pinned case.
+                     */
+                    H5C__UPDATE_RP_FOR_SIZE_CHANGE(cache_ptr, entry_ptr, new_len);
 
-            if ( ( entry_ptr->in_slist ) &&
-                 ( del_entry_from_slist_on_destroy ) ) {
+                    /* as we haven't updated the cache data structures for 
+                     * for the flush or flush destroy yet, the entry should
+                     * be in the slist.  Thus update it for the size change.
+                     */
+		    HDassert(entry_ptr->in_slist);
+                    H5C__UPDATE_SLIST_FOR_SIZE_CHANGE(cache_ptr, entry_ptr->size, \
+                                                      new_len)
 
-                H5C__REMOVE_ENTRY_FROM_SLIST(cache_ptr, entry_ptr)
-            }
-        }
+		    /* if defined, update *entry_size_change_ptr for the 
+                     * change in entry size.
+                     */
+                    if(entry_size_change_ptr != NULL)
+                        *entry_size_change_ptr = (int64_t)new_len - (int64_t)(entry_ptr->size);
 
-        /* Update the replacement policy for the flush or eviction.
-         * Again, do this now so we don't have to reference freed
-         * memory in the destroy case.
-         */
-        if ( destroy ) { /* AKA eviction */
+                    /* finally, update the entry for its new size */
+                    entry_ptr->size = new_len;
+                } /* end if */
 
-            H5C__UPDATE_RP_FOR_EVICTION(cache_ptr, entry_ptr, FAIL)
+                /* If required, udate the entry and the cache data structures 
+                 * for a move 
+                 */
+                if(serialize_flags & H5C__SERIALIZE_MOVED_FLAG) {
+#if H5C_DO_SANITY_CHECKS
+                    int64_t saved_slist_len_increase;
+                    int64_t saved_slist_size_increase;
+#endif /* H5C_DO_SANITY_CHECKS */
 
-        } else {
+                    H5C__UPDATE_STATS_FOR_MOVE(cache_ptr, entry_ptr)
 
-            H5C__UPDATE_RP_FOR_FLUSH(cache_ptr, entry_ptr, FAIL)
-        }
+                    if(entry_ptr->addr == old_addr) {
+                        /* we must update cache data structures for the 
+                         * change in address.
+                         */
 
-        /* Clear the dirty flag only, if requested */
-        if ( clear_only ) {
+                        /* delete the entry from the hash table and the slist */
+                        H5C__DELETE_FROM_INDEX(cache_ptr, entry_ptr)
+                        H5C__REMOVE_ENTRY_FROM_SLIST(cache_ptr, entry_ptr)
 
-	    if ( destroy ) {
-#ifndef NDEBUG
-		/* we are about to call the clear callback with the
-		 * destroy flag set -- this will result in *entry_ptr
-		 * being freed.  Set the magic field to bad magic
-		 * so we can detect a freed cache entry if we see
-		 * one.
-		 */
-		entry_ptr->magic = H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC;
-#endif /* NDEBUG */
-                entry_ptr->cache_ptr = NULL;
-	    }
-            /* Call the callback routine to clear all dirty flags for object */
-            if ( (entry_ptr->type->clear)(f, entry_ptr, destroy_entry) < 0 ) {
+		        /* update the entry for its new address */
+                        entry_ptr->addr = new_addr;
 
-                HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "can't clear entry")
-            }
-        } else {
+		        /* and then reinsert in the index and slist */
+                        H5C__INSERT_IN_INDEX(cache_ptr, entry_ptr, FAIL)
 
 #if H5C_DO_SANITY_CHECKS
-            if ( ( entry_ptr->is_dirty ) &&
-                 ( cache_ptr->check_write_permitted == NULL ) &&
-                 ( ! (cache_ptr->write_permitted) ) )
+		        /* save cache_ptr->slist_len_increase and 
+                         * cache_ptr->slist_size_increase before the 
+                         * reinsertion into the slist, and restore 
+                         * them afterwards to avoid skewing our sanity
+                         * checking.
+                         */
+                        saved_slist_len_increase = cache_ptr->slist_len_increase;
+                        saved_slist_size_increase = cache_ptr->slist_size_increase;
+#endif /* H5C_DO_SANITY_CHECKS */
 
-                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, \
-                            "Write when writes are always forbidden!?!?!")
+                        H5C__INSERT_ENTRY_IN_SLIST(cache_ptr, entry_ptr, FAIL)
+
+#if H5C_DO_SANITY_CHECKS
+                        cache_ptr->slist_len_increase = saved_slist_len_increase;
+                        cache_ptr->slist_size_increase = saved_slist_size_increase;
 #endif /* H5C_DO_SANITY_CHECKS */
+                    }
+                    else /* move is alread done for us -- just do sanity checks */
+                        HDassert(entry_ptr->addr == new_addr);
+                } /* end if */
 
-	    if ( destroy ) {
-#ifndef NDEBUG
-	        /* we are about to call the flush callback with the
-	         * destroy flag set -- this will result in *entry_ptr
-	         * being freed.  Set the magic field to bad magic
-	         * so we can detect a freed cache entry if we see
-	         * one.
-	         */
-	        entry_ptr->magic = H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC;
-#endif /* NDEBUG */
-                entry_ptr->cache_ptr = NULL;
-	    }
+                if(serialize_flags & H5C__SERIALIZE_COMPRESSED_FLAG) {
+		    /* just save the new compressed entry size in 
+                     * entry_ptr->compressed_size.  We don't need to 
+ 		     * do more, as compressed size is only used for I/O.
+                     */
+                    HDassert(entry_ptr->compressed);
+                    entry_ptr->compressed_size = new_compressed_len;
+                }
+            } /* end if ( serialize_flags != H5C__SERIALIZE_NO_FLAGS_SET ) */
 
-            /* Only block for all the processes on the first piece of metadata
-             */
+            /* Serialize object into buffer */
+            {
+                size_t image_len;
 
-            if ( *first_flush_ptr && entry_ptr->is_dirty ) {
+                if(entry_ptr->compressed)
+                    image_len = entry_ptr->compressed_size;
+                else
+                    image_len = entry_ptr->size;
 
-                status = (entry_ptr->type->flush)(f, primary_dxpl_id, destroy_entry,
-                                                 entry_ptr->addr, entry_ptr,
-						 &flush_flags);
-                *first_flush_ptr = FALSE;
+                /* reset cache_ptr->slist_changed so we can detect slist
+                 * modifications in the serialize call.
+                 */
+                cache_ptr->slist_changed = FALSE;
 
-            } else {
+            
+                if(entry_ptr->type->serialize(f, entry_ptr->image_ptr, 
+                                                image_len, (void *)entry_ptr) < 0)
+                    HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "unable to serialize entry")
 
-                status = (entry_ptr->type->flush)(f, secondary_dxpl_id,
-                                                 destroy_entry, entry_ptr->addr,
-                                                 entry_ptr, &flush_flags);
-            }
+                /* set cache_ptr->slist_change_in_serialize if the 
+                 * slist was modified.
+                 */
+                if(cache_ptr->slist_changed)
+                    cache_ptr->slist_change_in_pre_serialize = TRUE;
 
-            if ( status < 0 ) {
+#if H5C_DO_MEMORY_SANITY_CHECKS
+                HDassert(0 == HDmemcmp(((uint8_t *)entry_ptr->image_ptr) + image_len, 
+                                       H5C_IMAGE_SANITY_VALUE, H5C_IMAGE_EXTRA_SPACE));
+#endif /* H5C_DO_MEMORY_SANITY_CHECKS */
 
-                HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, \
-                            "unable to flush entry")
+                entry_ptr->image_up_to_date = TRUE;
             }
+        } /* end if ( ! (entry_ptr->image_up_to_date) ) */
+
+        /* Finally, write the image to disk.  
+         * 
+         * Note that if either the H5C__CLASS_NO_IO_FLAG or the 
+         * the H5AC__CLASS_SKIP_WRITES flag is set in the 
+         * in the entry's type, we silently skip the write.  This
+         * flag should only be used in test code. 
+         */
+        if ( ( ((entry_ptr->type->flags) & H5C__CLASS_NO_IO_FLAG) == 0 ) &&
+             ( ((entry_ptr->type->flags) & H5C__CLASS_SKIP_WRITES) == 0 ) )
+        {
+	    /* If compression is not enabled, the size of the entry on 
+             * disk is entry_prt->size.  However if entry_ptr->compressed
+             * is TRUE, the on disk size is entry_ptr->compressed_size.
+             */
+            size_t image_size;
 
-#ifdef H5_HAVE_PARALLEL
-            if ( flush_flags != H5C_CALLBACK__NO_FLAGS_SET ) {
-
-                /* In the parallel case, flush operations can
-		 * cause problems.  If they occur, scream and
-		 * die.
-		 *
-		 * At present, in the parallel case, the aux_ptr
-		 * will only be set if there is more than one
-		 * process.  Thus we can use this to detect
-		 * the parallel case.
-		 *
-		 * This works for now, but if we start using the
-		 * aux_ptr for other purposes, we will have to
-		 * change this test accordingly.
-		 *
-		 * NB: While this test detects entryies that attempt
-		 *     to resize or move themselves during a flush
-		 *     in the parallel case, it will not detect an
-		 *     entry that dirties, resizes, and/or moves
-		 *     other entries during its flush.
-		 *
-		 *     From what Quincey tells me, this test is
-		 *     sufficient for now, as any flush routine that
-		 *     does the latter will also do the former.
-		 *
-		 *     If that ceases to be the case, further
-		 *     tests will be necessary.
-		 */
-		if ( cache_ptr->aux_ptr != NULL )
-
-                    HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, \
-		        "resize/move in serialize occured in parallel case.")
+            if(entry_ptr->compressed)
+                image_size = entry_ptr->compressed_size;
+            else
+                image_size = entry_ptr->size;
 
-	    }
-#endif /* H5_HAVE_PARALLEL */
+            if(H5F_block_write(f, entry_ptr->type->mem_type, entry_ptr->addr,
+                    image_size, dxpl_id, entry_ptr->image_ptr) < 0)
+                HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "Can't write image to file.")
         }
 
-        if ( ( ! destroy ) && ( entry_ptr->in_slist ) ) {
+        /* if the entry has a notify callback, notify it that we have 
+         * just flushed the entry.
+         */
+        if(entry_ptr->type->notify &&
+             (entry_ptr->type->notify)(H5C_NOTIFY_ACTION_AFTER_FLUSH, entry_ptr) < 0 )
+            HGOTO_ERROR(H5E_CACHE, H5E_CANTNOTIFY, FAIL, "can't notify client of entry flush")
+    } /* if ( write_entry ) */
 
-            H5C__REMOVE_ENTRY_FROM_SLIST(cache_ptr, entry_ptr)
+    /* At this point, all pre-serialize and serialize calls have been
+     * made if it was appropriate to make them.  Similarly, the entry
+     * has been written to disk if desired.
+     *
+     * Thus it is now safe to update the cache data structures for the 
+     * flush.
+     */
 
-        }
+    /* start by updating the statistics */
+    if(clear_only) {
+        /* only log a clear if the entry was dirty */
+        if(was_dirty) {
+            H5C__UPDATE_STATS_FOR_CLEAR(cache_ptr, entry_ptr)
+        } /* end if */
+    } else if(write_entry) {
+        HDassert(was_dirty);
 
-	if ( ( ! destroy ) && ( was_dirty ) ) {
+        /* only log a flush if we actually wrote to disk */
+        H5C__UPDATE_STATS_FOR_FLUSH(cache_ptr, entry_ptr)
+    }
 
-            H5C__UPDATE_INDEX_FOR_ENTRY_CLEAN(cache_ptr, entry_ptr);
-        }
+    if(destroy) {
+        if(take_ownership)
+            HDassert(!destroy_entry);
+        else
+            HDassert(destroy_entry);
 
-        if ( ! destroy ) { /* i.e. if the entry still exists */
+        H5C__UPDATE_STATS_FOR_EVICTION(cache_ptr, entry_ptr, take_ownership)
+    }
 
-            HDassert( !(entry_ptr->is_dirty) );
-            HDassert( !(entry_ptr->flush_marker) );
-            HDassert( !(entry_ptr->in_slist) );
-            HDassert( !(entry_ptr->is_protected) );
-            HDassert( !(entry_ptr->is_read_only) );
-            HDassert( (entry_ptr->ro_ref_count) == 0 );
+    /* If the entry's type has a 'notify' callback and the entry is about
+     * to be removed from the cache, send a 'before eviction' notice while
+     * the entry is still fully integrated in the cache.
+     */
+    if(destroy)
+        if(entry_ptr->type->notify && (entry_ptr->type->notify)(H5C_NOTIFY_ACTION_BEFORE_EVICT, entry_ptr) < 0)
+            HGOTO_ERROR(H5E_CACHE, H5E_CANTNOTIFY, FAIL, "can't notify client about entry to evict")
+
+    /* Update the cache internal data structures. */
+    if(destroy) {
+        /* Update the cache internal data structures as appropriate
+         * for a destroy.  Specifically:
+         *
+         * 1) Delete it from the index
+         *
+         * 2) Delete it from the skip list if requested.
+         *
+         * 3) Update the replacement policy for eviction
+         *
+         * Finally, if the destroy_entry flag is set, discard the 
+         * entry.
+         */
 
-	    if ( (flush_flags & H5C_CALLBACK__SIZE_CHANGED_FLAG) != 0 ) {
+        H5C__DELETE_FROM_INDEX(cache_ptr, entry_ptr)
 
-		/* The entry size changed as a result of the flush.
-		 *
-		 * Most likely, the entry was compressed, and the
-		 * new version is of a different size than the old.
-		 *
-		 * In any case, we must update entry and cache size
-		 * accordingly.
-		 */
-		size_t new_size;
+        if(entry_ptr->in_slist && del_from_slist_on_destroy)
+            H5C__REMOVE_ENTRY_FROM_SLIST(cache_ptr, entry_ptr)
 
-                if ( (entry_ptr->type->size)(f, (void *)entry_ptr, &new_size)
-                     < 0 ) {
+        H5C__UPDATE_RP_FOR_EVICTION(cache_ptr, entry_ptr, FAIL)
+    }
+    else {
+        HDassert(clear_only || write_entry);
+        HDassert(entry_ptr->is_dirty);
+        HDassert(entry_ptr->in_slist);
 
-                    HGOTO_ERROR(H5E_RESOURCE, H5E_CANTGETSIZE, FAIL, \
-                                "Can't get entry size after flush")
-                }
+        /* We are either doing a flush or a clear.
+         *
+         * A clear and a flush are the same from the point of
+         * view of the replacement policy and the slist.  
+         * Hence no differentiation between them.
+         *
+         * 					JRM -- 7/7/07
+         */
 
-		if ( new_size != entry_ptr->size ) {
+        H5C__UPDATE_RP_FOR_FLUSH(cache_ptr, entry_ptr, FAIL)
 
-                    HDassert( entry_ptr->size < H5C_MAX_ENTRY_SIZE );
+        H5C__REMOVE_ENTRY_FROM_SLIST(cache_ptr, entry_ptr)
 
-                    /* update the hash table for the size change
-		     * We pass TRUE as the was_clean parameter, as we
-		     * have already updated the clean and dirty index
-		     * size fields for the fact that the entry has
-		     * been flushed. (See above call to
-		     * H5C__UPDATE_INDEX_FOR_ENTRY_CLEAN()).
-		     */
-	            H5C__UPDATE_INDEX_FOR_SIZE_CHANGE((cache_ptr), \
-				                      (entry_ptr->size), \
-                                                      (new_size), \
-						      (entry_ptr), \
-						      (TRUE))
-
-		    /* The entry can't be protected since we just flushed it.
-		     * Thus we must update the replacement policy data
-		     * structures for the size change.  The macro deals
-		     * with the pinned case.
-		     */
-		    H5C__UPDATE_RP_FOR_SIZE_CHANGE(cache_ptr, entry_ptr, \
-				                   new_size)
+        /* mark the entry as clean and update the index for 
+         * entry clean.  Also, call the clear callback 
+         * if defined.
+         */
+        entry_ptr->is_dirty = FALSE;
 
-		    /* The entry can't be in the slist, so no need to update
-		     * the slist for the size change.
-		     */
+        H5C__UPDATE_INDEX_FOR_ENTRY_CLEAN(cache_ptr, entry_ptr);
 
-		    /* update stats for the size change */
-		    H5C__UPDATE_STATS_FOR_ENTRY_SIZE_CHANGE(cache_ptr, \
-				                            entry_ptr, \
-							    new_size)
+        if(entry_ptr->type->clear && (entry_ptr->type->clear)(f, (void *)entry_ptr, FALSE) < 0)
+            HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "unable to clear entry")
+    }
 
-		    /* finally, update the entry size proper */
-		    entry_ptr->size = new_size;
-		}
-	    }
+    /* reset the flush_in progress flag */
+    entry_ptr->flush_in_progress = FALSE;
 
-	    if ( (flush_flags & H5C_CALLBACK__MOVED_FLAG) != 0 ) {
-
-		/* The entry was moved as the result of the flush.
-		 *
-		 * Most likely, the entry was compressed, and the
-		 * new version is larger than the old and thus had
-		 * to be relocated.
-		 *
-		 * At preset, all processing for this case is
-		 * handled elsewhere.  But lets keep the if statement
-		 * around just in case.
-		 */
+    /* Internal cache data structures should now be up to date, and 
+     * consistant with the status of the entry.  
+     *
+     * Now discard the entry if appropriate.
+     */
+    if(destroy) {
+        /* start by freeing the buffer for the on disk image */
+        if(entry_ptr->image_ptr != NULL)
+            entry_ptr->image_ptr = H5MM_xfree(entry_ptr->image_ptr);
 
-	    }
+        /* Check whether we should free the space in the file that 
+         * the entry occupies 
+         */
+        if(free_file_space) {
+            size_t fsf_size;
 
-        /* reset the flush_in progress flag */
-	    entry_ptr->flush_in_progress = FALSE;
-        }
+            /* Sanity checks */
+            HDassert(H5F_addr_defined(entry_ptr->addr));
+            HDassert(!H5F_IS_TMP_ADDR(f, entry_ptr->addr));
+#ifndef NDEBUG
+{
+            hbool_t curr_compressed = FALSE;
+            size_t curr_len;
+            size_t curr_compressed_len = 0;
+
+            /* Get the actual image size for the thing again */
+            entry_ptr->type->image_len((void *)entry_ptr, &curr_len, &curr_compressed, &curr_compressed_len);
+            HDassert(curr_len == entry_ptr->size);
+            HDassert(curr_compressed == entry_ptr->compressed);
+            HDassert(curr_compressed_len == entry_ptr->compressed_size);
+}
+#endif /* NDEBUG */
+
+            /* if the file space free size callback is defined, use
+             * it to get the size of the block of file space to free.
+             * Otherwise use entry_ptr->compressed_size if 
+             * entry_ptr->compressed == TRUE, and entry_ptr->size
+             * if entry_ptr->compressed == FALSE.
+             */
+            if(entry_ptr->type->fsf_size) {
+                if((entry_ptr->type->fsf_size)((void *)entry_ptr, &fsf_size) < 0)
+                    HGOTO_ERROR(H5E_CACHE, H5E_CANTFREE, FAIL, "unable to get file space free size")
+            } /* end if */
+            else if(entry_ptr->compressed) /* use compressed size */
+                fsf_size = entry_ptr->compressed_size;
+            else    /* no file space free size callback -- use entry size */
+                fsf_size = entry_ptr->size;
+
+            /* Release the space on disk */
+            if(H5MF_xfree(f, entry_ptr->type->mem_type, dxpl_id, entry_ptr->addr, (hsize_t)fsf_size) < 0)
+                HGOTO_ERROR(H5E_CACHE, H5E_CANTFREE, FAIL, "unable to free file space for cache entry")
+        } /* end if ( free_file_space ) */
+
+        /* Reset the pointer to the cache the entry is within. -QAK */
+        entry_ptr->cache_ptr = NULL;
+
+        /* increment entries_removed_counter and set 
+         * last_entry_removed_ptr.  As we are likely abuut to 
+         * free the entry, recall that last_entry_removed_ptr 
+         * must NEVER be dereferenced.
+         *
+         * Recall that these fields are maintained to allow functions
+         * that perform scans of lists of entries to detect the 
+         * unexpected removal of entries (via expunge, eviction, 
+         * or take ownership at present), so that they can re-start
+         * their scans if necessary.
+         */
+        cache_ptr->last_entry_removed_ptr++;
+        cache_ptr->last_entry_removed_ptr = entry_ptr;
+
+        /* Check for actually destroying the entry in memory */
+        /* (As opposed to taking ownership of it) */
+        if(destroy_entry) {
+            /* if the entry is dirty and it has a clear callback,
+             * call this callback now.  Since this callback exists,
+             * it follows tht the client maintains its own dirty bits, 
+             * which must be cleared before the entry is freed to avoid 
+             * sanity check failures.  Also clear the dirty flag for 
+             * the same reason.
+             */
+            if(entry_ptr->is_dirty) {
+                entry_ptr->is_dirty = FALSE;
 
-        if ( cache_ptr->log_flush ) {
+                if(entry_ptr->type->clear && (entry_ptr->type->clear)(f, (void *)entry_ptr, TRUE) < 0)
+                    HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "unable to clear entry")
+            }
 
-            status = (cache_ptr->log_flush)(cache_ptr, addr, was_dirty, flags);
+            /* we are about to discard the in core representation --
+             * set the magic field to bad magic so we can detect a
+             * freed entry if we see one.
+             */
+            entry_ptr->magic = H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC;
 
-            if ( status < 0 ) {
+            /* verify that the image has been freed */
+            HDassert(entry_ptr->image_ptr == NULL);
 
-                HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, \
-                            "log_flush callback failed.")
-            }
+            if(entry_ptr->type->free_icr((void *)entry_ptr) < 0)
+                HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "free_icr callback failed.")
+        } 
+        else {
+            HDassert(take_ownership);
+
+            /* client is taking ownership of the entry.
+             * set bad magic here too so the cache will choke 
+             * unless the entry is re-inserted properly
+             */
+            entry_ptr->magic = H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC;
         }
-    }
+    } /* if (destroy) */
+
+    if(cache_ptr->log_flush)
+        if((cache_ptr->log_flush)(cache_ptr, entry_ptr->addr, was_dirty, flags) < 0)
+            HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "log_flush callback failed.")
 
 done:
-    HDassert( ( destroy ) || 
-              ( ( entry_ptr ) && ( ! entry_ptr->flush_in_progress ) ) );
+    HDassert( ( ret_value != SUCCEED ) || ( destroy_entry ) || 
+              ( ! entry_ptr->flush_in_progress ) );
+
+    HDassert( ( ret_value != SUCCEED ) || ( destroy_entry ) || 
+              ( take_ownership ) || ( ! entry_ptr->is_dirty ) );
+
     FUNC_LEAVE_NOAPI(ret_value)
-} /* H5C_flush_single_entry() */
+} /* H5C__flush_single_entry() */
 
 
 /*-------------------------------------------------------------------------
@@ -8637,8 +8183,19 @@ H5C_load_entry(H5F_t *             f,
                haddr_t             addr,
                void *              udata)
 {
+    hbool_t		dirty = FALSE;  /* Flag indicating whether thing was dirtied during deserialize */
+    hbool_t		compressed = FALSE; /* flag indicating whether thing */
+ 					/* will be run through filters on    */
+                                        /* on read and write.  Usually FALSE */
+					/* set to true if appropriate.       */
+    size_t		compressed_size = 0; /* entry compressed size if     */
+                                        /* known -- otherwise uncompressed.  */
+				        /* Zero indicates compression not    */
+                                        /* enabled.                          */
+    void *		image = NULL;   /* Buffer for disk image */
     void *		thing = NULL;   /* Pointer to thing loaded */
     H5C_cache_entry_t *	entry;          /* Alias for thing loaded, as cache entry */
+    size_t              len;            /* Size of image in file */
     unsigned            u;              /* Local index variable */
     void *		ret_value;      /* Return value */
 
@@ -8648,14 +8205,310 @@ H5C_load_entry(H5F_t *             f,
     HDassert(f->shared);
     HDassert(f->shared->cache);
     HDassert(type);
-    HDassert(type->load);
-    HDassert(type->size);
+
+    /* verify absence of prohibited or unsupported type flag combinations */
+    HDassert(!(type->flags & H5C__CLASS_NO_IO_FLAG));
+ 
+    /* for now, we do not combine the speculative load and compressed flags */
+    HDassert(!((type->flags & H5C__CLASS_SPECULATIVE_LOAD_FLAG) &&
+               (type->flags & H5C__CLASS_COMPRESSED_FLAG)));
+
+    /* Can't see how skip reads could be usefully combined with 
+     * either the speculative read or compressed flags.  Hence disallow.
+     */
+    HDassert(!((type->flags & H5C__CLASS_SKIP_READS) &&
+               (type->flags & H5C__CLASS_SPECULATIVE_LOAD_FLAG)));
+    HDassert(!((type->flags & H5C__CLASS_SKIP_READS) &&
+               (type->flags & H5C__CLASS_COMPRESSED_FLAG)));
+
     HDassert(H5F_addr_defined(addr));
+    HDassert(type->get_load_size);
+    HDassert(type->deserialize);
+
+    /* Call the get_load_size callback, to retrieve the initial 
+     * size of image 
+     */
+    if(type->get_load_size(udata, &len) < 0)
+        HGOTO_ERROR(H5E_CACHE, H5E_CANTGET, NULL, "can't retrieve image size")
+
+    HDassert(len > 0);
+
+    /* Check for possible speculative read off the end of the file */
+    if(type->flags & H5C__CLASS_SPECULATIVE_LOAD_FLAG) {
+
+/* Quincey has added patches for eoa calculations -- leave the original
+ * code around until we see the effect of these patches.
+ *                                         JRM -- 1/1/15
+ */
+#if 0 /* original code */ /* JRM */
+	/* the original version of this code has several problems:
+         *
+         * First, the sblock is not available until the sblock 
+         * has been read in, which causes a seg fault.  This is 
+         * dealt with easily enough by testing to see if 
+         * f->shared->sblock is NULL, and calling H5FD_get_base_addr()
+         * to obtain the base addr when it is.
+         *
+         * The second issue is more subtle.  H5F_get_eoa() calls 
+         * H5FD_get_eoa().  However, this function returns the EOA as 
+         * a relative address -- i.e. relative to the base address.
+         * This means that the base addr + addr < eoa sanity check will
+         * fail whenever the super block is not at address 0 when 
+         * reading in the first chunk of the super block.
+         * 
+         * To address these issues, I have rewritten the code to 
+         * simply verify that the address plus length is less than 
+         * the eoa.  I think this is sufficient, but further testing
+         * should tell me if it isn't.
+         *                                      JRM -- 8/29/14
+         */
+        haddr_t eoa;                /* End-of-allocation in the file */
+        haddr_t base_addr;          /* Base address of file data */
+
+        /* Get the file's end-of-allocation value */
+        eoa = H5F_get_eoa(f, type->mem_type);
+        HDassert(H5F_addr_defined(eoa));
+
+        /* Get the file's base address */
+	if ( f->shared->sblock ) 
+
+            base_addr = H5F_BASE_ADDR(f);
+
+	else { /* sblock not loaded yet -- use file driver info */
+
+	    HDassert(f->shared->lf);
+	    base_addr = H5FD_get_base_addr(f->shared->lf);
+
+	}
+        HDassert(H5F_addr_defined(base_addr));
+
+        /* Check for bad address in general */
+        if((addr + base_addr) > eoa)
+            HGOTO_ERROR(H5E_CACHE, H5E_BADVALUE, NULL, \
+	                "address of object past end of allocation")
+
+        /* Check if the amount of data to read will be past the eoa */
+        if((addr + base_addr + len) > eoa)
+            /* Trim down the length of the metadata */
+            len = (size_t)(eoa - (addr + base_addr));
+
+#else /* modified code */ /* JRM */
+
+        haddr_t eoa;                /* End-of-allocation in the file */
+        H5FD_mem_t  cooked_type;
+
+	/* if type == H5FD_MEM_GHEAP, H5F_block_read() forces 
+         * type to H5FD_MEM_DRAW via its call to H5F__accum_read().
+         * Thus we do the same for purposes of computing the eoa
+         * for sanity checks.
+         */
+        cooked_type = 
+           (type->mem_type == H5FD_MEM_GHEAP) ? H5FD_MEM_DRAW : type->mem_type;
+
+        /* Get the file's end-of-allocation value */
+        eoa = H5F_get_eoa(f, cooked_type);
+
+        HDassert(H5F_addr_defined(eoa));
+
+        /* Check for bad address in general */
+        if ( H5F_addr_gt(addr, eoa) )
+
+            HGOTO_ERROR(H5E_CACHE, H5E_BADVALUE, NULL, \
+	                "address of object past end of allocation")
+
+        /* Check if the amount of data to read will be past the eoa */
+        if( H5F_addr_gt((addr + len), eoa) ) {
+
+            /* Trim down the length of the metadata */
+
+            /* Note that for some cache clients, this will cause an 
+             * assertion failure.		JRM -- 8/29/14
+             */
+            len = (size_t)(eoa - addr);
+        }
+
+        if ( len <= 0 )
+            HGOTO_ERROR(H5E_CACHE, H5E_BADVALUE, NULL, \
+	                "len not positive after adjustment for EOA.")
+
+#endif /* modified code */ /* JRM */
+    }
+    /* Allocate the buffer for reading the on-disk entry image */
+    if(NULL == (image = H5MM_malloc(len + H5C_IMAGE_EXTRA_SPACE)))
+
+        HGOTO_ERROR(H5E_CACHE, H5E_CANTALLOC, NULL, \
+                    "memory allocation failed for on disk image buffer.")
+
+#if H5C_DO_MEMORY_SANITY_CHECKS
+    HDmemcpy(((uint8_t *)image) + len, H5C_IMAGE_SANITY_VALUE, H5C_IMAGE_EXTRA_SPACE);
+#endif /* H5C_DO_MEMORY_SANITY_CHECKS */
+
+    /* Get the on-disk entry image */
+    if ( 0 == (type->flags & H5C__CLASS_SKIP_READS) )
+        if(H5F_block_read(f, type->mem_type, addr, len, dxpl_id, image) < 0)
+            HGOTO_ERROR(H5E_CACHE, H5E_READERROR, NULL, "Can't read image*")
+
+    /* Deserialize the on-disk image into the native memory form */
+    if(NULL == (thing = type->deserialize(image, len, udata, &dirty)))
+        HGOTO_ERROR(H5E_CACHE, H5E_CANTLOAD, NULL, "Can't deserialize image")
+
+    /* If the client's cache has an image_len callback, check it */
+    if(type->image_len) {
+        size_t	new_len;        /* New size of on-disk image */
+
+	/* set magic and type field in *entry_ptr.  While the image_len 
+         * callback shouldn't touch the cache specific fields, it may check 
+         * these fields to ensure that it it has received the expected 
+         * value.
+         *
+         * Note that this initialization is repeated below on the off 
+         * chance that we had to re-try the deserialization.
+         */
+        entry = (H5C_cache_entry_t *)thing;
+        entry->magic = H5C__H5C_CACHE_ENTRY_T_MAGIC;
+        entry->type  = type;
+
+	/* verify that compressed and compressed_len are initialized */
+        HDassert(compressed == FALSE);
+        HDassert(compressed_size == 0);
+
+        /* Get the actual image size for the thing */
+        if(type->image_len(thing, &new_len, &compressed, &compressed_size) < 0)
+
+	    HGOTO_ERROR(H5E_CACHE, H5E_CANTGET, NULL, \
+                        "can't retrieve image length")
+
+	if(new_len == 0)
+
+	    HGOTO_ERROR(H5E_CACHE, H5E_BADVALUE, NULL, "image length is 0")
+
+        HDassert(((type->flags & H5C__CLASS_COMPRESSED_FLAG) != 0) ||
+                 ((compressed == FALSE) && (compressed_size == 0)));
+        HDassert((compressed == TRUE) || (compressed_size == 0));
+
+	if(new_len != len) {
+
+            if(type->flags & H5C__CLASS_COMPRESSED_FLAG) {
+
+                /* if new_len != len, then compression must be 
+                 * enabled on the entry.  In this case, the image_len
+                 * callback should have set compressed to TRUE, set 
+                 * new_len equal to the uncompressed size of the 
+                 * entry, and compressed_len equal to the compressed
+                 * size -- which must equal len.
+                 *
+                 * We can't verify the uncompressed size, but we can 
+		 * verify the rest with the following assertions.
+                 */
+		HDassert(compressed);
+                HDassert(compressed_size == len);
+
+		/* new_len should contain the uncompressed size.  Set len
+                 * equal to new_len, so that the cache will use the 
+                 * uncompressed size for purposes of space allocation, etc.
+                 */
+                len = new_len;
+
+            } else if (type->flags & H5C__CLASS_SPECULATIVE_LOAD_FLAG) {
+
+                void *new_image;       /* Buffer for disk image */
+
+		/* compressed must be FALSE, and compressed_size 
+                 * must be zero.
+                 */
+		HDassert(!compressed);
+		HDassert(compressed_size == 0);
+
+                /* Adjust the size of the image to match new_len */
+                if(NULL == (new_image = H5MM_realloc(image, 
+                                            new_len + H5C_IMAGE_EXTRA_SPACE)))
+
+                    HGOTO_ERROR(H5E_CACHE, H5E_CANTALLOC, NULL, \
+                               "image null after H5MM_realloc()")
+
+                image = new_image;
+
+#if H5C_DO_MEMORY_SANITY_CHECKS
+
+                HDmemcpy(((uint8_t *)image) + new_len, 
+                         H5C_IMAGE_SANITY_VALUE, H5C_IMAGE_EXTRA_SPACE);
+
+#endif /* H5C_DO_MEMORY_SANITY_CHECKS */
+
+                /* If the thing's image needs to be bigger for a speculatively
+                 *      loaded thing, free the thing and retry with new length
+                 */
+                if (new_len > len) {
+
+                    /* Release previous (possibly partially initialized) 
+                     * thing.  Note that we must set entry->magic to 
+                     * H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC and set one or 
+                     * two other fields before the call to free_icr
+                     * so as to avoid sanity check failures.
+                     */
+                    entry->magic = H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC;
+
+                    entry->addr  = addr;
+
+                    if ( type->free_icr(thing) < 0 )
 
-    if(NULL == (thing = (type->load)(f, dxpl_id, addr, udata)))
+                        HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, NULL, \
+                                    "free_icr callback failed")
 
-        HGOTO_ERROR(H5E_CACHE, H5E_CANTLOAD, NULL, "unable to load entry")
+                    /* Go get the on-disk image again */
+                    if(H5F_block_read(f, type->mem_type, addr, 
+                                      new_len, dxpl_id, image) < 0)
 
+                        HGOTO_ERROR(H5E_CACHE, H5E_CANTLOAD, NULL, \
+                                    "Can't read image")
+
+                    /* Deserialize on-disk image into native memory 
+                     * form again 
+                     */
+                    if(NULL == (thing = type->deserialize(image, new_len, 
+                                                          udata, &dirty)))
+
+                        HGOTO_ERROR(H5E_CACHE, H5E_CANTLOAD, NULL, \
+                                    "Can't deserialize image")
+
+#ifndef NDEBUG
+    		    {
+			/* new_compressed and new_compressed_size must be 
+                         * initialize to FALSE / 0 respectively, as clients
+                         * that don't use compression may ignore these two 
+                         * parameters.
+                         */
+                        hbool_t new_compressed = FALSE;
+                        size_t new_compressed_size = 0;
+                        size_t new_new_len;
+
+                        /* Get the actual image size for the thing again.  Note
+                         * that since this is a new thing, we have to set 
+                         * the magic and type fields again so as to avoid
+                         * failing sanity checks.
+                         */
+                        entry = (H5C_cache_entry_t *)thing;
+                        entry->magic = H5C__H5C_CACHE_ENTRY_T_MAGIC;
+                        entry->type  = type;
+
+                        type->image_len(thing, &new_new_len, &new_compressed, &new_compressed_size);
+                        HDassert(new_new_len == new_len);
+                        HDassert(!new_compressed);
+                        HDassert(new_compressed_size == 0);
+    		    }
+#endif /* NDEBUG */
+                } /* end if (new_len > len) */
+
+                /* Retain adjusted size */
+                len = new_len;
+
+            } else { /* throw an error */
+
+                HGOTO_ERROR(H5E_CACHE, H5E_UNSUPPORTED, NULL, \
+                     "size of non-speculative, non-compressed object changed")
+            }
+	} /* end if (new_len != len) */
+    } /* end if */
 
     entry = (H5C_cache_entry_t *)thing;
 
@@ -8663,35 +8516,39 @@ H5C_load_entry(H5F_t *             f,
      *
      * However, when this code is used in the metadata cache, it is
      * possible that object headers will be dirty at this point, as
-     * the load function will alter object headers if necessary to
+     * the deserialize function will alter object headers if necessary to
      * fix an old bug.
      *
-     * To support this bug fix, I have replace the old assert:
-     *
-     * 	HDassert( entry->is_dirty == FALSE );
+     * In the following assert:
      *
-     * with:
+     * 	HDassert( ( dirty == FALSE ) || ( type->id == 5 || type->id == 6 ) );
      *
-     * 	HDassert( ( entry->is_dirty == FALSE ) || ( type->id == 5 ) );
-     *
-     * Note that type id 5 is associated with object headers in the metadata
-     * cache.
+     * note that type ids 5 & 6 are associated with object headers in the 
+     * metadata cache.
      *
      * When we get to using H5C for other purposes, we may wish to
      * tighten up the assert so that the loophole only applies to the
      * metadata cache.
      */
 
-    HDassert( ( entry->is_dirty == FALSE ) || ( type->id == 5 ) );
-#ifndef NDEBUG
+    HDassert( ( dirty == FALSE ) || ( type->id == 5 || type->id == 6) );
+
     entry->magic                = H5C__H5C_CACHE_ENTRY_T_MAGIC;
-#endif /* NDEBUG */
     entry->cache_ptr            = f->shared->cache;
     entry->addr                 = addr;
+    entry->size                 = len;
+    HDassert(entry->size < H5C_MAX_ENTRY_SIZE);
+    entry->compressed		= compressed;
+    entry->compressed_size	= compressed_size;
+    entry->image_ptr            = image;
+    entry->image_up_to_date     = TRUE;
     entry->type                 = type;
+    entry->is_dirty	        = dirty;
+    entry->dirtied              = FALSE;
     entry->is_protected         = FALSE;
     entry->is_read_only         = FALSE;
     entry->ro_ref_count         = 0;
+    entry->is_pinned            = FALSE;
     entry->in_slist             = FALSE;
     entry->flush_marker         = FALSE;
 #ifdef H5_HAVE_PARALLEL
@@ -8700,13 +8557,6 @@ H5C_load_entry(H5F_t *             f,
 #endif /* H5_HAVE_PARALLEL */
     entry->flush_in_progress    = FALSE;
     entry->destroy_in_progress  = FALSE;
-    entry->free_file_space_on_destroy = FALSE;
-
-    if((type->size)(f, thing, &(entry->size)) < 0)
-
-        HGOTO_ERROR(H5E_RESOURCE, H5E_CANTGETSIZE, NULL, "Can't get size of thing")
-
-    HDassert( entry->size < H5C_MAX_ENTRY_SIZE );
 
     /* Initialize flush dependency height fields */
     entry->flush_dep_parent = NULL;
@@ -8727,6 +8577,18 @@ H5C_load_entry(H5F_t *             f,
     ret_value = thing;
 
 done:
+    /* Cleanup on error */
+    if(NULL == ret_value) {
+
+        /* Release resources */
+        if ( thing && type->free_icr(thing) < 0 )
+
+            HDONE_ERROR(H5E_CACHE, H5E_CANTFLUSH, NULL, \
+                        "free_icr callback failed")
+
+        if(image)
+            image = H5MM_xfree(image);
+    } /* end if */
 
     FUNC_LEAVE_NOAPI(ret_value)
 } /* H5C_load_entry() */
@@ -8765,39 +8627,47 @@ done:
  *
  * Programmer:  John Mainzer, 5/14/04
  *
- *              JRM -- 11/13/08
- *              Modified function to always observe the min_clean_size
- *              whether we are maintaining the clean and dirt LRU lists
- *              or not.  To do this, we had to add the new clean_index_size
- *              and dirty_index_size fields to H5C_t, and supporting code
- *              as needed throughout the cache.
+ * Changes:     Modified function to skip over entries with the 
+ *		flush_in_progress flag set.  If this is not done,
+ *		an infinite recursion is possible if the cache is 
+ *		full, and the pre-serialize or serialize routine 
+ *		attempts to load another entry.
  *
- *              The purpose of this modification is to avoid "metadata
- *              blizzards" in the write only case.  In such instances,
- *              the cache was allowed to fill with dirty metadata.  When
- *              we finally needed to evict an entry to make space, we had
- *              to flush out a whole cache full of metadata -- which has
- *              interesting performance effects.  We hope to avoid (or
- *              perhaps more accurately hide) this effect by maintaining
- *              the min_clean_size, which should force us to start flushing
- *              entries long before we actually have to evict something
- *              to make space.
+ *		This error was exposed by a re-factor of the 
+ *		H5C__flush_single_entry() routine.  However, it was 
+ *		a potential bug from the moment that entries were 
+ *		allowed to load other entries on flush.
+ *
+ *		In passing, note that the primary and secondary dxpls 
+ *		mentioned in the comment above have been replaced by 
+ *		a single dxpl at some point, and thus the discussion 
+ *		above is somewhat obsolete.  Date of this change is 
+ *		unkown.
+ *
+ *						JRM -- 12/26/14
+ *
+ *		Modified function to detect deletions of entries 
+ *		during a scan of the LRU, and where appropriate, 
+ *		restart the scan to avoid proceeding with a next 
+ *		entry that is no longer in the cache.
+ *
+ *		Note the absence of checks after flushes of clean 
+ *		entries.  As a second entry can only be removed by 
+ *		by a call to the pre_serialize or serialize callback
+ *		of the first, and as these callbacks will not be called
+ *		on clean entries, no checks are needed.
+ *
+ *						JRM -- 4/6/15
  *
- *              MAM -- 01/06/09
- *              Added code to maintain clean_entries_skipped and total_entries
- *              scanned statistics.
  *-------------------------------------------------------------------------
  */
 static herr_t
 H5C_make_space_in_cache(H5F_t *	f,
-                        hid_t	primary_dxpl_id,
-                        hid_t	secondary_dxpl_id,
+                        hid_t	dxpl_id,
 		        size_t	space_needed,
-                        hbool_t	write_permitted,
-                        hbool_t * first_flush_ptr)
+                        hbool_t	write_permitted)
 {
     H5C_t *		cache_ptr = f->shared->cache;
-    herr_t		result;
 #if H5C_COLLECT_CACHE_STATS
     int32_t             clean_entries_skipped = 0;
     int32_t             total_entries_scanned = 0;
@@ -8807,6 +8677,7 @@ H5C_make_space_in_cache(H5F_t *	f,
     size_t		empty_space;
     hbool_t		prev_is_dirty = FALSE;
     hbool_t             didnt_flush_entry = FALSE;
+    hbool_t		restart_scan;
     H5C_cache_entry_t *	entry_ptr;
     H5C_cache_entry_t *	prev_ptr;
     H5C_cache_entry_t *	next_ptr;
@@ -8817,13 +8688,12 @@ H5C_make_space_in_cache(H5F_t *	f,
     HDassert( f );
     HDassert( cache_ptr );
     HDassert( cache_ptr->magic == H5C__H5C_T_MAGIC );
-    HDassert( first_flush_ptr != NULL );
-    HDassert( ( *first_flush_ptr == TRUE ) || ( *first_flush_ptr == FALSE ) );
     HDassert( cache_ptr->index_size ==
 	      (cache_ptr->clean_index_size + cache_ptr->dirty_index_size) );
 
     if ( write_permitted ) {
 
+        restart_scan = FALSE;
         initial_list_len = cache_ptr->LRU_list_len;
         entry_ptr = cache_ptr->LRU_tail_ptr;
 
@@ -8854,6 +8724,7 @@ H5C_make_space_in_cache(H5F_t *	f,
                 ( entry_ptr != NULL )
               )
         {
+            HDassert(entry_ptr->magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
             HDassert( ! (entry_ptr->is_protected) );
             HDassert( ! (entry_ptr->is_read_only) );
             HDassert( (entry_ptr->ro_ref_count) == 0 );
@@ -8866,7 +8737,8 @@ H5C_make_space_in_cache(H5F_t *	f,
 		prev_is_dirty = prev_ptr->is_dirty;
 	    }
 
-            if ( (entry_ptr->type)->id != H5C__EPOCH_MARKER_TYPE ) {
+            if ( ( (entry_ptr->type)->id != H5C__EPOCH_MARKER_TYPE ) &&
+                 ( ! entry_ptr->flush_in_progress ) ) {
 
                 didnt_flush_entry = FALSE;
 
@@ -8881,14 +8753,25 @@ H5C_make_space_in_cache(H5F_t *	f,
                     }
 #endif /* H5C_COLLECT_CACHE_STATS */
 
-                    result = H5C_flush_single_entry(f,
-                                                    primary_dxpl_id,
-                                                    secondary_dxpl_id,
-                                                    entry_ptr->type,
-                                                    entry_ptr->addr,
-                                                    H5C__NO_FLAGS_SET,
-                                                    first_flush_ptr,
-                                                    FALSE);
+		    /* reset entries_removed_counter and 
+                     * last_entry_removed_ptr prior to the call to 
+                     * H5C__flush_single_entry() so that we can spot 
+                     * unexpected removals of entries from the cache,
+                     * and set the restart_scan flag if proceeding 
+                     * would be likely to cause us to scan an entry 
+                     * that is no longer in the cache.
+                     */
+                    cache_ptr->entries_removed_counter = 0;
+                    cache_ptr->last_entry_removed_ptr  = NULL;
+
+                    if(H5C__flush_single_entry(f, dxpl_id, entry_ptr, H5C__NO_FLAGS_SET, NULL) < 0)
+                        HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "unable to flush entry")
+
+		    if ( ( cache_ptr->entries_removed_counter > 1 ) ||
+                         ( cache_ptr->last_entry_removed_ptr == prev_ptr ) )
+
+                        restart_scan = TRUE;
+
                 } else if ( (cache_ptr->index_size + space_needed)
                               >
                              cache_ptr->max_cache_size ) {
@@ -8896,26 +8779,15 @@ H5C_make_space_in_cache(H5F_t *	f,
                     cache_ptr->entries_scanned_to_make_space++;
 #endif /* H5C_COLLECT_CACHE_STATS */
 
-                    result = H5C_flush_single_entry(f,
-                                                    primary_dxpl_id,
-                                                    secondary_dxpl_id,
-                                                    entry_ptr->type,
-                                                    entry_ptr->addr,
-                                                    H5C__FLUSH_INVALIDATE_FLAG,
-                                                    first_flush_ptr,
-                                                    TRUE);
-                } else {
+                    if(H5C__flush_single_entry(f, dxpl_id, entry_ptr, H5C__FLUSH_INVALIDATE_FLAG | H5C__DEL_FROM_SLIST_ON_DESTROY_FLAG, NULL) < 0)
+                        HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "unable to flush entry")
 
-                    /* We have enough space so don't flush clean entry.
-                     * Set result to SUCCEED to avoid triggering the error
-                     * code below.
-                     */
+                } else {
+                    /* We have enough space so don't flush clean entry. */
 #if H5C_COLLECT_CACHE_STATS
                     clean_entries_skipped++;
 #endif /* H5C_COLLECT_CACHE_STATS */
                     didnt_flush_entry = TRUE;
-                    result = SUCCEED;
-
                 }
 
 #if H5C_COLLECT_CACHE_STATS
@@ -8924,40 +8796,27 @@ H5C_make_space_in_cache(H5F_t *	f,
 
             } else {
 
-                /* Skip epoch markers.  Set result to SUCCEED to avoid
-                 * triggering the error code below.
+                /* Skip epoch markers and entries that are in the process
+                 * of being flushed.
                  */
                 didnt_flush_entry = TRUE;
-                result = SUCCEED;
-            }
-
-            if ( result < 0 ) {
-
-                HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, \
-                            "unable to flush entry")
             }
 
 	    if ( prev_ptr != NULL ) {
-#ifndef NDEBUG
-		if ( prev_ptr->magic != H5C__H5C_CACHE_ENTRY_T_MAGIC ) {
-
-		    /* something horrible has happened to *prev_ptr --
-		     * scream and die.
-		     */
-                    HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, \
-				"*prev_ptr corrupt 1")
 
-                }
-#endif /* NDEBUG */
 		if ( didnt_flush_entry ) {
 
-		    /* epoch markers don't get flushed, so the sanity checks
-		     * on normal entries will fail -- thus just set entry_ptr
-		     * to prev_ptr and go on.
+		    /* epoch markers don't get flushed, and we don't touch 
+                     * entries that are in the process of being flushed.
+                     * Hence no need for sanity checks, as we haven't 
+                     * flushed anything.  Thus just set entry_ptr to prev_ptr 
+                     * and go on.
 		     */
                     entry_ptr = prev_ptr;
 
-		} else if ( ( prev_ptr->is_dirty != prev_is_dirty )
+		} else if ( ( restart_scan ) 
+                            ||
+                            ( prev_ptr->is_dirty != prev_is_dirty )
 		            ||
 		            ( prev_ptr->next != next_ptr )
 		            ||
@@ -8968,7 +8827,9 @@ H5C_make_space_in_cache(H5F_t *	f,
 		    /* something has happened to the LRU -- start over
 		     * from the tail.
 		     */
+                    restart_scan = FALSE;
 	            entry_ptr = cache_ptr->LRU_tail_ptr;
+		    H5C__UPDATE_STATS_FOR_LRU_SCAN_RESTART(cache_ptr)
 
 		} else {
 
@@ -9055,20 +8916,14 @@ H5C_make_space_in_cache(H5F_t *	f,
 
             prev_ptr = entry_ptr->aux_prev;
 
-            result = H5C_flush_single_entry(f,
-                                            primary_dxpl_id,
-                                            secondary_dxpl_id,
-                                            entry_ptr->type,
-                                            entry_ptr->addr,
-                                            H5C__FLUSH_INVALIDATE_FLAG,
-                                            first_flush_ptr,
-                                            TRUE);
+            if(H5C__flush_single_entry(f, dxpl_id, entry_ptr, H5C__FLUSH_INVALIDATE_FLAG | H5C__DEL_FROM_SLIST_ON_DESTROY_FLAG, NULL) < 0)
+                HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "unable to flush entry")
 
-            if ( result < 0 ) {
-
-                HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, \
-                            "unable to flush entry")
-            }
+	    /* we are scanning the clean LRU, so the serialize function
+	     * will not be called on any entry -- thus there is no
+	     * concern about the list being modified out from under
+	     * this function.
+	     */
 
             entry_ptr = prev_ptr;
 	    entries_examined++;
@@ -9482,6 +9337,66 @@ done:
 
 /*-------------------------------------------------------------------------
  *
+ * Function:    H5C_entry_in_skip_list
+ *
+ * Purpose:     Debugging function that scans skip list to see if it 
+ *		is in present.  We need this, as it is possible for 
+ *		an entry to be in the skip list twice.
+ *
+ * Return:      FALSE if the entry is not in the skip list, and TRUE 
+ *		if it is.
+ *
+ * Programmer:  John Mainzer, 11/1/14
+ *
+ * Changes:
+ *
+ *		None.
+ *
+ *-------------------------------------------------------------------------
+ */
+#if H5C_DO_SLIST_SANITY_CHECKS
+
+static hbool_t
+H5C_entry_in_skip_list(H5C_t * cache_ptr, H5C_cache_entry_t *target_ptr)
+{
+    hbool_t in_slist              = FALSE;
+    H5SL_node_t *       node_ptr  = NULL;
+    H5C_cache_entry_t *	entry_ptr = NULL;
+
+    HDassert( cache_ptr );
+    HDassert( cache_ptr->magic == H5C__H5C_T_MAGIC );
+    HDassert( cache_ptr->slist_ptr );
+
+    node_ptr = H5SL_first(cache_ptr->slist_ptr);
+
+    while ( ( node_ptr != NULL ) && ( ! in_slist ) )
+    {
+        entry_ptr = (H5C_cache_entry_t *)H5SL_item(node_ptr);
+
+	HDassert( entry_ptr );
+	HDassert( entry_ptr->magic == H5C__H5C_CACHE_ENTRY_T_MAGIC );
+        HDassert( entry_ptr->is_dirty );
+        HDassert( entry_ptr->in_slist );
+
+        if ( entry_ptr == target_ptr ) {
+
+	    in_slist = TRUE;
+
+	} else {
+
+	    node_ptr = H5SL_next(node_ptr);
+	}
+    }
+
+    return(in_slist);
+
+} /* H5C_entry_in_skip_list() */
+
+#endif /* H5C_DO_SLIST_SANITY_CHECKS */
+
+
+/*-------------------------------------------------------------------------
+ *
  * Function:    H5C_get_entry_ptr_from_addr()
  *
  * Purpose:     Debugging function that attempts to look up an entry in the 
@@ -9784,7 +9699,7 @@ done:
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5C_flush_tagged_entries(H5F_t * f, hid_t primary_dxpl_id, hid_t secondary_dxpl_id, H5C_t * cache_ptr, haddr_t tag)
+H5C_flush_tagged_entries(H5F_t * f, hid_t dxpl_id, H5C_t * cache_ptr, haddr_t tag)
 {
     herr_t      ret_value = SUCCEED;
 
@@ -9800,7 +9715,7 @@ H5C_flush_tagged_entries(H5F_t * f, hid_t primary_dxpl_id, hid_t secondary_dxpl_
         HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "Can't mark tagged entries")
 
     /* Flush all marked entries */
-    if(H5C_flush_marked_entries(f, primary_dxpl_id, secondary_dxpl_id, cache_ptr) < 0)
+    if(H5C_flush_marked_entries(f, dxpl_id) < 0)
         HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "Can't flush marked entries")
 
 done:
@@ -9873,7 +9788,7 @@ H5C_mark_tagged_entries(H5C_t * cache_ptr, haddr_t tag)
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5C_flush_marked_entries(H5F_t * f, hid_t primary_dxpl_id, hid_t secondary_dxpl_id, H5C_t * cache_ptr)
+H5C_flush_marked_entries(H5F_t * f, hid_t dxpl_id)
 { 
     herr_t ret_value = SUCCEED;
 
@@ -9881,12 +9796,10 @@ H5C_flush_marked_entries(H5F_t * f, hid_t primary_dxpl_id, hid_t secondary_dxpl_
 
     /* Assertions */
     HDassert(0); /* This function is not yet used. We shouldn't be in here yet. */
-    HDassert(cache_ptr != NULL);
-    HDassert(cache_ptr->magic == H5C__H5C_T_MAGIC);
+    HDassert(f != NULL);
 
     /* Flush all marked entries */
-    if(H5C_flush_cache(f, primary_dxpl_id, secondary_dxpl_id,
-            H5C__FLUSH_MARKED_ENTRIES_FLAG | H5C__FLUSH_IGNORE_PROTECTED_FLAG) < 0)
+    if(H5C_flush_cache(f, dxpl_id, H5C__FLUSH_MARKED_ENTRIES_FLAG | H5C__FLUSH_IGNORE_PROTECTED_FLAG) < 0)
         HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "Can't flush cache")
 
 done:
@@ -9929,7 +9842,7 @@ H5C_verify_tag(int id, haddr_t tag)
          * constraints are met. */
 
         /* Superblock */
-        if(id == H5AC_SUPERBLOCK_ID) {
+        if((id == H5AC_SUPERBLOCK_ID) || (id == H5AC_DRVRINFO_ID)) {
             if(tag != H5AC__SUPERBLOCK_TAG)
                 HGOTO_ERROR(H5E_CACHE, H5E_CANTTAG, FAIL, "superblock not tagged with H5AC__SUPERBLOCK_TAG")
         }
@@ -10001,10 +9914,9 @@ H5C_retag_copied_metadata(H5C_t * cache_ptr, haddr_t metadata_tag)
 
         next_entry_ptr = cache_ptr->index[u];
         while(next_entry_ptr != NULL) {
-            if(cache_ptr->index[u] != NULL) {
+            if(cache_ptr->index[u] != NULL)
                 if((cache_ptr->index[u])->tag == H5AC__COPIED_TAG)
                     (cache_ptr->index[u])->tag = metadata_tag;
-            } /* end if */
 
             next_entry_ptr = next_entry_ptr->ht_next;
         } /* end while */
diff --git a/src/H5Cmpio.c b/src/H5Cmpio.c
new file mode 100644
index 0000000..ec34285
--- /dev/null
+++ b/src/H5Cmpio.c
@@ -0,0 +1,1220 @@
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * Copyright by The HDF Group.                                               *
+ * Copyright by the Board of Trustees of the University of Illinois.         *
+ * All rights reserved.                                                      *
+ *                                                                           *
+ * This file is part of HDF5.  The full HDF5 copyright notice, including     *
+ * terms governing use, modification, and redistribution, is contained in    *
+ * the files COPYING and Copyright.html.  COPYING can be found at the root   *
+ * of the source code distribution tree; Copyright.html can be found at the  *
+ * root level of an installed copy of the electronic HDF5 document set and   *
+ * is linked from the top-level documents page.  It can also be found at     *
+ * http://hdfgroup.org/HDF5/doc/Copyright.html.  If you do not have          *
+ * access to either file, you may request a copy from help@hdfgroup.org.     *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+/*-------------------------------------------------------------------------
+ *
+ * Created:     H5Cmpio.c
+ *              June 20 2015
+ *              Quincey Koziol
+ *
+ * Purpose:     Functions in this file implement support for parallel I/O for
+ *		generic cache code.
+ *
+ *-------------------------------------------------------------------------
+ */
+
+/****************/
+/* Module Setup */
+/****************/
+
+#define H5C_PACKAGE		/*suppress error about including H5Cpkg   */
+#define H5F_PACKAGE		/*suppress error about including H5Fpkg	  */
+
+
+/***********/
+/* Headers */
+/***********/
+#include "H5private.h"		/* Generic Functions			*/
+#include "H5ACprivate.h"        /* Metadata cache                       */
+#include "H5Cpkg.h"		/* Cache				*/
+#include "H5Eprivate.h"		/* Error handling		  	*/
+#include "H5Fpkg.h"		/* Files				*/
+#include "H5Iprivate.h"		/* IDs			  		*/
+#include "H5MMprivate.h"	/* Memory management			*/
+
+
+#ifdef H5_HAVE_PARALLEL
+
+/****************/
+/* Local Macros */
+/****************/
+#define H5C_APPLY_CANDIDATE_LIST__DEBUG 0
+
+
+/******************/
+/* Local Typedefs */
+/******************/
+
+
+/********************/
+/* Local Prototypes */
+/********************/
+
+
+/*********************/
+/* Package Variables */
+/*********************/
+
+
+/*****************************/
+/* Library Private Variables */
+/*****************************/
+
+
+/*******************/
+/* Local Variables */
+/*******************/
+
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5C_apply_candidate_list
+ *
+ * Purpose:     Apply the supplied candidate list.
+ *
+ *		We used to do this by simply having each process write 
+ *		every mpi_size-th entry in the candidate list, starting 
+ *		at index mpi_rank, and mark all the others clean.  
+ *
+ *		However, this can cause unnecessary contention in a file 
+ *		system by increasing the number of processes writing to 
+ *		adjacent locations in the HDF5 file.
+ *
+ *		To attempt to minimize this, we now arange matters such 
+ *		that each process writes n adjacent entries in the 
+ *		candidate list, and marks all others clean.  We must do
+ *		this in such a fashion as to guarantee that each entry 
+ *		on the candidate list is written by exactly one process, 
+ *		and marked clean by all others.  
+ *
+ *		To do this, first construct a table mapping mpi_rank
+ *		to the index of the first entry in the candidate list to
+ *		be written by the process of that mpi_rank, and then use
+ *		the table to control which entries are written and which
+ *		are marked as clean as a function of the mpi_rank.
+ *
+ *		Note that the table must be identical on all processes, as
+ *		all see the same candidate list, mpi_size, and mpi_rank --
+ *		the inputs used to construct the table.  
+ *
+ *		We construct the table as follows.  Let:
+ *
+ *			n = num_candidates / mpi_size;
+ *
+ *			m = num_candidates % mpi_size;
+ *
+ *		Now allocate an array of integers of length mpi_size + 1, 
+ *		and call this array candidate_assignment_table. 
+ *
+ *		Conceptually, if the number of candidates is a multiple
+ *		of the mpi_size, we simply pass through the candidate list
+ *		and assign n entries to each process to flush, with the 
+ *		index of the first entry to flush in the location in 
+ *		the candidate_assignment_table indicated by the mpi_rank
+ *		of the process.  
+ *
+ *		In the more common case in which the candidate list isn't 
+ *		isn't a multiple of the mpi_size, we pretend it is, and 
+ *		give num_candidates % mpi_size processes one extra entry
+ *		each to make things work out.
+ *
+ *		Once the table is constructed, we determine the first and
+ *		last entry this process is to flush as follows:
+ *
+ *	 	first_entry_to_flush = candidate_assignment_table[mpi_rank]
+ *
+ *		last_entry_to_flush = 
+ *			candidate_assignment_table[mpi_rank + 1] - 1;
+ *		
+ *		With these values determined, we simply scan through the 
+ *		candidate list, marking all entries in the range 
+ *		[first_entry_to_flush, last_entry_to_flush] for flush,
+ *		and all others to be cleaned.
+ *
+ *		Finally, we scan the LRU from tail to head, flushing 
+ *		or marking clean the candidate entries as indicated.
+ *		If necessary, we scan the pinned list as well.
+ *
+ *		Note that this function will fail if any protected or 
+ *		clean entries appear on the candidate list.
+ *
+ *		This function is used in managing sync points, and 
+ *		shouldn't be used elsewhere.
+ *
+ * Return:      Success:        SUCCEED
+ *
+ *              Failure:        FAIL
+ *
+ * Programmer:  John Mainzer
+ *              3/17/10
+ *
+ * Changes:     Ported code to detect next entry status changes as the 
+ *              the result of a flush from the serial code in the scan of 
+ *              the LRU.  Also added code to detect and adapt to the 
+ *              removal from the cache of the next entry in the scan of 
+ *		the LRU.
+ *
+ *		Note that at present, all of these changes should not 
+ *		be required as the operations on entries as they are 
+ *		flushed that can cause these condiditions are not premitted
+ *		in the parallel case.  However, Quincey indicates that 
+ *		this may change, and thus has requested the modification.
+ *
+ *		Note the assert(FALSE) in the if statement whose body 
+ *		restarts the scan of the LRU.  As the body of the if 
+ *		statement should be unreachable, it should never be 
+ *		triggered until the constraints on the parallel case 
+ *		are relaxed.  Please remove the assertion at that time.
+ *
+ *		Also added warning on the Pinned Entry List scan, as it
+ *		is potentially subject to the same issue.  As there is 
+ *		no cognate of this scan in the serial code, I don't have
+ *		a fix to port to it.
+ *
+ *						JRM -- 4/10/19
+ *		
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5C_apply_candidate_list(H5F_t * f,
+                         hid_t dxpl_id,
+                         H5C_t * cache_ptr,
+                         int num_candidates,
+                         haddr_t * candidates_list_ptr,
+                         int mpi_rank,
+                         int mpi_size)
+{
+    hbool_t		restart_scan;
+    hbool_t		prev_is_dirty;
+    int                 i;
+    int			m;
+    int			n;
+    int			first_entry_to_flush;
+    int			last_entry_to_flush;
+    int			entries_to_clear = 0;
+    int			entries_to_flush = 0;
+    int			entries_to_flush_or_clear_last = 0;
+    int			entries_to_flush_collectively = 0;
+    int			entries_cleared = 0;
+    int			entries_flushed = 0;
+    int			entries_delayed = 0;
+    int			entries_flushed_or_cleared_last = 0;
+    int			entries_flushed_collectively = 0;
+    int			entries_examined = 0;
+    int			initial_list_len;
+    int               * candidate_assignment_table = NULL;
+    haddr_t		addr;
+    H5C_cache_entry_t *	clear_ptr = NULL;
+    H5C_cache_entry_t *	next_ptr = NULL;
+    H5C_cache_entry_t *	entry_ptr = NULL;
+    H5C_cache_entry_t *	flush_ptr = NULL;
+    H5C_cache_entry_t * delayed_ptr = NULL;
+#if H5C_DO_SANITY_CHECKS
+    haddr_t		last_addr;
+#endif /* H5C_DO_SANITY_CHECKS */
+#if H5C_APPLY_CANDIDATE_LIST__DEBUG
+    char		tbl_buf[1024];
+#endif /* H5C_APPLY_CANDIDATE_LIST__DEBUG */
+    herr_t              ret_value = SUCCEED;      /* Return value */
+
+    FUNC_ENTER_NOAPI(FAIL)
+
+    HDassert( cache_ptr != NULL );
+    HDassert( cache_ptr->magic == H5C__H5C_T_MAGIC );
+    HDassert( num_candidates > 0 );
+    HDassert( num_candidates <= cache_ptr->slist_len );
+    HDassert( candidates_list_ptr != NULL );
+    HDassert( 0 <= mpi_rank );
+    HDassert( mpi_rank < mpi_size );
+
+#if H5C_APPLY_CANDIDATE_LIST__DEBUG
+    HDfprintf(stdout, "%s:%d: setting up candidate assignment table.\n", 
+              FUNC, mpi_rank);
+    for ( i = 0; i < 1024; i++ ) tbl_buf[i] = '\0';
+    sprintf(&(tbl_buf[0]), "candidate list = ");
+    for ( i = 0; i < num_candidates; i++ )
+    {
+        sprintf(&(tbl_buf[HDstrlen(tbl_buf)]), " 0x%llx", 
+                (long long)(*(candidates_list_ptr + i)));
+    }
+    sprintf(&(tbl_buf[HDstrlen(tbl_buf)]), "\n");
+    HDfprintf(stdout, "%s", tbl_buf);
+#endif /* H5C_APPLY_CANDIDATE_LIST__DEBUG */
+
+    n = num_candidates / mpi_size;
+    m = num_candidates % mpi_size;
+    HDassert(n >= 0);
+
+    if(NULL == (candidate_assignment_table = (int *)H5MM_malloc(sizeof(int) * (size_t)(mpi_size + 1))))
+        HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed for candidate assignment table")
+
+    candidate_assignment_table[0] = 0;
+    candidate_assignment_table[mpi_size] = num_candidates;
+
+    if(m == 0) { /* mpi_size is an even divisor of num_candidates */
+        HDassert(n > 0);
+        for(i = 1; i < mpi_size; i++)
+            candidate_assignment_table[i] = candidate_assignment_table[i - 1] + n;
+    } /* end if */
+    else { 
+        for(i = 1; i <= m; i++)
+            candidate_assignment_table[i] = candidate_assignment_table[i - 1] + n + 1;
+
+        if(num_candidates < mpi_size) {
+            for(i = m + 1; i < mpi_size; i++)
+                candidate_assignment_table[i] = num_candidates;
+        } /* end if */
+        else {
+            for(i = m + 1; i < mpi_size; i++)
+                candidate_assignment_table[i] = candidate_assignment_table[i - 1] + n;
+        } /* end else */
+    } /* end else */
+    HDassert((candidate_assignment_table[mpi_size - 1] + n) == num_candidates);
+
+#if H5C_DO_SANITY_CHECKS
+    /* verify that the candidate assignment table has the expected form */
+    for ( i = 1; i < mpi_size - 1; i++ ) 
+    {
+        int a, b;
+
+        a = candidate_assignment_table[i] - candidate_assignment_table[i - 1];
+        b = candidate_assignment_table[i + 1] - candidate_assignment_table[i];
+
+        HDassert( n + 1 >= a );
+        HDassert( a >= b );
+        HDassert( b >= n );
+    }
+#endif /* H5C_DO_SANITY_CHECKS */
+
+    first_entry_to_flush = candidate_assignment_table[mpi_rank];
+    last_entry_to_flush = candidate_assignment_table[mpi_rank + 1] - 1;
+
+#if H5C_APPLY_CANDIDATE_LIST__DEBUG
+    for ( i = 0; i < 1024; i++ )
+        tbl_buf[i] = '\0';
+    sprintf(&(tbl_buf[0]), "candidate assignment table = ");
+    for(i = 0; i <= mpi_size; i++)
+        sprintf(&(tbl_buf[HDstrlen(tbl_buf)]), " %d", candidate_assignment_table[i]);
+    sprintf(&(tbl_buf[HDstrlen(tbl_buf)]), "\n");
+    HDfprintf(stdout, "%s", tbl_buf);
+
+    HDfprintf(stdout, "%s:%d: flush entries [%d, %d].\n", 
+              FUNC, mpi_rank, first_entry_to_flush, last_entry_to_flush);
+
+    HDfprintf(stdout, "%s:%d: marking entries.\n", FUNC, mpi_rank);
+#endif /* H5C_APPLY_CANDIDATE_LIST__DEBUG */
+
+    for(i = 0; i < num_candidates; i++) {
+        addr = candidates_list_ptr[i];
+        HDassert( H5F_addr_defined(addr) );
+
+#if H5C_DO_SANITY_CHECKS
+        if ( i > 0 ) {
+            if ( last_addr == addr ) {
+                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Duplicate entry in cleaned list.\n")
+            } else if ( last_addr > addr ) {
+                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "candidate list not sorted.\n")
+            }
+        }
+
+        last_addr = addr;
+#endif /* H5C_DO_SANITY_CHECKS */
+
+        H5C__SEARCH_INDEX(cache_ptr, addr, entry_ptr, FAIL)
+        if(entry_ptr == NULL) {
+            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Listed candidate entry not in cache?!?!?.")
+        } else if(!entry_ptr->is_dirty) {
+            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Listed entry not dirty?!?!?.")
+        } else if ( entry_ptr->is_protected ) {
+            /* For now at least, we can't deal with protected entries.
+             * If we encounter one, scream and die.  If it becomes an
+             * issue, we should be able to work around this. 
+             */
+            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Listed entry is protected?!?!?.")
+        } else {
+            /* determine whether the entry is to be cleared or flushed,
+             * and mark it accordingly.  We will scan the protected and 
+             * pinned list shortly, and clear or flush according to these
+             * markings.  
+             */
+            if((i >= first_entry_to_flush) && (i <= last_entry_to_flush)) {
+                entries_to_flush++;
+                entry_ptr->flush_immediately = TRUE;
+            } /* end if */
+            else {
+                entries_to_clear++;
+                entry_ptr->clear_on_unprotect = TRUE;
+            } /* end else */
+        } /* end else */
+    } /* end for */
+
+#if H5C_APPLY_CANDIDATE_LIST__DEBUG
+    HDfprintf(stdout, "%s:%d: num candidates/to clear/to flush = %d/%d/%d.\n", 
+              FUNC, mpi_rank, (int)num_candidates, (int)entries_to_clear,
+              (int)entries_to_flush);
+#endif /* H5C_APPLY_CANDIDATE_LIST__DEBUG */
+
+
+    /* We have now marked all the entries on the candidate list for 
+     * either flush or clear -- now scan the LRU and the pinned list
+     * for these entries and do the deed.
+     *
+     * Note that we are doing things in this round about manner so as
+     * to preserve the order of the LRU list to the best of our ability.
+     * If we don't do this, my experiments indicate that we will have a
+     * noticably poorer hit ratio as a result.
+     */
+
+#if H5C_APPLY_CANDIDATE_LIST__DEBUG
+    HDfprintf(stdout, "%s:%d: scanning LRU list. len = %d.\n", FUNC, mpi_rank,
+              (int)(cache_ptr->LRU_list_len));
+#endif /* H5C_APPLY_CANDIDATE_LIST__DEBUG */
+
+    /* ===================================================================== *
+     * Now scan the LRU and PEL lists, flushing or clearing entries as
+     * needed.
+     *
+     * The flush_me_last and flush_me_collectively flags may dictate how or
+     * when some entries can be flushed, and should be addressed here.
+     * However, in their initial implementation, these flags only apply to the
+     * superblock, so there's only a relatively small change to this function
+     * to account for this one case where they come into play. If these flags
+     * are ever expanded upon, this function and the following flushing steps
+     * should be reworked to account for additional cases.
+     * ===================================================================== */
+
+    HDassert(entries_to_flush >= 0);
+
+    restart_scan = FALSE;
+    entries_examined = 0;
+    initial_list_len = cache_ptr->LRU_list_len;
+    entry_ptr = cache_ptr->LRU_tail_ptr;
+
+    /* Examine each entry in the LRU list */
+    while ( ( entry_ptr != NULL ) 
+            && 
+            ( entries_examined <= (entries_to_flush + 1) * initial_list_len ) 
+            &&
+            ( (entries_cleared + entries_flushed) < num_candidates ) ) {
+
+        if ( entry_ptr->prev != NULL )
+            prev_is_dirty = entry_ptr->prev->is_dirty;
+
+        /* If this process needs to clear this entry. */
+        if(entry_ptr->clear_on_unprotect) {
+
+            HDassert(entry_ptr->is_dirty);
+
+            next_ptr = entry_ptr->next; 
+            entry_ptr->clear_on_unprotect = FALSE;
+            clear_ptr = entry_ptr;
+            entry_ptr = entry_ptr->prev;
+            entries_cleared++;
+
+#if ( H5C_APPLY_CANDIDATE_LIST__DEBUG > 1 )
+    HDfprintf(stdout, "%s:%d: clearing 0x%llx.\n", FUNC, mpi_rank,
+              (long long)clear_ptr->addr);
+#endif /* H5C_APPLY_CANDIDATE_LIST__DEBUG */
+
+	    /* No need to check for the next entry in the scan being 
+             * removed from the cache, as this call to H5C__flush_single_entry()
+             * will not call either the pre_serialize or serialize callbacks.
+             */
+
+            if(H5C__flush_single_entry(f, dxpl_id, clear_ptr, H5C__FLUSH_CLEAR_ONLY_FLAG | H5C__DEL_FROM_SLIST_ON_DESTROY_FLAG, NULL) < 0)
+                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't clear entry.")
+        } /* end if */
+
+        /* Else, if this process needs to flush this entry. */
+        else if (entry_ptr->flush_immediately) {
+
+	    HDassert(entry_ptr->is_dirty);
+
+            next_ptr = entry_ptr->next; 
+            entry_ptr->flush_immediately = FALSE;
+            flush_ptr = entry_ptr;
+            entry_ptr = entry_ptr->prev;
+            entries_flushed++;
+
+#if ( H5C_APPLY_CANDIDATE_LIST__DEBUG > 1 )
+    HDfprintf(stdout, "%s:%d: flushing 0x%llx.\n", FUNC, mpi_rank,
+              (long long)flush_ptr->addr);
+#endif /* H5C_APPLY_CANDIDATE_LIST__DEBUG */
+
+            /* reset entries_removed_counter and
+             * last_entry_removed_ptr prior to the call to
+             * H5C__flush_single_entry() so that we can spot
+             * unexpected removals of entries from the cache,
+             * and set the restart_scan flag if proceeding
+             * would be likely to cause us to scan an entry
+             * that is no longer in the cache.
+             *
+             * Note that as of this writing (April 2015) this 
+             * case cannot occur in the parallel case.  However 
+             * Quincey is making noises about changing this, hence 
+             * the insertion of this test.
+             *
+             * Note also that there is no test code to verify 
+             * that this code actually works (although similar code
+             * in the serial version exists and is tested).  
+             * 
+             * Implementing a test will likely require implementing
+             * flush op like facilities in the parallel tests.  At
+             * a guess this will not be terribly painful, but it 
+             * will take a bit of time.
+             */
+            cache_ptr->entries_removed_counter = 0;
+            cache_ptr->last_entry_removed_ptr  = NULL;
+
+            if(H5C__flush_single_entry(f, dxpl_id, flush_ptr, H5C__DEL_FROM_SLIST_ON_DESTROY_FLAG, NULL) < 0)
+                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't flush entry.")
+
+            if ( ( cache_ptr->entries_removed_counter > 1 ) ||
+                 ( cache_ptr->last_entry_removed_ptr == entry_ptr ) )
+
+                restart_scan = TRUE;
+
+        } /* end else-if */
+
+        /* Otherwise, no action to be taken on this entry. Grab the next. */
+        else {
+            entry_ptr = entry_ptr->prev;
+
+            if ( entry_ptr != NULL )
+                next_ptr = entry_ptr->next; 
+
+        } /* end else */
+
+        if ( ( entry_ptr != NULL ) 
+             &&
+             ( ( restart_scan )
+               ||
+               ( entry_ptr->is_dirty != prev_is_dirty )
+               ||
+               ( entry_ptr->next != next_ptr )
+               ||
+               ( entry_ptr->is_protected )
+               ||
+               ( entry_ptr->is_pinned ) 
+             ) 
+           ) {
+
+            /* something has happened to the LRU -- start over
+             * from the tail.
+             *
+             * Recall that this code should be un-reachable at present,
+             * as all the operations by entries on flush that could cause
+             * it to be reachable are disallowed in the parallel case at
+             * present.  Hence the following assertion which should be 
+             * removed if the above changes.
+             */
+
+	    HDassert( ! restart_scan );
+            HDassert( entry_ptr->is_dirty == prev_is_dirty );
+            HDassert( entry_ptr->next == next_ptr );
+            HDassert( ! entry_ptr->is_protected );
+            HDassert( ! entry_ptr->is_pinned );
+
+            HDassert(FALSE); /* see comment above */
+
+            restart_scan = FALSE;
+            entry_ptr = cache_ptr->LRU_tail_ptr;
+/* 
+	    H5C__UPDATE_STATS_FOR_LRU_SCAN_RESTART(cache_ptr)
+*/
+        }
+
+        entries_examined++;
+    } /* end while */
+
+#if H5C_APPLY_CANDIDATE_LIST__DEBUG
+    HDfprintf(stdout, "%s:%d: entries examined/cleared/flushed = %d/%d/%d.\n",
+              FUNC, mpi_rank, entries_examined,
+              entries_cleared, entries_flushed);
+#endif /* H5C_APPLY_CANDIDATE_LIST__DEBUG */
+
+    /* It is also possible that some of the cleared entries are on the
+     * pinned list.  Must scan that also.
+     *
+     * WARNING:
+     *
+     *	As we now allow unpinning, and removal of other entries as a side 
+     *  effect of flushing an entry, it is possible that the next entry
+     *  in a PEL scan could either be no longer pinned, or no longer in
+     *  the cache by the time we get to it.
+     *
+     *  At present, this is not possible in this case, as we disallow such
+     *  operations in the parallel version of the library.  However, Quincey
+     *  has been making noises about relaxing this.  If and when he does,
+     *  we have a potential problem here.
+     *
+     *  The same issue exists in the serial cache, and there are tests 
+     *  to detect this problem when it occurs, and adjust to it.  As seen
+     *  above in the LRU scan, I have ported such tests to the parallel 
+     *  code where a close cognate exists in the serial code.  
+     *
+     *  I haven't done so here, as there are no PEL scans where the problem
+     *  can occur in the serial code.  Needless to say, this will have to 
+     *  be repaired if the constraints on pre_serialize and serialize 
+     *  callbacks are relaxed in the parallel version of the metadata cache.
+     *
+     *						JRM -- 4/1/15
+     */
+
+#if H5C_APPLY_CANDIDATE_LIST__DEBUG
+    HDfprintf(stdout, "%s:%d: scanning pinned entry list. len = %d\n",
+             FUNC, mpi_rank, (int)(cache_ptr->pel_len));
+#endif /* H5C_APPLY_CANDIDATE_LIST__DEBUG */
+
+    entry_ptr = cache_ptr->pel_head_ptr;
+    while((entry_ptr != NULL) &&
+          ((entries_cleared + entries_flushed + entries_delayed)
+            < num_candidates)) {
+
+        /* If entry is marked for flush or for clear */
+        if((entry_ptr->clear_on_unprotect||entry_ptr->flush_immediately)) {
+
+            /* If this entry needs to be flushed last */
+            if (entry_ptr->flush_me_last) {
+
+                /* At this time, only the superblock supports being
+                   flushed last. Conveniently, it also happens to be the only
+                   entry that supports being flushed collectively, as well. Also
+                   conveniently, it's always pinned, so we only need to check
+                   for it while scanning the PEL here. Finally, it's never
+                   included in a candidate list that excludes other dirty
+                   entries in a cache, so we can handle this relatively simple
+                   case here.
+                   
+                   For now, this function asserts this and saves the entry
+                   to flush it after scanning the rest of the PEL list.
+
+                   If there are ever more entries that either need to be
+                   flushed last and/or flushed collectively, this whole routine
+                   will need to be reworked to handle all additional cases. As
+                   it is the simple case of a single pinned entry needing
+                   flushed last and collectively is just a minor addition to
+                   this routine, but signficantly buffing up the usage of
+                   flush_me_last or flush_me_collectively will require a more
+                   intense rework of this function and potentially the function
+                   of candidate lists as a whole. */
+
+                HDassert(entry_ptr->flush_me_collectively);
+                entries_to_flush_or_clear_last++;
+                entries_to_flush_collectively++;
+                HDassert(entries_to_flush_or_clear_last == 1);
+                HDassert(entries_to_flush_collectively == 1);
+
+                /* Delay the entry. It will be flushed later. */
+                delayed_ptr = entry_ptr;
+                entries_delayed++;
+                HDassert(entries_delayed == 1);
+
+            } /* end if */
+
+            /* Else, this process needs to clear this entry. */
+            else if (entry_ptr->clear_on_unprotect) {
+                HDassert(!entry_ptr->flush_immediately);
+                entry_ptr->clear_on_unprotect = FALSE;
+                clear_ptr = entry_ptr;
+                entry_ptr = entry_ptr->next;
+                entries_cleared++;
+
+#if ( H5C_APPLY_CANDIDATE_LIST__DEBUG > 1 )
+            HDfprintf(stdout, "%s:%d: clearing 0x%llx.\n", FUNC, mpi_rank,
+                      (long long)clear_ptr->addr);
+#endif /* H5C_APPLY_CANDIDATE_LIST__DEBUG */
+
+                if(H5C__flush_single_entry(f, dxpl_id, clear_ptr, H5C__FLUSH_CLEAR_ONLY_FLAG | H5C__DEL_FROM_SLIST_ON_DESTROY_FLAG, NULL) < 0)
+                    HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't clear entry.")
+            } /* end else-if */
+
+            /* Else, if this process needs to independently flush this entry. */
+            else if (entry_ptr->flush_immediately) {
+                entry_ptr->flush_immediately = FALSE;
+                flush_ptr = entry_ptr;
+                entry_ptr = entry_ptr->next;
+                entries_flushed++;
+
+#if ( H5C_APPLY_CANDIDATE_LIST__DEBUG > 1 )
+                HDfprintf(stdout, "%s:%d: flushing 0x%llx.\n", FUNC, mpi_rank,
+                      (long long)flush_ptr->addr);
+#endif /* H5C_APPLY_CANDIDATE_LIST__DEBUG */
+
+                if(H5C__flush_single_entry(f, dxpl_id, flush_ptr, H5C__DEL_FROM_SLIST_ON_DESTROY_FLAG, NULL) < 0)
+                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't clear entry.")
+            } /* end else-if */
+        } /* end if */
+
+        /* Otherwise, this entry is not marked for flush or clear. Grab the next. */
+        else {
+            entry_ptr = entry_ptr->next;
+        } /* end else */
+
+    } /* end while */
+
+#if H5C_APPLY_CANDIDATE_LIST__DEBUG
+    HDfprintf(stdout,
+              "%s:%d: pel entries examined/cleared/flushed = %d/%d/%d.\n",
+              FUNC, mpi_rank, entries_examined,
+              entries_cleared, entries_flushed);
+    HDfprintf(stdout, "%s:%d: done.\n", FUNC, mpi_rank);
+
+    HDfsync(stdout);
+#endif /* H5C_APPLY_CANDIDATE_LIST__DEBUG */
+
+    /* ====================================================================== *
+     * Now, handle all delayed entries.                                       *
+     *                                                                        *
+     * This can *only* be the superblock at this time, so it's relatively     *
+     * easy to deal with. We're collectively flushing the entry saved from    *
+     * above. This will need to be handled differently if there are ever more *
+     * than one entry needing this special treatment.)                        *
+     * ====================================================================== */
+
+    if (delayed_ptr) {
+
+        if (delayed_ptr->clear_on_unprotect) {
+            entry_ptr->clear_on_unprotect = FALSE;
+            entries_cleared++;
+        } else if (delayed_ptr->flush_immediately) {
+            entry_ptr->flush_immediately = FALSE;
+            entries_flushed++;
+        } /* end if */
+
+        if(H5C__flush_single_entry(f, dxpl_id, delayed_ptr, H5C__DEL_FROM_SLIST_ON_DESTROY_FLAG, NULL) < 0)
+            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't flush entry collectively.")
+
+        entries_flushed_collectively++;
+        entries_flushed_or_cleared_last++;
+    } /* end if */
+
+    /* ====================================================================== *
+     * Finished flushing everything.                                          *
+     * ====================================================================== */
+
+    HDassert((entries_flushed == entries_to_flush));
+    HDassert((entries_cleared == entries_to_clear));
+    HDassert((entries_flushed_or_cleared_last == entries_to_flush_or_clear_last));
+    HDassert((entries_flushed_collectively == entries_to_flush_collectively));
+    
+    if((entries_flushed != entries_to_flush) || 
+       (entries_cleared != entries_to_clear) ||
+       (entries_flushed_or_cleared_last != entries_to_flush_or_clear_last) ||
+       (entries_flushed_collectively != entries_to_flush_collectively))
+        HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "entry count mismatch.")
+
+done:
+    if(candidate_assignment_table != NULL)
+        candidate_assignment_table = (int *)H5MM_xfree((void *)candidate_assignment_table);
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5C_apply_candidate_list() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5C_construct_candidate_list__clean_cache
+ *
+ * Purpose:     Construct the list of entries that should be flushed to 
+ *		clean all entries in the cache.
+ *
+ *		This function is used in managing sync points, and 
+ *		shouldn't be used elsewhere.
+ *
+ * Return:      Success:        SUCCEED
+ *
+ *              Failure:        FAIL
+ *
+ * Programmer:  John Mainzer
+ *              3/17/10
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5C_construct_candidate_list__clean_cache(H5C_t * cache_ptr)
+{
+    size_t              space_needed;
+    herr_t              ret_value = SUCCEED;      /* Return value */
+
+    FUNC_ENTER_NOAPI(FAIL)
+
+    HDassert( cache_ptr != NULL );
+    HDassert( cache_ptr->magic == H5C__H5C_T_MAGIC );
+
+    /* As a sanity check, set space needed to the size of the skip list.
+     * This should be the sum total of the sizes of all the dirty entries
+     * in the metadata cache.
+     */
+    space_needed = cache_ptr->slist_size;
+
+    /* Recall that while we shouldn't have any protected entries at this
+     * point, it is possible that some dirty entries may reside on the
+     * pinned list at this point.
+     */
+    HDassert( cache_ptr->slist_size <= 
+              (cache_ptr->dLRU_list_size + cache_ptr->pel_size) );
+    HDassert( cache_ptr->slist_len  <= 
+              (cache_ptr->dLRU_list_len + cache_ptr->pel_len) );
+
+    if(space_needed > 0) { /* we have work to do */
+        H5C_cache_entry_t *entry_ptr;
+        int     nominated_entries_count = 0;
+        size_t  nominated_entries_size = 0;
+        haddr_t	nominated_addr;
+
+        HDassert( cache_ptr->slist_len > 0 );
+
+        /* Scan the dirty LRU list from tail forward and nominate sufficient
+         * entries to free up the necessary space. 
+         */
+        entry_ptr = cache_ptr->dLRU_tail_ptr;
+        while((nominated_entries_size < space_needed) &&
+                (nominated_entries_count < cache_ptr->slist_len) &&
+                (entry_ptr != NULL)) {
+            HDassert( ! (entry_ptr->is_protected) );
+            HDassert( ! (entry_ptr->is_read_only) );
+            HDassert( entry_ptr->ro_ref_count == 0 );
+            HDassert( entry_ptr->is_dirty );
+            HDassert( entry_ptr->in_slist );
+
+            nominated_addr = entry_ptr->addr;
+            if(H5AC_add_candidate((H5AC_t *)cache_ptr, nominated_addr) < 0)
+                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "H5AC_add_candidate() failed(1).")
+
+            nominated_entries_size += entry_ptr->size;
+            nominated_entries_count++;
+            entry_ptr = entry_ptr->aux_prev;
+        } /* end while */
+        HDassert( entry_ptr == NULL );
+
+        /* it is possible that there are some dirty entries on the 
+         * protected entry list as well -- scan it too if necessary
+         */
+        entry_ptr = cache_ptr->pel_head_ptr;
+        while((nominated_entries_size < space_needed) &&
+                (nominated_entries_count < cache_ptr->slist_len) &&
+                (entry_ptr != NULL)) {
+            if(entry_ptr->is_dirty) {
+                HDassert( ! (entry_ptr->is_protected) );
+                HDassert( ! (entry_ptr->is_read_only) );
+                HDassert( entry_ptr->ro_ref_count == 0 );
+                HDassert( entry_ptr->is_dirty );
+                HDassert( entry_ptr->in_slist );
+
+                nominated_addr = entry_ptr->addr;
+                if(H5AC_add_candidate((H5AC_t *)cache_ptr, nominated_addr) < 0)
+                    HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "H5AC_add_candidate() failed(2).")
+
+                nominated_entries_size += entry_ptr->size;
+                nominated_entries_count++;
+            } /* end if */
+
+            entry_ptr = entry_ptr->next;
+        } /* end while */
+
+        HDassert( nominated_entries_count == cache_ptr->slist_len );
+        HDassert( nominated_entries_size == space_needed );
+    } /* end if */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5C_construct_candidate_list__clean_cache() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5C_construct_candidate_list__min_clean
+ *
+ * Purpose:     Construct the list of entries that should be flushed to 
+ *		get the cache back within its min clean constraints.
+ *
+ *		This function is used in managing sync points, and 
+ *		shouldn't be used elsewhere.
+ *
+ * Return:      Success:        SUCCEED
+ *
+ *              Failure:        FAIL
+ *
+ * Programmer:  John Mainzer
+ *              3/17/10
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5C_construct_candidate_list__min_clean(H5C_t * cache_ptr)
+{
+    size_t              space_needed = 0;
+    herr_t              ret_value = SUCCEED;      /* Return value */
+
+    FUNC_ENTER_NOAPI(FAIL)
+
+    HDassert( cache_ptr != NULL );
+    HDassert( cache_ptr->magic == H5C__H5C_T_MAGIC );
+
+    /* compute the number of bytes (if any) that must be flushed to get the 
+     * cache back within its min clean constraints.
+     */
+    if(cache_ptr->max_cache_size > cache_ptr->index_size) {
+        if(((cache_ptr->max_cache_size - cache_ptr->index_size) +
+               cache_ptr->cLRU_list_size) >= cache_ptr->min_clean_size)
+            space_needed = 0;
+        else
+            space_needed = cache_ptr->min_clean_size -
+                ((cache_ptr->max_cache_size - cache_ptr->index_size) +
+                 cache_ptr->cLRU_list_size);
+    } /* end if */
+    else {
+        if(cache_ptr->min_clean_size <= cache_ptr->cLRU_list_size)
+           space_needed = 0;
+        else
+            space_needed = cache_ptr->min_clean_size -
+                           cache_ptr->cLRU_list_size;
+    } /* end else */
+
+    if(space_needed > 0) { /* we have work to do */
+        H5C_cache_entry_t *entry_ptr;
+        int    nominated_entries_count = 0;
+        size_t nominated_entries_size = 0;
+
+        HDassert( cache_ptr->slist_len > 0 );
+
+        /* Scan the dirty LRU list from tail forward and nominate sufficient
+         * entries to free up the necessary space. 
+         */
+        entry_ptr = cache_ptr->dLRU_tail_ptr;
+        while((nominated_entries_size < space_needed) &&
+                (nominated_entries_count < cache_ptr->slist_len) &&
+                (entry_ptr != NULL) &&
+                (!entry_ptr->flush_me_last)) {
+            haddr_t		nominated_addr;
+
+            HDassert( ! (entry_ptr->is_protected) );
+            HDassert( ! (entry_ptr->is_read_only) );
+            HDassert( entry_ptr->ro_ref_count == 0 );
+            HDassert( entry_ptr->is_dirty );
+            HDassert( entry_ptr->in_slist );
+
+            nominated_addr = entry_ptr->addr;
+            if(H5AC_add_candidate((H5AC_t *)cache_ptr, nominated_addr) < 0)
+                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "H5AC_add_candidate() failed.")
+
+            nominated_entries_size += entry_ptr->size;
+            nominated_entries_count++;
+            entry_ptr = entry_ptr->aux_prev;
+        } /* end while */
+        HDassert( nominated_entries_count <= cache_ptr->slist_len );
+        HDassert( nominated_entries_size >= space_needed );
+    } /* end if */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5C_construct_candidate_list__min_clean() */
+
+
+/*-------------------------------------------------------------------------
+ *
+ * Function:    H5C_mark_entries_as_clean
+ *
+ * Purpose:     When the H5C code is used to implement the metadata caches
+ *		in PHDF5, only the cache with MPI_rank 0 is allowed to
+ *		actually write entries to disk -- all other caches must
+ *		retain dirty entries until they are advised that the
+ *		entries are clean.
+ *
+ *		This function exists to allow the H5C code to receive these
+ *		notifications.
+ *
+ *		The function receives a list of entry base addresses
+ *		which must refer to dirty entries in the cache.  If any
+ *		of the entries are either clean or don't exist, the
+ *		function flags an error.
+ *
+ *		The function scans the list of entries and flushes all
+ *		those that are currently unprotected with the
+ *		H5C__FLUSH_CLEAR_ONLY_FLAG.  Those that are currently
+ *		protected are flagged for clearing when they are
+ *		unprotected.
+ *
+ * Return:      Non-negative on success/Negative on failure
+ *
+ * Programmer:  John Mainzer
+ *              7/5/05
+ *
+ * Changes:     Tidied up code, removeing some old commented out 
+ *		code that had been left in pending success of the 
+ *		new version.
+ *
+ *		Note that unlike H5C_apply_candidate_list(), 
+ *		H5C_mark_entries_as_clean() makes all its calls to 
+ *		H6C_flush_single_entry() with the 
+ *		H5C__FLUSH_CLEAR_ONLY_FLAG set.  As a result, 
+ *		the pre_serialize() and serialize calls are not made.
+ *
+ *		This then implies that (assuming such actions were 
+ *		permitted in the parallel case) no loads, dirties, 
+ *		resizes, or removals of other entries can occur as 
+ *		a side effect of the flush.  Hence, there is no need
+ *		for the checks for entry removal / status change 
+ *		that I ported to H5C_apply_candidate_list().
+ *
+ *		However, if (in addition to allowing such operations
+ *		in the parallel case), we allow such operations outside
+ *		of the pre_serialize / serialize routines, this may 
+ *		cease to be the case -- requiring a review of this 
+ *		function.
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5C_mark_entries_as_clean(H5F_t *  f,
+                          hid_t     dxpl_id,
+                          int32_t   ce_array_len,
+                          haddr_t * ce_array_ptr)
+{
+    H5C_t *             cache_ptr;
+    int			entries_cleared;
+    int			entries_examined;
+    int                 i;
+    int			initial_list_len;
+    haddr_t		addr;
+#if H5C_DO_SANITY_CHECKS
+    int			pinned_entries_marked = 0;
+    int			protected_entries_marked = 0;
+    int			other_entries_marked = 0;
+    haddr_t		last_addr;
+#endif /* H5C_DO_SANITY_CHECKS */
+    H5C_cache_entry_t *	clear_ptr = NULL;
+    H5C_cache_entry_t *	entry_ptr = NULL;
+    herr_t		ret_value = SUCCEED;      /* Return value */
+
+    FUNC_ENTER_NOAPI(FAIL)
+
+    HDassert( f );
+    HDassert( f->shared );
+    cache_ptr = f->shared->cache;
+    HDassert( cache_ptr );
+    HDassert( cache_ptr->magic == H5C__H5C_T_MAGIC );
+
+    HDassert( ce_array_len > 0 );
+    HDassert( ce_array_ptr != NULL );
+
+#if H5C_DO_EXTREME_SANITY_CHECKS
+    if ( ( H5C_validate_protected_entry_list(cache_ptr) < 0 ) ||
+         ( H5C_validate_pinned_entry_list(cache_ptr) < 0 ) ||
+         ( H5C_validate_lru_list(cache_ptr) < 0 ) ) {
+
+        HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, \
+                    "an extreme sanity check failed on entry.\n");
+    }
+#endif /* H5C_DO_EXTREME_SANITY_CHECKS */
+
+    for ( i = 0; i < ce_array_len; i++ )
+    {
+        addr = ce_array_ptr[i];
+
+#if H5C_DO_SANITY_CHECKS
+        if ( i == 0 ) {
+
+            last_addr = addr;
+
+        } else {
+
+            if ( last_addr == addr ) {
+
+                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, \
+                            "Duplicate entry in cleaned list.\n");
+
+            } else if ( last_addr > addr ) {
+
+                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, \
+                            "cleaned list not sorted.\n");
+            }
+        }
+
+#if H5C_DO_EXTREME_SANITY_CHECKS
+        if ( ( H5C_validate_protected_entry_list(cache_ptr) < 0 ) ||
+             ( H5C_validate_pinned_entry_list(cache_ptr) < 0 ) ||
+             ( H5C_validate_lru_list(cache_ptr) < 0 ) ) {
+
+            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, \
+                        "an extreme sanity check failed in for loop.\n");
+        }
+#endif /* H5C_DO_EXTREME_SANITY_CHECKS */
+#endif /* H5C_DO_SANITY_CHECKS */
+
+        HDassert( H5F_addr_defined(addr) );
+
+        H5C__SEARCH_INDEX(cache_ptr, addr, entry_ptr, FAIL)
+
+        if ( entry_ptr == NULL ) {
+#if H5C_DO_SANITY_CHECKS
+	    HDfprintf(stdout,
+                  "H5C_mark_entries_as_clean: entry[%d] = %ld not in cache.\n",
+                      (int)i,
+                      (long)addr);
+#endif /* H5C_DO_SANITY_CHECKS */
+            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, \
+                        "Listed entry not in cache?!?!?.")
+
+        } else if ( ! entry_ptr->is_dirty ) {
+
+#if H5C_DO_SANITY_CHECKS
+	    HDfprintf(stdout,
+                      "H5C_mark_entries_as_clean: entry %ld is not dirty!?!\n",
+                      (long)addr);
+#endif /* H5C_DO_SANITY_CHECKS */
+            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, \
+                        "Listed entry not dirty?!?!?.")
+
+        } else {
+
+            /* Mark the entry to be cleared on unprotect.  We will
+             * scan the LRU list shortly, and clear all those entries
+             * not currently protected.
+             */
+            entry_ptr->clear_on_unprotect = TRUE;
+#if H5C_DO_SANITY_CHECKS
+	    if ( entry_ptr->is_protected ) {
+
+		protected_entries_marked++;
+
+	    } else if ( entry_ptr->is_pinned ) {
+
+		pinned_entries_marked++;
+
+	    } else {
+
+		other_entries_marked++;
+	    }
+#endif /* H5C_DO_SANITY_CHECKS */
+        }
+    }
+
+    /* Scan through the LRU list from back to front, and flush the
+     * entries whose clear_on_unprotect flags are set.  Observe that
+     * any protected entries will not be on the LRU, and therefore
+     * will not be flushed at this time.
+     *
+     * Note that unlike H5C_apply_candidate_list(), 
+     * H5C_mark_entries_as_clean() makes all its calls to 
+     * H6C_flush_single_entry() with the H5C__FLUSH_CLEAR_ONLY_FLAG 
+     * set.  As a result, the pre_serialize() and serialize calls are 
+     * not made.
+     *
+     * This then implies that (assuming such actions were 
+     * permitted in the parallel case) no loads, dirties, 
+     * resizes, or removals of other entries can occur as 
+     * a side effect of the flush.  Hence, there is no need
+     * for the checks for entry removal / status change 
+     * that I ported to H5C_apply_candidate_list().
+     *
+     * However, if (in addition to allowing such operations
+     * in the parallel case), we allow such operations outside
+     * of the pre_serialize / serialize routines, this may 
+     * cease to be the case -- requiring a review of this 
+     * point.
+     *					JRM -- 4/7/15
+     */
+
+    entries_cleared = 0;
+    entries_examined = 0;
+    initial_list_len = cache_ptr->LRU_list_len;
+    entry_ptr = cache_ptr->LRU_tail_ptr;
+
+    while ( ( entry_ptr != NULL ) &&
+            ( entries_examined <= initial_list_len ) &&
+            ( entries_cleared < ce_array_len ) )
+    {
+        if ( entry_ptr->clear_on_unprotect ) {
+
+            entry_ptr->clear_on_unprotect = FALSE;
+            clear_ptr = entry_ptr;
+            entry_ptr = entry_ptr->prev;
+            entries_cleared++;
+
+            if(H5C__flush_single_entry(f, dxpl_id, clear_ptr, H5C__FLUSH_CLEAR_ONLY_FLAG | H5C__DEL_FROM_SLIST_ON_DESTROY_FLAG, NULL) < 0)
+                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't clear entry.")
+        } else {
+
+            entry_ptr = entry_ptr->prev;
+        }
+        entries_examined++;
+    }
+
+#if H5C_DO_SANITY_CHECKS
+    HDassert( entries_cleared == other_entries_marked );
+#endif /* H5C_DO_SANITY_CHECKS */
+
+    /* It is also possible that some of the cleared entries are on the
+     * pinned list.  Must scan that also.
+     */
+
+    entry_ptr = cache_ptr->pel_head_ptr;
+
+    while ( entry_ptr != NULL )
+    {
+        if ( entry_ptr->clear_on_unprotect ) {
+
+            entry_ptr->clear_on_unprotect = FALSE;
+            clear_ptr = entry_ptr;
+            entry_ptr = entry_ptr->next;
+            entries_cleared++;
+
+            if(H5C__flush_single_entry(f, dxpl_id, clear_ptr, H5C__FLUSH_CLEAR_ONLY_FLAG | H5C__DEL_FROM_SLIST_ON_DESTROY_FLAG, NULL) < 0 )
+                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Can't clear entry.")
+        } else {
+
+            entry_ptr = entry_ptr->next;
+        }
+    }
+
+#if H5C_DO_SANITY_CHECKS
+    HDassert( entries_cleared == pinned_entries_marked + other_entries_marked );
+    HDassert( entries_cleared + protected_entries_marked == ce_array_len );
+#endif /* H5C_DO_SANITY_CHECKS */
+
+    HDassert( ( entries_cleared == ce_array_len ) ||
+              ( (ce_array_len - entries_cleared) <= cache_ptr->pl_len ) );
+
+#if H5C_DO_SANITY_CHECKS
+    i = 0;
+    entry_ptr = cache_ptr->pl_head_ptr;
+    while ( entry_ptr != NULL )
+    {
+        if ( entry_ptr->clear_on_unprotect ) {
+
+            i++;
+        }
+        entry_ptr = entry_ptr->next;
+    }
+    HDassert( (entries_cleared + i) == ce_array_len );
+#endif /* H5C_DO_SANITY_CHECKS */
+
+done:
+
+#if H5C_DO_EXTREME_SANITY_CHECKS
+    if ( ( H5C_validate_protected_entry_list(cache_ptr) < 0 ) ||
+         ( H5C_validate_pinned_entry_list(cache_ptr) < 0 ) ||
+         ( H5C_validate_lru_list(cache_ptr) < 0 ) ) {
+
+        HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, \
+                    "an extreme sanity check failed on exit.\n");
+    }
+#endif /* H5C_DO_EXTREME_SANITY_CHECKS */
+
+    FUNC_LEAVE_NOAPI(ret_value)
+
+} /* H5C_mark_entries_as_clean() */
+#endif /* H5_HAVE_PARALLEL */
+
diff --git a/src/H5Cpkg.h b/src/H5Cpkg.h
index 5df84cd..7d9d0f9 100644
--- a/src/H5Cpkg.h
+++ b/src/H5Cpkg.h
@@ -60,8 +60,6 @@
 /* Cache configuration settings */
 #define H5C__HASH_TABLE_LEN     (64 * 1024) /* must be a power of 2 */
 #define H5C__H5C_T_MAGIC	0x005CAC0E
-#define H5C__MAX_NUM_TYPE_IDS	27
-#define H5C__PREFIX_LEN		32
 
 /****************************************************************************
  *
@@ -573,6 +571,15 @@ if ( ( (entry_ptr) == NULL ) ||                                                \
 #define H5C__UPDATE_STATS_FOR_UNPIN(cache_ptr, entry_ptr) \
 	((cache_ptr)->unpins)[(entry_ptr)->type->id]++;
 
+#define H5C__UPDATE_STATS_FOR_SLIST_SCAN_RESTART(cache_ptr) \
+	((cache_ptr)->slist_scan_restarts)++;
+
+#define H5C__UPDATE_STATS_FOR_LRU_SCAN_RESTART(cache_ptr) \
+	((cache_ptr)->LRU_scan_restarts)++;
+
+#define H5C__UPDATE_STATS_FOR_HASH_BUCKET_SCAN_RESTART(cache_ptr) \
+	((cache_ptr)->hash_bucket_scan_restarts)++;
+
 #if H5C_COLLECT_CACHE_ENTRY_STATS
 
 #define H5C__RESET_CACHE_ENTRY_STATS(entry_ptr) \
@@ -586,7 +593,7 @@ if ( ( (entry_ptr) == NULL ) ||                                                \
 #define H5C__UPDATE_STATS_FOR_CLEAR(cache_ptr, entry_ptr)        \
 {                                                                \
     (((cache_ptr)->clears)[(entry_ptr)->type->id])++;            \
-    if ( (entry_ptr)->is_pinned )                                \
+    if((entry_ptr)->is_pinned)                                   \
         (((cache_ptr)->pinned_clears)[(entry_ptr)->type->id])++; \
     ((entry_ptr)->clears)++;                                     \
 }
@@ -599,9 +606,12 @@ if ( ( (entry_ptr) == NULL ) ||                                                \
     ((entry_ptr)->flushes)++;                                     \
 }
 
-#define H5C__UPDATE_STATS_FOR_EVICTION(cache_ptr, entry_ptr)             \
-{                                                                        \
-    (((cache_ptr)->evictions)[(entry_ptr)->type->id])++;                 \
+#define H5C__UPDATE_STATS_FOR_EVICTION(cache_ptr, entry_ptr, take_ownership) \
+{                                                                            \
+    if ( take_ownership )                                                    \
+        (((cache_ptr)->take_ownerships)[(entry_ptr)->type->id])++;           \
+    else                                                                     \
+        (((cache_ptr)->evictions)[(entry_ptr)->type->id])++;                 \
     if ( (entry_ptr)->accesses >                                         \
             ((cache_ptr)->max_accesses)[(entry_ptr)->type->id] )         \
         ((cache_ptr)->max_accesses)[(entry_ptr)->type->id] =             \
@@ -697,9 +707,9 @@ if ( ( (entry_ptr) == NULL ) ||                                                \
 
 #define H5C__UPDATE_STATS_FOR_CLEAR(cache_ptr, entry_ptr)         \
 {                                                                 \
-    if ( (entry_ptr)->is_pinned )                                 \
-        (((cache_ptr)->pinned_clears)[(entry_ptr)->type->id])++;  \
     (((cache_ptr)->clears)[(entry_ptr)->type->id])++;             \
+    if((entry_ptr)->is_pinned)                                    \
+        (((cache_ptr)->pinned_clears)[(entry_ptr)->type->id])++;  \
 }
 
 #define H5C__UPDATE_STATS_FOR_FLUSH(cache_ptr, entry_ptr)         \
@@ -709,8 +719,13 @@ if ( ( (entry_ptr) == NULL ) ||                                                \
         (((cache_ptr)->pinned_flushes)[(entry_ptr)->type->id])++; \
 }
 
-#define H5C__UPDATE_STATS_FOR_EVICTION(cache_ptr, entry_ptr)      \
-    (((cache_ptr)->evictions)[(entry_ptr)->type->id])++;
+#define H5C__UPDATE_STATS_FOR_EVICTION(cache_ptr, entry_ptr, take_ownership) \
+{                                                                            \
+    if ( take_ownership )                                                    \
+        (((cache_ptr)->take_ownerships)[(entry_ptr)->type->id])++;           \
+    else                                                                     \
+        (((cache_ptr)->evictions)[(entry_ptr)->type->id])++;                 \
+}
 
 #define H5C__UPDATE_STATS_FOR_INSERTION(cache_ptr, entry_ptr)        \
 {                                                                    \
@@ -780,10 +795,13 @@ if ( ( (entry_ptr) == NULL ) ||                                                \
 #define H5C__UPDATE_STATS_FOR_INSERTION(cache_ptr, entry_ptr)
 #define H5C__UPDATE_STATS_FOR_CLEAR(cache_ptr, entry_ptr)
 #define H5C__UPDATE_STATS_FOR_FLUSH(cache_ptr, entry_ptr)
-#define H5C__UPDATE_STATS_FOR_EVICTION(cache_ptr, entry_ptr)
+#define H5C__UPDATE_STATS_FOR_EVICTION(cache_ptr, entry_ptr, take_ownership)
 #define H5C__UPDATE_STATS_FOR_PROTECT(cache_ptr, entry_ptr, hit)
 #define H5C__UPDATE_STATS_FOR_PIN(cache_ptr, entry_ptr)
 #define H5C__UPDATE_STATS_FOR_UNPIN(cache_ptr, entry_ptr)
+#define H5C__UPDATE_STATS_FOR_SLIST_SCAN_RESTART(cache_ptr)
+#define H5C__UPDATE_STATS_FOR_LRU_SCAN_RESTART(cache_ptr)
+#define H5C__UPDATE_STATS_FOR_HASH_BUCKET_SCAN_RESTART(cache_ptr)
 
 #endif /* H5C_COLLECT_CACHE_STATS */
 
@@ -828,11 +846,25 @@ if ( ( (cache_ptr) == NULL ) ||                                         \
      ( H5C__HASH_FCN((entry_ptr)->addr) >= H5C__HASH_TABLE_LEN ) ||     \
      ( (cache_ptr)->index_size !=                                       \
        ((cache_ptr)->clean_index_size +                                 \
-	(cache_ptr)->dirty_index_size) ) ) {                            \
+	(cache_ptr)->dirty_index_size) ) ||                             \
+     ( (cache_ptr)->index_size < ((cache_ptr)->clean_index_size) ) ||   \
+     ( (cache_ptr)->index_size < ((cache_ptr)->dirty_index_size) ) ) {  \
     HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, fail_val,                        \
                "Pre HT insert SC failed")                               \
 }
 
+#define H5C__POST_HT_INSERT_SC(cache_ptr, fail_val)                     \
+if ( ( (cache_ptr) == NULL ) ||                                         \
+     ( (cache_ptr)->magic != H5C__H5C_T_MAGIC ) ||                      \
+     ( (cache_ptr)->index_size !=                                       \
+       ((cache_ptr)->clean_index_size +                                 \
+	(cache_ptr)->dirty_index_size) ) ||                             \
+     ( (cache_ptr)->index_size < ((cache_ptr)->clean_index_size) ) ||   \
+     ( (cache_ptr)->index_size < ((cache_ptr)->dirty_index_size) ) ) {  \
+    HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, fail_val,                        \
+               "Post HT insert SC failed")                              \
+}
+
 #define H5C__PRE_HT_REMOVE_SC(cache_ptr, entry_ptr)                     \
 if ( ( (cache_ptr) == NULL ) ||                                         \
      ( (cache_ptr)->magic != H5C__H5C_T_MAGIC ) ||                      \
@@ -853,10 +885,28 @@ if ( ( (cache_ptr) == NULL ) ||                                         \
        ( (entry_ptr)->ht_prev != NULL ) ) ||                            \
      ( (cache_ptr)->index_size !=                                       \
        ((cache_ptr)->clean_index_size +                                 \
-	(cache_ptr)->dirty_index_size) ) ) {                            \
+	(cache_ptr)->dirty_index_size) ) ||                             \
+     ( (cache_ptr)->index_size < ((cache_ptr)->clean_index_size) ) ||   \
+     ( (cache_ptr)->index_size < ((cache_ptr)->dirty_index_size) ) ) {  \
     HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Pre HT remove SC failed") \
 }
 
+#define H5C__POST_HT_REMOVE_SC(cache_ptr, entry_ptr)                     \
+if ( ( (cache_ptr) == NULL ) ||                                          \
+     ( (cache_ptr)->magic != H5C__H5C_T_MAGIC ) ||                       \
+     ( (entry_ptr) == NULL ) ||                                          \
+     ( ! H5F_addr_defined((entry_ptr)->addr) ) ||                        \
+     ( (entry_ptr)->size <= 0 ) ||                                       \
+     ( (entry_ptr)->ht_prev != NULL ) ||                                 \
+     ( (entry_ptr)->ht_prev != NULL ) ||                                 \
+     ( (cache_ptr)->index_size !=                                        \
+       ((cache_ptr)->clean_index_size +                                  \
+	(cache_ptr)->dirty_index_size) ) ||                              \
+     ( (cache_ptr)->index_size < ((cache_ptr)->clean_index_size) ) ||    \
+     ( (cache_ptr)->index_size < ((cache_ptr)->dirty_index_size) ) ) {   \
+    HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Post HT remove SC failed") \
+}
+
 /* (Keep in sync w/H5C_TEST__PRE_HT_SEARCH_SC macro in test/cache_common.h -QAK) */
 #define H5C__PRE_HT_SEARCH_SC(cache_ptr, Addr, fail_val)                    \
 if ( ( (cache_ptr) == NULL ) ||                                             \
@@ -915,6 +965,8 @@ if ( ( (cache_ptr) == NULL ) ||                                         \
      ( (cache_ptr)->index_size !=                                       \
        ((cache_ptr)->clean_index_size +                                 \
         (cache_ptr)->dirty_index_size) ) ||                             \
+     ( (cache_ptr)->index_size < ((cache_ptr)->clean_index_size) ) ||   \
+     ( (cache_ptr)->index_size < ((cache_ptr)->dirty_index_size) ) ||   \
      ( ( !( was_clean ) ||                                              \
 	    ( (cache_ptr)->clean_index_size < (old_size) ) ) &&         \
 	  ( ( (was_clean) ) ||                                          \
@@ -933,6 +985,8 @@ if ( ( (cache_ptr) == NULL ) ||                                           \
      ( (cache_ptr)->index_size !=                                         \
 	  ((cache_ptr)->clean_index_size +                                \
            (cache_ptr)->dirty_index_size) ) ||                            \
+     ( (cache_ptr)->index_size < ((cache_ptr)->clean_index_size) ) ||     \
+     ( (cache_ptr)->index_size < ((cache_ptr)->dirty_index_size) ) ||     \
      ( ( !((entry_ptr)->is_dirty ) ||                                     \
 	    ( (cache_ptr)->dirty_index_size < (new_size) ) ) &&           \
 	  ( ( ((entry_ptr)->is_dirty)  ) ||                               \
@@ -953,7 +1007,9 @@ if (                                                                          \
     ( (cache_ptr)->index_size < (entry_ptr)->size ) ||                        \
     ( (cache_ptr)->dirty_index_size < (entry_ptr)->size ) ||                  \
     ( (cache_ptr)->index_size !=                                              \
-       ((cache_ptr)->clean_index_size + (cache_ptr)->dirty_index_size) ) ) {  \
+       ((cache_ptr)->clean_index_size + (cache_ptr)->dirty_index_size) ) ||   \
+    ( (cache_ptr)->index_size < ((cache_ptr)->clean_index_size) ) ||          \
+    ( (cache_ptr)->index_size < ((cache_ptr)->dirty_index_size) ) ) {         \
     HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL,                                  \
                 "Pre HT update for entry clean SC failed")                    \
 }
@@ -968,21 +1024,27 @@ if (                                                                          \
     ( (cache_ptr)->index_size < (entry_ptr)->size ) ||                        \
     ( (cache_ptr)->clean_index_size < (entry_ptr)->size ) ||                  \
     ( (cache_ptr)->index_size !=                                              \
-       ((cache_ptr)->clean_index_size + (cache_ptr)->dirty_index_size) ) ) {  \
+       ((cache_ptr)->clean_index_size + (cache_ptr)->dirty_index_size) ) ||   \
+    ( (cache_ptr)->index_size < ((cache_ptr)->clean_index_size) ) ||          \
+    ( (cache_ptr)->index_size < ((cache_ptr)->dirty_index_size) ) ) {         \
     HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL,                                  \
                 "Pre HT update for entry dirty SC failed")                    \
 }
 
 #define H5C__POST_HT_UPDATE_FOR_ENTRY_CLEAN_SC(cache_ptr, entry_ptr)        \
-if ( (cache_ptr)->index_size !=                                             \
-       ((cache_ptr)->clean_index_size + (cache_ptr)->dirty_index_size) ) {  \
+if ( ( (cache_ptr)->index_size !=                                           \
+       ((cache_ptr)->clean_index_size + (cache_ptr)->dirty_index_size) ) || \
+     ( (cache_ptr)->index_size < ((cache_ptr)->clean_index_size) ) ||       \
+     ( (cache_ptr)->index_size < ((cache_ptr)->dirty_index_size) ) ) {      \
     HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL,                                \
                 "Post HT update for entry clean SC failed")                 \
 }
 
 #define H5C__POST_HT_UPDATE_FOR_ENTRY_DIRTY_SC(cache_ptr, entry_ptr)        \
-if ( (cache_ptr)->index_size !=                                             \
-       ((cache_ptr)->clean_index_size + (cache_ptr)->dirty_index_size) ) {  \
+if ( ( (cache_ptr)->index_size !=                                           \
+       ((cache_ptr)->clean_index_size + (cache_ptr)->dirty_index_size) ) || \
+     ( (cache_ptr)->index_size < ((cache_ptr)->clean_index_size) ) ||       \
+     ( (cache_ptr)->index_size < ((cache_ptr)->dirty_index_size) ) ) {      \
     HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL,                                \
                 "Post HT update for entry dirty SC failed")                 \
 }
@@ -990,7 +1052,9 @@ if ( (cache_ptr)->index_size !=                                             \
 #else /* H5C_DO_SANITY_CHECKS */
 
 #define H5C__PRE_HT_INSERT_SC(cache_ptr, entry_ptr, fail_val)
+#define H5C__POST_HT_INSERT_SC(cache_ptr, fail_val)
 #define H5C__PRE_HT_REMOVE_SC(cache_ptr, entry_ptr)
+#define H5C__POST_HT_REMOVE_SC(cache_ptr, entry_ptr)
 #define H5C__PRE_HT_SEARCH_SC(cache_ptr, Addr, fail_val)
 #define H5C__POST_SUC_HT_SEARCH_SC(cache_ptr, entry_ptr, Addr, k, fail_val)
 #define H5C__POST_HT_SHIFT_TO_FRONT(cache_ptr, entry_ptr, k, fail_val)
@@ -1026,9 +1090,10 @@ if ( (cache_ptr)->index_size !=                                             \
 	(cache_ptr)->clean_index_size += (entry_ptr)->size;  \
     if ((entry_ptr)->flush_me_last) {                        \
         (cache_ptr)->num_last_entries++;                     \
-        HDassert((cache_ptr)->num_last_entries == 1);        \
+        HDassert((cache_ptr)->num_last_entries <= 2);        \
     }                                                        \
     H5C__UPDATE_STATS_FOR_HT_INSERTION(cache_ptr)            \
+    H5C__POST_HT_INSERT_SC(cache_ptr, fail_val)              \
 }
 
 #define H5C__DELETE_FROM_INDEX(cache_ptr, entry_ptr)          \
@@ -1052,9 +1117,10 @@ if ( (cache_ptr)->index_size !=                                             \
 	(cache_ptr)->clean_index_size -= (entry_ptr)->size;   \
     if ((entry_ptr)->flush_me_last) {                         \
         (cache_ptr)->num_last_entries--;                      \
-        HDassert((cache_ptr)->num_last_entries == 0);         \
+        HDassert((cache_ptr)->num_last_entries <= 1);         \
     }                                                         \
     H5C__UPDATE_STATS_FOR_HT_DELETION(cache_ptr)              \
+    H5C__POST_HT_REMOVE_SC(cache_ptr, entry_ptr)              \
 }
 
 #define H5C__SEARCH_INDEX(cache_ptr, Addr, entry_ptr, fail_val)             \
@@ -1205,9 +1271,20 @@ if ( (cache_ptr)->index_size !=                                             \
  *		able to dirty, resize and/or move entries during the
  *		flush.
  *
+ *		JRM -- 12/13/14
+ *		Added code to set cache_ptr->slist_changed to TRUE 
+ *		when an entry is inserted in the slist.
+ *
  *-------------------------------------------------------------------------
  */
 
+#if H5C_DO_SLIST_SANITY_CHECKS
+#define ENTRY_IN_SLIST(cache_ptr, entry_ptr) \
+    H5C_entry_in_skip_list((cache_ptr), (entry_ptr))
+#else /* H5C_DO_SLIST_SANITY_CHECKS */
+#define ENTRY_IN_SLIST(cache_ptr, entry_ptr) FALSE
+#endif /* H5C_DO_SLIST_SANITY_CHECKS */
+
 #if H5C_DO_SANITY_CHECKS
 
 #define H5C__INSERT_ENTRY_IN_SLIST(cache_ptr, entry_ptr, fail_val)             \
@@ -1218,12 +1295,14 @@ if ( (cache_ptr)->index_size !=                                             \
     HDassert( (entry_ptr)->size > 0 );                                         \
     HDassert( H5F_addr_defined((entry_ptr)->addr) );                           \
     HDassert( !((entry_ptr)->in_slist) );                                      \
+    HDassert( !ENTRY_IN_SLIST((cache_ptr), (entry_ptr)) );                     \
                                                                                \
     if(H5SL_insert((cache_ptr)->slist_ptr, entry_ptr, &(entry_ptr)->addr) < 0) \
         HGOTO_ERROR(H5E_CACHE, H5E_BADVALUE, (fail_val),                       \
                     "Can't insert entry in skip list")                         \
                                                                                \
     (entry_ptr)->in_slist = TRUE;                                              \
+    (cache_ptr)->slist_changed = TRUE;                                         \
     (cache_ptr)->slist_len++;                                                  \
     (cache_ptr)->slist_size += (entry_ptr)->size;                              \
     (cache_ptr)->slist_len_increase++;                                         \
@@ -1244,12 +1323,14 @@ if ( (cache_ptr)->index_size !=                                             \
     HDassert( (entry_ptr)->size > 0 );                                         \
     HDassert( H5F_addr_defined((entry_ptr)->addr) );                           \
     HDassert( !((entry_ptr)->in_slist) );                                      \
+    HDassert( !ENTRY_IN_SLIST((cache_ptr), (entry_ptr)) );                     \
                                                                                \
     if(H5SL_insert((cache_ptr)->slist_ptr, entry_ptr, &(entry_ptr)->addr) < 0) \
         HGOTO_ERROR(H5E_CACHE, H5E_BADVALUE, (fail_val),                       \
                     "Can't insert entry in skip list")                         \
                                                                                \
     (entry_ptr)->in_slist = TRUE;                                              \
+    (cache_ptr)->slist_changed = TRUE;                                         \
     (cache_ptr)->slist_len++;                                                  \
     (cache_ptr)->slist_size += (entry_ptr)->size;                              \
                                                                                \
@@ -1290,6 +1371,10 @@ if ( (cache_ptr)->index_size !=                                             \
  *		Updated sanity checks for the new is_read_only and
  *		ro_ref_count fields in H5C_cache_entry_t.
  *
+ *		JRM -- 12/13/14
+ *		Added code to set cache_ptr->slist_changed to TRUE 
+ *		when an entry is removed from the slist.
+ *
  *-------------------------------------------------------------------------
  */
 
@@ -1311,6 +1396,7 @@ if ( (cache_ptr)->index_size !=                                             \
                     "Can't delete entry from skip list.")           \
                                                                     \
     HDassert( (cache_ptr)->slist_len > 0 );                         \
+    (cache_ptr)->slist_changed = TRUE;                              \
     (cache_ptr)->slist_len--;                                       \
     HDassert( (cache_ptr)->slist_size >= (entry_ptr)->size );       \
     (cache_ptr)->slist_size -= (entry_ptr)->size;                   \
@@ -1341,6 +1427,11 @@ if ( (cache_ptr)->index_size !=                                             \
  *		able to dirty, resize and/or move entries during the
  *		flush.
  *
+ *		JRM -- 12/13/14
+ *		Note that we do not set cache_ptr->slist_changed to TRUE 
+ *		in this case, as the structure of the slist is not
+ *		modified.
+ *
  *-------------------------------------------------------------------------
  */
 
@@ -2706,6 +2797,10 @@ if ( (cache_ptr)->index_size !=                                             \
  *		   the max_cache_size limit until the next time the cache
  *		   attempts to load or insert an entry.
  *
+ *		d) When the evictions_enabled field is false (see below),
+ *		   the cache size will increase without limit until the
+ *		   field is set to true.
+ *
  * min_clean_size: Nominal minimum number of clean bytes in the cache.
  *              The cache attempts to maintain this number of bytes of
  *              clean data so as to avoid case b) above.  Again, this is
@@ -2756,7 +2851,7 @@ if ( (cache_ptr)->index_size !=                                             \
  *              This value should not be mistaken for footprint of the
  *              cache in memory.  The average cache entry is small, and
  *              the cache has a considerable overhead.  Multiplying the
- *              index_size by two should yield a conservative estimate
+ *              index_size by three should yield a conservative estimate
  *              of the cache's memory footprint.
  *
  * clean_index_size: Number of bytes of clean entries currently stored in
@@ -2767,12 +2862,7 @@ if ( (cache_ptr)->index_size !=                                             \
  *
  *		WARNING:
  *
- *		1) The clean_index_size field is not maintained by the
- *		   index macros, as the hash table doesn't care whether
- *		   the entry is clean or dirty.  Instead the field is
- *		   maintained in the H5C__UPDATE_RP macros.
- *
- *		2) The value of the clean_index_size must not be mistaken
+ *		   The value of the clean_index_size must not be mistaken
  *		   for the current clean size of the cache.  Rather, the
  *		   clean size of the cache is the current value of
  *		   clean_index_size plus the amount of empty space (if any)
@@ -2784,13 +2874,6 @@ if ( (cache_ptr)->index_size !=                                             \
  *		Thus we should have the invariant that clean_index_size +
  *		dirty_index_size == index_size.
  *
- *		WARNING:
- *
- *		1) The dirty_index_size field is not maintained by the
- *		   index macros, as the hash table doesn't care whether
- *		   the entry is clean or dirty.  Instead the field is
- *		   maintained in the H5C__UPDATE_RP macros.
- *
  * index:	Array of pointer to H5C_cache_entry_t of size
  *		H5C__HASH_TABLE_LEN.  At present, this value is a power
  *		of two, not the usual prime number.
@@ -2806,6 +2889,37 @@ if ( (cache_ptr)->index_size !=                                             \
  *		changing the H5C__HASH_FCN macro and the deletion of the
  *		H5C__HASH_MASK #define.  No other changes should be required.
  *
+ * With the addition of the take ownership flag, it is possible that 
+ * an entry may be removed from the cache as the result of the flush of 
+ * a second entry.  In general, this causes little trouble, but it is 
+ * possible that the entry removed may be the next entry in the scan of 
+ * a list.  In this case, we must be able to detect the fact that the 
+ * entry has been removed, so that the scan doesn't attempt to proceed with
+ * an entry that is no longer in the cache.
+ *
+ * The following fields are maintained to facilitate this.
+ *
+ * entries_removed_counter:	Counter that is incremented each time an
+ *		entry is removed from the cache by any means (eviction, 
+ *		expungement, or take ownership at this point in time).
+ *		Functions that perform scans on lists may set this field
+ *		to zero prior to calling H5C_flush_single_entry().  
+ *		Unexpected changes to the counter indicate that an entry 
+ *		was removed from the cache as a side effect of the flush.
+ *
+ * last_entry_removed_ptr:	Pointer to the instance of H5C_cache_entry_t
+ *		which contained the last entry to be removed from the cache,
+ *		or NULL if there either is no such entry, or if a function
+ *		performing a scan of a list has set this field to NULL prior
+ *		to calling H5C_flush_single_entry().
+ *
+ *		WARNING!!! This field must NEVER be dereferenced.  It is 
+ *		maintained to allow functions that perform scans of lists
+ *		to compare this pointer with their pointers to next, thus
+ *		allowing them to avoid unnecessary restarts of scans if the
+ *		pointers don't match, and if entries_removed_counter is 
+ *		one.
+ *
  *
  * With the addition of cache entry tagging, it is possible that 
  * an entry may be inserted into the cache without a tag during testing
@@ -2825,6 +2939,21 @@ if ( (cache_ptr)->index_size !=                                             \
  * are flushed. (this has been changed -- dirty entries are now removed from
  * the skip list as they are flushed.  JRM - 10/25/05)
  *
+ * slist_changed: Boolean flag used to indicate whether the contents of 
+ *		the slist has changed since the last time this flag was
+ *		reset.  This is used in the cache flush code to detect 
+ *		conditions in which pre-serialize or serialize callbacks
+ *		have modified the slist -- which obliges us to restart 
+ *		the scan of the slist from the beginning.
+ *
+ * slist_change_in_pre_serialize: Boolean flag used to indicate that 
+ *		a pre_serialize call has modified the slist since the 
+ *		last time this flag was reset.
+ *
+ * slist_change_in_serialize: Boolean flag used to indicate that 
+ *		a serialize call has modified the slist since the 
+ *		last time this flag was reset.
+ *
  * slist_len:   Number of entries currently in the skip list
  *              used to maintain a sorted list of dirty entries in the
  *              cache.
@@ -2855,6 +2984,11 @@ if ( (cache_ptr)->index_size !=                                             \
  *              explicit tests for that case should be added when said
  *              HDasserts are removed.
  *
+ *		Update: There are now two possible last entries
+ *		(superblock and file driver info message).  This
+ *		number will probably increase as we add superblock
+ *		messages.   JRM -- 11/18/14
+ *
  * With the addition of the fractal heap, the cache must now deal with
  * the case in which entries may be dirtied, moved, or have their sizes
  * changed during a flush.  To allow sanity checks in this situation, the
@@ -2863,10 +2997,11 @@ if ( (cache_ptr)->index_size !=                                             \
  *
  * slist_len_increase: Number of entries that have been added to the
  * 		slist since the last time this field was set to zero.
+ *		Note that this value can be negative.
  *
  * slist_size_increase: Total size of all entries that have been added
  * 		to the slist since the last time this field was set to
- * 		zero.
+ * 		zero.  Note that this value can be negative.
  *
  *
  * When a cache entry is protected, it must be removed from the LRU
@@ -2905,9 +3040,9 @@ if ( (cache_ptr)->index_size !=                                             \
  *         replacement policy code).
  *
  *      2) A pinned entry can be accessed or modified at any time.
- *         Therefore, the cache must check with the entry owner
- *         before flushing it.  If permission is denied, the
- *         cache just skips the entry in the flush.
+ *         This places an additional burden on the associated pre-serialize
+ *	   and serialize callbacks, which must ensure the the entry is in 
+ *	   a consistant state before creating an image of it.
  *
  *      3) A pinned entry can be marked as dirty (and possibly
  *         change size) while it is unprotected.
@@ -2965,7 +3100,8 @@ if ( (cache_ptr)->index_size !=                                             \
  * be collective and the other processes will not know to participate.
  *
  * To deal with this issue, I have modified the usual LRU policy by adding
- * clean and dirty LRU lists to the usual LRU list.
+ * clean and dirty LRU lists to the usual LRU list.  In general, these 
+ * lists are only exist in parallel builds.
  *
  * The clean LRU list is simply the regular LRU list with all dirty cache
  * entries removed.
@@ -2982,7 +3118,7 @@ if ( (cache_ptr)->index_size !=                                             \
  *
  * Even if we start with a completely clean cache, a sequence of protects
  * without unprotects can empty the clean LRU list.  In this case, the
- * cache must grow temporarily.  At the next write, we will attempt to
+ * cache must grow temporarily.  At the next sync point, we will attempt to
  * evict enough entries to reduce index_size to less than max_cache_size.
  * While this will usually be possible, all bets are off if enough entries
  * are protected.
@@ -2992,14 +3128,14 @@ if ( (cache_ptr)->index_size !=                                             \
  *
  * LRU_list_len:  Number of cache entries currently on the LRU list.
  *
- *              Observe that LRU_list_len + pl_len must always equal
- *              index_len.
+ *              Observe that LRU_list_len + pl_len + pel_len must always 
+ *		equal index_len.
  *
  * LRU_list_size:  Number of bytes of cache entries currently residing on the
  *              LRU list.
  *
- *              Observe that LRU_list_size + pl_size must always equal
- *              index_size.
+ *              Observe that LRU_list_size + pl_size + pel_size must always 
+ *		equal index_size.
  *
  * LRU_head_ptr:  Pointer to the head of the doubly linked LRU list.  Cache
  *              entries on this list are linked by their next and prev fields.
@@ -3244,6 +3380,11 @@ if ( (cache_ptr)->index_size !=                                             \
  *		equal to the array index has been evicted from the cache in
  *		the current epoch.
  *
+ * take_ownerships: Array of int64 of length H5C__MAX_NUM_TYPE_IDS + 1.  The 
+ *		cells are used to record the number of times an entry with 
+ *		type id equal to the array index has been removed from the 
+ *		cache via the H5C__TAKE_OWNERSHIP_FLAG in the current epoch.
+ *
  * moves:       Array of int64 of length H5C__MAX_NUM_TYPE_IDS + 1.  The cells
  *		are used to record the number of times an entry with type
  *		id equal to the array index has been moved in the current
@@ -3252,7 +3393,7 @@ if ( (cache_ptr)->index_size !=                                             \
  * entry_flush_moves: Array of int64 of length H5C__MAX_NUM_TYPE_IDS + 1. 
  * 		The cells are used to record the number of times an entry
  * 		with type id equal to the array index has been moved
- * 		during its flush callback in the current epoch.
+ * 		during its pre-serialize callback in the current epoch.
  *
  * cache_flush_moves: Array of int64 of length H5C__MAX_NUM_TYPE_IDS + 1. 
  * 		The cells are used to record the number of times an entry
@@ -3297,7 +3438,8 @@ if ( (cache_ptr)->index_size !=                                             \
  * entry_flush_size_changes:  Array of int64 of length
  * 		H5C__MAX_NUM_TYPE_IDS + 1.  The cells are used to record
  * 		the number of times an entry with type id equal to the
- * 		array index has changed size while in its flush callback.
+ * 		array index has changed size while in its pre-serialize 
+ *		callback.
  *
  * cache_flush_size_changes:  Array of int64 of length
  * 		H5C__MAX_NUM_TYPE_IDS + 1.  The cells are used to record
@@ -3370,7 +3512,33 @@ if ( (cache_ptr)->index_size !=                                             \
  *
  * entries_scanned_to_make_space: Number of entries scanned only when looking
  *              for entries to evict in order to make space in cache.
-
+ *
+ * 
+ * As entries are now capable of moving, loading, dirtying, and deleting 
+ * other entries in their pre_serialize and serialize callbacks, it has 
+ * been necessary to insert code to restart scans of lists so as to avoid 
+ * improper behavior if the next entry in the list is the target of one on 
+ * these operations.
+ *
+ * The following fields are use to count such occurances.  They are used 
+ * both in tests (to verify that the scan has been restarted), and to 
+ * obtain estimates of how frequently these restarts occur.
+ *
+ * slist_scan_restarts: Number of times a scan of the slist (that contains
+ *		calls to H5C_flush_single_entry()) has been restarted to 
+ *		avoid potential issues with change of status of the next 
+ *		entry in the scan.
+ *
+ * LRU_scan_restarts: Number of times a scan of the LRU list (that contains
+ *              calls to H5C_flush_single_entry()) has been restarted to 
+ *              avoid potential issues with change of status of the next 
+ *              entry in the scan.
+ *
+ * hash_bucket_scan_restarts: Number of times a scan of a hash bucket list
+ *		(that contains calls to H5C_flush_single_entry()) has been 
+ *		restarted to avoid potential issues with change of status 
+ *		of the next entry in the scan.
+ *
  * The remaining stats are collected only when both H5C_COLLECT_CACHE_STATS
  * and H5C_COLLECT_CACHE_ENTRY_STATS are true.
  *
@@ -3438,9 +3606,17 @@ struct H5C_t {
     size_t			dirty_index_size;
     H5C_cache_entry_t *		(index[H5C__HASH_TABLE_LEN]);
 
+    /* Fields to detect entries removed during scans */
+    int64_t			entries_removed_counter;
+    H5C_cache_entry_t *		last_entry_removed_ptr;
+
     /* Field to disable tag validation */
     hbool_t                     ignore_tags;
 
+    /* Fields for maintaining list of in-order entries, for flushing */
+    hbool_t			slist_changed;
+    hbool_t			slist_change_in_pre_serialize;
+    hbool_t			slist_change_in_serialize;
     int32_t                     slist_len;
     size_t                      slist_size;
     H5SL_t *                    slist_ptr;
@@ -3515,6 +3691,7 @@ struct H5C_t {
     int64_t                     clears[H5C__MAX_NUM_TYPE_IDS + 1];
     int64_t                     flushes[H5C__MAX_NUM_TYPE_IDS + 1];
     int64_t                     evictions[H5C__MAX_NUM_TYPE_IDS + 1];
+    int64_t                     take_ownerships[H5C__MAX_NUM_TYPE_IDS + 1];
     int64_t                     moves[H5C__MAX_NUM_TYPE_IDS + 1];
     int64_t                     entry_flush_moves[H5C__MAX_NUM_TYPE_IDS + 1];
     int64_t                     cache_flush_moves[H5C__MAX_NUM_TYPE_IDS + 1];
@@ -3559,6 +3736,11 @@ struct H5C_t {
     int32_t                     max_entries_skipped_in_msic;
     int32_t                     max_entries_scanned_in_msic;
     int64_t                     entries_scanned_to_make_space;
+ 
+    /* Fields for tracking skip list scan restarts */
+    int64_t			slist_scan_restarts;
+    int64_t			LRU_scan_restarts;
+    int64_t			hash_bucket_scan_restarts;
 
 #if H5C_COLLECT_CACHE_ENTRY_STATS
     int32_t                     max_accesses[H5C__MAX_NUM_TYPE_IDS + 1];
@@ -3585,7 +3767,8 @@ struct H5C_t {
 /******************************/
 /* Package Private Prototypes */
 /******************************/
-
+H5_DLL herr_t H5C__flush_single_entry(const H5F_t *f, hid_t dxpl_id,
+    H5C_cache_entry_t *entry_ptr, unsigned flags, int64_t *entry_size_change_ptr);
 
 #endif /* _H5Cpkg_H */
 
diff --git a/src/H5Cprivate.h b/src/H5Cprivate.h
index 3413381..3cd74c1 100644
--- a/src/H5Cprivate.h
+++ b/src/H5Cprivate.h
@@ -40,9 +40,9 @@
 /* Library Private Macros */
 /**************************/
 
-#define H5C_DO_SANITY_CHECKS		0
-#define H5C_DO_TAGGING_SANITY_CHECKS	1
-#define H5C_DO_EXTREME_SANITY_CHECKS	0
+/* Cache configuration settings */
+#define H5C__MAX_NUM_TYPE_IDS	28
+#define H5C__PREFIX_LEN		32
 
 /* This sanity checking constant was picked out of the air.  Increase
  * or decrease it if appropriate.  Its purposes is to detect corrupt
@@ -52,23 +52,6 @@
  */
 #define H5C_MAX_ENTRY_SIZE		((size_t)(32 * 1024 * 1024))
 
-/* H5C_COLLECT_CACHE_STATS controls overall collection of statistics
- * on cache activity.  In general, this #define should be set to 0.
- */
-#define H5C_COLLECT_CACHE_STATS	0
-
-/* H5C_COLLECT_CACHE_ENTRY_STATS controls collection of statistics
- * in individual cache entries.
- *
- * H5C_COLLECT_CACHE_ENTRY_STATS should only be defined to true if
- * H5C_COLLECT_CACHE_STATS is also defined to true.
- */
-#if H5C_COLLECT_CACHE_STATS
-#define H5C_COLLECT_CACHE_ENTRY_STATS	1
-#else
-#define H5C_COLLECT_CACHE_ENTRY_STATS	0
-#endif /* H5C_COLLECT_CACHE_STATS */
-
 #ifdef H5_HAVE_PARALLEL
 /* we must maintain the clean and dirty LRU lists when we are compiled
  * with parallel support.
@@ -82,10 +65,20 @@
 #define H5C_MAINTAIN_CLEAN_AND_DIRTY_LRU_LISTS  0
 #endif /* H5_HAVE_PARALLEL */
 
-/* Flags returned from the 'flush' callback */
-#define H5C_CALLBACK__NO_FLAGS_SET		0x0
-#define H5C_CALLBACK__SIZE_CHANGED_FLAG		0x1
-#define H5C_CALLBACK__MOVED_FLAG		0x2
+/* Flags for cache client class behavior */
+#define H5C__CLASS_NO_FLAGS_SET			((unsigned)0x0)
+#define H5C__CLASS_SPECULATIVE_LOAD_FLAG	((unsigned)0x1)
+#define H5C__CLASS_COMPRESSED_FLAG		((unsigned)0x2)
+/* The following flags may only appear in test code */
+#define H5C__CLASS_NO_IO_FLAG			((unsigned)0x4)
+#define H5C__CLASS_SKIP_READS			((unsigned)0x8)
+#define H5C__CLASS_SKIP_WRITES			((unsigned)0x10)
+
+/* Flags for pre-serialize callback */
+#define H5C__SERIALIZE_NO_FLAGS_SET	((unsigned)0)
+#define H5C__SERIALIZE_RESIZED_FLAG	((unsigned)0x1)
+#define H5C__SERIALIZE_MOVED_FLAG	((unsigned)0x2)
+#define H5C__SERIALIZE_COMPRESSED_FLAG  ((unsigned)0x4)
 
 /* Upper and lower limits on cache size.  These limits are picked
  * out of a hat -- you should be able to change them as necessary.
@@ -112,11 +105,9 @@
  */
 #define H5C__NUM_FLUSH_DEP_HEIGHTS            6
 
-#ifndef NDEBUG
 /* Values for cache entry magic field */
 #define H5C__H5C_CACHE_ENTRY_T_MAGIC		0x005CAC0A
 #define H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC	0xDeadBeef
-#endif /* NDEBUG */
 
 /* Cache configuration validation definitions */
 #define H5C_RESIZE_CFG__VALIDATE_GENERAL        0x1
@@ -169,9 +160,13 @@
  * These flags apply to H5C_insert_entry():
  * 	H5C__SET_FLUSH_MARKER_FLAG
  * 	H5C__PIN_ENTRY_FLAG
+ *	H5C__FLUSH_LAST_FLAG		; super block only
+ *	H5C__FLUSH_COLLECTIVELY_FLAG	; super block only
  *
  * These flags apply to H5C_protect()
  * 	H5C__READ_ONLY_FLAG
+ *	H5C__FLUSH_LAST_FLAG		; super block only 
+ *	H5C__FLUSH_COLLECTIVELY_FLAG	; super block only
  *
  * These flags apply to H5C_unprotect():
  * 	H5C__SET_FLUSH_MARKER_FLAG
@@ -197,6 +192,7 @@
  * 	H5C__FLUSH_CLEAR_ONLY_FLAG
  * 	H5C__FLUSH_MARKED_ENTRIES_FLAG
  *      H5C__TAKE_OWNERSHIP_FLAG
+ *      H5C__DEL_FROM_SLIST_ON_DESTROY_FLAG
  */
 #define H5C__NO_FLAGS_SET			0x0000
 #define H5C__SET_FLUSH_MARKER_FLAG		0x0001
@@ -213,6 +209,56 @@
 #define H5C__TAKE_OWNERSHIP_FLAG		0x1000
 #define H5C__FLUSH_LAST_FLAG			0x2000
 #define H5C__FLUSH_COLLECTIVELY_FLAG		0x4000
+#define H5C__DEL_FROM_SLIST_ON_DESTROY_FLAG     0x8000
+
+/* Debugging/sanity checking/statistics settings */
+#ifndef NDEBUG
+#define H5C_DO_SANITY_CHECKS		1
+#define H5C_DO_SLIST_SANITY_CHECKS	0
+#define H5C_DO_TAGGING_SANITY_CHECKS	1
+#define H5C_DO_EXTREME_SANITY_CHECKS	0
+#else /* NDEBUG */
+/* With rare execptions, the following defines should be set 
+ * to 0 if NDEBUG is defined 
+ */
+#define H5C_DO_SANITY_CHECKS		0
+#define H5C_DO_SLIST_SANITY_CHECKS	0
+#define H5C_DO_TAGGING_SANITY_CHECKS	0
+#define H5C_DO_EXTREME_SANITY_CHECKS	0
+#endif /* NDEBUG */
+
+/* Note: The memory sanity checks aren't going to work until I/O filters are
+ *      changed to call a particular alloc/free routine for their buffers,
+ *      because the H5AC__SERIALIZE_RESIZED_FLAG set by the fractal heap
+ *      direct block serialize callback calls H5Z_pipeline().  When the I/O
+ *      filters are changed, then we should implement "cache image alloc/free"
+ *      routines that the fractal heap direct block (and global heap) serialize
+ *      calls can use when resizing (and re-allocating) their image in the
+ *      cache. -QAK */
+#define H5C_DO_MEMORY_SANITY_CHECKS	0
+
+/* H5C_COLLECT_CACHE_STATS controls overall collection of statistics
+ * on cache activity.  In general, this #define should be set to 1 in
+ * debug mode, and 0 in production mode..
+ */
+
+#ifndef NDEBUG
+#define H5C_COLLECT_CACHE_STATS	1
+#else /* NDEBUG */
+#define H5C_COLLECT_CACHE_STATS	0
+#endif /* NDEBUG */
+
+/* H5C_COLLECT_CACHE_ENTRY_STATS controls collection of statistics
+ * in individual cache entries.
+ *
+ * H5C_COLLECT_CACHE_ENTRY_STATS should only be defined to true if
+ * H5C_COLLECT_CACHE_STATS is also defined to true.
+ */
+#if H5C_COLLECT_CACHE_STATS
+#define H5C_COLLECT_CACHE_ENTRY_STATS	1
+#else
+#define H5C_COLLECT_CACHE_ENTRY_STATS	0
+#endif /* H5C_COLLECT_CACHE_STATS */
 
 
 /****************************/
@@ -223,63 +269,842 @@
 typedef struct H5C_t H5C_t;
 
 
-/*
- * Class methods pertaining to caching.	 Each type of cached object will
- * have a constant variable with permanent life-span that describes how
- * to cache the object.	 That variable will be of type H5C_class_t and
- * have the following required fields...
+/***************************************************************************
+ *
+ * Struct H5C_class_t
+ *
+ * Instances of H5C_class_t are used to specify the callback functions
+ * used by the metadata cache for each class of metadata cache entry.
+ * The fields of the structure are discussed below:
+ *
+ * id:	Integer field containing the unique ID of the class of metadata
+ * 	cache entries.
+ *
+ * name: Pointer to a string containing the name of the class of metadata
+ * 	cache entries.
+ *
+ * mem_type:  Instance of H5FD_mem_t, that is used to supply the
+ * 	mem type passed into H5F_block_read().
+ *
+ * flags:  Flags indicating class-specific behavior.
+ *
+ *	Whoever created the flags field neglected to document the meanings 
+ *      of the flags he created.  Hence the following discussion of the 
+ *	H5C__CLASS_SPECULATIVE_LOAD_FLAG and (to a lesser extent) 
+ *	H5C__CLASS_COMPRESSED_FLAG should be viewed with suspicion, 
+ *	as the meanings are divined from the source code, and thus may be 
+ *	inaccurate.  Please correct any errors you find.
+ *
+ *	Possible flags are:
+ *
+ *	H5C__CLASS_NO_FLAGS_SET: No special processing.
+ *
+ *	H5C__CLASS_SPECULATIVE_LOAD_FLAG: This flag appears to be used
+ *		only in H5C_load_entry().  When it is set, entries are 
+ *		permitted to change their sizes on the first attempt 
+ *		to load.  
+ *
+ *		If the new size is larger than the old, the read buffer
+ *		is reallocated to the new size, loaded from file, and the 
+ *		deserialize routine is called a second time on the 
+ *		new buffer.  The entry returned by the first call to 
+ *		the deserialize routine is discarded (via the free_icr
+ *		call) after the new size is retrieved (via the image_len
+ *		call).  Note that the new size is used as the size of the 
+ *		entry in the cache.
+ *
+ *		If the new size is smaller than the old, no new loads 
+ *		or desearializes are performed, but the new size becomes
+ *		the size of the entry in the cache.
+ *
+ *		When this flag is set, an attempt to read past the 
+ *		end of file is pemitted.  In this case, if the size 
+ *		returned get_load_size callback would result in a 
+ *		read past the end of file, the size is trunkated to 
+ *		avoid this, and processing proceeds as normal.
  *
- * LOAD:	Loads an object from disk to memory.  The function
- *		should allocate some data structure and return it.
+ *	H5C__CLASS_COMPRESSED_FLAG: This flags indicates that the entry 
+ *		may be compressed -- i.e. its on disk image is run through 
+ *		filters on the way to and from disk.  Thus the uncompressed 
+ *		(or unfiltered) size of the entry may be different from the 
+ *		size of the entry in file.  
  *
- * FLUSH:	Writes some data structure back to disk.  It would be
- *		wise for the data structure to include dirty flags to
- *		indicate whether it really needs to be written.	 This
- *		function is also responsible for freeing memory allocated
- *		by the LOAD method if the DEST argument is non-zero (by
- *              calling the DEST method).
+ *		This has the following implications:
  *
- * DEST:	Just frees memory allocated by the LOAD method.
+ *		On load, uncompressed size and load size may be different.  
+ *		Presumably, load size will be smaller than uncompressed 
+ *		size, but there is no requirement for this in the code 
+ *		(but note that I have inserted an assertion to this effect, 
+ *		which has not been triggered to date).
  *
- * CLEAR:	Just marks object as non-dirty.
+ *		On insertion, compressed (AKA filtered, AKA on disk) size 
+ *		is unknown, as the entry has yet to be run through filters.
+ *		Compressed size is computed whenever the entry is 
+ *		written (or the image is updated -- not relevant until 
+ *		journaling is brought back).
  *
- * NOTIFY:	Notify client that an action on an entry has taken/will take
- *              place
+ *		On dirty (of a clean entry), compressed (AKA filtered, 
+ *		AKA on disk) size becomes unknown.  Thus, compressed size
+ *		must be computed by the pre-serialize callback before the 
+ *		entry may be written.  
  *
- * SIZE:	Report the size (on disk) of the specified cache object.
- *		Note that the space allocated on disk may not be contiguous.
- */
+ *		Once the compressed size becomes unknown, it remains so 
+ *		until the on disk image is constructed.  
+ *
+ *		Observe that the cache needs to know the size of the entry
+ *		for space allocation purposes.  Since the compressed size 
+ *		can change or become unknown, it uses the uncompressed
+ *		size which may change, but which should always be known.  
+ *		The compressed size is used only for journaling and disk I/O.
+ *
+ *		While there is no logical reason why they could not be 
+ *		combined, due to absence of need and for simplicity of code, 
+ *		the cache does not permit both the the 
+ *		H5C__CLASS_COMPRESSED_FLAG and the 
+ *		H5C__CLASS_SPECULATIVE_LOAD_FLAG to be set in the same 
+ *		instance of H5C_class_t.
+ *
+ *      The following flags may only appear in test code.
+ *
+ *	H5C__CLASS_NO_IO_FLAG:  This flag is intended only for use in test 
+ *		code.  When it is set, any attempt to load an entry of 
+ *		the type with this flag set will trigger an assertion 
+ *		failure, and any flush of an entry with this flag set 
+ *		will not result in any write to file.
+ *
+ *	H5C__CLASS_SKIP_READS: This flags is intended only for use in test
+ *		code.  When it is set, reads on load will be skipped,
+ *		and an uninitialize buffer will be passed to the 
+ *		deserialize function.
+ *
+ *	H5C__CLASS_SKIP_WRITES: This flags is intended only for use in test
+ *		code.  When it is set, writes of buffers prepared by the 
+ *		serialize callback will be skipped.
+ *
+ * GET_LOAD_SIZE: Pointer to the 'get load size' function.
+ *
+ * 	This function must be able to determine the size of the disk image of
+ *      a metadata cache entry, given the 'udata' that will be passed to the
+ *      'deserialize' callback.
+ *
+ *	Note that if either the H5C__CLASS_SPECULATIVE_LOAD_FLAG or
+ *	the H5C__CLASS_COMPRESSED_FLAG is set, the disk image size 
+ *	returned by this callback is either a first guess (if the 
+ *	H5C__CLASS_SPECULATIVE_LOAD_FLAG is set) or (if the
+ *      H5C__CLASS_COMPRESSED_FLAG is set), the exact on disk size 
+ *	of the entry whether it has been run through filters or not.
+ *	In all other cases, the value returned should be the correct 
+ *	uncompressed size of the entry.
+ *
+ *	The typedef for the deserialize callback is as follows:
+ *
+ * 	   typedef herr_t (*H5C_get_load_size_func_t)(void *udata_ptr,
+ * 	                                           size_t *image_len_ptr);
+ *
+ *	The parameters of the deserialize callback are as follows:
+ *
+ *	udata_ptr: Pointer to user data provided in the protect call, which
+ *         	will also be passed through to the deserialize callback.
+ *
+ *	image_len_ptr: Pointer to the location in which the length in bytes 
+ *		of the in file image to be deserialized is to be returned.
+ *
+ *              This value is used by the cache to determine the size of
+ *              the disk image for the metadata, in order to read the disk
+ *              image from the file.
+ *
+ *	Processing in the get_load_size function should proceed as follows:
+ *
+ *	If successful, the function will place the length of the on disk
+ *	image associated with supplied user data in *image_len_ptr, and 
+ *	then return SUCCEED.
+ *
+ *	On failure, the function must return FAIL and push error information
+ *	onto the error stack with the error API routines, without modifying
+ *      the value pointed to by the image_len_ptr.
+ *
+ *
+ * DESERIALIZE: Pointer to the deserialize function.
+ *
+ * 	This function must be able to read a buffer containing the on disk 
+ *	image of a metadata cache entry, allocate and load the equivalent 
+ *	in core representation, and return a pointer to that representation.
+ *
+ *	The typedef for the deserialize callback is as follows:
+ *
+ * 	   typedef void *(*H5C_deserialize_func_t)(const void * image_ptr,
+ * 	                                           size_t len,
+ *                                                 void * udata_ptr,
+ *                                                 boolean * dirty_ptr);
+ *
+ *	The parameters of the deserialize callback are as follows:
+ *
+ *	image_ptr: Pointer to a buffer of length len containing the
+ *		contents of the file starting at addr and continuing
+ *		for len bytes.
+ *
+ *	len:    Length in bytes of the in file image to be deserialized.
+ *
+ *              This parameter is supplied mainly for sanity checking.
+ *              Sanity checks should be performed when compiled in debug
+ *              mode, but the parameter may be unused when compiled in
+ *              production mode.
+ *
+ *	udata_ptr: Pointer to user data provided in the protect call, which
+ *         	must be passed through to the deserialize callback.
+ *
+ *      dirty_ptr:  Pointer to boolean which the deserialize function
+ *      	must use to mark the entry dirty if it has to modify
+ *      	the entry to clean up file corruption left over from
+ *      	an old bug in the HDF5 library.
+ *
+ *	Processing in the deserialize function should proceed as follows:
+ *
+ *      If the image contains valid data, and is of the correct length,
+ *      the deserialize function must allocate space for an in core
+ *      representation of that data, load the contents of the image into
+ *      the space allocated for the in core representation, and return
+ *      a pointer to the in core representation.  Observe that an
+ *      instance of H5C_cache_entry_t must be the first item in this
+ *      representation.  The cache will initialize it after the callback
+ *      returns.
+ *
+ *      Note that the structure of the in core representation is otherwise
+ *      up to the cache client.  All that is required is that the pointer
+ *      returned be sufficient for the clients purposes when it is returned
+ *      on a protect call.
+ *
+ *      If the deserialize function has to clean up file corruption
+ *      left over from an old bug in the HDF5 library, it must set
+ *      *dirty_ptr to TRUE.  If it doesn't, no action is needed as
+ *      *dirty_ptr will be set to FALSE before the deserialize call.
+ *
+ *      If the operation fails for any reason (i.e. bad data in buffer, bad
+ *      buffer length, malloc failure, etc.) the function must return NULL and
+ *      push error information on the error stack with the error API routines.
+ *
+ *	Exceptions to the above:
+ *
+ *	If the H5C__CLASS_SPECULATIVE_LOAD_FLAG is set, the buffer supplied
+ *	to the function need not be currect on the first invocation of the 
+ *	callback in any single attempt to load the entry.
+ *
+ *	In this case, if the buffer is larger than necessary, the function
+ *	should load the entry as described above and not flag an error due
+ *	to the oversized buffer.  The cache will correct its mis-apprehension
+ *	of the entry size with a subsequent call to the image_len callback.
+ *
+ *	If the buffer is too small, and this is the first deserialize call
+ *	in the entry load operation, the function should not flag an error.
+ *	Instead, it must compute the correct size of the entry, allocate an
+ *	in core representation and initialize it to the extent that an 
+ *	immediate call to the image len callback will return the correct 
+ *	image size.
+ *
+ *	In this case, when the deserialize callback returns, the cache will
+ *	call the image length callback, realize that the supplied buffer was
+ *	too small, discard the returned in core representation, allocate
+ *	and load a new buffer of the correct size from file, and then call
+ *	the deserialize callback again.
+ *
+ *	If the H5C__CLASS_COMPRESSED_FLAG is set, exceptions are as per the
+ *	H5C__CLASS_SPECULATIVE_LOAD_FLAG, save that only oversized buffers
+ *	are permitted.
+ *
+ *
+ * IMAGE_LEN: Pointer to the image length callback.
+ *
+ *	This callback exists primarily to support 
+ *	H5C__CLASS_SPECULATIVE_LOAD_FLAG and H5C__CLASS_COMPRESSED_FLAG 
+ *	discussed above, although it is also used to obtain the size of 
+ *	newly inserted entries.
+ *
+ *	In the case of the H5C__CLASS_SPECULATIVE_LOAD_FLAG, it is used to
+ *	allow the client to change the size of an entry in the deserialize
+ *	callback.
+ *
+ *	For the H5C__CLASS_COMPRESSED_FLAG, it is used to allow the client
+ *	to indicate whether the entry is compressed (i.e. whether entries
+ *	are run through filters) and if so, to report both the uncompressed 
+ *	and the compressed entry size (i.e. the actual on disk size after
+ *	the entry has been run through filters) if that value is known.
+ *
+ *	The callback is also used in H5C_insert_entry() to obtain the 
+ *	size of the newly inserted entry.
+ *
+ *      The typedef for the image_len callback is as follows:
+ *
+ *      typedef herr_t (*H5C_image_len_func_t)(void *thing,
+ *                                           size_t *image_len_ptr,
+ *                                           hbool_t *compressed_ptr,
+ *                                           size_t *compressed_image_len_ptr);
+ *
+ * 	The parameters of the image_len callback are as follows:
+ *
+ *	thing:  Pointer to the in core representation of the entry.
+ *
+ *	image_len_ptr: Pointer to size_t in which the callback will return
+ *		the length (in bytes) of the cache entry.
+ *
+ *		If the H5C__CLASS_COMPRESSED_FLAG is not set in the 
+ *		associated instance of H5C_class_t, or if the flag is 
+ *		set, and the callback sets *compressed_ptr to FALSE,
+ *		this size is the actual size of the entry on disk.
+ *
+ *		Otherwise, this size is the uncompressed size of the 
+ *		entry -- which the cache will use for all purposes OTHER
+ *		than journal writes and disk I/O.
+ *
+ *	compressed_ptr: Pointer to a boolean flag indicating whether 
+ *		the cache entry will be compressed / uncompressed on 
+ *		disk writes / reads.
+ *
+ *		If the H5C__CLASS_COMPRESSED_FLAG is not set in the
+ *              associated instance of H5C_class_t, *compressed_ptr 
+ *		must be set to FALSE.
+ *
+ *		If the H5C__CLASS_COMPRESSED_FLAG is set in the
+ *              associated instance of H5C_class_t, and filters are 
+ *		not enabled, *compressed_ptr must be set to FALSE.
+ *
+ *		If the H5C__CLASS_COMPRESSED_FLAG is set in the
+ *              associated instance of H5C_class_t, and filters are
+ *		enabled, the callback must set *compressed_ptr to TRUE.
+ *
+ *		Note that *compressed_ptr will always be set to FALSE 
+ *		by the caller prior to invocation of the callback.  Thus 
+ *		callbacks for clients that don't set the 
+ *		H5C__CLASS_COMPRESSED_FLAG can ignore this parameter.
+ *
+ *	compressed_image_len_ptr: Pointer to size_t in which the callback 
+ *		may return the length (in bytes) of the compressed on 
+ *		disk image of the entry, or the uncompressed size if the
+ *		compressed size has not yet been calculated.
+ *
+ *		Since computing the compressed image len is expensive, 
+ *		the callback should only report the most recently computed
+ *		value -- which will typically be incorrect if the entry
+ *		is dirty.
+ *
+ *		If *compressed_ptr is set to FALSE, *compressed_image_len_ptr
+ *		should be set to zero.  However, as *compressed_image_len_ptr
+ *		will be initialize to zero prior to the call, the callback 
+ *		need not modify it if the H5C__CLASS_COMPRESSED_FLAG is 
+ *		not set.
+ *
+ *	If the H5C__CLASS_COMPRESSED_FLAG is not set in the associated 
+ *	instance of H5C_class_t, processing in the image_len function 
+ *	should proceed as follows:
+ *
+ *	If successful, the function will place the length of the on disk
+ *	image associated with the in core representation provided in the
+ *	thing parameter in *image_len_ptr, and then return SUCCEED.  Since
+ *	*compressed_ptr and *compressed_image_len_ptr will be initialized to 
+ *	FALSE and zero respectively before the call, the callback need not
+ *	modify these values, and may declare the associated parameters as 
+ *	UNUSED.
+ *
+ *	If the H5C__CLASS_COMPRESSED_FLAG is set in the associated 
+ *      instance of H5C_class_t, processing in the image_len function 
+ *      should proceed as follows:
+ *
+ *	If successful, the function will place the uncompressed length of 
+ *	the on disk image associated with the in core representation 
+ *	provided in the thing parameter in *image_len_ptr.  If filters 
+ *	are not enabled for the entry, it will set *compressed_ptr to FALSE,
+ *      and *compressed_image_len_ptr to zero.  If filters are enabled, 
+ *	it will set *compressed_ptr to TRUE.  In this case, it must set 
+ *	*compressed_image_len_ptr equal to the last computed compressed
+ *	if the compressed size, or to the uncompressed size if that value
+ *	is yet to be computed.  In all cases, it will return SUCCEED if 
+ *	successful.
+ *
+ *	In either case, if the function fails, it must return FAIL and 
+ *	push error information onto the error stack with the error API 
+ *	routines, and return without modifying the values pointed to by 
+ *	the image_len_ptr, compressed_ptr, and compressed_image_len_ptr
+ *	parameters.
+ *
+ * PRE_SERIALIZE: Pointer to the pre-serialize callback.
+ *
+ *	The pre-serialize callback is invoked by the metadata cache before
+ *	it needs a current on-disk image of the metadata entry for purposes
+ *	either constructing a journal or flushing the entry to disk.
+ *
+ *      If the client needs to change the address or compressed or 
+ *	uncompressed length of the entry prior to flush, the pre-serialize 
+ *	callback is responsible for these actions, so that the actual 
+ *	serialize callback (described below) is only responsible for 
+ *	serializing the data structure, not moving it on disk or resizing it.
+ *
+ *	In addition, the client may use the pre-serialize callback to 
+ *	ensure that the entry is ready to be flushed -- in particular, 
+ *	if the entry contains references to other entries that are in 
+ *	temporary file space, the pre-serialize callback must move those
+ *	entries into real file space so that the serialzed entry will 
+ *	contain no invalid data.
+ *
+ *	One would think that the base address and length of
+ *	the length of the entry's image on disk would be well known. 
+ *	However, that need not be the case as free space section info
+ *	entries will change size (and possibly location) depending on the 
+ *	number of blocks of free space being manages, and fractal heap 
+ *	direct blocks can change compressed size (and  possibly location) 
+ *	on serialization if compression is enabled.  Similarly, it may
+ *	be necessary to move entries from temporary to real file space.
+ *
+ *	The pre-serialize callback must report any such changes to the 
+ *	cache, which must then update its internal structures as needed.
+ *
+ *	The typedef for the pre-serialize callback is as follows:
+ *
+ *	typedef herr_t (*H5C_pre_serialize_func_t)(const H5F_t *f,
+ *                                             hid_t dxpl_id,
+ *                                             void * thing,
+ *                                             haddr_t addr,
+ *                                             size_t len,
+ *					       size_t compressed_len,
+ *                                             haddr_t * new_addr_ptr,
+ *                                             size_t * new_len_ptr,
+ *					       size_t * new_compressed_len_ptr,
+ *                                             unsigned * flags_ptr);
+ *
+ *	The parameters of the pre-serialize callback are as follows:
+ *
+ *	f:	File pointer -- needed if other metadata cache entries
+ *		must be modified in the process of serializing the
+ *		target entry.
+ *
+ *	dxpl_id: dxpl_id passed with the file pointer to the cache, and
+ *	        passed on to the callback.  Necessary as some callbacks
+ *	        revise the size and location of the target entry, or
+ *	        possibly other entries on pre-serialize.
+ *
+ *	thing:  Pointer to void containing the address of the in core
+ *		representation of the target metadata cache entry. 
+ *		This is the same pointer returned by a protect of the
+ *		addr and len given above.
+ *
+ *	addr:   Base address in file of the entry to be serialized.
+ *
+ *		This parameter is supplied mainly for sanity checking.
+ *		Sanity checks should be performed when compiled in debug
+ *		mode, but the parameter may be unused when compiled in
+ *		production mode.
+ *
+ *	len:    Length in bytes of the in file image of the entry to be
+ *		serialized.  Also the size the image passed to the 
+ *		serialize callback (discussed below) unless either that 
+ *		value is altered by this function, or the entry will be
+ *		compressed.  In the latter case, the compressed size
+ *		of the entry will be reported in *new_compressed_len_ptr.
+ *
+ *		This parameter is supplied mainly for sanity checking.
+ *		Sanity checks should be performed when compiled in debug
+ *		mode, but the parameter may be unused when compiled in
+ *		production mode.
+ *
+ *	compressed_len: If the entry is to be compressed (i.e. run through 
+ *		filters) prior to flush, Length in bytes of the last know 
+ *		compressed size of the entry -- or the uncompressed size 
+ *		if no such value exists (i.e. the entry has been inserted, 
+ *		but never flushed).  This parameter should be set to zero
+ *		in all other cases.
+ *
+ *		This parameter is supplied mainly for sanity checking.
+ *		Sanity checks should be performed when compiled in debug
+ *		mode, but the parameter may be unused when compiled in
+ *		production mode.
+ *
+ *	new_addr_ptr:  Pointer to haddr_t.  If the entry is moved by
+ *		the serialize function, the new on disk base address must
+ *		be stored in *new_addr_ptr, and the appropriate flag set
+ *		in *flags_ptr.  
+ *
+ *		If the entry is not moved by the serialize function, 
+ *		*new_addr_ptr is undefined on pre-serialize callback 
+ *		return.
+ *
+ *	new_len_ptr:  Pointer to size_t.  If the entry is resized by the
+ *		serialize function, the new length of the on disk image
+ *		must be stored in *new_len_ptr, and the appropriate flag set
+ *              in *flags_ptr.
+ *
+ *		If the entry is not resized by the pre-serialize function, 
+ *		*new_len_ptr is undefined on pre-serialize callback 
+ *		return.
+ *
+ *	new_compressed_len_ptr: Pointer to size_t.  If the image will be
+ *		compressed (i.e. run through filters) prior to being 
+ *		written to disk, the compressed size (in bytes) of the
+ *		on disk image must be stored in *new_compressed_len_ptr,
+ *		and the appropriate flag set in *flags_ptr.  
+ *
+ *	flags_ptr:  Pointer to an unsigned integer used to return flags
+ *		indicating whether the preserialize function resized or moved
+ *		the entry, or computed its compressed size.  If the entry was 
+ *		neither resized or moved, nor will be compressed,
+ *		the serialize function must set *flags_ptr to zero. 
+ *		H5C__SERIALIZE_RESIZED_FLAG, H5C__SERIALIZE_MOVED_FLAG
+ *		and H5C__SERIALIZE_COMPRESSED_FLAG must be set to indicate 
+ *		a resize, a move, or compression respectively.
+ *
+ *	        If the H5C__SERIALIZE_RESIZED_FLAG is set, the new length
+ *	        must be stored in *new_len_ptr.
+ *
+ *	        If the H5C__SERIALIZE_MOVED_FLAG flag is set, the
+ *	        new image base address must be stored in *new_addr_ptr. 
+ *
+ *		If the H5C__SERIALIZE_COMPRESSED_FLAG is set, the 
+ *		compressed size of the new image must be stored in 
+ *		*new_compressed_len_ptr. 
+ *
+ *	Processing in the pre-serialize function should proceed as follows:
+ *
+ *	The pre-serialize function must examine the in core representation
+ *	indicated by the thing parameter, if the pre-serialize function does
+ *      not need to change the size or location of the on-disk image, or
+ *	compute its compress size, it must set *flags_ptr to zero. 
+ *
+ *	If the (uncompressed) size of the on-disk image must be changed, 
+ *	the pre-serialize function must load the length of the new image 
+ *	into *new_len_ptr, and set the H5C__SERIALIZE_RESIZED_FLAG in 
+ *	*flags_ptr. 
+ *
+ *	If the base address of the on disk image must be changed, the
+ *      pre-serialize function must set *new_addr_ptr to the new base address,
+ *      and set the H5C__SERIALIZE_MOVED_FLAG in *flags_ptr.
+ *
+ *	If the H5C__CLASS_COMPRESSED_FLAG is set in the assocated instance
+ *	of H5C_class_t, and filters (i.e. compression) are enabled, the 
+ *	pre-serialize function must compute the compressed size of the 
+ *	on disk image, and if it has changed, load this value into 
+ *	*new_compressed_len_ptr, and set H5C__SERIALIZE_COMPRESSED_FLAG in 
+ *	*flags_ptr.
+ *
+ *	Note that to do this, the preserialize function will typically have 
+ *	to serialize the entry, and run it through the filters to obtain 
+ *	the compressed size.  For efficiency, the compressed image may
+ *	be stored to be copied into the supplied buffer by the 
+ *	serialize callback.  Needless to say this is awkward.  We may
+ *	want to re-work the API for cache clients to simplify this.
+ *
+ *	In addition, the pre-serialize callback may perform any other 
+ *	processing required before the entry is written to disk
+ *
+ *	If it is successful, the function must return SUCCEED. 
+ *
+ *	If it fails for any reason, the function must return FAIL and
+ *	push error information on the error stack with the error API
+ *	routines.
+ *
+ *
+ * SERIALIZE: Pointer to the serialize callback.
+ *
+ *	The serialize callback is invoked by the metadata cache whenever
+ *	it needs a current on disk image of the metadata entry for purposes
+ *	either constructing a journal entry or flushing the entry to disk.
+ *
+ *	At this point, the base address and length of the entry's image on
+ *      disk must be well known and not change during the serialization
+ *      process. 
+ *
+ *	While any size and/or location changes must have been handled 
+ *	by a pre-serialize call, the client may elect to handle any other 
+ *	changes to the entry required to place it in correct form for 
+ *	writing to disk in this call.
+ *
+ *	The typedef for the serialize callback is as follows:
+ *
+ *	typedef herr_t (*H5C_serialize_func_t)(const H5F_t *f,
+ *                                             void * image_ptr,
+ *                                             size_t len,
+ *                                             void * thing);
+ *
+ *	The parameters of the serialize callback are as follows:
+ *
+ *	f:	File pointer -- needed if other metadata cache entries
+ *		must be modified in the process of serializing the
+ *		target entry.
+ *
+ *	image_ptr: Pointer to a buffer of length len bytes into which a
+ *		serialized image of the target metadata cache entry is
+ *		to be written.
+ *
+ * 		Note that this buffer will not in general be initialized
+ * 		to any particular value.  Thus the serialize function may
+ * 		not assume any initial value and must set each byte in
+ * 		the buffer.
+ *
+ *	len:    Length in bytes of the in file image of the entry to be
+ *		serialized.  Also the size of *image_ptr (below).  If 
+ *		compression is not enabled, this value is simply the 
+ *		uncompressed size of the entry's image on disk.  If 
+ *		compression is enabled, this value is the size of the 
+ *		compressed image.
+ *
+ *		This parameter is supplied mainly for sanity checking.
+ *		Sanity checks should be performed when compiled in debug
+ *		mode, but the parameter may be unused when compiled in
+ *		production mode.
+ *
+ *	thing:  Pointer to void containing the address of the in core
+ *		representation of the target metadata cache entry. 
+ *		This is the same pointer returned by a protect of the
+ *		addr and len given above.
+ *
+ *	Processing in the serialize function should proceed as follows:
+ *
+ *	If there are any remaining changes to the entry required before 
+ *	write to disk, they must be dealt with first.
+ *
+ *	The serialize function must then examine the in core 
+ *	representation indicated by the thing parameter, and write a 
+ *	serialized (and possibly compressed) image of its contents into 
+ *	the provided buffer. 
+ *
+ *	If it is successful, the function must return SUCCEED. 
+ *
+ *	If it fails for any reason, the function must return FAIL and
+ *	push error information on the error stack with the error API
+ *	routines.
+ *
+ *
+ * NOTIFY: Pointer to the notify callback.
+ *
+ *      The notify callback is invoked by the metadata cache when a cache
+ *      action on an entry has taken/will take place and the client indicates
+ *      it wishes to be notified about the action.
+ *
+ *	The typedef for the notify callback is as follows:
+ *
+ *	typedef herr_t (*H5C_notify_func_t)(H5C_notify_action_t action,
+ *                                          void *thing);
+ *
+ * 	The parameters of the notify callback are as follows:
+ *
+ *	action: An enum indicating the metadata cache action that has taken/
+ *              will take place.
+ *
+ *	thing:  Pointer to void containing the address of the in core
+ *		representation of the target metadata cache entry.  This
+ *		is the same pointer that would be returned by a protect
+ *		of the addr and len of the entry. 
+ *
+ *	Processing in the notify function should proceed as follows:
+ *
+ *	The notify function may perform any action it would like, including
+ *      metadata cache calls.
+ *
+ *	If the function is successful, it must return SUCCEED. 
+ *
+ *	If it fails for any reason, the function must return FAIL and
+ *	push error information on the error stack with the error API
+ *	routines. 
+ *
+ *
+ * FREE_ICR: Pointer to the free ICR callback.
+ *
+ *	The free ICR callback is invoked by the metadata cache when it
+ *	wishes to evict an entry, and needs the client to free the memory
+ *	allocated for the in core representation. 
+ *
+ *	The typedef for the free ICR callback is as follows:
+ *
+ *	typedef herr_t (*H5C_free_icr_func_t)(void * thing));
+ *
+ * 	The parameters of the free ICR callback are as follows:
+ *
+ *	thing:  Pointer to void containing the address of the in core
+ *		representation of the target metadata cache entry.  This
+ *		is the same pointer that would be returned by a protect
+ *		of the addr and len of the entry. 
+ *
+ *	Processing in the free ICR function should proceed as follows:
+ *
+ *	The free ICR function must free all memory allocated to the
+ *	in core representation. 
+ *
+ *	If the function is successful, it must return SUCCEED. 
+ *
+ *	If it fails for any reason, the function must return FAIL and
+ *	push error information on the error stack with the error API
+ *	routines. 
+ *
+ *	At least when compiled with debug, it would be useful if the
+ *	free ICR call would fail if the in core representation has been
+ *	modified since the last serialize of clear callback.
+ *
+ * CLEAR: Pointer to the clear callback.
+ *
+ *	In principle, there should be no need for the clear callback,
+ *	as the dirty flag should be maintained by the metadata cache.
+ *.  
+ *	However, some clients maintain dirty bits on internal data, 
+ *	and we need some way of keeping these dirty bits in sync with 
+ *	those maintained by the metadata cache.  This callback exists
+ *	to serve this purpose.  If defined, it is called whenever the 
+ *	cache marks dirty entry clean, or when the cache is about to 
+ *	discard a dirty entry without writing it to disk (This 
+ *	happens as the result of an unprotect call with the 
+ *	H5AC__DELETED_FLAG set, and the H5C__TAKE_OWNERSHIP_FLAG not
+ *	set.)
+ *
+ *	Arguably, this functionality should be in the NOTIFY callback.
+ *	However, this callback is specific to only a few clients, and 
+ *	it will be called relatively frequently.  Hence it is made its
+ *	own callback to minimize overhead.
+ *
+ *	The typedef for the clear callback is as follows:
+ *
+ *	typedef herr_t (*H5C_clear_func_t)(const H5F_t *f,
+ *                                         void * thing, 
+ *                                         hbool_t about_to_destroy);
+ *
+ *	The parameters of the clear callback are as follows:
+ *
+ *	f:	File pointer.
+ *
+ *	thing:  Pointer to void containing the address of the in core
+ *		representation of the target metadata cache entry.  This
+ *		is the same pointer that would be returned by a protect()
+ *		call of the associated addr and len.
+ *
+ *	about_to_destroy: Boolean flag used to indicate whether the 
+ *		metadata cache is about to destroy the target metadata
+ *		cache entry.  The callback may use this flag to omit
+ *		operations that are irrelevant it the entry is about 
+ *		to be destroyed.
+ *
+ *	Processing in the clear function should proceed as follows:
+ *
+ *	Reset all internal dirty bits in the target metadata cache entry.
+ *
+ *	If the about_to_destroy flag is TRUE, the clear function may 
+ *	ommit any dirty bit that will not trigger a sanity check failure 
+ *	or otherwise cause problems in the subsequent free icr call.
+ *	In particular, the call must ensure that the free icr call will
+ *	not fail due to changes prior to this call, and after the 
+ *	last serialize or clear call.
+ *
+ *	If the function is successful, it must return SUCCEED. 
+ *
+ *	If it fails for any reason, the function must return FAIL and
+ *	push error information on the error stack with the error API
+ *	routines. 
+ *
+ * GET_FSF_SIZE: Pointer to the get file space free size callback.
+ *
+ *	In principle, there is no need for the get file space free size
+ *	callback.  However, as an optimization, it is sometimes convenient
+ *	to allocate and free file space for a number of cache entries 
+ *	simultaneously in a single contiguous block of file space.
+ *
+ *	File space allocation is done by the client, so the metadata cache
+ *	need not be involved.  However, since the metadata cache typically
+ *      handles file space release when an entry is destroyed, some 
+ *	adjustment on the part of the metadata cache is required for this
+ *	operation.
+ *
+ *      The get file space free size callback exists to support this 
+ *	operation.
+ *
+ *	If a group of cache entries that were allocated as a group are to 
+ *	be discarded and their file space released, the type of the first
+ *	(i.e. lowest address) entry in the group must implement the 
+ *	get free file space size callback.  
+ *
+ *	To free the file space of all entries in the group in a single 
+ *	operation, first expunge all entries other than the first without 
+ *	the free file space flag.  
+ *
+ *	Then, to complete the operation, unprotect or expunge the first
+ *	entry in the block with the free file space flag set.  Since 
+ *	the get free file space callback is implemented, the metadata 
+ *	cache will use this callback to get the size of the block to be
+ *	freed, instead of using the size of the entry as is done otherwise.
+ *
+ *	At present this callback is used only by the H5FA and H5EA dblock
+ *	and dblock page client classes.
+ *
+ *      The typedef for the clear callback is as follows:
+ *
+ *      typedef herr_t (*H5C_get_fsf_size_t)(const void * thing,
+ *                                                size_t *fsf_size_ptr);
+ *
+ *      The parameters of the clear callback are as follows:
+ *
+ *      thing:  Pointer to void containing the address of the in core
+ *              representation of the target metadata cache entry.  This
+ *              is the same pointer that would be returned by a protect()
+ *              call of the associated addr and len.
+ *
+ *	fs_size_ptr: Pointer to size_t in which the callback will return
+ *              the size of the piece of file space to be freed.  Note 
+ *		that the space to be freed is presumed to have the same 
+ *		base address as the cache entry.
+ *
+ *      The function simply returns the size of the block of file space
+ *	to be freed in *fsf_size_ptr.  
+ *
+ *	If the function is successful, it must return SUCCEED.
+ *
+ *      If it fails for any reason, the function must return FAIL and
+ *      push error information on the error stack with the error API
+ *      routines.
+ *
+ ***************************************************************************/
 
 /* Actions that can be reported to 'notify' client callback */
 typedef enum H5C_notify_action_t {
-    H5C_NOTIFY_ACTION_AFTER_INSERT,     /* Entry has been added to the cache */
-                                        /* (could be loaded from file with
-                                         *      'protect' call, or inserted
-                                         *      with 'set' call)
+    H5C_NOTIFY_ACTION_AFTER_INSERT,     /* Entry has been added to the cache 
+                                         * via the insert call
+                                         */
+    H5C_NOTIFY_ACTION_AFTER_LOAD,	/* Entry has been loaded into the 
+                                         * from file via the protect call
+                                         */
+    H5C_NOTIFY_ACTION_AFTER_FLUSH,	/* Entry has just been flushed to
+ 					 * file.
+                                         */
+    H5C_NOTIFY_ACTION_BEFORE_EVICT      /* Entry is about to be evicted 
+                                         * from cache.
                                          */
-    H5C_NOTIFY_ACTION_BEFORE_EVICT      /* Entry is about to be evicted from cache */
 } H5C_notify_action_t;
 
 /* Cache client callback function pointers */
-typedef void *(*H5C_load_func_t)(H5F_t *f, hid_t dxpl_id, haddr_t addr,
-    void *udata);
-typedef herr_t (*H5C_flush_func_t)(H5F_t *f, hid_t dxpl_id, hbool_t dest,
-    haddr_t addr, void *thing, unsigned *flags_ptr);
-typedef herr_t (*H5C_dest_func_t)(H5F_t *f, void *thing);
-typedef herr_t (*H5C_clear_func_t)(H5F_t *f, void *thing, hbool_t dest);
+typedef herr_t (*H5C_get_load_size_func_t)(const void *udata_ptr,
+    size_t *image_len_ptr);
+typedef void *(*H5C_deserialize_func_t)(const void *image_ptr,
+    size_t len, void *udata_ptr, hbool_t *dirty_ptr);
+typedef herr_t (*H5C_image_len_func_t)(const void *thing,
+    size_t *image_len_ptr, hbool_t *compressed_ptr, size_t *compressed_image_len_ptr);
+typedef herr_t (*H5C_pre_serialize_func_t)(const H5F_t *f, hid_t dxpl_id,
+    void *thing, haddr_t addr, size_t len, size_t compressed_len,
+    haddr_t *new_addr_ptr, size_t *new_len_ptr, size_t *new_compressed_len_ptr,
+    unsigned *flags_ptr);
+typedef herr_t (*H5C_serialize_func_t)(const H5F_t *f, void *image_ptr,
+    size_t len, void *thing);
 typedef herr_t (*H5C_notify_func_t)(H5C_notify_action_t action, void *thing);
-typedef herr_t (*H5C_size_func_t)(const H5F_t *f, const void *thing,
-    size_t *size_ptr);
+typedef herr_t (*H5C_free_icr_func_t)(void *thing);
+typedef herr_t (*H5C_clear_func_t)(const H5F_t *f, void * thing, 
+    hbool_t about_to_destroy);
+typedef herr_t (*H5C_get_fsf_size_t)(const void * thing, size_t *fsf_size_ptr);
 
 /* Metadata cache client class definition */
 typedef struct H5C_class_t {
-    int			id;
-    H5C_load_func_t	load;
-    H5C_flush_func_t	flush;
-    H5C_dest_func_t	dest;
-    H5C_clear_func_t	clear;
-    H5C_notify_func_t	notify;
-    H5C_size_func_t	size;
+    int				id;
+    const char *		name;
+    H5FD_mem_t			mem_type;
+    unsigned			flags;
+    H5C_get_load_size_func_t 	get_load_size;
+    H5C_deserialize_func_t 	deserialize;
+    H5C_image_len_func_t	image_len;
+    H5C_pre_serialize_func_t	pre_serialize;
+    H5C_serialize_func_t	serialize;
+    H5C_notify_func_t		notify;
+    H5C_free_icr_func_t	        free_icr;
+    H5C_clear_func_t		clear;
+    H5C_get_fsf_size_t		fsf_size;
 } H5C_class_t;
 
 /* Type defintions of callback functions used by the cache as a whole */
@@ -312,7 +1137,7 @@ typedef herr_t (*H5C_log_flush_func_t)(H5C_t *cache_ptr, haddr_t addr,
  *              just before the entry is freed.
  *
  *              This is necessary, as the LRU list can be changed out
- *              from under H5C_make_space_in_cache() by the flush
+ *              from under H5C_make_space_in_cache() by the serialize
  *              callback which may change the size of an existing entry,
  *              and/or load a new entry while serializing the target entry.
  *
@@ -325,18 +1150,66 @@ typedef herr_t (*H5C_log_flush_func_t)(H5C_t *cache_ptr, haddr_t addr,
  *              detect this case, and re-start its scan from the bottom
  *              of the LRU when this situation occurs.
  *
- *              This field is only compiled in debug mode.
+ * cache_ptr:	Pointer to the cache that this entry is contained within.
  *
  * addr:	Base address of the cache entry on disk.
  *
- * size:	Length of the cache entry on disk.  Note that unlike normal
- *		caches, the entries in this cache are of variable length.
- *		The entries should never overlap, and when we do writebacks,
- *		we will want to writeback adjacent entries where possible.
+ * size:	Length of the cache entry on disk in bytes(exception: if 
+ *		the entry is compressed on disk, this field contains the 
+ *		uncompressed size of the entry -- see discussion of 
+ *		compressed entries below).  Note that unlike normal 
+ *		caches, the entries in this cache are of arbitrary size.
+ *
+ *		With the exception of compressed entries, the file space
+ *		allocations for cache entries implied by the addr and size
+ *		fields must be disjoint.  For compressed entries,
+ *		the size field contains the uncompressed size -- thus in
+ *		in this case, substitution of compressed size for size 
+ *		must result in disjoint file space allocations.  However, 
+ *		as discussed below, the compressed size may not be know.
+ *
+ *		Any entry whose associated instance of H5C_class_t has the
+ *		H5C__CLASS_COMPRESSED_FLAG set may be compressed.  When
+ *		an entry is compressed (that is, when filters are enabled
+ *		on it), the compressed flag (see below) must be set, and 
+ *		the compressed size (if known), must be stored in 
+ *		the compressed_size field.
+ *
+ *		Since the compressed size will be unknown unless the 
+ *		entry is clean, or has an up to date image (see the 
+ *		image_ptr and image_up_to_date fields below), we use the 
+ *		uncompressed size for all purposes other than disk I/O.  
+ *		
+ * compressed:	Boolean flag that is set iff the instance of H5C_class_t
+ *		associated with the entry has the H5C__CLASS_COMPRESSED_FLAG
+ *		set, and filters are enabled on the entry.
+ *
+ * compressed_size: If compressed is TRUE, this field contains the actual
+ *		compressed size of the entry in bytes, which is also its 
+ *		true size on disk -- or the uncompressed size if the 
+ *		compressed size is unknown (i.e. the entry has been 
+ *		inserted in the cache, but it has not been compressed yet).
+ *              Note that this value will usually be incorrect if the 
+ *		entry is dirty.
+ *
+ *		Since this value is frequently out of date and expensive to 
+ *		compute, it is used only for disk I/O.  The uncompressed 
+ *		size of the entry (stored in the size field above) is used 
+ *		for all other purposes (i.e. computing the sum of the sizes 
+ *		of all entries in the cache, etc.).
  *
- *		NB: At present, entries need not be contiguous on disk.  Until
- *		    we fix this, we can't do much with writing back adjacent
- *		    entries.
+ *		If compressed is FALSE, this field should contain 0.
+ *
+ * image_ptr:	Pointer to void.  When not NULL, this field points to a
+ * 		dynamically allocated block of size bytes in which the
+ * 		on disk image of the metadata cache entry is stored.
+ *
+ * 		If the entry is dirty, the pre-serialize and serialize 
+ *		callbacks must be used to update this image before it is 
+ *		written to disk
+ *
+ * image_up_to_date:  Boolean flag that is set to TRUE when *image_ptr
+ * 		is up to date, and set to false when the entry is dirtied.
  *
  * type:	Pointer to the instance of H5C_class_t containing pointers
  *		to the methods for cache entries of the current type.  This
@@ -366,6 +1239,9 @@ typedef herr_t (*H5C_log_flush_func_t)(H5C_t *cache_ptr, haddr_t addr,
  *		      modules using the cache.  These still clear the
  *		      is_dirty field as before.  -- JRM 7/5/05
  *
+ *		Update: Management of the is_dirty field is now entirely
+ *		      in the cache.		 -- JRM 7/5/07
+ *
  * dirtied:	Boolean flag used to indicate that the entry has been
  * 		dirtied while protected.
  *
@@ -422,9 +1298,10 @@ typedef herr_t (*H5C_log_flush_func_t)(H5C_t *cache_ptr, haddr_t addr,
  * 		   policy code (LRU at present).
  *
  * 		2) A pinned entry can be accessed or modified at any time.
- * 		   Therefore, the cache must check with the entry owner
- * 		   before flushing it.  If permission is denied, the
- * 		   cache does not flush the entry.
+ * 		   This places an extra burden on the pre-serialize and 
+ *		   serialize callbacks, which must ensure that a pinned 
+ *		   entry is consistant and ready to write to disk before 
+ *		   generating an image.
  *
  * 		3) A pinned entry can be marked as dirty (and possibly
  *		   change size) while it is unprotected.
@@ -466,6 +1343,11 @@ typedef herr_t (*H5C_log_flush_func_t)(H5C_t *cache_ptr, haddr_t addr,
  *              will need to be expanded and tested appropriately if that
  *              functionality is desired.
  *
+ *		Update: There are now two possible last entries
+ *                   	(superblock and file driver info message).  This
+ *                   	number will probably increase as we add superblock
+ *                   	messages.   JRM -- 11/18/14
+ *
  * clear_on_unprotect:  Boolean flag used only in PHDF5.  When H5C is used
  *		to implement the metadata cache In the parallel case, only
  *		the cache with mpi rank 0 is allowed to actually write to
@@ -493,11 +1375,6 @@ typedef herr_t (*H5C_log_flush_func_t)(H5C_t *cache_ptr, haddr_t addr,
  * destroy_in_progress:  Boolean flag that is set to true iff the entry
  * 		is in the process of being flushed and destroyed.
  *
- * free_file_space_on_destroy:  Boolean flag that is set to true iff the entry
- * 		is in the process of being flushed and destroyed and the file
- *              space used by the object should be freed by the cache client's
- *              'dest' callback routine.
- *
  *
  * Fields supporting the 'flush dependency' feature:
  *
@@ -581,63 +1458,43 @@ typedef herr_t (*H5C_log_flush_func_t)(H5C_t *cache_ptr, haddr_t addr,
  * The use of the replacement policy fields under the Modified LRU policy
  * is discussed below:
  *
- * next:	Next pointer in either the LRU or the protected list,
- *		depending on the current value of protected.  If there
- *		is no next entry on the list, this field should be set
- *		to NULL.
+ * next:	Next pointer in either the LRU, the protected list, or 
+ *		the pinned list depending on the current values of 
+ *		is_protected and is_pinned.  If there is no next entry 
+ *		on the list, this field should be set to NULL.
  *
- * prev:	Prev pointer in either the LRU or the protected list,
- *		depending on the current value of protected.  If there
- *		is no previous entry on the list, this field should be
- *		set to NULL.
+ * prev:	Prev pointer in either the LRU, the protected list,
+ *		or the pinned list depending on the current values of 
+ *		is_protected and is_pinned.  If there is no previous 
+ *		entry on the list, this field should be set to NULL.
  *
  * aux_next:	Next pointer on either the clean or dirty LRU lists.
- *		This entry should be NULL when protected is true.  When
- *		protected is false, and dirty is true, it should point
- *		to the next item on the dirty LRU list.  When protected
- *		is false, and dirty is false, it should point to the
- *		next item on the clean LRU list.  In either case, when
- *		there is no next item, it should be NULL.
+ *		This entry should be NULL when either is_protected or 
+ *		is_pinned is true.  
+ *
+ *		When is_protected and is_pinned are false, and is_dirty is 
+ *		true, it should point to the next item on the dirty LRU 
+ *		list.  
+ *
+ *		When is_protected and is_pinned are false, and is_dirty is 
+ *		false, it should point to the next item on the clean LRU 
+ *		list.  In either case, when there is no next item, it 
+ *		should be NULL.
  *
  * aux_prev:	Previous pointer on either the clean or dirty LRU lists.
- *		This entry should be NULL when protected is true.  When
- *		protected is false, and dirty is true, it should point
- *		to the previous item on the dirty LRU list.  When protected
- *		is false, and dirty is false, it should point to the
- *		previous item on the clean LRU list.  In either case, when
- *		there is no previous item, it should be NULL.
- *
- *
- * Fields supporting metadata journaling:
- *
- * last_trans:	unit64_t containing the ID of the last transaction in
- * 		which this entry was dirtied.  If journaling is disabled,
- * 		or if the entry has never been dirtied in a transaction,
- * 		this field should be set to zero.  Once we notice that
- * 		the specified transaction has made it to disk, we will
- * 		reset this field to zero as well.
- *
- * 		We must maintain this field, as to avoid messages from
- * 		the future, we must not flush a dirty entry to disk
- * 		until the last transaction in which it was dirtied
- * 		has made it to disk in the journal file.
- *
- * trans_next:  Next pointer in the entries modified in the current
- * 		transaction list.  This field should always be null
- * 		unless journaling is enabled, the entry is dirty,
- * 		and last_trans field contains the current transaction
- * 		number.  Even if all these conditions are fulfilled,
- * 		the field will still be NULL if this is the last
- * 		entry on the list.
- *
- * trans_prev:  Previous pointer in the entries modified in the current
- * 		transaction list.  This field should always be null
- * 		unless journaling is enabled, the entry is dirty,
- * 		and last_trans field contains the current transaction
- * 		number.  Even if all these conditions are fulfilled,
- * 		the field will still be NULL if this is the first
- * 		entry on the list.
+ *		This entry should be NULL when either is_protected or 
+ *		is_pinned is true.  
+ *
+ *		When is_protected and is_pinned are false, and is_dirty is 
+ *		true, it should point to the previous item on the dirty 
+ *		LRU list.  
+ *	
+ *		When is_protected and is_pinned are false, and is_dirty 
+ *		is false, it should point to the previous item on the 
+ *		clean LRU list.  
  *
+ *		In either case, when there is no previous item, it should 
+ *		be NULL.
  *
  * Cache entry stats collection fields:
  *
@@ -659,12 +1516,14 @@ typedef herr_t (*H5C_log_flush_func_t)(H5C_t *cache_ptr, haddr_t addr,
  *
  ****************************************************************************/
 typedef struct H5C_cache_entry_t {
-#ifndef NDEBUG
     uint32_t			magic;
-#endif /* NDEBUG */
     H5C_t                     * cache_ptr;
     haddr_t			addr;
     size_t			size;
+    hbool_t			compressed;
+    size_t			compressed_size;
+    void  		      *	image_ptr;
+    hbool_t			image_up_to_date;
     const H5C_class_t	      *	type;
     haddr_t		        tag;
     hbool_t			is_dirty;
@@ -683,7 +1542,6 @@ typedef struct H5C_cache_entry_t {
 #endif /* H5_HAVE_PARALLEL */
     hbool_t			flush_in_progress;
     hbool_t			destroy_in_progress;
-    hbool_t		        free_file_space_on_destroy;
 
     /* fields supporting the 'flush dependency' feature: */
     struct H5C_cache_entry_t  *	flush_dep_parent;
@@ -1012,12 +1870,11 @@ H5_DLL void H5C_def_auto_resize_rpt_fcn(H5C_t *cache_ptr, int32_t version,
     double hit_rate, enum H5C_resize_status status,
     size_t old_max_cache_size, size_t new_max_cache_size,
     size_t old_min_clean_size, size_t new_min_clean_size);
-H5_DLL herr_t H5C_dest(H5F_t *f, hid_t primary_dxpl_id, hid_t secondary_dxpl_id);
-H5_DLL herr_t H5C_expunge_entry(H5F_t *f, hid_t primary_dxpl_id, hid_t secondary_dxpl_id,
+H5_DLL herr_t H5C_dest(H5F_t *f, hid_t dxpl_id);
+H5_DLL herr_t H5C_expunge_entry(H5F_t *f, hid_t dxpl_id,
     const H5C_class_t *type, haddr_t addr, unsigned flags);
-H5_DLL herr_t H5C_flush_cache(H5F_t *f, hid_t primary_dxpl_id, hid_t secondary_dxpl_id,
-    unsigned flags);
-H5_DLL herr_t H5C_flush_to_min_clean(H5F_t *f, hid_t primary_dxpl_id, hid_t secondary_dxpl_id);
+H5_DLL herr_t H5C_flush_cache(H5F_t *f, hid_t dxpl_id, unsigned flags);
+H5_DLL herr_t H5C_flush_to_min_clean(H5F_t *f, hid_t dxpl_id);
 H5_DLL herr_t H5C_get_cache_auto_resize_config(const H5C_t *cache_ptr,
     H5C_auto_size_ctl_t *config_ptr);
 H5_DLL herr_t H5C_get_cache_size(H5C_t *cache_ptr, size_t *max_size_ptr,
@@ -1029,19 +1886,18 @@ H5_DLL herr_t H5C_get_entry_status(const H5F_t *f, haddr_t addr,
     hbool_t *is_protected_ptr, hbool_t *is_pinned_ptr,
     hbool_t *is_flush_dep_parent_ptr, hbool_t *is_flush_dep_child_ptr);
 H5_DLL herr_t H5C_get_evictions_enabled(const H5C_t *cache_ptr, hbool_t *evictions_enabled_ptr);
+H5_DLL void * H5C_get_aux_ptr(const H5C_t *cache_ptr);
 H5_DLL FILE *H5C_get_trace_file_ptr(const H5C_t *cache_ptr);
 H5_DLL FILE *H5C_get_trace_file_ptr_from_entry(const H5C_cache_entry_t *entry_ptr);
-H5_DLL herr_t H5C_insert_entry(H5F_t *f, hid_t primary_dxpl_id, hid_t secondary_dxpl_id,
-    const H5C_class_t *type, haddr_t addr, void *thing, unsigned int flags);
-H5_DLL herr_t H5C_mark_entries_as_clean(H5F_t *f, hid_t primary_dxpl_id,
-    hid_t secondary_dxpl_id, int32_t ce_array_len, haddr_t *ce_array_ptr);
+H5_DLL herr_t H5C_insert_entry(H5F_t *f, hid_t dxpl_id, const H5C_class_t *type,
+    haddr_t addr, void *thing, unsigned int flags);
 H5_DLL herr_t H5C_mark_entry_dirty(void *thing);
 H5_DLL herr_t H5C_move_entry(H5C_t *cache_ptr, const H5C_class_t *type,
     haddr_t old_addr, haddr_t new_addr);
 H5_DLL herr_t H5C_pin_protected_entry(void *thing);
 H5_DLL herr_t H5C_create_flush_dependency(void *parent_thing, void *child_thing);
-H5_DLL void * H5C_protect(H5F_t *f, hid_t primary_dxpl_id, hid_t secondary_dxpl_id,
-    const H5C_class_t *type, haddr_t addr, void *udata, unsigned flags);
+H5_DLL void * H5C_protect(H5F_t *f, hid_t dxpl_id, const H5C_class_t *type,
+    haddr_t addr, void *udata, unsigned flags);
 H5_DLL herr_t H5C_reset_cache_hit_rate_stats(H5C_t *cache_ptr);
 H5_DLL herr_t H5C_resize_entry(void *thing, size_t new_size);
 H5_DLL herr_t H5C_set_cache_auto_resize_config(H5C_t *cache_ptr,
@@ -1055,19 +1911,21 @@ H5_DLL void H5C_stats__reset(H5C_t *cache_ptr);
 H5_DLL herr_t H5C_dump_cache(H5C_t *cache_ptr, const char *cache_name);
 H5_DLL herr_t H5C_unpin_entry(void *thing);
 H5_DLL herr_t H5C_destroy_flush_dependency(void *parent_thing, void *child_thing);
-H5_DLL herr_t H5C_unprotect(H5F_t *f, hid_t primary_dxpl_id, hid_t secondary_dxpl_id,
-    const H5C_class_t *type, haddr_t addr, void *thing, unsigned int flags);
+H5_DLL herr_t H5C_unprotect(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *thing,
+    unsigned int flags);
 H5_DLL herr_t H5C_validate_resize_config(H5C_auto_size_ctl_t *config_ptr,
     unsigned int tests);
 H5_DLL herr_t H5C_ignore_tags(H5C_t *cache_ptr);
 H5_DLL void H5C_retag_copied_metadata(H5C_t *cache_ptr, haddr_t metadata_tag);
 
 #ifdef H5_HAVE_PARALLEL
-H5_DLL herr_t H5C_apply_candidate_list(H5F_t *f, hid_t primary_dxpl_id,
-    hid_t secondary_dxpl_id, H5C_t *cache_ptr, int num_candidates,
-    haddr_t *candidates_list_ptr, int mpi_rank, int mpi_size);
+H5_DLL herr_t H5C_apply_candidate_list(H5F_t *f, hid_t dxpl_id,
+    H5C_t *cache_ptr, int num_candidates, haddr_t *candidates_list_ptr,
+    int mpi_rank, int mpi_size);
 H5_DLL herr_t H5C_construct_candidate_list__clean_cache(H5C_t *cache_ptr);
 H5_DLL herr_t H5C_construct_candidate_list__min_clean(H5C_t *cache_ptr);
+H5_DLL herr_t H5C_mark_entries_as_clean(H5F_t *f, hid_t dxpl_id, int32_t ce_array_len,
+    haddr_t *ce_array_ptr);
 #endif /* H5_HAVE_PARALLEL */
 
 #ifndef NDEBUG	/* debugging functions */
diff --git a/src/H5Dlayout.c b/src/H5Dlayout.c
index d7d7b88..01898f2 100644
--- a/src/H5Dlayout.c
+++ b/src/H5Dlayout.c
@@ -253,7 +253,7 @@ H5D__layout_oh_create(H5F_t *file, hid_t dxpl_id, H5O_t *oh, H5D_t *dset,
             HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to create EFL file name heap")
 
         /* Pin the heap down in memory */
-        if(NULL == (heap = H5HL_protect(file, dxpl_id, efl->heap_addr, H5AC_WRITE)))
+        if(NULL == (heap = H5HL_protect(file, dxpl_id, efl->heap_addr, H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_DATASET, H5E_CANTPROTECT, FAIL, "unable to protect EFL file name heap")
 
         /* Insert "empty" name first */
diff --git a/src/H5EA.c b/src/H5EA.c
index 37682e7..d96f9c2 100644
--- a/src/H5EA.c
+++ b/src/H5EA.c
@@ -148,7 +148,7 @@ HDfprintf(stderr, "%s: Called\n", FUNC);
 	H5E_THROW(H5E_CANTALLOC, "memory allocation failed for extensible array info")
 
     /* Lock the array header into memory */
-    if(NULL == (hdr = H5EA__hdr_protect(f, dxpl_id, ea_addr, ctx_udata, H5AC_WRITE)))
+    if(NULL == (hdr = H5EA__hdr_protect(f, dxpl_id, ea_addr, ctx_udata, H5AC__NO_FLAGS_SET)))
 	H5E_THROW(H5E_CANTPROTECT, "unable to load extensible array header")
 
     /* Point extensible array wrapper at header and bump it's ref count */
@@ -209,7 +209,7 @@ H5EA_open(H5F_t *f, hid_t dxpl_id, haddr_t ea_addr, void *ctx_udata))
 #ifdef QAK
 HDfprintf(stderr, "%s: ea_addr = %a\n", FUNC, ea_addr);
 #endif /* QAK */
-    if(NULL == (hdr = H5EA__hdr_protect(f, dxpl_id, ea_addr, ctx_udata, H5AC_READ)))
+    if(NULL == (hdr = H5EA__hdr_protect(f, dxpl_id, ea_addr, ctx_udata, H5AC__READ_ONLY_FLAG)))
         H5E_THROW(H5E_CANTPROTECT, "unable to load extensible array header, address = %llu", (unsigned long long)ea_addr)
 
     /* Check for pending array deletion */
@@ -333,7 +333,7 @@ END_FUNC(PRIV)  /* end H5EA_get_addr() */
  */
 BEGIN_FUNC(STATIC, ERR,
 herr_t, SUCCEED, FAIL,
-H5EA__lookup_elmt(const H5EA_t *ea, hid_t dxpl_id, hsize_t idx, H5AC_protect_t thing_acc,
+H5EA__lookup_elmt(const H5EA_t *ea, hid_t dxpl_id, hsize_t idx, unsigned thing_acc,
     void **thing, uint8_t **thing_elmt_buf, hsize_t *thing_elmt_idx,
     H5EA__unprotect_func_t *thing_unprot_func))
 
@@ -362,6 +362,9 @@ HDfprintf(stderr, "%s: Index %Hu\n", FUNC, idx);
     HDassert(thing_elmt_buf);
     HDassert(thing_unprot_func);
 
+    /* only the H5AC__READ_ONLY_FLAG may be set in thing_acc */
+    HDassert((thing_acc & (unsigned)(~H5AC__READ_ONLY_FLAG)) == 0);
+
     /* Set the shared array header's file context for this operation */
     hdr->f = ea->f;
 
@@ -377,7 +380,7 @@ HDfprintf(stderr, "%s: Index %Hu\n", FUNC, idx);
 HDfprintf(stderr, "%s: Index block address not defined!\n", FUNC, idx);
 #endif /* QAK */
         /* Check if we are allowed to create the thing */
-        if(H5AC_WRITE == thing_acc) {
+        if(0 == (thing_acc & H5AC__READ_ONLY_FLAG)) { /* i.e. r/w access */
             /* Create the index block */
             hdr->idx_blk_addr = H5EA__iblock_create(hdr, dxpl_id, &stats_changed);
             if(!H5F_addr_defined(hdr->idx_blk_addr))
@@ -435,7 +438,7 @@ HDfprintf(stderr, "%s: dblk_idx = %u, iblock->ndblk_addrs = %Zu\n", FUNC, dblk_i
             /* Check if the data block has been allocated on disk yet */
             if(!H5F_addr_defined(iblock->dblk_addrs[dblk_idx])) {
                 /* Check if we are allowed to create the thing */
-                if(H5AC_WRITE == thing_acc) {
+                if(0 == (thing_acc & H5AC__READ_ONLY_FLAG)) { /* i.e. r/w access */
                     haddr_t dblk_addr;        /* Address of data block created */
                     hsize_t dblk_off;         /* Offset of data block in array */
 
@@ -475,7 +478,7 @@ HDfprintf(stderr, "%s: dblk_idx = %u, iblock->ndblk_addrs = %Zu\n", FUNC, dblk_i
             /* Check if the super block has been allocated on disk yet */
             if(!H5F_addr_defined(iblock->sblk_addrs[sblk_off])) {
                 /* Check if we are allowed to create the thing */
-                if(H5AC_WRITE == thing_acc) {
+                if(0 == (thing_acc & H5AC__READ_ONLY_FLAG)) { /* i.e. r/w access */
                     haddr_t sblk_addr;        /* Address of data block created */
 
                     /* Create super block */
@@ -508,7 +511,7 @@ HDfprintf(stderr, "%s: dblk_idx = %u, sblock->ndblks = %Zu\n", FUNC, dblk_idx, s
             /* Check if the data block has been allocated on disk yet */
             if(!H5F_addr_defined(sblock->dblk_addrs[dblk_idx])) {
                 /* Check if we are allowed to create the thing */
-                if(H5AC_WRITE == thing_acc) {
+                if(0 == (thing_acc & H5AC__READ_ONLY_FLAG)) { /* i.e. r/w access */
                     haddr_t dblk_addr;        /* Address of data block created */
                     hsize_t dblk_off;         /* Offset of data block in array */
 
@@ -568,7 +571,7 @@ HDfprintf(stderr, "%s: sblock->dblk_page_size = %Zu\n", FUNC, sblock->dblk_page_
                 /* Check if page has been initialized yet */
                 if(!H5VM_bit_get(sblock->page_init, page_init_idx)) {
                     /* Check if we are allowed to create the thing */
-                    if(H5AC_WRITE == thing_acc) {
+                    if(0 == (thing_acc & H5AC__READ_ONLY_FLAG)) { /* i.e. r/w access */
                         /* Create the data block page */
                         if(H5EA__dblk_page_create(hdr, dxpl_id, sblock, dblk_page_addr) < 0)
                             H5E_THROW(H5E_CANTCREATE, "unable to create data block page")
@@ -677,7 +680,7 @@ HDfprintf(stderr, "%s: Index %Hu\n", FUNC, idx);
     hdr->f = ea->f;
 
     /* Look up the array metadata containing the element we want to set */
-    if(H5EA__lookup_elmt(ea, dxpl_id, idx, H5AC_WRITE, &thing, &thing_elmt_buf, &thing_elmt_idx, &thing_unprot_func) < 0)
+    if(H5EA__lookup_elmt(ea, dxpl_id, idx, H5AC__NO_FLAGS_SET, &thing, &thing_elmt_buf, &thing_elmt_idx, &thing_unprot_func) < 0)
         H5E_THROW(H5E_CANTPROTECT, "unable to protect array metadata")
 
     /* Sanity check */
@@ -762,7 +765,7 @@ HDfprintf(stderr, "%s: Index block address is: %a\n", FUNC, hdr->idx_blk_addr);
         hdr->f = ea->f;
 
         /* Look up the array metadata containing the element we want to set */
-        if(H5EA__lookup_elmt(ea, dxpl_id, idx, H5AC_READ, &thing, &thing_elmt_buf, &thing_elmt_idx, &thing_unprot_func) < 0)
+        if(H5EA__lookup_elmt(ea, dxpl_id, idx, H5AC__READ_ONLY_FLAG, &thing, &thing_elmt_buf, &thing_elmt_idx, &thing_unprot_func) < 0)
             H5E_THROW(H5E_CANTPROTECT, "unable to protect array metadata")
 
         /* Check if the thing holding the element has been created yet */
@@ -905,7 +908,7 @@ HDfprintf(stderr, "%s: Index %Hu\n", FUNC, idx);
     HDassert(ea);
 
     /* Look up the array metadata containing the element we want to set */
-    if(H5EA__lookup_elmt(ea, dxpl_id, idx, H5AC_WRITE, &thing, &thing_elmt_buf, &thing_elmt_idx, &thing_unprot_func) < 0)
+    if(H5EA__lookup_elmt(ea, dxpl_id, idx, H5AC__NO_FLAGS_SET, &thing, &thing_elmt_buf, &thing_elmt_idx, &thing_unprot_func) < 0)
         H5E_THROW(H5E_CANTPROTECT, "unable to protect array metadata")
 
     /* Sanity check */
@@ -960,7 +963,7 @@ HDfprintf(stderr, "%s: Index %Hu\n", FUNC, idx);
     HDassert(ea);
 
     /* Look up the array metadata containing the element we want to set */
-    if(H5EA__lookup_elmt(ea, dxpl_id, idx, H5AC_READ, &thing, &thing_elmt_buf, &thing_elmt_idx, &thing_unprot_func) < 0)
+    if(H5EA__lookup_elmt(ea, dxpl_id, idx, H5AC__READ_ONLY_FLAG, &thing, &thing_elmt_buf, &thing_elmt_idx, &thing_unprot_func) < 0)
         H5E_THROW(H5E_CANTPROTECT, "unable to protect array metadata")
 
     /* Sanity check */
@@ -1048,7 +1051,7 @@ HDfprintf(stderr, "%s: Called\n", FUNC);
 
         /* Lock the array header into memory */
         /* (OK to pass in NULL for callback context, since we know the header must be in the cache) */
-        if(NULL == (hdr = H5EA__hdr_protect(ea->f, dxpl_id, ea_addr, NULL, H5AC_WRITE)))
+        if(NULL == (hdr = H5EA__hdr_protect(ea->f, dxpl_id, ea_addr, NULL, H5AC__NO_FLAGS_SET)))
             H5E_THROW(H5E_CANTLOAD, "unable to load extensible array header")
 
         /* Set the shared array header's file context for this operation */
@@ -1112,7 +1115,7 @@ H5EA_delete(H5F_t *f, hid_t dxpl_id, haddr_t ea_addr, void *ctx_udata))
 #ifdef QAK
 HDfprintf(stderr, "%s: ea_addr = %a\n", FUNC, ea_addr);
 #endif /* QAK */
-    if(NULL == (hdr = H5EA__hdr_protect(f, dxpl_id, ea_addr, ctx_udata, H5AC_WRITE)))
+    if(NULL == (hdr = H5EA__hdr_protect(f, dxpl_id, ea_addr, ctx_udata, H5AC__NO_FLAGS_SET)))
         H5E_THROW(H5E_CANTPROTECT, "unable to protect extensible array header, address = %llu", (unsigned long long)ea_addr)
 
     /* Check for files using shared array header */
diff --git a/src/H5EAcache.c b/src/H5EAcache.c
index 70686fb..8a05282 100644
--- a/src/H5EAcache.c
+++ b/src/H5EAcache.c
@@ -57,13 +57,6 @@
 #define H5EA_SBLOCK_VERSION     0               /* Super block */
 #define H5EA_DBLOCK_VERSION     0               /* Data block */
 
-/* Size of stack buffer for serialization buffers */
-#define H5EA_HDR_BUF_SIZE       512
-#define H5EA_IBLOCK_BUF_SIZE    512
-#define H5EA_SBLOCK_BUF_SIZE    512
-#define H5EA_DBLOCK_BUF_SIZE    512
-#define H5EA_DBLK_PAGE_BUF_SIZE 512
-
 
 /******************/
 /* Local Typedefs */
@@ -80,35 +73,59 @@
 /********************/
 
 /* Metadata cache (H5AC) callbacks */
-static H5EA_hdr_t *H5EA__cache_hdr_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata);
-static herr_t H5EA__cache_hdr_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5EA_hdr_t *hdr, unsigned * flags_ptr);
-static herr_t H5EA__cache_hdr_clear(H5F_t *f, H5EA_hdr_t *hdr, hbool_t destroy);
-static herr_t H5EA__cache_hdr_size(const H5F_t *f, const H5EA_hdr_t *hdr, size_t *size_ptr);
-static herr_t H5EA__cache_hdr_dest(H5F_t *f, H5EA_hdr_t *hdr);
-static H5EA_iblock_t *H5EA__cache_iblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata);
-static herr_t H5EA__cache_iblock_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5EA_iblock_t *iblock, unsigned * flags_ptr);
-static herr_t H5EA__cache_iblock_clear(H5F_t *f, H5EA_iblock_t *iblock, hbool_t destroy);
-static herr_t H5EA__cache_iblock_notify(H5AC_notify_action_t action, H5EA_iblock_t *iblock);
-static herr_t H5EA__cache_iblock_size(const H5F_t *f, const H5EA_iblock_t *iblock, size_t *size_ptr);
-static herr_t H5EA__cache_iblock_dest(H5F_t *f, H5EA_iblock_t *iblock);
-static H5EA_sblock_t *H5EA__cache_sblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata);
-static herr_t H5EA__cache_sblock_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5EA_sblock_t *sblock, unsigned * flags_ptr);
-static herr_t H5EA__cache_sblock_clear(H5F_t *f, H5EA_sblock_t *sblock, hbool_t destroy);
-static herr_t H5EA__cache_sblock_size(const H5F_t *f, const H5EA_sblock_t *sblock, size_t *size_ptr);
-static herr_t H5EA__cache_sblock_notify(H5AC_notify_action_t action, H5EA_sblock_t *sblock);
-static herr_t H5EA__cache_sblock_dest(H5F_t *f, H5EA_sblock_t *sblock);
-static H5EA_dblock_t *H5EA__cache_dblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata);
-static herr_t H5EA__cache_dblock_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5EA_dblock_t *dblock, unsigned * flags_ptr);
-static herr_t H5EA__cache_dblock_clear(H5F_t *f, H5EA_dblock_t *dblock, hbool_t destroy);
-static herr_t H5EA__cache_dblock_size(const H5F_t *f, const H5EA_dblock_t *dblock, size_t *size_ptr);
-static herr_t H5EA__cache_dblock_notify(H5AC_notify_action_t action, H5EA_dblock_t *dblock);
-static herr_t H5EA__cache_dblock_dest(H5F_t *f, H5EA_dblock_t *dblock);
-static H5EA_dblk_page_t *H5EA__cache_dblk_page_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata);
-static herr_t H5EA__cache_dblk_page_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5EA_dblk_page_t *dblk_page, unsigned * flags_ptr);
-static herr_t H5EA__cache_dblk_page_clear(H5F_t *f, H5EA_dblk_page_t *dblk_page, hbool_t destroy);
-static herr_t H5EA__cache_dblk_page_size(const H5F_t *f, const H5EA_dblk_page_t *dblk_page, size_t *size_ptr);
-static herr_t H5EA__cache_dblk_page_notify(H5AC_notify_action_t action, H5EA_dblk_page_t *dblk_page);
-static herr_t H5EA__cache_dblk_page_dest(H5F_t *f, H5EA_dblk_page_t *dblk_page);
+static herr_t H5EA__cache_hdr_get_load_size(const void *udata, size_t *image_len);
+static void *H5EA__cache_hdr_deserialize(const void *image, size_t len,
+    void *udata, hbool_t *dirty);
+static herr_t H5EA__cache_hdr_image_len(const void *thing, size_t *image_len,
+    hbool_t *compressed_ptr, size_t *compressed_image_len_ptr);
+static herr_t H5EA__cache_hdr_serialize(const H5F_t *f, void *image, size_t len,
+    void *thing);
+static herr_t H5EA__cache_hdr_free_icr(void *thing);
+
+static herr_t H5EA__cache_iblock_get_load_size(const void *udata, size_t *image_len);
+static void *H5EA__cache_iblock_deserialize(const void *image, size_t len,
+    void *udata, hbool_t *dirty);
+static herr_t H5EA__cache_iblock_image_len(const void *thing, 
+    size_t *image_len, hbool_t *compressed_ptr, 
+    size_t *compressed_image_len_ptr);
+static herr_t H5EA__cache_iblock_serialize(const H5F_t *f, void *image, size_t len,
+    void *thing);
+static herr_t H5EA__cache_iblock_notify(H5AC_notify_action_t action, void *thing);
+static herr_t H5EA__cache_iblock_free_icr(void *thing);
+
+static herr_t H5EA__cache_sblock_get_load_size(const void *udata, size_t *image_len);
+static void *H5EA__cache_sblock_deserialize(const void *image, size_t len,
+    void *udata, hbool_t *dirty);
+static herr_t H5EA__cache_sblock_image_len(const void *thing, 
+    size_t *image_len, hbool_t *compressed_ptr, 
+    size_t *compressed_image_len_ptr);
+static herr_t H5EA__cache_sblock_serialize(const H5F_t *f, void *image, size_t len,
+    void *thing);
+static herr_t H5EA__cache_sblock_notify(H5AC_notify_action_t action, void *thing);
+static herr_t H5EA__cache_sblock_free_icr(void *thing);
+
+static herr_t H5EA__cache_dblock_get_load_size(const void *udata, size_t *image_len);
+static void *H5EA__cache_dblock_deserialize(const void *image, size_t len,
+    void *udata, hbool_t *dirty);
+static herr_t H5EA__cache_dblock_image_len(const void *thing, 
+    size_t *image_len, hbool_t *compressed_ptr, 
+    size_t *compressed_image_len_ptr);
+static herr_t H5EA__cache_dblock_serialize(const H5F_t *f, void *image, size_t len,
+    void *thing);
+static herr_t H5EA__cache_dblock_notify(H5AC_notify_action_t action, void *thing);
+static herr_t H5EA__cache_dblock_free_icr(void *thing);
+static herr_t H5EA__cache_dblock_fsf_size(const void *thing, size_t *fsf_size);
+
+static herr_t H5EA__cache_dblk_page_get_load_size(const void *udata, size_t *image_len);
+static void *H5EA__cache_dblk_page_deserialize(const void *image, size_t len,
+    void *udata, hbool_t *dirty);
+static herr_t H5EA__cache_dblk_page_image_len(const void *thing, 
+    size_t *image_len, hbool_t *compressed_ptr, 
+    size_t *compressed_image_len_ptr);
+static herr_t H5EA__cache_dblk_page_serialize(const H5F_t *f, void *image, size_t len,
+    void *thing);
+static herr_t H5EA__cache_dblk_page_notify(H5AC_notify_action_t action, void *thing);
+static herr_t H5EA__cache_dblk_page_free_icr(void *thing);
 
 
 /*********************/
@@ -117,57 +134,87 @@ static herr_t H5EA__cache_dblk_page_dest(H5F_t *f, H5EA_dblk_page_t *dblk_page);
 
 /* H5EA header inherits cache-like properties from H5AC */
 const H5AC_class_t H5AC_EARRAY_HDR[1] = {{
-    H5AC_EARRAY_HDR_ID,
-    (H5AC_load_func_t)H5EA__cache_hdr_load,
-    (H5AC_flush_func_t)H5EA__cache_hdr_flush,
-    (H5AC_dest_func_t)H5EA__cache_hdr_dest,
-    (H5AC_clear_func_t)H5EA__cache_hdr_clear,
-    (H5AC_notify_func_t)NULL,
-    (H5AC_size_func_t)H5EA__cache_hdr_size,
+    H5AC_EARRAY_HDR_ID,                 /* Metadata client ID */
+    "Extensible Array Header",          /* Metadata client name (for debugging) */
+    H5FD_MEM_EARRAY_HDR,                /* File space memory type for client */
+    H5AC__CLASS_NO_FLAGS_SET,           /* Client class behavior flags */
+    H5EA__cache_hdr_get_load_size,      /* 'get_load_size' callback */
+    H5EA__cache_hdr_deserialize,        /* 'deserialize' callback */
+    H5EA__cache_hdr_image_len,          /* 'image_len' callback */
+    NULL,                               /* 'pre_serialize' callback */
+    H5EA__cache_hdr_serialize,          /* 'serialize' callback */
+    NULL,                               /* 'notify' callback */
+    H5EA__cache_hdr_free_icr,           /* 'free_icr' callback */
+    NULL,				/* 'clear' callback */
+    NULL,                               /* 'fsf_size' callback */
 }};
 
 /* H5EA index block inherits cache-like properties from H5AC */
 const H5AC_class_t H5AC_EARRAY_IBLOCK[1] = {{
-    H5AC_EARRAY_IBLOCK_ID,
-    (H5AC_load_func_t)H5EA__cache_iblock_load,
-    (H5AC_flush_func_t)H5EA__cache_iblock_flush,
-    (H5AC_dest_func_t)H5EA__cache_iblock_dest,
-    (H5AC_clear_func_t)H5EA__cache_iblock_clear,
-    (H5AC_notify_func_t)H5EA__cache_iblock_notify,
-    (H5AC_size_func_t)H5EA__cache_iblock_size,
+    H5AC_EARRAY_IBLOCK_ID,              /* Metadata client ID */
+    "Extensible Array Index Block",     /* Metadata client name (for debugging) */
+    H5FD_MEM_EARRAY_IBLOCK,             /* File space memory type for client */
+    H5AC__CLASS_NO_FLAGS_SET,           /* Client class behavior flags */
+    H5EA__cache_iblock_get_load_size,   /* 'get_load_size' callback */
+    H5EA__cache_iblock_deserialize,     /* 'deserialize' callback */
+    H5EA__cache_iblock_image_len,       /* 'image_len' callback */
+    NULL,                               /* 'pre_serialize' callback */
+    H5EA__cache_iblock_serialize,       /* 'serialize' callback */
+    H5EA__cache_iblock_notify,          /* 'notify' callback */
+    H5EA__cache_iblock_free_icr,        /* 'free_icr' callback */
+    NULL,				/* 'clear' callback */
+    NULL,                               /* 'fsf_size' callback */
 }};
 
 /* H5EA super block inherits cache-like properties from H5AC */
 const H5AC_class_t H5AC_EARRAY_SBLOCK[1] = {{
-    H5AC_EARRAY_SBLOCK_ID,
-    (H5AC_load_func_t)H5EA__cache_sblock_load,
-    (H5AC_flush_func_t)H5EA__cache_sblock_flush,
-    (H5AC_dest_func_t)H5EA__cache_sblock_dest,
-    (H5AC_clear_func_t)H5EA__cache_sblock_clear,
-    (H5AC_notify_func_t)H5EA__cache_sblock_notify,
-    (H5AC_size_func_t)H5EA__cache_sblock_size,
+    H5AC_EARRAY_SBLOCK_ID,              /* Metadata client ID */
+    "Extensible Array Super Block",     /* Metadata client name (for debugging) */
+    H5FD_MEM_EARRAY_SBLOCK,             /* File space memory type for client */
+    H5AC__CLASS_NO_FLAGS_SET,           /* Client class behavior flags */
+    H5EA__cache_sblock_get_load_size,   /* 'get_load_size' callback */
+    H5EA__cache_sblock_deserialize,     /* 'deserialize' callback */
+    H5EA__cache_sblock_image_len,       /* 'image_len' callback */
+    NULL,                               /* 'pre_serialize' callback */
+    H5EA__cache_sblock_serialize,       /* 'serialize' callback */
+    H5EA__cache_sblock_notify,          /* 'notify' callback */
+    H5EA__cache_sblock_free_icr,        /* 'free_icr' callback */
+    NULL,				/* 'clear' callback */
+    NULL,                               /* 'fsf_size' callback */
 }};
 
 /* H5EA data block inherits cache-like properties from H5AC */
 const H5AC_class_t H5AC_EARRAY_DBLOCK[1] = {{
-    H5AC_EARRAY_DBLOCK_ID,
-    (H5AC_load_func_t)H5EA__cache_dblock_load,
-    (H5AC_flush_func_t)H5EA__cache_dblock_flush,
-    (H5AC_dest_func_t)H5EA__cache_dblock_dest,
-    (H5AC_clear_func_t)H5EA__cache_dblock_clear,
-    (H5AC_notify_func_t)H5EA__cache_dblock_notify,
-    (H5AC_size_func_t)H5EA__cache_dblock_size,
+    H5AC_EARRAY_DBLOCK_ID,              /* Metadata client ID */
+    "Extensible Array Data Block",      /* Metadata client name (for debugging) */
+    H5FD_MEM_EARRAY_DBLOCK,             /* File space memory type for client */
+    H5AC__CLASS_NO_FLAGS_SET,           /* Client class behavior flags */
+    H5EA__cache_dblock_get_load_size,   /* 'get_load_size' callback */
+    H5EA__cache_dblock_deserialize,     /* 'deserialize' callback */
+    H5EA__cache_dblock_image_len,       /* 'image_len' callback */
+    NULL,                               /* 'pre_serialize' callback */
+    H5EA__cache_dblock_serialize,       /* 'serialize' callback */
+    H5EA__cache_dblock_notify,          /* 'notify' callback */
+    H5EA__cache_dblock_free_icr,        /* 'free_icr' callback */
+    NULL,				/* 'clear' callback */
+    H5EA__cache_dblock_fsf_size,        /* 'fsf_size' callback */
 }};
 
 /* H5EA data block page inherits cache-like properties from H5AC */
 const H5AC_class_t H5AC_EARRAY_DBLK_PAGE[1] = {{
-    H5AC_EARRAY_DBLK_PAGE_ID,
-    (H5AC_load_func_t)H5EA__cache_dblk_page_load,
-    (H5AC_flush_func_t)H5EA__cache_dblk_page_flush,
-    (H5AC_dest_func_t)H5EA__cache_dblk_page_dest,
-    (H5AC_clear_func_t)H5EA__cache_dblk_page_clear,
-    (H5AC_notify_func_t)H5EA__cache_dblk_page_notify,
-    (H5AC_size_func_t)H5EA__cache_dblk_page_size,
+    H5AC_EARRAY_DBLK_PAGE_ID,           /* Metadata client ID */
+    "Extensible Array Data Block Page", /* Metadata client name (for debugging) */
+    H5FD_MEM_EARRAY_DBLK_PAGE,          /* File space memory type for client */
+    H5AC__CLASS_NO_FLAGS_SET,           /* Client class behavior flags */
+    H5EA__cache_dblk_page_get_load_size, /* 'get_load_size' callback */
+    H5EA__cache_dblk_page_deserialize,  /* 'deserialize' callback */
+    H5EA__cache_dblk_page_image_len,    /* 'image_len' callback */
+    NULL,                               /* 'pre_serialize' callback */
+    H5EA__cache_dblk_page_serialize,    /* 'serialize' callback */
+    H5EA__cache_dblk_page_notify,       /* 'notify' callback */
+    H5EA__cache_dblk_page_free_icr,     /* 'free_icr' callback */
+    NULL,				/* 'clear' callback */
+    NULL,                               /* 'fsf_size' callback */
 }};
 
 
@@ -183,97 +230,111 @@ const H5AC_class_t H5AC_EARRAY_DBLK_PAGE[1] = {{
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5EA__cache_hdr_load
+ * Function:    H5EA__cache_hdr_get_load_size
+ *
+ * Purpose:     Compute the size of the data structure on disk.
+ *
+ * Return:      Non-negative on success/Negative on failure
+ *
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              July 16, 2013
+ *
+ *-------------------------------------------------------------------------
+ */
+BEGIN_FUNC(STATIC, NOERR,
+herr_t, SUCCEED, -,
+H5EA__cache_hdr_get_load_size(const void *_udata, size_t *image_len))
+
+    /* Local variables */
+    const H5EA_hdr_cache_ud_t *udata = (const H5EA_hdr_cache_ud_t *)_udata; /* User data for callback */
+
+    /* Check arguments */
+    HDassert(udata);
+    HDassert(udata->f);
+    HDassert(H5F_addr_defined(udata->addr));
+    HDassert(image_len);
+
+    /* Set the image length size */
+    *image_len = (size_t)H5EA_HEADER_SIZE_FILE(udata->f);
+
+END_FUNC(STATIC)   /* end H5EA__cache_hdr_get_load_size() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5EA__cache_hdr_deserialize
  *
- * Purpose:	Loads an extensible array header from the disk.
+ * Purpose:	Loads a data structure from the disk.
  *
- * Return:	Success:	Pointer to a new extensible array
+ * Return:	Success:	Pointer to a new B-tree.
  *		Failure:	NULL
  *
  * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Aug 26 2008
+ *              koziol@hdfgroup.org
+ *              July 16, 2013
  *
  *-------------------------------------------------------------------------
  */
 BEGIN_FUNC(STATIC, ERR,
-H5EA_hdr_t *, NULL, NULL,
-H5EA__cache_hdr_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata))
+void *, NULL, NULL,
+H5EA__cache_hdr_deserialize(const void *_image, size_t len, void *_udata,
+    hbool_t H5_ATTR_UNUSED *dirty))
 
     /* Local variables */
     H5EA_cls_id_t       id;		/* ID of extensible array class, as found in file */
     H5EA_hdr_t		*hdr = NULL;    /* Extensible array info */
-    size_t		size;           /* Header size */
-    H5WB_t              *wb = NULL;     /* Wrapped buffer for header data */
-    uint8_t             hdr_buf[H5EA_HDR_BUF_SIZE]; /* Buffer for header */
-    uint8_t		*buf;           /* Pointer to header buffer */
-    const uint8_t	*p;             /* Pointer into raw data buffer */
+    H5EA_hdr_cache_ud_t *udata = (H5EA_hdr_cache_ud_t *)_udata;
+    const uint8_t	*image = (const uint8_t *)_image;       /* Pointer into raw data buffer */
     uint32_t            stored_chksum;  /* Stored metadata checksum value */
     uint32_t            computed_chksum; /* Computed metadata checksum value */
 
     /* Check arguments */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
+    HDassert(image);
+    HDassert(udata);
+    HDassert(udata->f);
+    HDassert(H5F_addr_defined(udata->addr));
 
     /* Allocate space for the extensible array data structure */
-    if(NULL == (hdr = H5EA__hdr_alloc(f)))
+    if(NULL == (hdr = H5EA__hdr_alloc(udata->f)))
 	H5E_THROW(H5E_CANTALLOC, "memory allocation failed for extensible array shared header")
 
     /* Set the extensible array header's address */
-    hdr->addr = addr;
-
-    /* Wrap the local buffer for serialized info */
-    if(NULL == (wb = H5WB_wrap(hdr_buf, sizeof(hdr_buf))))
-	H5E_THROW(H5E_CANTINIT, "can't wrap buffer")
-
-    /* Compute the 'base' size of the extensible array header on disk */
-    size = H5EA_HEADER_SIZE_HDR(hdr);
-
-    /* Get a pointer to a buffer that's large enough for serialized header */
-    if(NULL == (buf = (uint8_t *)H5WB_actual(wb, size)))
-	H5E_THROW(H5E_CANTGET, "can't get actual buffer")
-
-    /* Read header from disk */
-    if(H5F_block_read(f, H5FD_MEM_EARRAY_HDR, addr, size, dxpl_id, buf) < 0)
-	H5E_THROW(H5E_READERROR, "can't read extensible array header")
-
-    /* Get temporary pointer to serialized header */
-    p = buf;
+    hdr->addr = udata->addr;
 
     /* Magic number */
-    if(HDmemcmp(p, H5EA_HDR_MAGIC, (size_t)H5_SIZEOF_MAGIC))
+    if(HDmemcmp(image, H5EA_HDR_MAGIC, (size_t)H5_SIZEOF_MAGIC))
 	H5E_THROW(H5E_BADVALUE, "wrong extensible array header signature")
-    p += H5_SIZEOF_MAGIC;
+    image += H5_SIZEOF_MAGIC;
 
     /* Version */
-    if(*p++ != H5EA_HDR_VERSION)
+    if(*image++ != H5EA_HDR_VERSION)
 	H5E_THROW(H5E_VERSION, "wrong extensible array header version")
 
     /* Extensible array class */
-    id = (H5EA_cls_id_t)*p++;
+    id = (H5EA_cls_id_t)*image++;
     if(id >= H5EA_NUM_CLS_ID)
 	H5E_THROW(H5E_BADTYPE, "incorrect extensible array class")
     hdr->cparam.cls = H5EA_client_class_g[id];
 
     /* General array creation/configuration information */
-    hdr->cparam.raw_elmt_size = *p++;          /* Element size in file (in bytes) */
-    hdr->cparam.max_nelmts_bits = *p++;        /* Log2(Max. # of elements in array) - i.e. # of bits needed to store max. # of elements */
-    hdr->cparam.idx_blk_elmts = *p++;          /* # of elements to store in index block */
-    hdr->cparam.data_blk_min_elmts = *p++;     /* Min. # of elements per data block */
-    hdr->cparam.sup_blk_min_data_ptrs = *p++;  /* Min. # of data block pointers for a super block */
-    hdr->cparam.max_dblk_page_nelmts_bits = *p++;  /* Log2(Max. # of elements in data block page) - i.e. # of bits needed to store max. # of elements in data block page */
+    hdr->cparam.raw_elmt_size = *image++;          /* Element size in file (in bytes) */
+    hdr->cparam.max_nelmts_bits = *image++;        /* Log2(Max. # of elements in array) - i.e. # of bits needed to store max. # of elements */
+    hdr->cparam.idx_blk_elmts = *image++;          /* # of elements to store in index block */
+    hdr->cparam.data_blk_min_elmts = *image++;     /* Min. # of elements per data block */
+    hdr->cparam.sup_blk_min_data_ptrs = *image++;  /* Min. # of data block pointers for a super block */
+    hdr->cparam.max_dblk_page_nelmts_bits = *image++;  /* Log2(Max. # of elements in data block page) - i.e. # of bits needed to store max. # of elements in data block page */
 
     /* Array statistics */
-    hdr->stats.computed.hdr_size = size;                        /* Size of header in file */
-    H5F_DECODE_LENGTH(f, p, hdr->stats.stored.nsuper_blks);    /* Number of super blocks created */
-    H5F_DECODE_LENGTH(f, p, hdr->stats.stored.super_blk_size); /* Size of super blocks created */
-    H5F_DECODE_LENGTH(f, p, hdr->stats.stored.ndata_blks);     /* Number of data blocks created */
-    H5F_DECODE_LENGTH(f, p, hdr->stats.stored.data_blk_size);  /* Size of data blocks created */
-    H5F_DECODE_LENGTH(f, p, hdr->stats.stored.max_idx_set);    /* Max. index set (+1) */
-    H5F_DECODE_LENGTH(f, p, hdr->stats.stored.nelmts);         /* Number of elements 'realized' */
+    hdr->stats.computed.hdr_size = len;                        /* Size of header in file */
+    H5F_DECODE_LENGTH(udata->f, image, hdr->stats.stored.nsuper_blks);    /* Number of super blocks created */
+    H5F_DECODE_LENGTH(udata->f, image, hdr->stats.stored.super_blk_size); /* Size of super blocks created */
+    H5F_DECODE_LENGTH(udata->f, image, hdr->stats.stored.ndata_blks);     /* Number of data blocks created */
+    H5F_DECODE_LENGTH(udata->f, image, hdr->stats.stored.data_blk_size);  /* Size of data blocks created */
+    H5F_DECODE_LENGTH(udata->f, image, hdr->stats.stored.max_idx_set);    /* Max. index set (+1) */
+    H5F_DECODE_LENGTH(udata->f, image, hdr->stats.stored.nelmts);         /* Number of elements 'realized' */
 
     /* Internal information */
-    H5F_addr_decode(f, &p, &hdr->idx_blk_addr); /* Address of index block */
+    H5F_addr_decode(udata->f, &image, &hdr->idx_blk_addr); /* Address of index block */
 
     /* Index block statistics */
     if(H5F_addr_defined(hdr->idx_blk_addr)) {
@@ -298,26 +359,26 @@ H5EA__cache_hdr_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata))
 
     /* Sanity check */
     /* (allow for checksum not decoded yet) */
-    HDassert((size_t)(p - buf) == (size - H5EA_SIZEOF_CHKSUM));
+    HDassert((size_t)(image - (const uint8_t *)_image) == (len - H5EA_SIZEOF_CHKSUM));
 
     /* Compute checksum on entire header */
     /* (including the filter information, if present) */
-    computed_chksum = H5_checksum_metadata(buf, (size_t)(p - buf), 0);
+    computed_chksum = H5_checksum_metadata(_image, (size_t)(image - (const uint8_t *)_image), 0);
 
     /* Metadata checksum */
-    UINT32DECODE(p, stored_chksum);
-
-    /* Sanity check */
-    HDassert((size_t)(p - buf) == size);
+    UINT32DECODE(image, stored_chksum);
 
     /* Verify checksum */
     if(stored_chksum != computed_chksum)
 	H5E_THROW(H5E_BADVALUE, "incorrect metadata checksum for extensible array header")
 
+    /* Sanity check */
+    HDassert((size_t)(image - (const uint8_t *)_image) == len);
+
     /* Finish initializing extensible array header */
-    if(H5EA__hdr_init(hdr, udata) < 0)
+    if(H5EA__hdr_init(hdr, udata->ctx_udata) < 0)
 	H5E_THROW(H5E_CANTINIT, "initialization failed for extensible array header")
-    HDassert(hdr->size == size);
+    HDassert(hdr->size == len);
 
     /* Set return value */
     ret_value = hdr;
@@ -325,263 +386,211 @@ H5EA__cache_hdr_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata))
 CATCH
 
     /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-	H5E_THROW(H5E_CLOSEERROR, "can't close wrapped buffer")
     if(!ret_value)
         if(hdr && H5EA__hdr_dest(hdr) < 0)
             H5E_THROW(H5E_CANTFREE, "unable to destroy extensible array header")
 
-END_FUNC(STATIC)   /* end H5EA__cache_hdr_load() */
+END_FUNC(STATIC)   /* end H5EA__cache_hdr_deserialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5EA__cache_hdr_flush
+ * Function:    H5EA__cache_hdr_image_len
  *
- * Purpose:	Flushes a dirty extensible array header to disk.
+ * Purpose:     Compute the size of the data structure on disk.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Aug 26 2008
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              July 16, 2013
  *
  *-------------------------------------------------------------------------
  */
-BEGIN_FUNC(STATIC, ERR,
-herr_t, SUCCEED, FAIL,
-H5EA__cache_hdr_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr,
-    H5EA_hdr_t *hdr, unsigned H5_ATTR_UNUSED * flags_ptr))
+BEGIN_FUNC(STATIC, NOERR,
+herr_t, SUCCEED, -,
+H5EA__cache_hdr_image_len(const void *_thing, size_t *image_len,
+    hbool_t H5_ATTR_UNUSED *compressed_ptr, size_t H5_ATTR_UNUSED *compressed_image_len_ptr))
 
-    H5WB_t *wb = NULL;                  /* Wrapped buffer for header data */
-    uint8_t hdr_buf[H5EA_HDR_BUF_SIZE]; /* Buffer for header */
+    /* Local variables */
+    const H5EA_hdr_t *hdr = (const H5EA_hdr_t *)_thing;      /* Pointer to the object */
 
-    /* check arguments */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
+    /* Check arguments */
     HDassert(hdr);
+    HDassert(image_len);
 
-    if(hdr->cache_info.is_dirty) {
-        uint8_t	*buf;           /* Temporary raw data buffer */
-        uint8_t *p;             /* Pointer into raw data buffer */
-        size_t	size;           /* Header size on disk */
-        uint32_t metadata_chksum; /* Computed metadata checksum value */
-
-        /* Wrap the local buffer for serialized header info */
-        if(NULL == (wb = H5WB_wrap(hdr_buf, sizeof(hdr_buf))))
-            H5E_THROW(H5E_CANTINIT, "can't wrap buffer")
-
-        /* Compute the size of the array header on disk */
-        size = hdr->size;
-
-        /* Get a pointer to a buffer that's large enough for serialized header */
-        if(NULL == (buf = (uint8_t *)H5WB_actual(wb, size)))
-            H5E_THROW(H5E_CANTGET, "can't get actual buffer")
+    /* Set the image length size */
+    *image_len = hdr->size;
 
-        /* Get temporary pointer to serialized header */
-        p = buf;
+END_FUNC(STATIC)   /* end H5EA__cache_hdr_image_len() */
 
-        /* Magic number */
-        HDmemcpy(p, H5EA_HDR_MAGIC, (size_t)H5_SIZEOF_MAGIC);
-        p += H5_SIZEOF_MAGIC;
-
-        /* Version # */
-        *p++ = H5EA_HDR_VERSION;
+
+/*-------------------------------------------------------------------------
+ * Function:	H5EA__cache_hdr_serialize
+ *
+ * Purpose:	Flushes a dirty object to disk.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              July 16, 2013
+ *
+ *-------------------------------------------------------------------------
+ */
+BEGIN_FUNC(STATIC, NOERR,
+herr_t, SUCCEED, -,
+H5EA__cache_hdr_serialize(const H5F_t *f, void *_image, size_t H5_ATTR_UNUSED len,
+    void *_thing))
 
-        /* Extensible array type */
-        *p++ = hdr->cparam.cls->id;
+    /* Local variables */
+    H5EA_hdr_t *hdr = (H5EA_hdr_t *)_thing;      /* Pointer to the extensible array header */
+    uint8_t *image = (uint8_t *)_image;         /* Pointer into raw data buffer */
+    uint32_t metadata_chksum;   /* Computed metadata checksum value */
 
-        /* General array creation/configuration information */
-        *p++ = hdr->cparam.raw_elmt_size;          /* Element size in file (in bytes) */
-        *p++ = hdr->cparam.max_nelmts_bits;        /* Log2(Max. # of elements in array) - i.e. # of bits needed to store max. # of elements */
-        *p++ = hdr->cparam.idx_blk_elmts;          /* # of elements to store in index block */
-        *p++ = hdr->cparam.data_blk_min_elmts;     /* Min. # of elements per data block */
-        *p++ = hdr->cparam.sup_blk_min_data_ptrs;  /* Min. # of data block pointers for a super block */
-        *p++ = hdr->cparam.max_dblk_page_nelmts_bits;  /* Log2(Max. # of elements in data block page) - i.e. # of bits needed to store max. # of elements in data block page */
+    /* check arguments */
+    HDassert(f);
+    HDassert(image);
+    HDassert(hdr);
 
-        /* Array statistics */
-        H5F_ENCODE_LENGTH(f, p, hdr->stats.stored.nsuper_blks);    /* Number of super blocks created */
-        H5F_ENCODE_LENGTH(f, p, hdr->stats.stored.super_blk_size); /* Size of super blocks created */
-        H5F_ENCODE_LENGTH(f, p, hdr->stats.stored.ndata_blks);     /* Number of data blocks created */
-        H5F_ENCODE_LENGTH(f, p, hdr->stats.stored.data_blk_size);  /* Size of data blocks created */
-        H5F_ENCODE_LENGTH(f, p, hdr->stats.stored.max_idx_set);    /* Max. index set (+1) */
-        H5F_ENCODE_LENGTH(f, p, hdr->stats.stored.nelmts);         /* Number of elements 'realized' */
+    /* Magic number */
+    HDmemcpy(image, H5EA_HDR_MAGIC, (size_t)H5_SIZEOF_MAGIC);
+    image += H5_SIZEOF_MAGIC;
 
-        /* Internal information */
-        H5F_addr_encode(f, &p, hdr->idx_blk_addr);  /* Address of index block */
+    /* Version # */
+    *image++ = H5EA_HDR_VERSION;
 
-        /* Compute metadata checksum */
-        metadata_chksum = H5_checksum_metadata(buf, (size_t)(p - buf), 0);
+    /* Extensible array type */
+    *image++ = hdr->cparam.cls->id;
 
-        /* Metadata checksum */
-        UINT32ENCODE(p, metadata_chksum);
+    /* General array creation/configuration information */
+    *image++ = hdr->cparam.raw_elmt_size;          /* Element size in file (in bytes) */
+    *image++ = hdr->cparam.max_nelmts_bits;        /* Log2(Max. # of elements in array) - i.e. # of bits needed to store max. # of elements */
+    *image++ = hdr->cparam.idx_blk_elmts;          /* # of elements to store in index block */
+    *image++ = hdr->cparam.data_blk_min_elmts;     /* Min. # of elements per data block */
+    *image++ = hdr->cparam.sup_blk_min_data_ptrs;  /* Min. # of data block pointers for a super block */
+    *image++ = hdr->cparam.max_dblk_page_nelmts_bits;  /* Log2(Max. # of elements in data block page) - i.e. # of bits needed to store max. # of elements in data block page */
 
-	/* Write the array header. */
-        HDassert((size_t)(p - buf) == size);
-	if(H5F_block_write(f, H5FD_MEM_EARRAY_HDR, addr, size, dxpl_id, buf) < 0)
-            H5E_THROW(H5E_WRITEERROR, "unable to save extensible array header to disk")
+    /* Array statistics */
+    H5F_ENCODE_LENGTH(f, image, hdr->stats.stored.nsuper_blks);    /* Number of super blocks created */
+    H5F_ENCODE_LENGTH(f, image, hdr->stats.stored.super_blk_size); /* Size of super blocks created */
+    H5F_ENCODE_LENGTH(f, image, hdr->stats.stored.ndata_blks);     /* Number of data blocks created */
+    H5F_ENCODE_LENGTH(f, image, hdr->stats.stored.data_blk_size);  /* Size of data blocks created */
+    H5F_ENCODE_LENGTH(f, image, hdr->stats.stored.max_idx_set);    /* Max. index set (+1) */
+    H5F_ENCODE_LENGTH(f, image, hdr->stats.stored.nelmts);         /* Number of elements 'realized' */
 
-	hdr->cache_info.is_dirty = FALSE;
-    } /* end if */
+    /* Internal information */
+    H5F_addr_encode(f, &image, hdr->idx_blk_addr);  /* Address of index block */
 
-    if(destroy)
-        if(H5EA__cache_hdr_dest(f, hdr) < 0)
-            H5E_THROW(H5E_CANTFREE, "unable to destroy extensible array header")
+    /* Compute metadata checksum */
+    metadata_chksum = H5_checksum_metadata(_image, (size_t)(image - (uint8_t *)_image), 0);
 
-CATCH
+    /* Metadata checksum */
+    UINT32ENCODE(image, metadata_chksum);
 
-    /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-	H5E_THROW(H5E_CLOSEERROR, "can't close wrapped buffer")
+    /* Sanity check */
+    HDassert((size_t)(image - (uint8_t *)_image) == len);
 
-END_FUNC(STATIC)   /* end H5EA__cache_hdr_flush() */
+END_FUNC(STATIC)   /* end H5EA__cache_hdr_serialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5EA__cache_hdr_clear
+ * Function:	H5EA__cache_hdr_free_icr
  *
- * Purpose:	Mark a extensible array header in memory as non-dirty.
+ * Purpose:	Destroy/release an "in core representation" of a data
+ *              structure
  *
  * Return:	Non-negative on success/Negative on failure
  *
  * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Aug 26 2008
+ *              koziol@hdfgroup.org
+ *              July 16, 2013
  *
  *-------------------------------------------------------------------------
  */
 BEGIN_FUNC(STATIC, ERR,
 herr_t, SUCCEED, FAIL,
-H5EA__cache_hdr_clear(H5F_t *f, H5EA_hdr_t *hdr, hbool_t destroy))
+H5EA__cache_hdr_free_icr(void *thing))
 
-    /* Sanity check */
-    HDassert(hdr);
-
-    /* Reset the dirty flag.  */
-    hdr->cache_info.is_dirty = FALSE;
+    /* Check arguments */
+    HDassert(thing);
 
-    if(destroy)
-        if(H5EA__cache_hdr_dest(f, hdr) < 0)
-            H5E_THROW(H5E_CANTFREE, "unable to destroy extensible array header")
+    /* Release the extensible array header */
+    if(H5EA__hdr_dest((H5EA_hdr_t *)thing) < 0)
+        H5E_THROW(H5E_CANTFREE, "can't free extensible array header")
 
 CATCH
 
-END_FUNC(STATIC)   /* end H5EA__cache_hdr_clear() */
+END_FUNC(STATIC)   /* end H5EA__cache_hdr_free_icr() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5EA__cache_hdr_size
+ * Function:    H5EA__cache_iblock_get_load_size
  *
- * Purpose:	Compute the size in bytes of a extensible array header
- *		on disk, and return it in *size_ptr.  On failure,
- *		the value of *size_ptr is undefined.
+ * Purpose:     Compute the size of the data structure on disk.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Aug 26 2008
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              July 17, 2013
  *
  *-------------------------------------------------------------------------
  */
-/* ARGSUSED */
 BEGIN_FUNC(STATIC, NOERR,
 herr_t, SUCCEED, -,
-H5EA__cache_hdr_size(const H5F_t H5_ATTR_UNUSED *f, const H5EA_hdr_t *hdr,
-    size_t *size_ptr))
-
-    /* Sanity check */
-    HDassert(f);
-    HDassert(hdr);
-    HDassert(size_ptr);
-
-    /* Set size value */
-    *size_ptr = hdr->size;
-
-END_FUNC(STATIC)   /* end H5EA__cache_hdr_size() */
+H5EA__cache_iblock_get_load_size(const void *_udata, size_t *image_len))
 
-
-/*-------------------------------------------------------------------------
- * Function:	H5EA__cache_hdr_dest
- *
- * Purpose:	Destroys an extensible array header in memory.
- *
- * Return:	Non-negative on success/Negative on failure
- *
- * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Aug 26 2008
- *
- *-------------------------------------------------------------------------
- */
-/* ARGSUSED */
-BEGIN_FUNC(STATIC, ERR,
-herr_t, SUCCEED, FAIL,
-H5EA__cache_hdr_dest(H5F_t *f, H5EA_hdr_t *hdr))
+    /* Local variables */
+    const H5EA_hdr_t *hdr = (const H5EA_hdr_t *)_udata; /* User data for callback */
+    H5EA_iblock_t iblock;           /* Fake index block for computing size */
 
     /* Check arguments */
-    HDassert(f);
     HDassert(hdr);
+    HDassert(image_len);
 
-    /* Verify that header is clean */
-    HDassert(hdr->cache_info.is_dirty == FALSE);
-
-    /* If we're going to free the space on disk, the address must be valid */
-    HDassert(!hdr->cache_info.free_file_space_on_destroy || H5F_addr_defined(hdr->cache_info.addr));
-
-    /* Check for freeing file space for extensible array header */
-    if(hdr->cache_info.free_file_space_on_destroy) {
-        /* Sanity check address */
-        HDassert(H5F_addr_eq(hdr->addr, hdr->cache_info.addr));
-
-        /* Release the space on disk */
-        /* (XXX: Nasty usage of internal DXPL value! -QAK) */
-        if(H5MF_xfree(f, H5FD_MEM_EARRAY_HDR, H5AC_dxpl_id, hdr->cache_info.addr, (hsize_t)hdr->size) < 0)
-            H5E_THROW(H5E_CANTFREE, "unable to free extensible array header")
-    } /* end if */
+    /* Set up fake index block for computing size on disk */
+    HDmemset(&iblock, 0, sizeof(iblock));
+    iblock.hdr = (H5EA_hdr_t *)hdr;     /* Casting away 'const' OK - QAK */
+    iblock.nsblks = H5EA_SBLK_FIRST_IDX(hdr->cparam.sup_blk_min_data_ptrs);
+    iblock.ndblk_addrs = 2 * ((size_t)hdr->cparam.sup_blk_min_data_ptrs - 1);
+    iblock.nsblk_addrs = hdr->nsblks - iblock.nsblks;
 
-    /* Release the extensible array header */
-    if(H5EA__hdr_dest(hdr) < 0)
-        H5E_THROW(H5E_CANTFREE, "can't free extensible array header")
-
-CATCH
+    /* Set the image length size */
+    *image_len = (size_t)H5EA_IBLOCK_SIZE(&iblock);
 
-END_FUNC(STATIC)   /* end H5EA__cache_hdr_dest() */
+END_FUNC(STATIC)   /* end H5EA__cache_iblock_get_load_size() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5EA__cache_iblock_load
+ * Function:	H5EA__cache_iblock_deserialize
  *
- * Purpose:	Loads an extensible array index block from the disk.
+ * Purpose:	Loads a data structure from the disk.
  *
- * Return:	Success:	Pointer to a new extensible array index block
+ * Return:	Success:	Pointer to a new B-tree.
  *		Failure:	NULL
  *
  * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Sep  9 2008
+ *              koziol@hdfgroup.org
+ *              July 17, 2013
  *
  *-------------------------------------------------------------------------
  */
 BEGIN_FUNC(STATIC, ERR,
-H5EA_iblock_t *, NULL, NULL,
-H5EA__cache_iblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata))
+void *, NULL, NULL,
+H5EA__cache_iblock_deserialize(const void *_image, size_t len,
+    void *_udata, hbool_t H5_ATTR_UNUSED *dirty))
 
     /* Local variables */
-    H5EA_hdr_t    *hdr = (H5EA_hdr_t *)_udata;   /* Shared extensible array information */
     H5EA_iblock_t	*iblock = NULL; /* Index block info */
-    size_t		size;           /* Index block size */
-    H5WB_t              *wb = NULL;     /* Wrapped buffer for index block data */
-    uint8_t             iblock_buf[H5EA_IBLOCK_BUF_SIZE]; /* Buffer for index block */
-    uint8_t		*buf;           /* Pointer to index block buffer */
-    const uint8_t	*p;             /* Pointer into raw data buffer */
+    H5EA_hdr_t *hdr = (H5EA_hdr_t *)_udata;     /* User data for callback */
+    const uint8_t	*image = (const uint8_t *)_image;       /* Pointer into raw data buffer */
     uint32_t            stored_chksum;  /* Stored metadata checksum value */
     uint32_t            computed_chksum; /* Computed metadata checksum value */
     haddr_t             arr_addr;       /* Address of array header in the file */
     size_t              u;              /* Local index variable */
 
-    /* Sanity check */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
+    /* Check arguments */
+    HDassert(image);
     HDassert(hdr);
 
     /* Allocate the extensible array index block */
@@ -589,41 +598,23 @@ H5EA__cache_iblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata))
 	H5E_THROW(H5E_CANTALLOC, "memory allocation failed for extensible array index block")
 
     /* Set the extensible array index block's address */
-    iblock->addr = addr;
-
-    /* Wrap the local buffer for serialized info */
-    if(NULL == (wb = H5WB_wrap(iblock_buf, sizeof(iblock_buf))))
-	H5E_THROW(H5E_CANTINIT, "can't wrap buffer")
-
-    /* Compute the size of the extensible array index block on disk */
-    size = H5EA_IBLOCK_SIZE(iblock);
-
-    /* Get a pointer to a buffer that's large enough for serialized info */
-    if(NULL == (buf = (uint8_t *)H5WB_actual(wb, size)))
-	H5E_THROW(H5E_CANTGET, "can't get actual buffer")
-
-    /* Read index block from disk */
-    if(H5F_block_read(f, H5FD_MEM_EARRAY_IBLOCK, addr, size, dxpl_id, buf) < 0)
-	H5E_THROW(H5E_READERROR, "can't read extensible array index block")
-
-    /* Get temporary pointer to serialized header */
-    p = buf;
+    iblock->addr = hdr->idx_blk_addr;
 
     /* Magic number */
-    if(HDmemcmp(p, H5EA_IBLOCK_MAGIC, (size_t)H5_SIZEOF_MAGIC))
+    if(HDmemcmp(image, H5EA_IBLOCK_MAGIC, (size_t)H5_SIZEOF_MAGIC))
 	H5E_THROW(H5E_BADVALUE, "wrong extensible array index block signature")
-    p += H5_SIZEOF_MAGIC;
+    image += H5_SIZEOF_MAGIC;
 
     /* Version */
-    if(*p++ != H5EA_IBLOCK_VERSION)
+    if(*image++ != H5EA_IBLOCK_VERSION)
 	H5E_THROW(H5E_VERSION, "wrong extensible array index block version")
 
     /* Extensible array type */
-    if(*p++ != (uint8_t)hdr->cparam.cls->id)
+    if(*image++ != (uint8_t)hdr->cparam.cls->id)
 	H5E_THROW(H5E_BADTYPE, "incorrect extensible array class")
 
     /* Address of header for array that owns this block (just for file integrity checks) */
-    H5F_addr_decode(f, &p, &arr_addr);
+    H5F_addr_decode(hdr->f, &image, &arr_addr);
     if(H5F_addr_ne(arr_addr, hdr->addr))
 	H5E_THROW(H5E_BADVALUE, "wrong extensible array header address")
 
@@ -632,40 +623,40 @@ H5EA__cache_iblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata))
     /* Decode elements in index block */
     if(hdr->cparam.idx_blk_elmts > 0) {
         /* Convert from raw elements on disk into native elements in memory */
-        if((hdr->cparam.cls->decode)(p, iblock->elmts, (size_t)hdr->cparam.idx_blk_elmts, hdr->cb_ctx) < 0)
+        if((hdr->cparam.cls->decode)(image, iblock->elmts, (size_t)hdr->cparam.idx_blk_elmts, hdr->cb_ctx) < 0)
             H5E_THROW(H5E_CANTDECODE, "can't decode extensible array index elements")
-        p += (hdr->cparam.idx_blk_elmts * hdr->cparam.raw_elmt_size);
+        image += (hdr->cparam.idx_blk_elmts * hdr->cparam.raw_elmt_size);
     } /* end if */
 
     /* Decode data block addresses in index block */
     if(iblock->ndblk_addrs > 0) {
         /* Decode addresses of data blocks in index block */
         for(u = 0; u < iblock->ndblk_addrs; u++)
-            H5F_addr_decode(f, &p, &iblock->dblk_addrs[u]);
+            H5F_addr_decode(hdr->f, &image, &iblock->dblk_addrs[u]);
     } /* end if */
 
     /* Decode super block addresses in index block */
     if(iblock->nsblk_addrs > 0) {
         /* Decode addresses of super blocks in index block */
         for(u = 0; u < iblock->nsblk_addrs; u++)
-            H5F_addr_decode(f, &p, &iblock->sblk_addrs[u]);
+            H5F_addr_decode(hdr->f, &image, &iblock->sblk_addrs[u]);
     } /* end if */
 
     /* Sanity check */
     /* (allow for checksum not decoded yet) */
-    HDassert((size_t)(p - buf) == (size - H5EA_SIZEOF_CHKSUM));
+    HDassert((size_t)(image - (const uint8_t *)_image) == (len - H5EA_SIZEOF_CHKSUM));
 
     /* Save the index block's size */
-    iblock->size = size;
+    iblock->size = len;
 
     /* Compute checksum on index block */
-    computed_chksum = H5_checksum_metadata(buf, (size_t)(p - buf), 0);
+    computed_chksum = H5_checksum_metadata((const uint8_t *)_image, (size_t)(image - (const uint8_t *)_image), 0);
 
     /* Metadata checksum */
-    UINT32DECODE(p, stored_chksum);
+    UINT32DECODE(image, stored_chksum);
 
     /* Sanity check */
-    HDassert((size_t)(p - buf) == iblock->size);
+    HDassert((size_t)(image - (const uint8_t *)_image) == iblock->size);
 
     /* Verify checksum */
     if(stored_chksum != computed_chksum)
@@ -677,161 +668,128 @@ H5EA__cache_iblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata))
 CATCH
 
     /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-	H5E_THROW(H5E_CLOSEERROR, "can't close wrapped buffer")
     if(!ret_value)
         if(iblock && H5EA__iblock_dest(iblock) < 0)
             H5E_THROW(H5E_CANTFREE, "unable to destroy extensible array index block")
 
-END_FUNC(STATIC)   /* end H5EA__cache_iblock_load() */
+END_FUNC(STATIC)   /* end H5EA__cache_iblock_deserialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5EA__cache_iblock_flush
+ * Function:    H5EA__cache_iblock_image_len
+ *
+ * Purpose:     Compute the size of the data structure on disk.
+ *
+ * Return:      Non-negative on success/Negative on failure
  *
- * Purpose:	Flushes a dirty extensible array index block to disk.
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              July 17, 2013
+ *
+ *-------------------------------------------------------------------------
+ */
+BEGIN_FUNC(STATIC, NOERR,
+herr_t, SUCCEED, -,
+H5EA__cache_iblock_image_len(const void *_thing, size_t *image_len,
+    hbool_t H5_ATTR_UNUSED *compressed_ptr, size_t H5_ATTR_UNUSED *compressed_image_len_ptr))
+
+    /* Local variables */
+    const H5EA_iblock_t *iblock = (const H5EA_iblock_t *)_thing;      /* Pointer to the object */
+
+    /* Check arguments */
+    HDassert(iblock);
+    HDassert(image_len);
+
+    /* Set the image length size */
+    *image_len = iblock->size;
+
+END_FUNC(STATIC)   /* end H5EA__cache_iblock_image_len() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5EA__cache_iblock_serialize
+ *
+ * Purpose:	Flushes a dirty object to disk.
  *
  * Return:	Non-negative on success/Negative on failure
  *
  * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Sep  9 2008
+ *              koziol@hdfgroup.org
+ *              July 17, 2013
  *
  *-------------------------------------------------------------------------
  */
 BEGIN_FUNC(STATIC, ERR,
 herr_t, SUCCEED, FAIL,
-H5EA__cache_iblock_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr,
-    H5EA_iblock_t *iblock, unsigned H5_ATTR_UNUSED * flags_ptr))
+H5EA__cache_iblock_serialize(const H5F_t *f, void *_image, size_t H5_ATTR_UNUSED len,
+    void *_thing))
 
     /* Local variables */
-    H5WB_t *wb = NULL;                  /* Wrapped buffer for serializing data */
-    uint8_t ser_buf[H5EA_IBLOCK_BUF_SIZE]; /* Serialization buffer */
+    H5EA_iblock_t *iblock = (H5EA_iblock_t *)_thing;      /* Pointer to the object to serialize */
+    uint8_t *image = (uint8_t *)_image;         /* Pointer into raw data buffer */
+    uint32_t metadata_chksum;   /* Computed metadata checksum value */
 
-    /* Sanity check */
+    /* check arguments */
     HDassert(f);
-    HDassert(H5F_addr_defined(addr));
+    HDassert(image);
     HDassert(iblock);
     HDassert(iblock->hdr);
 
-    if(iblock->cache_info.is_dirty) {
-        uint8_t	*buf;           /* Temporary raw data buffer */
-        uint8_t *p;             /* Pointer into raw data buffer */
-        size_t	size;           /* Index block size on disk */
-        uint32_t metadata_chksum; /* Computed metadata checksum value */
-
-        /* Wrap the local buffer for serialized info */
-        if(NULL == (wb = H5WB_wrap(ser_buf, sizeof(ser_buf))))
-            H5E_THROW(H5E_CANTINIT, "can't wrap buffer")
-
-        /* Compute the size of the index block on disk */
-        size = iblock->size;
-
-        /* Get a pointer to a buffer that's large enough for serialized info */
-        if(NULL == (buf = (uint8_t *)H5WB_actual(wb, size)))
-            H5E_THROW(H5E_CANTGET, "can't get actual buffer")
-
-        /* Get temporary pointer to serialized info */
-        p = buf;
+    /* Get temporary pointer to serialized info */
 
-        /* Magic number */
-        HDmemcpy(p, H5EA_IBLOCK_MAGIC, (size_t)H5_SIZEOF_MAGIC);
-        p += H5_SIZEOF_MAGIC;
-
-        /* Version # */
-        *p++ = H5EA_IBLOCK_VERSION;
-
-        /* Extensible array type */
-        *p++ = iblock->hdr->cparam.cls->id;
-
-        /* Address of array header for array which owns this block */
-        H5F_addr_encode(f, &p, iblock->hdr->addr);
-
-        /* Internal information */
-
-        /* Encode elements in index block */
-        if(iblock->hdr->cparam.idx_blk_elmts > 0) {
-            /* Convert from native elements in memory into raw elements on disk */
-            if((iblock->hdr->cparam.cls->encode)(p, iblock->elmts, (size_t)iblock->hdr->cparam.idx_blk_elmts, iblock->hdr->cb_ctx) < 0)
-                H5E_THROW(H5E_CANTENCODE, "can't encode extensible array index elements")
-            p += (iblock->hdr->cparam.idx_blk_elmts * iblock->hdr->cparam.raw_elmt_size);
-        } /* end if */
-
-        /* Encode data block addresses in index block */
-        if(iblock->ndblk_addrs > 0) {
-            size_t u;               /* Local index variable */
+    /* Magic number */
+    HDmemcpy(image, H5EA_IBLOCK_MAGIC, (size_t)H5_SIZEOF_MAGIC);
+    image += H5_SIZEOF_MAGIC;
 
-            /* Encode addresses of data blocks in index block */
-            for(u = 0; u < iblock->ndblk_addrs; u++)
-                H5F_addr_encode(f, &p, iblock->dblk_addrs[u]);
-        } /* end if */
+    /* Version # */
+    *image++ = H5EA_IBLOCK_VERSION;
 
-        /* Encode data block addresses in index block */
-        if(iblock->nsblk_addrs > 0) {
-            size_t u;               /* Local index variable */
+    /* Extensible array type */
+    *image++ = iblock->hdr->cparam.cls->id;
 
-            /* Encode addresses of super blocks in index block */
-            for(u = 0; u < iblock->nsblk_addrs; u++)
-                H5F_addr_encode(f, &p, iblock->sblk_addrs[u]);
-        } /* end if */
+    /* Address of array header for array which owns this block */
+    H5F_addr_encode(f, &image, iblock->hdr->addr);
 
-        /* Compute metadata checksum */
-        metadata_chksum = H5_checksum_metadata(buf, (size_t)(p - buf), 0);
+    /* Internal information */
 
-        /* Metadata checksum */
-        UINT32ENCODE(p, metadata_chksum);
+    /* Encode elements in index block */
+    if(iblock->hdr->cparam.idx_blk_elmts > 0) {
+        /* Convert from native elements in memory into raw elements on disk */
+        if((iblock->hdr->cparam.cls->encode)(image, iblock->elmts, (size_t)iblock->hdr->cparam.idx_blk_elmts, iblock->hdr->cb_ctx) < 0)
+            H5E_THROW(H5E_CANTENCODE, "can't encode extensible array index elements")
+        image += (iblock->hdr->cparam.idx_blk_elmts * iblock->hdr->cparam.raw_elmt_size);
+    } /* end if */
 
-	/* Write the index block */
-        HDassert((size_t)(p - buf) == size);
-	if(H5F_block_write(f, H5FD_MEM_EARRAY_IBLOCK, addr, size, dxpl_id, buf) < 0)
-            H5E_THROW(H5E_WRITEERROR, "unable to save extensible array index block to disk")
+    /* Encode data block addresses in index block */
+    if(iblock->ndblk_addrs > 0) {
+        size_t u;               /* Local index variable */
 
-	iblock->cache_info.is_dirty = FALSE;
+        /* Encode addresses of data blocks in index block */
+        for(u = 0; u < iblock->ndblk_addrs; u++)
+            H5F_addr_encode(f, &image, iblock->dblk_addrs[u]);
     } /* end if */
 
-    if(destroy)
-        if(H5EA__cache_iblock_dest(f, iblock) < 0)
-            H5E_THROW(H5E_CANTFREE, "unable to destroy extensible array index block")
-
-CATCH
+    /* Encode data block addresses in index block */
+    if(iblock->nsblk_addrs > 0) {
+        size_t u;               /* Local index variable */
 
-    /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-	H5E_THROW(H5E_CLOSEERROR, "can't close wrapped buffer")
+        /* Encode addresses of super blocks in index block */
+        for(u = 0; u < iblock->nsblk_addrs; u++)
+            H5F_addr_encode(f, &image, iblock->sblk_addrs[u]);
+    } /* end if */
 
-END_FUNC(STATIC)   /* end H5EA__cache_iblock_flush() */
+    /* Compute metadata checksum */
+    metadata_chksum = H5_checksum_metadata(_image, (size_t)(image - (uint8_t *)_image), 0);
 
-
-/*-------------------------------------------------------------------------
- * Function:	H5EA__cache_iblock_clear
- *
- * Purpose:	Mark a extensible array index block in memory as non-dirty.
- *
- * Return:	Non-negative on success/Negative on failure
- *
- * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Sept 9 2008
- *
- *-------------------------------------------------------------------------
- */
-BEGIN_FUNC(STATIC, ERR,
-herr_t, SUCCEED, FAIL,
-H5EA__cache_iblock_clear(H5F_t *f, H5EA_iblock_t *iblock, hbool_t destroy))
+    /* Metadata checksum */
+    UINT32ENCODE(image, metadata_chksum);
 
     /* Sanity check */
-    HDassert(iblock);
-
-    /* Reset the dirty flag */
-    iblock->cache_info.is_dirty = FALSE;
-
-    if(destroy)
-        if(H5EA__cache_iblock_dest(f, iblock) < 0)
-            H5E_THROW(H5E_CANTFREE, "unable to destroy extensible array index block")
+    HDassert((size_t)(image - (uint8_t *)_image) == len);
 
 CATCH
 
-END_FUNC(STATIC)   /* end H5EA__cache_iblock_clear() */
+END_FUNC(STATIC)   /* end H5EA__cache_iblock_serialize() */
 
 
 /*-------------------------------------------------------------------------
@@ -843,13 +801,16 @@ END_FUNC(STATIC)   /* end H5EA__cache_iblock_clear() */
  *
  * Programmer:	Quincey Koziol
  *		koziol@hdfgroup.org
- *		Mar 31 2009
+ *              July 17, 2013
  *
  *-------------------------------------------------------------------------
  */
 BEGIN_FUNC(STATIC, ERR,
 herr_t, SUCCEED, FAIL,
-H5EA__cache_iblock_notify(H5AC_notify_action_t action, H5EA_iblock_t *iblock))
+H5EA__cache_iblock_notify(H5AC_notify_action_t action, void *_thing))
+
+    /* Local variables */
+    H5EA_iblock_t *iblock = (H5EA_iblock_t *)_thing;      /* Pointer to the object */
 
     /* Sanity check */
     HDassert(iblock);
@@ -857,11 +818,16 @@ H5EA__cache_iblock_notify(H5AC_notify_action_t action, H5EA_iblock_t *iblock))
     /* Determine which action to take */
     switch(action) {
         case H5AC_NOTIFY_ACTION_AFTER_INSERT:
+        case H5AC_NOTIFY_ACTION_AFTER_LOAD:
             /* Create flush dependency on extensible array header */
             if(H5EA__create_flush_depend((H5AC_info_t *)iblock->hdr, (H5AC_info_t *)iblock) < 0)
                 H5E_THROW(H5E_CANTDEPEND, "unable to create flush dependency between index block and header, address = %llu", (unsigned long long)iblock->addr)
             break;
 
+	case H5AC_NOTIFY_ACTION_AFTER_FLUSH:
+	    /* do nothing */
+	    break;
+
         case H5AC_NOTIFY_ACTION_BEFORE_EVICT:
             /* Destroy flush dependency on extensible array header */
             if(H5EA__destroy_flush_depend((H5AC_info_t *)iblock->hdr, (H5AC_info_t *)iblock) < 0)
@@ -878,165 +844,155 @@ END_FUNC(STATIC)   /* end H5EA__cache_iblock_notify() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5EA__cache_iblock_size
+ * Function:	H5EA__cache_iblock_free_icr
  *
- * Purpose:	Compute the size in bytes of a extensible array index block
- *		on disk, and return it in *size_ptr.  On failure,
- *		the value of *size_ptr is undefined.
+ * Purpose:	Destroy/release an "in core representation" of a data
+ *              structure
  *
  * Return:	Non-negative on success/Negative on failure
  *
  * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Sept 9 2008
+ *              koziol@hdfgroup.org
+ *              July 17, 2013
  *
  *-------------------------------------------------------------------------
  */
-/* ARGSUSED */
-BEGIN_FUNC(STATIC, NOERR,
-herr_t, SUCCEED, -,
-H5EA__cache_iblock_size(const H5F_t H5_ATTR_UNUSED *f, const H5EA_iblock_t *iblock,
-    size_t *size_ptr))
+BEGIN_FUNC(STATIC, ERR,
+herr_t, SUCCEED, FAIL,
+H5EA__cache_iblock_free_icr(void *thing))
 
-    /* Sanity check */
-    HDassert(f);
-    HDassert(iblock);
-    HDassert(size_ptr);
+    /* Check arguments */
+    HDassert(thing);
+
+    /* Release the extensible array index block */
+    if(H5EA__iblock_dest((H5EA_iblock_t *)thing) < 0)
+        H5E_THROW(H5E_CANTFREE, "can't free extensible array index block")
 
-    /* Set size value */
-    *size_ptr = iblock->size;
+CATCH
 
-END_FUNC(STATIC)   /* end H5EA__cache_iblock_size() */
+END_FUNC(STATIC)   /* end H5EA__cache_iblock_free_icr() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5EA__cache_iblock_dest
+ * Function:    H5EA__cache_sblock_get_load_size
  *
- * Purpose:	Destroys an extensible array index block in memory.
+ * Purpose:     Compute the size of the data structure on disk.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Sep  9 2008
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              July 17, 2013
  *
  *-------------------------------------------------------------------------
  */
-BEGIN_FUNC(STATIC, ERR,
-herr_t, SUCCEED, FAIL,
-H5EA__cache_iblock_dest(H5F_t *f, H5EA_iblock_t *iblock))
-
-    /* Sanity check */
-    HDassert(f);
-    HDassert(iblock);
-
-    /* Verify that index block is clean */
-    HDassert(iblock->cache_info.is_dirty == FALSE);
-
-    /* If we're going to free the space on disk, the address must be valid */
-    HDassert(!iblock->cache_info.free_file_space_on_destroy || H5F_addr_defined(iblock->cache_info.addr));
+BEGIN_FUNC(STATIC, NOERR,
+herr_t, SUCCEED, -,
+H5EA__cache_sblock_get_load_size(const void *_udata, size_t *image_len))
 
-    /* Check for freeing file space for extensible array index block */
-    if(iblock->cache_info.free_file_space_on_destroy) {
-        /* Sanity check address */
-        HDassert(H5F_addr_eq(iblock->addr, iblock->cache_info.addr));
+    /* Local variables */
+    const H5EA_sblock_cache_ud_t *udata = (const H5EA_sblock_cache_ud_t *)_udata;      /* User data */
+    H5EA_sblock_t sblock;           /* Fake super block for computing size */
 
-        /* Release the space on disk */
-        /* (XXX: Nasty usage of internal DXPL value! -QAK) */
-        if(H5MF_xfree(f, H5FD_MEM_EARRAY_IBLOCK, H5AC_dxpl_id, iblock->cache_info.addr, (hsize_t)iblock->size) < 0)
-            H5E_THROW(H5E_CANTFREE, "unable to free extensible array index block")
+    /* Check arguments */
+    HDassert(udata);
+    HDassert(udata->hdr);
+    HDassert(udata->parent);
+    HDassert(udata->sblk_idx > 0);
+    HDassert(H5F_addr_defined(udata->sblk_addr));
+    HDassert(image_len);
+
+    /* Set up fake super block for computing size on disk */
+    /* (Note: extracted from H5EA__sblock_alloc) */
+    HDmemset(&sblock, 0, sizeof(sblock));
+    sblock.hdr = udata->hdr;
+    sblock.ndblks = udata->hdr->sblk_info[udata->sblk_idx].ndblks;
+    sblock.dblk_nelmts = udata->hdr->sblk_info[udata->sblk_idx].dblk_nelmts;
+
+    /* Check if # of elements in data blocks requires paging */
+    if(sblock.dblk_nelmts > udata->hdr->dblk_page_nelmts) {
+        /* Compute # of pages in each data block from this super block */
+        sblock.dblk_npages = sblock.dblk_nelmts / udata->hdr->dblk_page_nelmts;
+
+        /* Sanity check that we have at least 2 pages in data block */
+        HDassert(sblock.dblk_npages > 1);
+
+        /* Sanity check for integer truncation */
+        HDassert((sblock.dblk_npages * udata->hdr->dblk_page_nelmts) == sblock.dblk_nelmts);
+
+        /* Compute size of buffer for each data block's 'page init' bitmask */
+        sblock.dblk_page_init_size = ((sblock.dblk_npages) + 7) / 8;
+        HDassert(sblock.dblk_page_init_size > 0);
     } /* end if */
 
-    /* Release the index block */
-    if(H5EA__iblock_dest(iblock) < 0)
-        H5E_THROW(H5E_CANTFREE, "can't free extensible array index block")
-
-CATCH
+    /* Set the image length size */
+    *image_len = (size_t)H5EA_SBLOCK_SIZE(&sblock);
 
-END_FUNC(STATIC)   /* end H5EA__cache_iblock_dest() */
+END_FUNC(STATIC)   /* end H5EA__cache_sblock_get_load_size() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5EA__cache_sblock_load
+ * Function:	H5EA__cache_sblock_deserialize
  *
- * Purpose:	Loads an extensible array super block from the disk.
+ * Purpose:	Loads a data structure from the disk.
  *
- * Return:	Success:	Pointer to a new extensible array super block
+ * Return:	Success:	Pointer to a new B-tree.
  *		Failure:	NULL
  *
  * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Sep 30 2008
+ *              koziol@hdfgroup.org
+ *              July 17, 2013
  *
  *-------------------------------------------------------------------------
  */
 BEGIN_FUNC(STATIC, ERR,
-H5EA_sblock_t *, NULL, NULL,
-H5EA__cache_sblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata))
+void *, NULL, NULL,
+H5EA__cache_sblock_deserialize(const void *_image, size_t len,
+    void *_udata, hbool_t H5_ATTR_UNUSED *dirty))
 
     /* Local variables */
     H5EA_sblock_t	*sblock = NULL; /* Super block info */
-    H5EA_sblock_cache_ud_t *udata = (H5EA_sblock_cache_ud_t *)_udata;      /* User data for loading super block */
-    size_t		size;           /* Super block size */
-    H5WB_t              *wb = NULL;     /* Wrapped buffer for super block data */
-    uint8_t             sblock_buf[H5EA_IBLOCK_BUF_SIZE]; /* Buffer for super block */
-    uint8_t		*buf;           /* Pointer to super block buffer */
-    const uint8_t	*p;             /* Pointer into raw data buffer */
+    H5EA_sblock_cache_ud_t *udata = (H5EA_sblock_cache_ud_t *)_udata;      /* User data */
+    const uint8_t	*image = (const uint8_t *)_image;       /* Pointer into raw data buffer */
     uint32_t            stored_chksum;  /* Stored metadata checksum value */
     uint32_t            computed_chksum; /* Computed metadata checksum value */
     haddr_t             arr_addr;       /* Address of array header in the file */
     size_t              u;              /* Local index variable */
 
     /* Sanity check */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
-    HDassert(udata && udata->hdr && udata->parent && udata->sblk_idx > 0);
+    HDassert(udata);
+    HDassert(udata->hdr);
+    HDassert(udata->parent);
+    HDassert(udata->sblk_idx > 0);
+    HDassert(H5F_addr_defined(udata->sblk_addr));
 
     /* Allocate the extensible array super block */
     if(NULL == (sblock = H5EA__sblock_alloc(udata->hdr, udata->parent, udata->sblk_idx)))
 	H5E_THROW(H5E_CANTALLOC, "memory allocation failed for extensible array super block")
 
     /* Set the extensible array super block's address */
-    sblock->addr = addr;
-
-    /* Wrap the local buffer for serialized info */
-    if(NULL == (wb = H5WB_wrap(sblock_buf, sizeof(sblock_buf))))
-	H5E_THROW(H5E_CANTINIT, "can't wrap buffer")
-
-    /* Compute the size of the extensible array super block on disk */
-    size = H5EA_SBLOCK_SIZE(sblock);
-
-    /* Get a pointer to a buffer that's large enough for serialized info */
-    if(NULL == (buf = (uint8_t *)H5WB_actual(wb, size)))
-	H5E_THROW(H5E_CANTGET, "can't get actual buffer")
-
-    /* Read super block from disk */
-    if(H5F_block_read(f, H5FD_MEM_EARRAY_SBLOCK, addr, size, dxpl_id, buf) < 0)
-	H5E_THROW(H5E_READERROR, "can't read extensible array super block")
-
-    /* Get temporary pointer to serialized header */
-    p = buf;
+    sblock->addr = udata->sblk_addr;
 
     /* Magic number */
-    if(HDmemcmp(p, H5EA_SBLOCK_MAGIC, (size_t)H5_SIZEOF_MAGIC))
+    if(HDmemcmp(image, H5EA_SBLOCK_MAGIC, (size_t)H5_SIZEOF_MAGIC))
 	H5E_THROW(H5E_BADVALUE, "wrong extensible array super block signature")
-    p += H5_SIZEOF_MAGIC;
+    image += H5_SIZEOF_MAGIC;
 
     /* Version */
-    if(*p++ != H5EA_SBLOCK_VERSION)
+    if(*image++ != H5EA_SBLOCK_VERSION)
 	H5E_THROW(H5E_VERSION, "wrong extensible array super block version")
 
     /* Extensible array type */
-    if(*p++ != (uint8_t)udata->hdr->cparam.cls->id)
+    if(*image++ != (uint8_t)udata->hdr->cparam.cls->id)
 	H5E_THROW(H5E_BADTYPE, "incorrect extensible array class")
 
     /* Address of header for array that owns this block (just for file integrity checks) */
-    H5F_addr_decode(f, &p, &arr_addr);
+    H5F_addr_decode(udata->hdr->f, &image, &arr_addr);
     if(H5F_addr_ne(arr_addr, udata->hdr->addr))
 	H5E_THROW(H5E_BADVALUE, "wrong extensible array header address")
 
     /* Offset of block within the array's address space */
-    UINT64DECODE_VAR(p, sblock->block_off, udata->hdr->arr_off_size);
+    UINT64DECODE_VAR(image, sblock->block_off, udata->hdr->arr_off_size);
 
     /* Internal information */
 
@@ -1045,29 +1001,29 @@ H5EA__cache_sblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata))
         size_t tot_page_init_size = sblock->ndblks * sblock->dblk_page_init_size;        /* Compute total size of 'page init' buffer */
 
         /* Retrieve the 'page init' bitmasks */
-        HDmemcpy(sblock->page_init, p, tot_page_init_size);
-        p += tot_page_init_size;
+        HDmemcpy(sblock->page_init, image, tot_page_init_size);
+        image += tot_page_init_size;
     } /* end if */
 
     /* Decode data block addresses */
     for(u = 0; u < sblock->ndblks; u++)
-        H5F_addr_decode(f, &p, &sblock->dblk_addrs[u]);
+        H5F_addr_decode(udata->hdr->f, &image, &sblock->dblk_addrs[u]);
 
     /* Sanity check */
     /* (allow for checksum not decoded yet) */
-    HDassert((size_t)(p - buf) == (size - H5EA_SIZEOF_CHKSUM));
+    HDassert((size_t)(image - (const uint8_t *)_image) == (len - H5EA_SIZEOF_CHKSUM));
 
     /* Save the super block's size */
-    sblock->size = size;
+    sblock->size = len;
 
     /* Compute checksum on super block */
-    computed_chksum = H5_checksum_metadata(buf, (size_t)(p - buf), 0);
+    computed_chksum = H5_checksum_metadata(_image, (size_t)(image - (const uint8_t *)_image), 0);
 
     /* Metadata checksum */
-    UINT32DECODE(p, stored_chksum);
+    UINT32DECODE(image, stored_chksum);
 
     /* Sanity check */
-    HDassert((size_t)(p - buf) == sblock->size);
+    HDassert((size_t)(image - (const uint8_t *)_image) == sblock->size);
 
     /* Verify checksum */
     if(stored_chksum != computed_chksum)
@@ -1079,183 +1035,115 @@ H5EA__cache_sblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata))
 CATCH
 
     /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-	H5E_THROW(H5E_CLOSEERROR, "can't close wrapped buffer")
     if(!ret_value)
         if(sblock && H5EA__sblock_dest(sblock) < 0)
             H5E_THROW(H5E_CANTFREE, "unable to destroy extensible array super block")
 
-END_FUNC(STATIC)   /* end H5EA__cache_sblock_load() */
+END_FUNC(STATIC)   /* end H5EA__cache_sblock_deserialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5EA__cache_sblock_flush
+ * Function:    H5EA__cache_sblock_image_len
  *
- * Purpose:	Flushes a dirty extensible array super block to disk.
+ * Purpose:     Compute the size of the data structure on disk.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Sep 30 2008
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              July 17, 2013
  *
  *-------------------------------------------------------------------------
  */
-BEGIN_FUNC(STATIC, ERR,
-herr_t, SUCCEED, FAIL,
-H5EA__cache_sblock_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr,
-    H5EA_sblock_t *sblock, unsigned H5_ATTR_UNUSED * flags_ptr))
+BEGIN_FUNC(STATIC, NOERR,
+herr_t, SUCCEED, -,
+H5EA__cache_sblock_image_len(const void *_thing, size_t *image_len,
+    hbool_t H5_ATTR_UNUSED *compressed_ptr, size_t H5_ATTR_UNUSED *compressed_image_len_ptr))
 
     /* Local variables */
-    H5WB_t *wb = NULL;                  /* Wrapped buffer for serializing data */
-    uint8_t ser_buf[H5EA_SBLOCK_BUF_SIZE]; /* Serialization buffer */
+    const H5EA_sblock_t *sblock = (const H5EA_sblock_t *)_thing;      /* Pointer to the object */
 
-    /* Sanity check */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
+    /* Check arguments */
     HDassert(sblock);
-    HDassert(sblock->hdr);
+    HDassert(image_len);
 
-    if(sblock->cache_info.is_dirty) {
-        uint8_t	*buf;           /* Temporary raw data buffer */
-        uint8_t *p;             /* Pointer into raw data buffer */
-        size_t	size;           /* Index block size on disk */
-        uint32_t metadata_chksum; /* Computed metadata checksum value */
-        size_t u;               /* Local index variable */
+    /* Set the image length size */
+    *image_len = sblock->size;
 
-        /* Wrap the local buffer for serialized info */
-        if(NULL == (wb = H5WB_wrap(ser_buf, sizeof(ser_buf))))
-            H5E_THROW(H5E_CANTINIT, "can't wrap buffer")
-
-        /* Compute the size of the super block on disk */
-        size = sblock->size;
-
-        /* Get a pointer to a buffer that's large enough for serialized info */
-        if(NULL == (buf = (uint8_t *)H5WB_actual(wb, size)))
-            H5E_THROW(H5E_CANTGET, "can't get actual buffer")
-
-        /* Get temporary pointer to serialized info */
-        p = buf;
-
-        /* Magic number */
-        HDmemcpy(p, H5EA_SBLOCK_MAGIC, (size_t)H5_SIZEOF_MAGIC);
-        p += H5_SIZEOF_MAGIC;
-
-        /* Version # */
-        *p++ = H5EA_SBLOCK_VERSION;
-
-        /* Extensible array type */
-        *p++ = sblock->hdr->cparam.cls->id;
-
-        /* Address of array header for array which owns this block */
-        H5F_addr_encode(f, &p, sblock->hdr->addr);
-
-        /* Offset of block in array */
-        UINT64ENCODE_VAR(p, sblock->block_off, sblock->hdr->arr_off_size);
-
-        /* Internal information */
-
-        /* Check for 'page init' bitmasks for this super block */
-        if(sblock->dblk_npages > 0) {
-            size_t tot_page_init_size = sblock->ndblks * sblock->dblk_page_init_size;        /* Compute total size of 'page init' buffer */
-
-            /* Store the 'page init' bitmasks */
-            HDmemcpy(p, sblock->page_init, tot_page_init_size);
-            p += tot_page_init_size;
-        } /* end if */
-
-        /* Encode addresses of data blocks in super block */
-        for(u = 0; u < sblock->ndblks; u++)
-            H5F_addr_encode(f, &p, sblock->dblk_addrs[u]);
-
-        /* Compute metadata checksum */
-        metadata_chksum = H5_checksum_metadata(buf, (size_t)(p - buf), 0);
-
-        /* Metadata checksum */
-        UINT32ENCODE(p, metadata_chksum);
-
-	/* Write the super block */
-        HDassert((size_t)(p - buf) == size);
-	if(H5F_block_write(f, H5FD_MEM_EARRAY_SBLOCK, addr, size, dxpl_id, buf) < 0)
-            H5E_THROW(H5E_WRITEERROR, "unable to save extensible array super block to disk")
-
-	sblock->cache_info.is_dirty = FALSE;
-    } /* end if */
-
-    if(destroy)
-        if(H5EA__cache_sblock_dest(f, sblock) < 0)
-            H5E_THROW(H5E_CANTFREE, "unable to destroy extensible array super block")
-
-CATCH
-
-    /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-	H5E_THROW(H5E_CLOSEERROR, "can't close wrapped buffer")
-
-END_FUNC(STATIC)   /* end H5EA__cache_sblock_flush() */
+END_FUNC(STATIC)   /* end H5EA__cache_sblock_image_len() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5EA__cache_sblock_clear
+ * Function:	H5EA__cache_sblock_serialize
  *
- * Purpose:	Mark a extensible array super block in memory as non-dirty.
+ * Purpose:	Flushes a dirty object to disk.
  *
  * Return:	Non-negative on success/Negative on failure
  *
  * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Sept 30 2008
+ *              koziol@hdfgroup.org
+ *              July 17, 2013
  *
  *-------------------------------------------------------------------------
  */
-BEGIN_FUNC(STATIC, ERR,
-herr_t, SUCCEED, FAIL,
-H5EA__cache_sblock_clear(H5F_t *f, H5EA_sblock_t *sblock, hbool_t destroy))
+BEGIN_FUNC(STATIC, NOERR,
+herr_t, SUCCEED, -,
+H5EA__cache_sblock_serialize(const H5F_t *f, void *_image, size_t H5_ATTR_UNUSED len,
+    void *_thing))
 
-    /* Sanity check */
+    /* Local variables */
+    H5EA_sblock_t *sblock = (H5EA_sblock_t *)_thing;      /* Pointer to the object to serialize */
+    uint8_t *image = (uint8_t *)_image;         /* Pointer into raw data buffer */
+    uint32_t metadata_chksum;   /* Computed metadata checksum value */
+    size_t u;                   /* Local index variable */
+
+    /* check arguments */
+    HDassert(f);
+    HDassert(image);
     HDassert(sblock);
+    HDassert(sblock->hdr);
 
-    /* Reset the dirty flag */
-    sblock->cache_info.is_dirty = FALSE;
+    /* Magic number */
+    HDmemcpy(image, H5EA_SBLOCK_MAGIC, (size_t)H5_SIZEOF_MAGIC);
+    image += H5_SIZEOF_MAGIC;
 
-    if(destroy)
-        if(H5EA__cache_sblock_dest(f, sblock) < 0)
-            H5E_THROW(H5E_CANTFREE, "unable to destroy extensible array super block")
+    /* Version # */
+    *image++ = H5EA_SBLOCK_VERSION;
 
-CATCH
+    /* Extensible array type */
+    *image++ = sblock->hdr->cparam.cls->id;
 
-END_FUNC(STATIC)   /* end H5EA__cache_sblock_clear() */
+    /* Address of array header for array which owns this block */
+    H5F_addr_encode(f, &image, sblock->hdr->addr);
 
-
-/*-------------------------------------------------------------------------
- * Function:	H5EA__cache_sblock_size
- *
- * Purpose:	Compute the size in bytes of a extensible array super block
- *		on disk, and return it in *size_ptr.  On failure,
- *		the value of *size_ptr is undefined.
- *
- * Return:	Non-negative on success/Negative on failure
- *
- * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Sept 30 2008
- *
- *-------------------------------------------------------------------------
- */
-/* ARGSUSED */
-BEGIN_FUNC(STATIC, NOERR,
-herr_t, SUCCEED, -,
-H5EA__cache_sblock_size(const H5F_t H5_ATTR_UNUSED *f, const H5EA_sblock_t *sblock,
-    size_t *size_ptr))
+    /* Offset of block in array */
+    UINT64ENCODE_VAR(image, sblock->block_off, sblock->hdr->arr_off_size);
 
-    /* Sanity check */
-    HDassert(sblock);
-    HDassert(size_ptr);
+    /* Internal information */
+
+    /* Check for 'page init' bitmasks for this super block */
+    if(sblock->dblk_npages > 0) {
+        size_t tot_page_init_size = sblock->ndblks * sblock->dblk_page_init_size;        /* Compute total size of 'page init' buffer */
 
-    /* Set size value */
-    *size_ptr = sblock->size;
+        /* Store the 'page init' bitmasks */
+        HDmemcpy(image, sblock->page_init, tot_page_init_size);
+        image += tot_page_init_size;
+    } /* end if */
+
+    /* Encode addresses of data blocks in super block */
+    for(u = 0; u < sblock->ndblks; u++)
+        H5F_addr_encode(f, &image, sblock->dblk_addrs[u]);
+
+    /* Compute metadata checksum */
+    metadata_chksum = H5_checksum_metadata(_image, (size_t)(image - (uint8_t *)_image), 0);
+
+    /* Metadata checksum */
+    UINT32ENCODE(image, metadata_chksum);
+
+    /* Sanity check */
+    HDassert((size_t)(image - (uint8_t *)_image) == len);
 
-END_FUNC(STATIC)   /* end H5EA__cache_sblock_size() */
+END_FUNC(STATIC)   /* end H5EA__cache_sblock_serialize() */
 
 
 /*-------------------------------------------------------------------------
@@ -1273,7 +1161,10 @@ END_FUNC(STATIC)   /* end H5EA__cache_sblock_size() */
  */
 BEGIN_FUNC(STATIC, ERR,
 herr_t, SUCCEED, FAIL,
-H5EA__cache_sblock_notify(H5AC_notify_action_t action, H5EA_sblock_t *sblock))
+H5EA__cache_sblock_notify(H5AC_notify_action_t action, void *_thing))
+
+    /* Local variables */
+    H5EA_sblock_t *sblock = (H5EA_sblock_t *)_thing;      /* Pointer to the object */
 
     /* Sanity check */
     HDassert(sblock);
@@ -1281,11 +1172,16 @@ H5EA__cache_sblock_notify(H5AC_notify_action_t action, H5EA_sblock_t *sblock))
     /* Determine which action to take */
     switch(action) {
         case H5AC_NOTIFY_ACTION_AFTER_INSERT:
+        case H5AC_NOTIFY_ACTION_AFTER_LOAD:
             /* Create flush dependency on index block */
             if(H5EA__create_flush_depend((H5AC_info_t *)sblock->parent, (H5AC_info_t *)sblock) < 0)
                 H5E_THROW(H5E_CANTDEPEND, "unable to create flush dependency between super block and index block, address = %llu", (unsigned long long)sblock->addr)
             break;
 
+	case H5AC_NOTIFY_ACTION_AFTER_FLUSH:
+	    /* do nothing */
+	    break;
+
         case H5AC_NOTIFY_ACTION_BEFORE_EVICT:
             /* Destroy flush dependency on index block */
             if(H5EA__destroy_flush_depend((H5AC_info_t *)sblock->parent, (H5AC_info_t *)sblock) < 0)
@@ -1302,135 +1198,158 @@ END_FUNC(STATIC)   /* end H5EA__cache_sblock_notify() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5EA__cache_sblock_dest
+ * Function:	H5EA__cache_sblock_free_icr
  *
- * Purpose:	Destroys an extensible array super block in memory.
+ * Purpose:	Destroy/release an "in core representation" of a data
+ *              structure
  *
  * Return:	Non-negative on success/Negative on failure
  *
  * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Sep 30 2008
+ *              koziol@hdfgroup.org
+ *              July 17, 2013
  *
  *-------------------------------------------------------------------------
  */
 BEGIN_FUNC(STATIC, ERR,
 herr_t, SUCCEED, FAIL,
-H5EA__cache_sblock_dest(H5F_t *f, H5EA_sblock_t *sblock))
+H5EA__cache_sblock_free_icr(void *thing))
 
-    /* Sanity check */
-    HDassert(f);
-    HDassert(sblock);
+    /* Check arguments */
+    HDassert(thing);
 
-    /* Verify that super block is clean */
-    HDassert(sblock->cache_info.is_dirty == FALSE);
+    /* Release the extensible array super block */
+    if(H5EA__sblock_dest((H5EA_sblock_t *)thing) < 0)
+        H5E_THROW(H5E_CANTFREE, "can't free extensible array super block")
 
-    /* If we're going to free the space on disk, the address must be valid */
-    HDassert(!sblock->cache_info.free_file_space_on_destroy || H5F_addr_defined(sblock->cache_info.addr));
+CATCH
 
-    /* Check for freeing file space for extensible array super block */
-    if(sblock->cache_info.free_file_space_on_destroy) {
-        /* Sanity check address */
-        HDassert(H5F_addr_eq(sblock->addr, sblock->cache_info.addr));
+END_FUNC(STATIC)   /* end H5EA__cache_sblock_free_icr() */
 
-        /* Release the space on disk */
-        /* (XXX: Nasty usage of internal DXPL value! -QAK) */
-        if(H5MF_xfree(f, H5FD_MEM_EARRAY_SBLOCK, H5AC_dxpl_id, sblock->cache_info.addr, (hsize_t)sblock->size) < 0)
-            H5E_THROW(H5E_CANTFREE, "unable to free extensible array super block")
-    } /* end if */
+
+/*-------------------------------------------------------------------------
+ * Function:    H5EA__cache_dblock_get_load_size
+ *
+ * Purpose:     Compute the size of the data structure on disk.
+ *
+ * Return:      Non-negative on success/Negative on failure
+ *
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              July 17, 2013
+ *
+ *-------------------------------------------------------------------------
+ */
+BEGIN_FUNC(STATIC, NOERR,
+herr_t, SUCCEED, -,
+H5EA__cache_dblock_get_load_size(const void *_udata, size_t *image_len))
 
-    /* Release the super block */
-    if(H5EA__sblock_dest(sblock) < 0)
-        H5E_THROW(H5E_CANTFREE, "can't free extensible array super block")
+    /* Local variables */
+    const H5EA_dblock_cache_ud_t *udata = (const H5EA_dblock_cache_ud_t *)_udata;      /* User data */
+    H5EA_dblock_t dblock;           /* Fake data block for computing size */
 
-CATCH
+    /* Check arguments */
+    HDassert(udata);
+    HDassert(udata->hdr);
+    HDassert(udata->parent);
+    HDassert(udata->nelmts > 0);
+    HDassert(image_len);
+
+    /* Set up fake data block for computing size on disk */
+    /* (Note: extracted from H5EA__dblock_alloc) */
+    HDmemset(&dblock, 0, sizeof(dblock));
+
+    /* need to set:
+     * 
+     *    dblock.hdr
+     *    dblock.npages
+     *    dblock.nelmts
+     *
+     * before we invoke either H5EA_DBLOCK_PREFIX_SIZE() or 
+     * H5EA_DBLOCK_SIZE().
+     */
+    dblock.hdr = udata->hdr;
+    dblock.nelmts = udata->nelmts;
+
+    if(udata->nelmts > udata->hdr->dblk_page_nelmts) {
+        /* Set the # of pages in the direct block */
+        dblock.npages = udata->nelmts / udata->hdr->dblk_page_nelmts;
+        HDassert(udata->nelmts==(dblock.npages * udata->hdr->dblk_page_nelmts));
+    } /* end if */
 
-END_FUNC(STATIC)   /* end H5EA__cache_sblock_dest() */
+    /* Set the image length size */
+    if(!dblock.npages)
+        *image_len = H5EA_DBLOCK_SIZE(&dblock);
+    else
+        *image_len = H5EA_DBLOCK_PREFIX_SIZE(&dblock);
+
+END_FUNC(STATIC)   /* end H5EA__cache_dblock_get_load_size() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5EA__cache_dblock_load
+ * Function:	H5EA__cache_dblock_deserialize
  *
- * Purpose:	Loads an extensible array data block from the disk.
+ * Purpose:	Loads a data structure from the disk.
  *
- * Return:	Success:	Pointer to a new extensible array data block
+ * Return:	Success:	Pointer to a new B-tree.
  *		Failure:	NULL
  *
  * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Sep 16 2008
+ *              koziol@hdfgroup.org
+ *              July 17, 2013
  *
  *-------------------------------------------------------------------------
  */
 BEGIN_FUNC(STATIC, ERR,
-H5EA_dblock_t *, NULL, NULL,
-H5EA__cache_dblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata))
+void *, NULL, NULL,
+H5EA__cache_dblock_deserialize(const void *_image, size_t len,
+    void *_udata, hbool_t H5_ATTR_UNUSED *dirty))
 
     /* Local variables */
     H5EA_dblock_t	*dblock = NULL; /* Data block info */
-    H5EA_dblock_cache_ud_t *udata = (H5EA_dblock_cache_ud_t *)_udata;      /* User data for loading data block */
-    size_t		size;           /* Data block size */
-    H5WB_t              *wb = NULL;     /* Wrapped buffer for data block data */
-    uint8_t             dblock_buf[H5EA_DBLOCK_BUF_SIZE]; /* Buffer for data block */
-    uint8_t		*buf;           /* Pointer to data block buffer */
-    const uint8_t	*p;             /* Pointer into raw data buffer */
+    H5EA_dblock_cache_ud_t *udata = (H5EA_dblock_cache_ud_t *)_udata;      /* User data */
+    const uint8_t	*image = (const uint8_t *)_image;       /* Pointer into raw data buffer */
     uint32_t            stored_chksum;  /* Stored metadata checksum value */
     uint32_t            computed_chksum; /* Computed metadata checksum value */
     haddr_t             arr_addr;       /* Address of array header in the file */
 
-    /* Sanity check */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
-    HDassert(udata && udata->hdr && udata->parent && udata->nelmts > 0);
+    /* Check arguments */
+    HDassert(udata);
+    HDassert(udata->hdr);
+    HDassert(udata->parent);
+    HDassert(udata->nelmts > 0);
+    HDassert(H5F_addr_defined(udata->dblk_addr));
 
     /* Allocate the extensible array data block */
     if(NULL == (dblock = H5EA__dblock_alloc(udata->hdr, udata->parent, udata->nelmts)))
 	H5E_THROW(H5E_CANTALLOC, "memory allocation failed for extensible array data block")
 
-    /* Set the extensible array data block's information */
-    dblock->addr = addr;
-
-    /* Wrap the local buffer for serialized info */
-    if(NULL == (wb = H5WB_wrap(dblock_buf, sizeof(dblock_buf))))
-	H5E_THROW(H5E_CANTINIT, "can't wrap buffer")
+    HDassert(((!dblock->npages) && (len == H5EA_DBLOCK_SIZE(dblock))) || 
+             (len == H5EA_DBLOCK_PREFIX_SIZE(dblock)));
 
-    /* Compute the size of the extensible array data block on disk */
-    if(!dblock->npages)
-        size = H5EA_DBLOCK_SIZE(dblock);
-    else
-        size = H5EA_DBLOCK_PREFIX_SIZE(dblock);
-
-    /* Get a pointer to a buffer that's large enough for serialized info */
-    if(NULL == (buf = (uint8_t *)H5WB_actual(wb, size)))
-	H5E_THROW(H5E_CANTGET, "can't get actual buffer")
-
-    /* Read data block from disk */
-    if(H5F_block_read(f, H5FD_MEM_EARRAY_DBLOCK, addr, size, dxpl_id, buf) < 0)
-	H5E_THROW(H5E_READERROR, "can't read extensible array data block")
-
-    /* Get temporary pointer to serialized header */
-    p = buf;
+    /* Set the extensible array data block's information */
+    dblock->addr = udata->dblk_addr;
 
     /* Magic number */
-    if(HDmemcmp(p, H5EA_DBLOCK_MAGIC, (size_t)H5_SIZEOF_MAGIC))
+    if(HDmemcmp(image, H5EA_DBLOCK_MAGIC, (size_t)H5_SIZEOF_MAGIC))
 	H5E_THROW(H5E_BADVALUE, "wrong extensible array data block signature")
-    p += H5_SIZEOF_MAGIC;
+    image += H5_SIZEOF_MAGIC;
 
     /* Version */
-    if(*p++ != H5EA_DBLOCK_VERSION)
+    if(*image++ != H5EA_DBLOCK_VERSION)
 	H5E_THROW(H5E_VERSION, "wrong extensible array data block version")
 
     /* Extensible array type */
-    if(*p++ != (uint8_t)udata->hdr->cparam.cls->id)
+    if(*image++ != (uint8_t)udata->hdr->cparam.cls->id)
 	H5E_THROW(H5E_BADTYPE, "incorrect extensible array class")
 
     /* Address of header for array that owns this block (just for file integrity checks) */
-    H5F_addr_decode(f, &p, &arr_addr);
+    H5F_addr_decode(udata->hdr->f, &image, &arr_addr);
     if(H5F_addr_ne(arr_addr, udata->hdr->addr))
 	H5E_THROW(H5E_BADVALUE, "wrong extensible array header address")
 
     /* Offset of block within the array's address space */
-    UINT64DECODE_VAR(p, dblock->block_off, udata->hdr->arr_off_size);
+    UINT64DECODE_VAR(image, dblock->block_off, udata->hdr->arr_off_size);
 
     /* Internal information */
 
@@ -1438,26 +1357,27 @@ H5EA__cache_dblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata))
     if(!dblock->npages) {
         /* Decode elements in data block */
         /* Convert from raw elements on disk into native elements in memory */
-        if((udata->hdr->cparam.cls->decode)(p, dblock->elmts, udata->nelmts, udata->hdr->cb_ctx) < 0)
+        if((udata->hdr->cparam.cls->decode)(image, dblock->elmts, udata->nelmts, udata->hdr->cb_ctx) < 0)
             H5E_THROW(H5E_CANTDECODE, "can't decode extensible array data elements")
-        p += (udata->nelmts * udata->hdr->cparam.raw_elmt_size);
+        image += (udata->nelmts * udata->hdr->cparam.raw_elmt_size);
     } /* end if */
 
     /* Sanity check */
     /* (allow for checksum not decoded yet) */
-    HDassert((size_t)(p - buf) == (size - H5EA_SIZEOF_CHKSUM));
+    HDassert((size_t)(image - (const uint8_t *)_image) == (len - H5EA_SIZEOF_CHKSUM));
 
     /* Set the data block's size */
+    /* (Note: This is not the same as the image length, for paged data blocks) */
     dblock->size = H5EA_DBLOCK_SIZE(dblock);
 
     /* Compute checksum on data block */
-    computed_chksum = H5_checksum_metadata(buf, (size_t)(p - buf), 0);
+    computed_chksum = H5_checksum_metadata(_image, (size_t)(image - (const uint8_t *)_image), 0);
 
     /* Metadata checksum */
-    UINT32DECODE(p, stored_chksum);
+    UINT32DECODE(image, stored_chksum);
 
     /* Sanity check */
-    HDassert((size_t)(p - buf) == size);
+    HDassert((size_t)(image - (const uint8_t *)_image) == len);
 
     /* Verify checksum */
     if(stored_chksum != computed_chksum)
@@ -1469,151 +1389,116 @@ H5EA__cache_dblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata))
 CATCH
 
     /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-	H5E_THROW(H5E_CLOSEERROR, "can't close wrapped buffer")
     if(!ret_value)
         if(dblock && H5EA__dblock_dest(dblock) < 0)
             H5E_THROW(H5E_CANTFREE, "unable to destroy extensible array data block")
 
-END_FUNC(STATIC)   /* end H5EA__cache_dblock_load() */
+END_FUNC(STATIC)   /* end H5EA__cache_dblock_deserialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5EA__cache_dblock_flush
+ * Function:    H5EA__cache_dblock_image_len
  *
- * Purpose:	Flushes a dirty extensible array data block to disk.
+ * Purpose:     Compute the size of the data structure on disk.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Sep 18 2008
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              July 17, 2013
  *
  *-------------------------------------------------------------------------
  */
-BEGIN_FUNC(STATIC, ERR,
-herr_t, SUCCEED, FAIL,
-H5EA__cache_dblock_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr,
-    H5EA_dblock_t *dblock, unsigned H5_ATTR_UNUSED * flags_ptr))
+BEGIN_FUNC(STATIC, NOERR,
+herr_t, SUCCEED, -,
+H5EA__cache_dblock_image_len(const void *_thing, size_t *image_len,
+    hbool_t H5_ATTR_UNUSED *compressed_ptr, size_t H5_ATTR_UNUSED *compressed_image_len_ptr))
 
     /* Local variables */
-    H5WB_t *wb = NULL;                  /* Wrapped buffer for serializing data */
-    uint8_t ser_buf[H5EA_DBLOCK_BUF_SIZE]; /* Serialization buffer */
+    const H5EA_dblock_t *dblock = (const H5EA_dblock_t *)_thing;      /* Pointer to the object */
 
-    /* Sanity check */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
+    /* Check arguments */
     HDassert(dblock);
-    HDassert(dblock->hdr);
+    HDassert(image_len);
 
-    if(dblock->cache_info.is_dirty) {
-        uint8_t	*buf;           /* Temporary raw data buffer */
-        uint8_t *p;             /* Pointer into raw data buffer */
-        size_t	size;           /* Index block size on disk */
-        uint32_t metadata_chksum; /* Computed metadata checksum value */
-
-        /* Wrap the local buffer for serialized info */
-        if(NULL == (wb = H5WB_wrap(ser_buf, sizeof(ser_buf))))
-            H5E_THROW(H5E_CANTINIT, "can't wrap buffer")
-
-        /* Compute the size of the data block on disk */
-        if(!dblock->npages)
-            size = dblock->size;
-        else
-            size = H5EA_DBLOCK_PREFIX_SIZE(dblock);
-
-        /* Get a pointer to a buffer that's large enough for serialized info */
-        if(NULL == (buf = (uint8_t *)H5WB_actual(wb, size)))
-            H5E_THROW(H5E_CANTGET, "can't get actual buffer")
-
-        /* Get temporary pointer to serialized info */
-        p = buf;
-
-        /* Magic number */
-        HDmemcpy(p, H5EA_DBLOCK_MAGIC, (size_t)H5_SIZEOF_MAGIC);
-        p += H5_SIZEOF_MAGIC;
-
-        /* Version # */
-        *p++ = H5EA_DBLOCK_VERSION;
-
-        /* Extensible array type */
-        *p++ = dblock->hdr->cparam.cls->id;
-
-        /* Address of array header for array which owns this block */
-        H5F_addr_encode(f, &p, dblock->hdr->addr);
-
-        /* Offset of block in array */
-        UINT64ENCODE_VAR(p, dblock->block_off, dblock->hdr->arr_off_size);
-
-        /* Internal information */
-
-        /* Only encode elements if the data block is not paged */
-        if(!dblock->npages) {
-            /* Encode elements in data block */
-
-            /* Convert from native elements in memory into raw elements on disk */
-            if((dblock->hdr->cparam.cls->encode)(p, dblock->elmts, dblock->nelmts, dblock->hdr->cb_ctx) < 0)
-                H5E_THROW(H5E_CANTENCODE, "can't encode extensible array data elements")
-            p += (dblock->nelmts * dblock->hdr->cparam.raw_elmt_size);
-        } /* end if */
-
-        /* Compute metadata checksum */
-        metadata_chksum = H5_checksum_metadata(buf, (size_t)(p - buf), 0);
-
-        /* Metadata checksum */
-        UINT32ENCODE(p, metadata_chksum);
-
-	/* Write the data block */
-        HDassert((size_t)(p - buf) == size);
-	if(H5F_block_write(f, H5FD_MEM_EARRAY_DBLOCK, addr, size, dxpl_id, buf) < 0)
-            H5E_THROW(H5E_WRITEERROR, "unable to save extensible array data block to disk")
-
-	dblock->cache_info.is_dirty = FALSE;
-    } /* end if */
-
-    if(destroy)
-        if(H5EA__cache_dblock_dest(f, dblock) < 0)
-            H5E_THROW(H5E_CANTFREE, "unable to destroy extensible array data block")
-
-CATCH
-
-    /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-	H5E_THROW(H5E_CLOSEERROR, "can't close wrapped buffer")
+    /* Set the image length size */
+    if(!dblock->npages)
+        *image_len = dblock->size;
+    else
+        *image_len = (size_t)H5EA_DBLOCK_PREFIX_SIZE(dblock);
 
-END_FUNC(STATIC)   /* end H5EA__cache_dblock_flush() */
+END_FUNC(STATIC)   /* end H5EA__cache_dblock_image_len() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5EA__cache_dblock_clear
+ * Function:	H5EA__cache_dblock_serialize
  *
- * Purpose:	Mark a extensible array data block in memory as non-dirty.
+ * Purpose:	Flushes a dirty object to disk.
  *
  * Return:	Non-negative on success/Negative on failure
  *
  * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Sept 18 2008
+ *              koziol@hdfgroup.org
+ *              July 17, 2013
  *
  *-------------------------------------------------------------------------
  */
 BEGIN_FUNC(STATIC, ERR,
 herr_t, SUCCEED, FAIL,
-H5EA__cache_dblock_clear(H5F_t *f, H5EA_dblock_t *dblock, hbool_t destroy))
+H5EA__cache_dblock_serialize(const H5F_t *f, void *_image, size_t H5_ATTR_UNUSED len,
+    void *_thing))
 
-    /* Sanity check */
+    /* Local variables */
+    H5EA_dblock_t *dblock = (H5EA_dblock_t *)_thing;      /* Pointer to the object to serialize */
+    uint8_t *image = (uint8_t *)_image;         /* Pointer into raw data buffer */
+    uint32_t metadata_chksum;   /* Computed metadata checksum value */
+
+    /* check arguments */
+    HDassert(f);
+    HDassert(image);
     HDassert(dblock);
+    HDassert(dblock->hdr);
 
-    /* Reset the dirty flag */
-    dblock->cache_info.is_dirty = FALSE;
+    /* Magic number */
+    HDmemcpy(image, H5EA_DBLOCK_MAGIC, (size_t)H5_SIZEOF_MAGIC);
+    image += H5_SIZEOF_MAGIC;
 
-    if(destroy)
-        if(H5EA__cache_dblock_dest(f, dblock) < 0)
-            H5E_THROW(H5E_CANTFREE, "unable to destroy extensible array data block")
+    /* Version # */
+    *image++ = H5EA_DBLOCK_VERSION;
+
+    /* Extensible array type */
+    *image++ = dblock->hdr->cparam.cls->id;
+
+    /* Address of array header for array which owns this block */
+    H5F_addr_encode(f, &image, dblock->hdr->addr);
+
+    /* Offset of block in array */
+    UINT64ENCODE_VAR(image, dblock->block_off, dblock->hdr->arr_off_size);
+
+    /* Internal information */
+
+    /* Only encode elements if the data block is not paged */
+    if(!dblock->npages) {
+        /* Encode elements in data block */
+
+        /* Convert from native elements in memory into raw elements on disk */
+        if((dblock->hdr->cparam.cls->encode)(image, dblock->elmts, dblock->nelmts, dblock->hdr->cb_ctx) < 0)
+            H5E_THROW(H5E_CANTENCODE, "can't encode extensible array data elements")
+        image += (dblock->nelmts * dblock->hdr->cparam.raw_elmt_size);
+    } /* end if */
+
+    /* Compute metadata checksum */
+    metadata_chksum = H5_checksum_metadata(_image, (size_t)(image - (uint8_t *)_image), 0);
+
+    /* Metadata checksum */
+    UINT32ENCODE(image, metadata_chksum);
+
+    /* Sanity check */
+    HDassert((size_t)(image - (uint8_t *)_image) == len);
 
 CATCH
 
-END_FUNC(STATIC)   /* end H5EA__cache_dblock_clear() */
+END_FUNC(STATIC)   /* end H5EA__cache_dblock_serialize() */
 
 
 /*-------------------------------------------------------------------------
@@ -1631,19 +1516,27 @@ END_FUNC(STATIC)   /* end H5EA__cache_dblock_clear() */
  */
 BEGIN_FUNC(STATIC, ERR,
 herr_t, SUCCEED, FAIL,
-H5EA__cache_dblock_notify(H5AC_notify_action_t action, H5EA_dblock_t *dblock))
+H5EA__cache_dblock_notify(H5AC_notify_action_t action, void *_thing))
 
-    /* Sanity check */
+    /* Local variables */
+    H5EA_dblock_t *dblock = (H5EA_dblock_t *)_thing;      /* Pointer to the object */
+
+    /* Check arguments */
     HDassert(dblock);
 
     /* Determine which action to take */
     switch(action) {
         case H5AC_NOTIFY_ACTION_AFTER_INSERT:
+        case H5AC_NOTIFY_ACTION_AFTER_LOAD:
             /* Create flush dependency on parent */
             if(H5EA__create_flush_depend((H5AC_info_t *)dblock->parent, (H5AC_info_t *)dblock) < 0)
                 H5E_THROW(H5E_CANTDEPEND, "unable to create flush dependency between data block and parent, address = %llu", (unsigned long long)dblock->addr)
             break;
 
+	case H5AC_NOTIFY_ACTION_AFTER_FLUSH:
+	    /* do nothing */
+	    break;
+
         case H5AC_NOTIFY_ACTION_BEFORE_EVICT:
             /* Destroy flush dependency on parent */
             if(H5EA__destroy_flush_depend((H5AC_info_t *)dblock->parent, (H5AC_info_t *)dblock) < 0)
@@ -1660,171 +1553,175 @@ END_FUNC(STATIC)   /* end H5EA__cache_dblock_notify() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5EA__cache_dblock_size
+ * Function:	H5EA__cache_dblock_free_icr
  *
- * Purpose:	Compute the size in bytes of a extensible array data block
- *		on disk, and return it in *size_ptr.  On failure,
- *		the value of *size_ptr is undefined.
+ * Purpose:	Destroy/release an "in core representation" of a data
+ *              structure
  *
  * Return:	Non-negative on success/Negative on failure
  *
  * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Sept 18 2008
+ *              koziol@hdfgroup.org
+ *              July 17, 2013
  *
  *-------------------------------------------------------------------------
  */
-/* ARGSUSED */
-BEGIN_FUNC(STATIC, NOERR,
-herr_t, SUCCEED, -,
-H5EA__cache_dblock_size(const H5F_t H5_ATTR_UNUSED *f, const H5EA_dblock_t *dblock,
-    size_t *size_ptr))
+BEGIN_FUNC(STATIC, ERR,
+herr_t, SUCCEED, FAIL,
+H5EA__cache_dblock_free_icr(void *thing))
 
-    /* Sanity check */
-    HDassert(f);
-    HDassert(dblock);
-    HDassert(size_ptr);
+    /* Check arguments */
+    HDassert(thing);
 
-    /* Set size value */
-    if(!dblock->npages)
-        *size_ptr = dblock->size;
-    else
-        *size_ptr = H5EA_DBLOCK_PREFIX_SIZE(dblock);
+    /* Release the extensible array data block */
+    if(H5EA__dblock_dest((H5EA_dblock_t *)thing) < 0)
+        H5E_THROW(H5E_CANTFREE, "can't free extensible array data block")
+
+CATCH
 
-END_FUNC(STATIC)   /* end H5EA__cache_dblock_size() */
+END_FUNC(STATIC)   /* end H5EA__cache_dblock_free_icr() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5EA__cache_dblock_dest
+ * Function:    H5EA__cache_dblock_fsf_size
  *
- * Purpose:	Destroys an extensible array data block in memory.
+ * Purpose:     Tell the metadata cache the actual amount of file space
+ *              to free when a dblock entry is destroyed with the free
+ *              file space block set.
  *
- * Return:	Non-negative on success/Negative on failure
+ *              This function is needed when the data block is paged, as
+ *              the datablock header and all its pages are allocted as a
+ *              single contiguous chunk of file space, and must be
+ *              deallocated the same way.
  *
- * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Sep 18 2008
+ *              The size of the chunk of memory in which the dblock
+ *              header and all its pages is stored in the size field,
+ *              so we simply pass that value back to the cache.
+ *
+ *              If the datablock is not paged, then the size field of
+ *              the cache_info contains the correct size.  However this
+ *              value will be the same as the size field, so we return
+ *              the contents of the size field to the cache in this case
+ *              as well.
+ *
+ * Return:      Non-negative on success/Negative on failure
+ *
+ * Programmer:  John Mainzer
+ *              12/5/14
  *
  *-------------------------------------------------------------------------
  */
-/* ARGSUSED */
-BEGIN_FUNC(STATIC, ERR,
-herr_t, SUCCEED, FAIL,
-H5EA__cache_dblock_dest(H5F_t *f, H5EA_dblock_t *dblock))
+BEGIN_FUNC(STATIC, NOERR,
+herr_t, SUCCEED, -,
+H5EA__cache_dblock_fsf_size(const void *_thing, size_t *fsf_size))
 
-    /* Sanity check */
-    HDassert(f);
+    /* Local variables */
+    const H5EA_dblock_t *dblock = (const H5EA_dblock_t *)_thing;        /* Pointer to the object */
+
+    /* Check arguments */
     HDassert(dblock);
+    HDassert(dblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(dblock->cache_info.type == H5AC_EARRAY_DBLOCK);
+    HDassert(fsf_size);
 
-    /* Verify that data block is clean */
-    HDassert(dblock->cache_info.is_dirty == FALSE);
+    *fsf_size = dblock->size;
 
-    /* If we're going to free the space on disk, the address must be valid */
-    HDassert(!dblock->cache_info.free_file_space_on_destroy || H5F_addr_defined(dblock->cache_info.addr));
+END_FUNC(STATIC)   /* end H5EA__cache_dblock_fsf_size() */
 
-    /* Check for freeing file space for extensible array data block */
-    if(dblock->cache_info.free_file_space_on_destroy) {
-        /* Sanity check address */
-        HDassert(H5F_addr_eq(dblock->addr, dblock->cache_info.addr));
+
+/*-------------------------------------------------------------------------
+ * Function:    H5EA__cache_dblk_page_get_load_size
+ *
+ * Purpose:     Compute the size of the data structure on disk.
+ *
+ * Return:      Non-negative on success/Negative on failure
+ *
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              July 17, 2013
+ *
+ *-------------------------------------------------------------------------
+ */
+BEGIN_FUNC(STATIC, NOERR,
+herr_t, SUCCEED, -,
+H5EA__cache_dblk_page_get_load_size(const void *_udata, size_t *image_len))
 
-        /* Release the space on disk */
-        /* (Includes space for pages!) */
-        /* (XXX: Nasty usage of internal DXPL value! -QAK) */
-        if(H5MF_xfree(f, H5FD_MEM_EARRAY_DBLOCK, H5AC_dxpl_id, dblock->cache_info.addr, (hsize_t)dblock->size) < 0)
-            H5E_THROW(H5E_CANTFREE, "unable to free extensible array data block")
-    } /* end if */
+    /* Local variables */
+    const H5EA_dblk_page_cache_ud_t *udata = (const H5EA_dblk_page_cache_ud_t *)_udata;      /* User data */
 
-    /* Release the data block */
-    if(H5EA__dblock_dest(dblock) < 0)
-        H5E_THROW(H5E_CANTFREE, "can't free extensible array data block")
+    /* Check arguments */
+    HDassert(udata);
+    HDassert(udata->hdr);
+    HDassert(udata->parent);
+    HDassert(image_len);
 
-CATCH
+    *image_len = (size_t)H5EA_DBLK_PAGE_SIZE(udata->hdr);
 
-END_FUNC(STATIC)   /* end H5EA__cache_dblock_dest() */
+END_FUNC(STATIC)   /* end H5EA__cache_dblk_page_get_load_size() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5EA__cache_dblk_page_load
+ * Function:	H5EA__cache_dblk_page_deserialize
  *
- * Purpose:	Loads an extensible array data block page from the disk.
+ * Purpose:	Loads a data structure from the disk.
  *
- * Return:	Success:	Pointer to a new extensible array data block page
+ * Return:	Success:	Pointer to a new B-tree.
  *		Failure:	NULL
  *
  * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Nov 20 2008
+ *              koziol@hdfgroup.org
+ *              July 17, 2013
  *
  *-------------------------------------------------------------------------
  */
 BEGIN_FUNC(STATIC, ERR,
-H5EA_dblk_page_t *, NULL, NULL,
-H5EA__cache_dblk_page_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata))
+void *, NULL, NULL,
+H5EA__cache_dblk_page_deserialize(const void *_image, size_t len,
+    void *_udata, hbool_t H5_ATTR_UNUSED *dirty))
 
     /* Local variables */
     H5EA_dblk_page_t	*dblk_page = NULL; /* Data block page info */
     H5EA_dblk_page_cache_ud_t *udata = (H5EA_dblk_page_cache_ud_t *)_udata;      /* User data for loading data block page */
-    size_t		size;           /* Data block page size */
-    H5WB_t              *wb = NULL;     /* Wrapped buffer for data block page data */
-    uint8_t             dblk_page_buf[H5EA_DBLK_PAGE_BUF_SIZE]; /* Buffer for data block page */
-    uint8_t		*buf;           /* Pointer to data block page buffer */
-    const uint8_t	*p;             /* Pointer into raw data buffer */
+    const uint8_t	*image = (const uint8_t *)_image;       /* Pointer into raw data buffer */
     uint32_t            stored_chksum;  /* Stored metadata checksum value */
     uint32_t            computed_chksum; /* Computed metadata checksum value */
 
     /* Sanity check */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
-    HDassert(udata && udata->hdr && udata->parent);
+    HDassert(udata);
+    HDassert(udata->hdr);
+    HDassert(udata->parent);
+    HDassert(H5F_addr_defined(udata->dblk_page_addr));
 
     /* Allocate the extensible array data block page */
     if(NULL == (dblk_page = H5EA__dblk_page_alloc(udata->hdr, udata->parent)))
 	H5E_THROW(H5E_CANTALLOC, "memory allocation failed for extensible array data block page")
 
-    /* Set the extensible array data block's information */
-    dblk_page->addr = addr;
-
-    /* Wrap the local buffer for serialized info */
-    if(NULL == (wb = H5WB_wrap(dblk_page_buf, sizeof(dblk_page_buf))))
-	H5E_THROW(H5E_CANTINIT, "can't wrap buffer")
-
-    /* Compute the size of the extensible array data block page on disk */
-    size = H5EA_DBLK_PAGE_SIZE(udata->hdr);
-
-    /* Get a pointer to a buffer that's large enough for serialized info */
-    if(NULL == (buf = (uint8_t *)H5WB_actual(wb, size)))
-	H5E_THROW(H5E_CANTGET, "can't get actual buffer")
-
-    /* Read data block page from disk */
-    if(H5F_block_read(f, H5FD_MEM_EARRAY_DBLK_PAGE, addr, size, dxpl_id, buf) < 0)
-	H5E_THROW(H5E_READERROR, "can't read extensible array data block page")
-
-    /* Get temporary pointer to serialized header */
-    p = buf;
+    /* Set the extensible array data block page's information */
+    dblk_page->addr = udata->dblk_page_addr;
 
     /* Internal information */
 
     /* Decode elements in data block page */
     /* Convert from raw elements on disk into native elements in memory */
-    if((udata->hdr->cparam.cls->decode)(p, dblk_page->elmts, udata->hdr->dblk_page_nelmts, udata->hdr->cb_ctx) < 0)
+    if((udata->hdr->cparam.cls->decode)(image, dblk_page->elmts, udata->hdr->dblk_page_nelmts, udata->hdr->cb_ctx) < 0)
         H5E_THROW(H5E_CANTDECODE, "can't decode extensible array data elements")
-    p += (udata->hdr->dblk_page_nelmts * udata->hdr->cparam.raw_elmt_size);
+    image += (udata->hdr->dblk_page_nelmts * udata->hdr->cparam.raw_elmt_size);
 
     /* Sanity check */
     /* (allow for checksum not decoded yet) */
-    HDassert((size_t)(p - buf) == (size - H5EA_SIZEOF_CHKSUM));
+    HDassert((size_t)(image - (const uint8_t *)_image) == (len - H5EA_SIZEOF_CHKSUM));
 
     /* Set the data block page's size */
-    dblk_page->size = size;
+    dblk_page->size = len;
 
-    /* Compute checksum on data block */
-    computed_chksum = H5_checksum_metadata(buf, (size_t)(p - buf), 0);
+    /* Compute checksum on data block page */
+    computed_chksum = H5_checksum_metadata(_image, (size_t)(image - (const uint8_t *)_image), 0);
 
     /* Metadata checksum */
-    UINT32DECODE(p, stored_chksum);
+    UINT32DECODE(image, stored_chksum);
 
     /* Sanity check */
-    HDassert((size_t)(p - buf) == dblk_page->size);
+    HDassert((size_t)(image - (const uint8_t *)_image) == dblk_page->size);
 
     /* Verify checksum */
     if(stored_chksum != computed_chksum)
@@ -1836,129 +1733,94 @@ H5EA__cache_dblk_page_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata))
 CATCH
 
     /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-	H5E_THROW(H5E_CLOSEERROR, "can't close wrapped buffer")
     if(!ret_value)
         if(dblk_page && H5EA__dblk_page_dest(dblk_page) < 0)
             H5E_THROW(H5E_CANTFREE, "unable to destroy extensible array data block page")
 
-END_FUNC(STATIC)   /* end H5EA__cache_dblk_page_load() */
+END_FUNC(STATIC)   /* end H5EA__cache_dblk_page_deserialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5EA__cache_dblk_page_flush
+ * Function:    H5EA__cache_dblk_page_image_len
  *
- * Purpose:	Flushes a dirty extensible array data block page to disk.
+ * Purpose:     Compute the size of the data structure on disk.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Nov 20 2008
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              July 17, 2013
  *
  *-------------------------------------------------------------------------
  */
-BEGIN_FUNC(STATIC, ERR,
-herr_t, SUCCEED, FAIL,
-H5EA__cache_dblk_page_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr,
-    H5EA_dblk_page_t *dblk_page, unsigned H5_ATTR_UNUSED * flags_ptr))
+BEGIN_FUNC(STATIC, NOERR,
+herr_t, SUCCEED, -,
+H5EA__cache_dblk_page_image_len(const void *_thing, size_t *image_len,
+    hbool_t H5_ATTR_UNUSED *compressed_ptr, size_t H5_ATTR_UNUSED *compressed_image_len_ptr))
 
     /* Local variables */
-    H5WB_t *wb = NULL;                  /* Wrapped buffer for serializing data */
-    uint8_t ser_buf[H5EA_DBLK_PAGE_BUF_SIZE]; /* Serialization buffer */
+    const H5EA_dblk_page_t *dblk_page = (const H5EA_dblk_page_t *)_thing;      /* Pointer to the object */
 
-    /* Sanity check */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
+    /* Check arguments */
     HDassert(dblk_page);
-    HDassert(dblk_page->hdr);
-
-    if(dblk_page->cache_info.is_dirty) {
-        uint8_t	*buf;           /* Temporary raw data buffer */
-        uint8_t *p;             /* Pointer into raw data buffer */
-        size_t	size;           /* Index block size on disk */
-        uint32_t metadata_chksum; /* Computed metadata checksum value */
-
-        /* Wrap the local buffer for serialized info */
-        if(NULL == (wb = H5WB_wrap(ser_buf, sizeof(ser_buf))))
-            H5E_THROW(H5E_CANTINIT, "can't wrap buffer")
-
-        /* Compute the size of the data block on disk */
-        size = dblk_page->size;
-
-        /* Get a pointer to a buffer that's large enough for serialized info */
-        if(NULL == (buf = (uint8_t *)H5WB_actual(wb, size)))
-            H5E_THROW(H5E_CANTGET, "can't get actual buffer")
-
-        /* Get temporary pointer to serialized info */
-        p = buf;
-
-        /* Internal information */
-
-        /* Encode elements in data block page */
-
-        /* Convert from native elements in memory into raw elements on disk */
-        if((dblk_page->hdr->cparam.cls->encode)(p, dblk_page->elmts, dblk_page->hdr->dblk_page_nelmts, dblk_page->hdr->cb_ctx) < 0)
-            H5E_THROW(H5E_CANTENCODE, "can't encode extensible array data elements")
-        p += (dblk_page->hdr->dblk_page_nelmts * dblk_page->hdr->cparam.raw_elmt_size);
-
-        /* Compute metadata checksum */
-        metadata_chksum = H5_checksum_metadata(buf, (size_t)(p - buf), 0);
-
-        /* Metadata checksum */
-        UINT32ENCODE(p, metadata_chksum);
-
-	/* Write the data block */
-        HDassert((size_t)(p - buf) == size);
-	if(H5F_block_write(f, H5FD_MEM_EARRAY_DBLK_PAGE, addr, size, dxpl_id, buf) < 0)
-            H5E_THROW(H5E_WRITEERROR, "unable to save extensible array data block page to disk")
-
-	dblk_page->cache_info.is_dirty = FALSE;
-    } /* end if */
+    HDassert(image_len);
 
-    if(destroy)
-        if(H5EA__cache_dblk_page_dest(f, dblk_page) < 0)
-            H5E_THROW(H5E_CANTFREE, "unable to destroy extensible array data block page")
-
-CATCH
-
-    /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-	H5E_THROW(H5E_CLOSEERROR, "can't close wrapped buffer")
+    /* Set the image length size */
+    *image_len = dblk_page->size;
 
-END_FUNC(STATIC)   /* end H5EA__cache_dblk_page_flush() */
+END_FUNC(STATIC)   /* end H5EA__cache_dblk_page_image_len() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5EA__cache_dblk_page_clear
+ * Function:	H5EA__cache_dblk_page_serialize
  *
- * Purpose:	Mark a extensible array data block page in memory as non-dirty.
+ * Purpose:	Flushes a dirty object to disk.
  *
  * Return:	Non-negative on success/Negative on failure
  *
  * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Nov 20 2008
+ *              koziol@hdfgroup.org
+ *              July 17, 2013
  *
  *-------------------------------------------------------------------------
  */
 BEGIN_FUNC(STATIC, ERR,
 herr_t, SUCCEED, FAIL,
-H5EA__cache_dblk_page_clear(H5F_t *f, H5EA_dblk_page_t *dblk_page, hbool_t destroy))
+H5EA__cache_dblk_page_serialize(const H5F_t *f, void *_image, size_t H5_ATTR_UNUSED len,
+    void *_thing))
 
-    /* Sanity check */
+    /* Local variables */
+    H5EA_dblk_page_t *dblk_page = (H5EA_dblk_page_t *)_thing;      /* Pointer to the object to serialize */
+    uint8_t *image = (uint8_t *)_image;         /* Pointer into raw data buffer */
+    uint32_t metadata_chksum;   /* Computed metadata checksum value */
+
+    /* Check arguments */
+    HDassert(f);
+    HDassert(image);
     HDassert(dblk_page);
+    HDassert(dblk_page->hdr);
+
+    /* Internal information */
 
-    /* Reset the dirty flag */
-    dblk_page->cache_info.is_dirty = FALSE;
+    /* Encode elements in data block page */
 
-    if(destroy)
-        if(H5EA__cache_dblk_page_dest(f, dblk_page) < 0)
-            H5E_THROW(H5E_CANTFREE, "unable to destroy extensible array data block page")
+    /* Convert from native elements in memory into raw elements on disk */
+    if((dblk_page->hdr->cparam.cls->encode)(image, dblk_page->elmts, dblk_page->hdr->dblk_page_nelmts, dblk_page->hdr->cb_ctx) < 0)
+        H5E_THROW(H5E_CANTENCODE, "can't encode extensible array data elements")
+    image += (dblk_page->hdr->dblk_page_nelmts * dblk_page->hdr->cparam.raw_elmt_size);
+
+    /* Compute metadata checksum */
+    metadata_chksum = H5_checksum_metadata(_image, (size_t)(image - (uint8_t *)_image), 0);
+
+    /* Metadata checksum */
+    UINT32ENCODE(image, metadata_chksum);
+
+    /* Sanity check */
+    HDassert((size_t)(image - (uint8_t *)_image) == len);
 
 CATCH
 
-END_FUNC(STATIC)   /* end H5EA__cache_dblk_page_clear() */
+END_FUNC(STATIC)   /* end H5EA__cache_dblk_page_serialize() */
 
 
 /*-------------------------------------------------------------------------
@@ -1976,7 +1838,10 @@ END_FUNC(STATIC)   /* end H5EA__cache_dblk_page_clear() */
  */
 BEGIN_FUNC(STATIC, ERR,
 herr_t, SUCCEED, FAIL,
-H5EA__cache_dblk_page_notify(H5AC_notify_action_t action, H5EA_dblk_page_t *dblk_page))
+H5EA__cache_dblk_page_notify(H5AC_notify_action_t action, void *_thing))
+
+    /* Local variables */
+    H5EA_dblk_page_t *dblk_page = (H5EA_dblk_page_t *)_thing;      /* Pointer to the object */
 
     /* Sanity check */
     HDassert(dblk_page);
@@ -1984,11 +1849,16 @@ H5EA__cache_dblk_page_notify(H5AC_notify_action_t action, H5EA_dblk_page_t *dblk
     /* Determine which action to take */
     switch(action) {
         case H5AC_NOTIFY_ACTION_AFTER_INSERT:
+        case H5AC_NOTIFY_ACTION_AFTER_LOAD:
             /* Create flush dependency on parent */
             if(H5EA__create_flush_depend((H5AC_info_t *)dblk_page->parent, (H5AC_info_t *)dblk_page) < 0)
                 H5E_THROW(H5E_CANTDEPEND, "unable to create flush dependency between data block page and parent, address = %llu", (unsigned long long)dblk_page->addr)
             break;
 
+	case H5AC_NOTIFY_ACTION_AFTER_FLUSH:
+	    /* do nothing */
+	    break;
+
         case H5AC_NOTIFY_ACTION_BEFORE_EVICT:
             /* Destroy flush dependency on parent */
             if(H5EA__destroy_flush_depend((H5AC_info_t *)dblk_page->parent, (H5AC_info_t *)dblk_page) < 0)
@@ -2005,70 +1875,31 @@ END_FUNC(STATIC)   /* end H5EA__cache_dblk_page_notify() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5EA__cache_dblk_page_size
+ * Function:	H5EA__cache_dblk_page_free_icr
  *
- * Purpose:	Compute the size in bytes of a extensible array data block page
- *		on disk, and return it in *size_ptr.  On failure,
- *		the value of *size_ptr is undefined.
+ * Purpose:	Destroy/release an "in core representation" of a data
+ *              structure
  *
  * Return:	Non-negative on success/Negative on failure
  *
  * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Nov 20 2008
+ *              koziol@hdfgroup.org
+ *              July 17, 2013
  *
  *-------------------------------------------------------------------------
  */
-/* ARGSUSED */
-BEGIN_FUNC(STATIC, NOERR,
-herr_t, SUCCEED, -,
-H5EA__cache_dblk_page_size(const H5F_t H5_ATTR_UNUSED *f, const H5EA_dblk_page_t *dblk_page,
-    size_t *size_ptr))
-
-    /* Sanity check */
-    HDassert(f);
-    HDassert(dblk_page);
-    HDassert(size_ptr);
-
-    /* Set size value */
-    *size_ptr = dblk_page->size;
-
-END_FUNC(STATIC)   /* end H5EA__cache_dblk_page_size() */
-
-
-/*-------------------------------------------------------------------------
- * Function:	H5EA__cache_dblk_page_dest
- *
- * Purpose:	Destroys an extensible array data block page in memory.
- *
- * Note:	Does _not_ free the space for the page on disk, that is
- *              handled through the data block that "owns" the page.
- *
- * Return:	Non-negative on success/Negative on failure
- *
- * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Nov 20 2008
- *
- *-------------------------------------------------------------------------
- */
-/* ARGSUSED */
 BEGIN_FUNC(STATIC, ERR,
 herr_t, SUCCEED, FAIL,
-H5EA__cache_dblk_page_dest(H5F_t H5_ATTR_UNUSED *f, H5EA_dblk_page_t *dblk_page))
-
-    /* Sanity check */
-    HDassert(f);
-    HDassert(dblk_page);
+H5EA__cache_dblk_page_free_icr(void *thing))
 
-    /* Verify that data block page is clean */
-    HDassert(dblk_page->cache_info.is_dirty == FALSE);
+    /* Check arguments */
+    HDassert(thing);
 
-    /* Release the data block page */
-    if(H5EA__dblk_page_dest(dblk_page) < 0)
+    /* Release the extensible array data block page */
+    if(H5EA__dblk_page_dest((H5EA_dblk_page_t *)thing) < 0)
         H5E_THROW(H5E_CANTFREE, "can't free extensible array data block page")
 
 CATCH
 
-END_FUNC(STATIC)   /* end H5EA__cache_dblk_page_dest() */
+END_FUNC(STATIC)   /* end H5EA__cache_dblk_page_free_icr() */
 
diff --git a/src/H5EAdbg.c b/src/H5EAdbg.c
index ff55722..9c3ce6d 100644
--- a/src/H5EAdbg.c
+++ b/src/H5EAdbg.c
@@ -119,7 +119,7 @@ H5EA__hdr_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE *stream, int indent,
     } /* end if */
 
     /* Load the extensible array header */
-    if(NULL == (hdr = H5EA__hdr_protect(f, dxpl_id, addr, dbg_ctx, H5AC_READ)))
+    if(NULL == (hdr = H5EA__hdr_protect(f, dxpl_id, addr, dbg_ctx, H5AC__READ_ONLY_FLAG)))
 	H5E_THROW(H5E_CANTPROTECT, "unable to load extensible array header")
 
     /* Print opening message */
@@ -218,14 +218,14 @@ H5EA__iblock_debug(H5F_t *f, hid_t dxpl_id, haddr_t H5_ATTR_UNUSED addr, FILE *s
     } /* end if */
 
     /* Load the extensible array header */
-    if(NULL == (hdr = H5EA__hdr_protect(f, dxpl_id, hdr_addr, dbg_ctx, H5AC_READ)))
+    if(NULL == (hdr = H5EA__hdr_protect(f, dxpl_id, hdr_addr, dbg_ctx, H5AC__READ_ONLY_FLAG)))
 	H5E_THROW(H5E_CANTPROTECT, "unable to load extensible array header")
 
     /* Sanity check */
     HDassert(H5F_addr_eq(hdr->idx_blk_addr, addr));
 
     /* Protect index block */
-    if(NULL == (iblock = H5EA__iblock_protect(hdr, dxpl_id, H5AC_READ)))
+    if(NULL == (iblock = H5EA__iblock_protect(hdr, dxpl_id, H5AC__READ_ONLY_FLAG)))
         H5E_THROW(H5E_CANTPROTECT, "unable to protect extensible array index block, address = %llu", (unsigned long long)hdr->idx_blk_addr)
 
     /* Print opening message */
@@ -343,12 +343,12 @@ H5EA__sblock_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE *stream, int inde
     } /* end if */
 
     /* Load the extensible array header */
-    if(NULL == (hdr = H5EA__hdr_protect(f, dxpl_id, hdr_addr, dbg_ctx, H5AC_READ)))
+    if(NULL == (hdr = H5EA__hdr_protect(f, dxpl_id, hdr_addr, dbg_ctx, H5AC__READ_ONLY_FLAG)))
 	H5E_THROW(H5E_CANTPROTECT, "unable to load extensible array header")
 
     /* Protect super block */
     /* (Note: setting parent of super block to 'hdr' for this operation should be OK -QAK) */
-    if(NULL == (sblock = H5EA__sblock_protect(hdr, dxpl_id, (H5EA_iblock_t *)hdr, addr, sblk_idx, H5AC_READ)))
+    if(NULL == (sblock = H5EA__sblock_protect(hdr, dxpl_id, (H5EA_iblock_t *)hdr, addr, sblk_idx, H5AC__READ_ONLY_FLAG)))
         H5E_THROW(H5E_CANTPROTECT, "unable to protect extensible array super block, address = %llu", (unsigned long long)addr)
 
     /* Print opening message */
@@ -437,12 +437,12 @@ H5EA__dblock_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE *stream, int inde
     } /* end if */
 
     /* Load the extensible array header */
-    if(NULL == (hdr = H5EA__hdr_protect(f, dxpl_id, hdr_addr, dbg_ctx, H5AC_READ)))
+    if(NULL == (hdr = H5EA__hdr_protect(f, dxpl_id, hdr_addr, dbg_ctx, H5AC__READ_ONLY_FLAG)))
 	H5E_THROW(H5E_CANTPROTECT, "unable to load extensible array header")
 
     /* Protect data block */
     /* (Note: setting parent of data block to 'hdr' for this operation should be OK -QAK) */
-    if(NULL == (dblock = H5EA__dblock_protect(hdr, dxpl_id, hdr, addr, dblk_nelmts, H5AC_READ)))
+    if(NULL == (dblock = H5EA__dblock_protect(hdr, dxpl_id, hdr, addr, dblk_nelmts, H5AC__READ_ONLY_FLAG)))
         H5E_THROW(H5E_CANTPROTECT, "unable to protect extensible array data block, address = %llu", (unsigned long long)addr)
 
     /* Print opening message */
diff --git a/src/H5EAdblkpage.c b/src/H5EAdblkpage.c
index 37fd68b..5d188c2 100644
--- a/src/H5EAdblkpage.c
+++ b/src/H5EAdblkpage.c
@@ -210,7 +210,7 @@ END_FUNC(PKG)   /* end H5EA__dblk_page_create() */
 BEGIN_FUNC(PKG, ERR,
 H5EA_dblk_page_t *, NULL, NULL,
 H5EA__dblk_page_protect(H5EA_hdr_t *hdr, hid_t dxpl_id, H5EA_sblock_t *parent,
-    haddr_t dblk_page_addr, H5AC_protect_t rw))
+    haddr_t dblk_page_addr, unsigned flags))
 
     /* Local variables */
     H5EA_dblk_page_cache_ud_t udata;      /* Information needed for loading data block page */
@@ -223,12 +223,16 @@ HDfprintf(stderr, "%s: Called\n", FUNC);
     HDassert(hdr);
     HDassert(H5F_addr_defined(dblk_page_addr));
 
+    /* only the H5AC__READ_ONLY_FLAG may be set */
+    HDassert((flags & (unsigned)(~H5AC__READ_ONLY_FLAG)) == 0);
+
     /* Set up user data */
     udata.hdr = hdr;
     udata.parent = parent;
+    udata.dblk_page_addr = dblk_page_addr;
 
     /* Protect the data block page */
-    if(NULL == (ret_value = (H5EA_dblk_page_t *)H5AC_protect(hdr->f, dxpl_id, H5AC_EARRAY_DBLK_PAGE, dblk_page_addr, &udata, rw)))
+    if(NULL == (ret_value = (H5EA_dblk_page_t *)H5AC_protect(hdr->f, dxpl_id, H5AC_EARRAY_DBLK_PAGE, dblk_page_addr, &udata, flags)))
         H5E_THROW(H5E_CANTPROTECT, "unable to protect extensible array data block page, address = %llu", (unsigned long long)dblk_page_addr)
 
 CATCH
diff --git a/src/H5EAdblock.c b/src/H5EAdblock.c
index dd1e7b0..24be87a 100644
--- a/src/H5EAdblock.c
+++ b/src/H5EAdblock.c
@@ -304,7 +304,7 @@ END_FUNC(PKG)   /* end H5EA__dblock_sblk_idx() */
 BEGIN_FUNC(PKG, ERR,
 H5EA_dblock_t *, NULL, NULL,
 H5EA__dblock_protect(H5EA_hdr_t *hdr, hid_t dxpl_id, void *parent,
-    haddr_t dblk_addr, size_t dblk_nelmts, H5AC_protect_t rw))
+    haddr_t dblk_addr, size_t dblk_nelmts, unsigned flags))
 
     /* Local variables */
     H5EA_dblock_cache_ud_t udata;      /* Information needed for loading data block */
@@ -318,13 +318,17 @@ HDfprintf(stderr, "%s: Called\n", FUNC);
     HDassert(H5F_addr_defined(dblk_addr));
     HDassert(dblk_nelmts);
 
+    /* only the H5AC__READ_ONLY_FLAG may be set */
+    HDassert((flags & (unsigned)(~H5AC__READ_ONLY_FLAG)) == 0);
+
     /* Set up user data */
     udata.hdr = hdr;
     udata.parent = parent;
     udata.nelmts = dblk_nelmts;
+    udata.dblk_addr = dblk_addr;
 
     /* Protect the data block */
-    if(NULL == (ret_value = (H5EA_dblock_t *)H5AC_protect(hdr->f, dxpl_id, H5AC_EARRAY_DBLOCK, dblk_addr, &udata, rw)))
+    if(NULL == (ret_value = (H5EA_dblock_t *)H5AC_protect(hdr->f, dxpl_id, H5AC_EARRAY_DBLOCK, dblk_addr, &udata, flags)))
         H5E_THROW(H5E_CANTPROTECT, "unable to protect extensible array data block, address = %llu", (unsigned long long)dblk_addr)
 
 CATCH
@@ -399,7 +403,7 @@ HDfprintf(stderr, "%s: Called\n", FUNC);
     HDassert(dblk_nelmts > 0);
 
     /* Protect data block */
-    if(NULL == (dblock = H5EA__dblock_protect(hdr, dxpl_id, parent, dblk_addr, dblk_nelmts, H5AC_WRITE)))
+    if(NULL == (dblock = H5EA__dblock_protect(hdr, dxpl_id, parent, dblk_addr, dblk_nelmts, H5AC__NO_FLAGS_SET)))
         H5E_THROW(H5E_CANTPROTECT, "unable to protect extensible array data block, address = %llu", (unsigned long long)dblk_addr)
 
     /* Check if this is a paged data block */
diff --git a/src/H5EAhdr.c b/src/H5EAhdr.c
index 76ea6d8..e30bbac 100644
--- a/src/H5EAhdr.c
+++ b/src/H5EAhdr.c
@@ -627,16 +627,25 @@ END_FUNC(PKG)   /* end H5EA__hdr_modified() */
 BEGIN_FUNC(PKG, ERR,
 H5EA_hdr_t *, NULL, NULL,
 H5EA__hdr_protect(H5F_t *f, hid_t dxpl_id, haddr_t ea_addr, void *ctx_udata,
-    H5AC_protect_t rw))
+    unsigned flags))
 
     /* Local variables */
+    H5EA_hdr_cache_ud_t udata;  /* User data for cache callbacks */
 
     /* Sanity check */
     HDassert(f);
     HDassert(H5F_addr_defined(ea_addr));
 
+    /* only the H5AC__READ_ONLY_FLAG may appear in flags */
+    HDassert((flags & (unsigned)(~H5AC__READ_ONLY_FLAG)) == 0);
+
+    /* Set up user data for cache callbacks */
+    udata.f = f;
+    udata.addr = ea_addr;
+    udata.ctx_udata = ctx_udata;
+
     /* Protect the header */
-    if(NULL == (ret_value = (H5EA_hdr_t *)H5AC_protect(f, dxpl_id, H5AC_EARRAY_HDR, ea_addr, ctx_udata, rw)))
+    if(NULL == (ret_value = (H5EA_hdr_t *)H5AC_protect(f, dxpl_id, H5AC_EARRAY_HDR, ea_addr, &udata, flags)))
         H5E_THROW(H5E_CANTPROTECT, "unable to protect extensible array header, address = %llu", (unsigned long long)ea_addr)
 
 CATCH
diff --git a/src/H5EAiblock.c b/src/H5EAiblock.c
index 3c2894a..364b443 100644
--- a/src/H5EAiblock.c
+++ b/src/H5EAiblock.c
@@ -279,7 +279,7 @@ END_FUNC(PKG)   /* end H5EA__iblock_create() */
  */
 BEGIN_FUNC(PKG, ERR,
 H5EA_iblock_t *, NULL, NULL,
-H5EA__iblock_protect(H5EA_hdr_t *hdr, hid_t dxpl_id, H5AC_protect_t rw))
+H5EA__iblock_protect(H5EA_hdr_t *hdr, hid_t dxpl_id, unsigned flags))
 
 #ifdef QAK
 HDfprintf(stderr, "%s: Called\n", FUNC);
@@ -288,8 +288,11 @@ HDfprintf(stderr, "%s: Called\n", FUNC);
     /* Sanity check */
     HDassert(hdr);
 
+    /* only the H5AC__READ_ONLY_FLAG may be set */
+    HDassert((flags & (unsigned)(~H5AC__READ_ONLY_FLAG)) == 0);
+
     /* Protect the index block */
-    if(NULL == (ret_value = (H5EA_iblock_t *)H5AC_protect(hdr->f, dxpl_id, H5AC_EARRAY_IBLOCK, hdr->idx_blk_addr, hdr, rw)))
+    if(NULL == (ret_value = (H5EA_iblock_t *)H5AC_protect(hdr->f, dxpl_id, H5AC_EARRAY_IBLOCK, hdr->idx_blk_addr, hdr, flags)))
         H5E_THROW(H5E_CANTPROTECT, "unable to protect extensible array index block, address = %llu", (unsigned long long)hdr->idx_blk_addr)
 
 CATCH
@@ -361,7 +364,7 @@ HDfprintf(stderr, "%s: Called\n", FUNC);
     HDassert(H5F_addr_defined(hdr->idx_blk_addr));
 
     /* Protect index block */
-    if(NULL == (iblock = H5EA__iblock_protect(hdr, dxpl_id, H5AC_WRITE)))
+    if(NULL == (iblock = H5EA__iblock_protect(hdr, dxpl_id, H5AC__NO_FLAGS_SET)))
         H5E_THROW(H5E_CANTPROTECT, "unable to protect extensible array index block, address = %llu", (unsigned long long)hdr->idx_blk_addr)
 
     /* Check for index block having data block pointers */
@@ -436,7 +439,6 @@ H5EA__iblock_dest(H5EA_iblock_t *iblock))
 
     /* Sanity check */
     HDassert(iblock);
-    HDassert(iblock->rc == 0);
 
     /* Check if shared header field has been initialized */
     if(iblock->hdr) {
diff --git a/src/H5EApkg.h b/src/H5EApkg.h
index 5382eac..d328c05 100644
--- a/src/H5EApkg.h
+++ b/src/H5EApkg.h
@@ -229,7 +229,6 @@ typedef struct H5EA_iblock_t {
     haddr_t     *sblk_addrs;    /* Buffer for addresses of super blocks in index block */
 
     /* Internal array information (not stored) */
-    size_t      rc;             /* Reference count of objects using this block */
     H5EA_hdr_t	*hdr;	        /* Shared array header info	              */
     haddr_t     addr;           /* Address of this index block on disk	      */
     size_t      size;           /* Size of index block on disk		      */
@@ -251,7 +250,6 @@ typedef struct H5EA_sblock_t {
     uint8_t     *page_init;     /* Bitmap of whether a data block page is initialized */
 
     /* Internal array information (not stored) */
-    size_t      rc;             /* Reference count of objects using this block */
     H5EA_hdr_t	*hdr;	        /* Shared array header info	              */
     H5EA_iblock_t *parent;	/* Parent object for super block (index block) */
     haddr_t     addr;           /* Address of this index block on disk	      */
@@ -312,11 +310,19 @@ struct H5EA_t {
 
 /* Metadata cache callback user data types */
 
+/* Info needed for loading header */
+typedef struct H5EA_hdr_cache_ud_t {
+    H5F_t      *f;              /* Pointer to file for extensible array */
+    haddr_t    addr;            /* Address of header on disk */
+    void       *ctx_udata;      /* User context for class */
+} H5EA_hdr_cache_ud_t;
+
 /* Info needed for loading super block */
 typedef struct H5EA_sblock_cache_ud_t {
     H5EA_hdr_t    *hdr;         /* Shared extensible array information */
     H5EA_iblock_t *parent;      /* Pointer to parent object for super block (index block) */
     unsigned sblk_idx;          /* Index of super block */
+    haddr_t sblk_addr;          /* Address of super block */
 } H5EA_sblock_cache_ud_t;
 
 /* Info needed for loading data block */
@@ -324,12 +330,14 @@ typedef struct H5EA_dblock_cache_ud_t {
     H5EA_hdr_t    *hdr;         /* Shared extensible array information */
     void *parent;               /* Pointer to parent object for data block (index or super block) */
     size_t nelmts;              /* Number of elements in data block */
+    haddr_t dblk_addr;          /* Address of data block */
 } H5EA_dblock_cache_ud_t;
 
 /* Info needed for loading data block page */
 typedef struct H5EA_dblk_page_cache_ud_t {
     H5EA_hdr_t    *hdr;         /* Shared extensible array information */
     H5EA_sblock_t *parent;      /* Pointer to parent object for data block page (super block) */
+    haddr_t dblk_page_addr;     /* Address of data block page */
 } H5EA_dblk_page_cache_ud_t;
 
 #ifdef H5EA_TESTING
@@ -388,7 +396,7 @@ H5_DLL herr_t H5EA__hdr_fuse_incr(H5EA_hdr_t *hdr);
 H5_DLL size_t H5EA__hdr_fuse_decr(H5EA_hdr_t *hdr);
 H5_DLL herr_t H5EA__hdr_modified(H5EA_hdr_t *hdr);
 H5_DLL H5EA_hdr_t *H5EA__hdr_protect(H5F_t *f, hid_t dxpl_id, haddr_t ea_addr,
-    void *ctx_udata, H5AC_protect_t rw);
+    void *ctx_udata, unsigned flags);
 H5_DLL herr_t H5EA__hdr_unprotect(H5EA_hdr_t *hdr, hid_t dxpl_id, unsigned cache_flags);
 H5_DLL herr_t H5EA__hdr_delete(H5EA_hdr_t *hdr, hid_t dxpl_id);
 H5_DLL herr_t H5EA__hdr_dest(H5EA_hdr_t *hdr);
@@ -398,7 +406,7 @@ H5_DLL H5EA_iblock_t *H5EA__iblock_alloc(H5EA_hdr_t *hdr);
 H5_DLL haddr_t H5EA__iblock_create(H5EA_hdr_t *hdr, hid_t dxpl_id,
     hbool_t *stats_changed);
 H5_DLL H5EA_iblock_t *H5EA__iblock_protect(H5EA_hdr_t *hdr, hid_t dxpl_id,
-    H5AC_protect_t rw);
+    unsigned flags);
 H5_DLL herr_t H5EA__iblock_unprotect(H5EA_iblock_t *iblock, hid_t dxpl_id,
     unsigned cache_flags);
 H5_DLL herr_t H5EA__iblock_delete(H5EA_hdr_t *hdr, hid_t dxpl_id);
@@ -410,7 +418,8 @@ H5_DLL H5EA_sblock_t *H5EA__sblock_alloc(H5EA_hdr_t *hdr, H5EA_iblock_t *parent,
 H5_DLL haddr_t H5EA__sblock_create(H5EA_hdr_t *hdr, hid_t dxpl_id,
     H5EA_iblock_t *parent, hbool_t *stats_changed, unsigned sblk_idx);
 H5_DLL H5EA_sblock_t *H5EA__sblock_protect(H5EA_hdr_t *hdr, hid_t dxpl_id,
-    H5EA_iblock_t *parent, haddr_t sblk_addr, unsigned sblk_idx, H5AC_protect_t rw);
+    H5EA_iblock_t *parent, haddr_t sblk_addr, unsigned sblk_idx, 
+    unsigned flags);
 H5_DLL herr_t H5EA__sblock_unprotect(H5EA_sblock_t *sblock, hid_t dxpl_id,
     unsigned cache_flags);
 H5_DLL herr_t H5EA__sblock_delete(H5EA_hdr_t *hdr, hid_t dxpl_id,
@@ -424,7 +433,7 @@ H5_DLL haddr_t H5EA__dblock_create(H5EA_hdr_t *hdr, hid_t dxpl_id, void *parent,
     hbool_t *stats_changed, hsize_t dblk_off, size_t nelmts);
 H5_DLL unsigned H5EA__dblock_sblk_idx(const H5EA_hdr_t *hdr, hsize_t idx);
 H5_DLL H5EA_dblock_t *H5EA__dblock_protect(H5EA_hdr_t *hdr, hid_t dxpl_id,
-    void *parent, haddr_t dblk_addr, size_t dblk_nelmts, H5AC_protect_t rw);
+    void *parent, haddr_t dblk_addr, size_t dblk_nelmts, unsigned flags);
 H5_DLL herr_t H5EA__dblock_unprotect(H5EA_dblock_t *dblock, hid_t dxpl_id,
     unsigned cache_flags);
 H5_DLL herr_t H5EA__dblock_delete(H5EA_hdr_t *hdr, hid_t dxpl_id, void *parent,
@@ -436,7 +445,7 @@ H5_DLL H5EA_dblk_page_t *H5EA__dblk_page_alloc(H5EA_hdr_t *hdr, H5EA_sblock_t *p
 H5_DLL herr_t H5EA__dblk_page_create(H5EA_hdr_t *hdr, hid_t dxpl_id,
     H5EA_sblock_t *parent, haddr_t addr);
 H5_DLL H5EA_dblk_page_t *H5EA__dblk_page_protect(H5EA_hdr_t *hdr, hid_t dxpl_id,
-    H5EA_sblock_t *parent, haddr_t dblk_page_addr, H5AC_protect_t rw);
+    H5EA_sblock_t *parent, haddr_t dblk_page_addr, unsigned flags);
 H5_DLL herr_t H5EA__dblk_page_unprotect(H5EA_dblk_page_t *dblk_page,
     hid_t dxpl_id, unsigned cache_flags);
 H5_DLL herr_t H5EA__dblk_page_dest(H5EA_dblk_page_t *dblk_page);
diff --git a/src/H5EAsblock.c b/src/H5EAsblock.c
index 1cc8bd9..33f34c9 100644
--- a/src/H5EAsblock.c
+++ b/src/H5EAsblock.c
@@ -276,7 +276,7 @@ END_FUNC(PKG)   /* end H5EA__sblock_create() */
 BEGIN_FUNC(PKG, ERR,
 H5EA_sblock_t *, NULL, NULL,
 H5EA__sblock_protect(H5EA_hdr_t *hdr, hid_t dxpl_id, H5EA_iblock_t *parent,
-    haddr_t sblk_addr, unsigned sblk_idx, H5AC_protect_t rw))
+    haddr_t sblk_addr, unsigned sblk_idx, unsigned flags))
 
     /* Local variables */
     H5EA_sblock_cache_ud_t udata;      /* Information needed for loading super block */
@@ -290,13 +290,17 @@ HDfprintf(stderr, "%s: Called\n", FUNC);
     HDassert(hdr);
     HDassert(H5F_addr_defined(sblk_addr));
 
+    /* only the H5AC__READ_ONLY_FLAG may be set */
+    HDassert((flags & (unsigned)(~H5AC__READ_ONLY_FLAG)) == 0);
+
     /* Set up user data */
     udata.hdr = hdr;
     udata.parent = parent;
     udata.sblk_idx = sblk_idx;
+    udata.sblk_addr = sblk_addr;
 
     /* Protect the super block */
-    if(NULL == (ret_value = (H5EA_sblock_t *)H5AC_protect(hdr->f, dxpl_id, H5AC_EARRAY_SBLOCK, sblk_addr, &udata, rw)))
+    if(NULL == (ret_value = (H5EA_sblock_t *)H5AC_protect(hdr->f, dxpl_id, H5AC_EARRAY_SBLOCK, sblk_addr, &udata, flags)))
         H5E_THROW(H5E_CANTPROTECT, "unable to protect extensible array super block, address = %llu", (unsigned long long)sblk_addr)
 
 CATCH
@@ -370,7 +374,7 @@ HDfprintf(stderr, "%s: Called\n", FUNC);
     HDassert(H5F_addr_defined(sblk_addr));
 
     /* Protect super block */
-    if(NULL == (sblock = H5EA__sblock_protect(hdr, dxpl_id, parent, sblk_addr, sblk_idx, H5AC_WRITE)))
+    if(NULL == (sblock = H5EA__sblock_protect(hdr, dxpl_id, parent, sblk_addr, sblk_idx, H5AC__NO_FLAGS_SET)))
         H5E_THROW(H5E_CANTPROTECT, "unable to protect extensible array super block, address = %llu", (unsigned long long)sblk_addr)
 
     /* Iterate over data blocks */
@@ -412,7 +416,6 @@ H5EA__sblock_dest(H5EA_sblock_t *sblock))
 
     /* Sanity check */
     HDassert(sblock);
-    HDassert(sblock->rc == 0);
 #ifdef QAK
 HDfprintf(stderr, "%s: sblock->hdr->dblk_page_nelmts = %Zu, sblock->ndblks = %Zu, sblock->dblk_nelmts = %Zu\n", FUNC, sblock->hdr->dblk_page_nelmts, sblock->ndblks, sblock->dblk_nelmts);
 #endif /* QAK */
diff --git a/src/H5FA.c b/src/H5FA.c
index 1acb10b..bfb2a00 100644
--- a/src/H5FA.c
+++ b/src/H5FA.c
@@ -141,7 +141,7 @@ HDfprintf(stderr, "%s: Called\n", FUNC);
 	H5E_THROW(H5E_CANTALLOC, "memory allocation failed for fixed array info")
 
     /* Lock the array header into memory */
-    if(NULL == (hdr = H5FA__hdr_protect(f, dxpl_id, fa_addr, ctx_udata, H5AC_WRITE)))
+    if(NULL == (hdr = H5FA__hdr_protect(f, dxpl_id, fa_addr, ctx_udata, H5AC__NO_FLAGS_SET)))
 	H5E_THROW(H5E_CANTPROTECT, "unable to load fixed array header")
 
     /* Point fixed array wrapper at header and bump it's ref count */
@@ -201,7 +201,7 @@ H5FA_open(H5F_t *f, hid_t dxpl_id, haddr_t fa_addr, void *ctx_udata))
 #ifdef H5FA_DEBUG
 HDfprintf(stderr, "%s: fa_addr = %a\n", FUNC, fa_addr);
 #endif /* H5FA_DEBUG */
-    if(NULL == (hdr = H5FA__hdr_protect(f, dxpl_id, fa_addr, ctx_udata, H5AC_READ)))
+    if(NULL == (hdr = H5FA__hdr_protect(f, dxpl_id, fa_addr, ctx_udata, H5AC__READ_ONLY_FLAG)))
         H5E_THROW(H5E_CANTPROTECT, "unable to load fixed array header, address = %llu", (unsigned long long)fa_addr)
 
     /* Check for pending array deletion */
@@ -359,7 +359,7 @@ HDfprintf(stderr, "%s: fixed array data block address not defined!\n", FUNC, idx
     HDassert(idx < hdr->cparam.nelmts);
 
     /* Protect data block */
-    if(NULL == (dblock = H5FA__dblock_protect(hdr, dxpl_id, hdr->dblk_addr, H5AC_WRITE)))
+    if(NULL == (dblock = H5FA__dblock_protect(hdr, dxpl_id, hdr->dblk_addr, H5AC__NO_FLAGS_SET)))
 	H5E_THROW(H5E_CANTPROTECT, "unable to protect fixed array data block, address = %llu", (unsigned long long)hdr->dblk_addr)
 
     /* Check for paging data block */
@@ -400,7 +400,7 @@ HDfprintf(stderr, "%s: fixed array data block address not defined!\n", FUNC, idx
 	} /* end if */
 
         /* Protect the data block page */
-	if(NULL == (dblk_page = H5FA__dblk_page_protect(hdr, dxpl_id, dblk_page_addr, dblk_page_nelmts, H5AC_WRITE)))
+	if(NULL == (dblk_page = H5FA__dblk_page_protect(hdr, dxpl_id, dblk_page_addr, dblk_page_nelmts, H5AC__NO_FLAGS_SET)))
 	    H5E_THROW(H5E_CANTPROTECT, "unable to protect fixed array data block page, address = %llu", (unsigned long long)dblk_page_addr)
 
         /* Set the element in the data block page */
@@ -467,7 +467,7 @@ HDfprintf(stderr, "%s: Index %Hu\n", FUNC, idx);
     else {
         /* Get the data block */
         HDassert(H5F_addr_defined(hdr->dblk_addr));
-        if(NULL == (dblock = H5FA__dblock_protect(hdr, dxpl_id, hdr->dblk_addr, H5AC_READ)))
+        if(NULL == (dblock = H5FA__dblock_protect(hdr, dxpl_id, hdr->dblk_addr, H5AC__READ_ONLY_FLAG)))
             H5E_THROW(H5E_CANTPROTECT, "unable to protect fixed array data block, address = %llu", (unsigned long long)hdr->dblk_addr)
 
         /* Check for paged data block */
@@ -507,7 +507,7 @@ HDfprintf(stderr, "%s: Index %Hu\n", FUNC, idx);
                     dblk_page_nelmts = dblock->dblk_page_nelmts;
 
                 /* Protect the data block page */
-                if(NULL == (dblk_page = H5FA__dblk_page_protect(hdr, dxpl_id, dblk_page_addr, dblk_page_nelmts, H5AC_READ)))
+                if(NULL == (dblk_page = H5FA__dblk_page_protect(hdr, dxpl_id, dblk_page_addr, dblk_page_nelmts, H5AC__READ_ONLY_FLAG)))
                     H5E_THROW(H5E_CANTPROTECT, "unable to protect fixed array data block page, address = %llu", (unsigned long long)dblk_page_addr)
 
                 /* Retrieve element from data block */
@@ -592,7 +592,7 @@ HDfprintf(stderr, "%s: Called\n", FUNC);
 
         /* Lock the array header into memory */
         /* (OK to pass in NULL for callback context, since we know the header must be in the cache) */
-        if(NULL == (hdr = H5FA__hdr_protect(fa->f, dxpl_id, fa_addr, NULL, H5AC_WRITE)))
+        if(NULL == (hdr = H5FA__hdr_protect(fa->f, dxpl_id, fa_addr, NULL, H5AC__NO_FLAGS_SET)))
             H5E_THROW(H5E_CANTLOAD, "unable to load fixed array header")
 
         /* Set the shared array header's file context for this operation */
@@ -655,7 +655,7 @@ H5FA_delete(H5F_t *f, hid_t dxpl_id, haddr_t fa_addr, void *ctx_udata))
 #ifdef H5FA_DEBUG
 HDfprintf(stderr, "%s: fa_addr = %a\n", FUNC, fa_addr);
 #endif /* H5FA_DEBUG */
-    if(NULL == (hdr = H5FA__hdr_protect(f, dxpl_id, fa_addr, ctx_udata, H5AC_WRITE)))
+    if(NULL == (hdr = H5FA__hdr_protect(f, dxpl_id, fa_addr, ctx_udata, H5AC__NO_FLAGS_SET)))
         H5E_THROW(H5E_CANTPROTECT, "unable to protect fixed array header, address = %llu", (unsigned long long)fa_addr)
 
     /* Check for files using shared array header */
diff --git a/src/H5FAcache.c b/src/H5FAcache.c
index 9a1fc57..b95da40 100644
--- a/src/H5FAcache.c
+++ b/src/H5FAcache.c
@@ -55,11 +55,6 @@
 #define H5FA_HDR_VERSION        0               /* Header */
 #define H5FA_DBLOCK_VERSION     0               /* Data block */
 
-/* Size of stack buffer for serialization buffers */
-#define H5FA_HDR_BUF_SIZE       512
-#define H5FA_DBLOCK_BUF_SIZE    512
-#define H5FA_DBLK_PAGE_BUF_SIZE 512
-
 
 /******************/
 /* Local Typedefs */
@@ -76,23 +71,35 @@
 /********************/
 
 /* Metadata cache (H5AC) callbacks */
-static H5FA_hdr_t *H5FA__cache_hdr_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata);
-static herr_t H5FA__cache_hdr_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5FA_hdr_t *hdr, unsigned * flags_ptr);
-static herr_t H5FA__cache_hdr_clear(H5F_t *f, H5FA_hdr_t *hdr, hbool_t destroy);
-static herr_t H5FA__cache_hdr_size(const H5F_t *f, const H5FA_hdr_t *hdr, size_t *size_ptr);
-static herr_t H5FA__cache_hdr_dest(H5F_t *f, H5FA_hdr_t *hdr);
-
-static H5FA_dblock_t *H5FA__cache_dblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata);
-static herr_t H5FA__cache_dblock_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5FA_dblock_t *dblock, unsigned * flags_ptr);
-static herr_t H5FA__cache_dblock_clear(H5F_t *f, H5FA_dblock_t *dblock, hbool_t destroy);
-static herr_t H5FA__cache_dblock_size(const H5F_t *f, const H5FA_dblock_t *dblock, size_t *size_ptr);
-static herr_t H5FA__cache_dblock_dest(H5F_t *f, H5FA_dblock_t *dblock);
-
-static H5FA_dblk_page_t *H5FA__cache_dblk_page_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata);
-static herr_t H5FA__cache_dblk_page_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5FA_dblk_page_t *dblk_page, unsigned * flags_ptr);
-static herr_t H5FA__cache_dblk_page_clear(H5F_t *f, H5FA_dblk_page_t *dblk_page, hbool_t destroy);
-static herr_t H5FA__cache_dblk_page_size(const H5F_t *f, const H5FA_dblk_page_t *dblk_page, size_t *size_ptr);
-static herr_t H5FA__cache_dblk_page_dest(H5F_t *f, H5FA_dblk_page_t *dblk_page);
+static herr_t H5FA__cache_hdr_get_load_size(const void *udata, size_t *image_len);
+static void *H5FA__cache_hdr_deserialize(const void *image, size_t len,
+    void *udata, hbool_t *dirty);
+static herr_t H5FA__cache_hdr_image_len(const void *thing, size_t *image_len,
+    hbool_t *compressed_ptr, size_t *compressed_image_len_ptr);
+static herr_t H5FA__cache_hdr_serialize(const H5F_t *f, void *image, size_t len,
+    void *thing);
+static herr_t H5FA__cache_hdr_free_icr(void *thing);
+
+static herr_t H5FA__cache_dblock_get_load_size(const void *udata, size_t *image_len);
+static void *H5FA__cache_dblock_deserialize(const void *image, size_t len,
+    void *udata, hbool_t *dirty);
+static herr_t H5FA__cache_dblock_image_len(const void *thing, 
+    size_t *image_len, hbool_t *compressed_ptr, 
+    size_t *compressed_image_len_ptr);
+static herr_t H5FA__cache_dblock_serialize(const H5F_t *f, void *image, size_t len,
+    void *thing);
+static herr_t H5FA__cache_dblock_free_icr(void *thing);
+static herr_t H5FA__cache_dblock_fsf_size(const void *thing, size_t *fsf_size);
+
+static herr_t H5FA__cache_dblk_page_get_load_size(const void *udata, size_t *image_len);
+static void *H5FA__cache_dblk_page_deserialize(const void *image, size_t len,
+    void *udata, hbool_t *dirty);
+static herr_t H5FA__cache_dblk_page_image_len(const void *thing, 
+    size_t *image_len, hbool_t *compressed_ptr, 
+    size_t *compressed_image_len_ptr);
+static herr_t H5FA__cache_dblk_page_serialize(const H5F_t *f, void *image, size_t len,
+    void *thing);
+static herr_t H5FA__cache_dblk_page_free_icr(void *thing);
 
 
 /*********************/
@@ -101,36 +108,53 @@ static herr_t H5FA__cache_dblk_page_dest(H5F_t *f, H5FA_dblk_page_t *dblk_page);
 
 /* H5FA header inherits cache-like properties from H5AC */
 const H5AC_class_t H5AC_FARRAY_HDR[1] = {{
-    H5AC_FARRAY_HDR_ID,
-    (H5AC_load_func_t)H5FA__cache_hdr_load,
-    (H5AC_flush_func_t)H5FA__cache_hdr_flush,
-    (H5AC_dest_func_t)H5FA__cache_hdr_dest,
-    (H5AC_clear_func_t)H5FA__cache_hdr_clear,
-    (H5AC_notify_func_t)NULL,
-    (H5AC_size_func_t)H5FA__cache_hdr_size,
+    H5AC_FARRAY_HDR_ID,                 /* Metadata client ID */
+    "Fixed-array Header",               /* Metadata client name (for debugging) */
+    H5FD_MEM_FARRAY_HDR,                /* File space memory type for client */
+    H5AC__CLASS_NO_FLAGS_SET,           /* Client class behavior flags */
+    H5FA__cache_hdr_get_load_size,      /* 'get_load_size' callback */
+    H5FA__cache_hdr_deserialize,        /* 'deserialize' callback */
+    H5FA__cache_hdr_image_len,          /* 'image_len' callback */
+    NULL,                               /* 'pre_serialize' callback */
+    H5FA__cache_hdr_serialize,          /* 'serialize' callback */
+    NULL,                               /* 'notify' callback */
+    H5FA__cache_hdr_free_icr,           /* 'free_icr' callback */
+    NULL,				/* 'clear' callback */
+    NULL,                               /* 'fsf_size' callback */
 }};
 
-
 /* H5FA data block inherits cache-like properties from H5AC */
 const H5AC_class_t H5AC_FARRAY_DBLOCK[1] = {{
-    H5AC_FARRAY_DBLOCK_ID,
-    (H5AC_load_func_t)H5FA__cache_dblock_load,
-    (H5AC_flush_func_t)H5FA__cache_dblock_flush,
-    (H5AC_dest_func_t)H5FA__cache_dblock_dest,
-    (H5AC_clear_func_t)H5FA__cache_dblock_clear,
-    (H5AC_notify_func_t)NULL,
-    (H5AC_size_func_t)H5FA__cache_dblock_size,
+    H5AC_FARRAY_DBLOCK_ID,              /* Metadata client ID */
+    "Fixed Array Data Block",           /* Metadata client name (for debugging) */
+    H5FD_MEM_FARRAY_DBLOCK,             /* File space memory type for client */
+    H5AC__CLASS_NO_FLAGS_SET,           /* Client class behavior flags */
+    H5FA__cache_dblock_get_load_size,   /* 'get_load_size' callback */
+    H5FA__cache_dblock_deserialize,     /* 'deserialize' callback */
+    H5FA__cache_dblock_image_len,       /* 'image_len' callback */
+    NULL,                               /* 'pre_serialize' callback */
+    H5FA__cache_dblock_serialize,       /* 'serialize' callback */
+    NULL,                               /* 'notify' callback */
+    H5FA__cache_dblock_free_icr,        /* 'free_icr' callback */
+    NULL,				/* 'clear' callback */
+    H5FA__cache_dblock_fsf_size,        /* 'fsf_size' callback */
 }};
 
 /* H5FA data block page inherits cache-like properties from H5AC */
 const H5AC_class_t H5AC_FARRAY_DBLK_PAGE[1] = {{
-    H5AC_FARRAY_DBLK_PAGE_ID,
-    (H5AC_load_func_t)H5FA__cache_dblk_page_load,
-    (H5AC_flush_func_t)H5FA__cache_dblk_page_flush,
-    (H5AC_dest_func_t)H5FA__cache_dblk_page_dest,
-    (H5AC_clear_func_t)H5FA__cache_dblk_page_clear,
-    (H5AC_notify_func_t)NULL,
-    (H5AC_size_func_t)H5FA__cache_dblk_page_size,
+    H5AC_FARRAY_DBLK_PAGE_ID,           /* Metadata client ID */
+    "Fixed Array Data Block Page",      /* Metadata client name (for debugging) */
+    H5FD_MEM_FARRAY_DBLK_PAGE,          /* File space memory type for client */
+    H5AC__CLASS_NO_FLAGS_SET,           /* Client class behavior flags */
+    H5FA__cache_dblk_page_get_load_size, /* 'get_load_size' callback */
+    H5FA__cache_dblk_page_deserialize,  /* 'deserialize' callback */
+    H5FA__cache_dblk_page_image_len,    /* 'image_len' callback */
+    NULL,                               /* 'pre_serialize' callback */
+    H5FA__cache_dblk_page_serialize,    /* 'serialize' callback */
+    NULL,                               /* 'notify' callback */
+    H5FA__cache_dblk_page_free_icr,     /* 'free_icr' callback */
+    NULL,				/* 'clear' callback */
+    NULL,                               /* 'fsf_size' callback */
 }};
 
 
@@ -146,88 +170,101 @@ const H5AC_class_t H5AC_FARRAY_DBLK_PAGE[1] = {{
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5FA__cache_hdr_load
+ * Function:    H5FA__cache_hdr_get_load_size
+ *
+ * Purpose:     Compute the size of the data structure on disk.
+ *
+ * Return:      Non-negative on success/Negative on failure
+ *
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              July 31, 2013
+ *
+ *-------------------------------------------------------------------------
+ */
+BEGIN_FUNC(STATIC, NOERR,
+herr_t, SUCCEED, -,
+H5FA__cache_hdr_get_load_size(const void *_udata, size_t *image_len))
+
+    /* Local variables */
+    const H5FA_hdr_cache_ud_t *udata = (const H5FA_hdr_cache_ud_t *)_udata; /* User data for callback */
+
+    /* Check arguments */
+    HDassert(udata);
+    HDassert(udata->f);
+    HDassert(image_len);
+
+    /* Set the image length size */
+    *image_len = (size_t)H5FA_HEADER_SIZE_FILE(udata->f);
+
+END_FUNC(STATIC)   /* end H5FA__cache_hdr_get_load_size() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5FA__cache_hdr_deserialize
  *
- * Purpose:	Loads a fixed array header from the disk.
+ * Purpose:	Loads a data structure from the disk.
  *
- * Return:	Success:	Pointer to a new fixed array
+ * Return:	Success:	Pointer to a new B-tree.
  *		Failure:	NULL
  *
- * Programmer:	Vailin Choi
- *              Thursday, April 30, 2009
+ * Programmer:	Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              August 12, 2013
  *
  *-------------------------------------------------------------------------
  */
 BEGIN_FUNC(STATIC, ERR,
-H5FA_hdr_t *, NULL, NULL,
-H5FA__cache_hdr_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata))
+void *, NULL, NULL,
+H5FA__cache_hdr_deserialize(const void *_image, size_t len,
+    void *_udata, hbool_t H5_ATTR_UNUSED *dirty))
 
     /* Local variables */
     H5FA_cls_id_t       id;		/* ID of fixed array class, as found in file */
     H5FA_hdr_t		*hdr = NULL;    /* Fixed array info */
-    size_t		size;           /* Header size */
-    H5WB_t              *wb = NULL;     /* Wrapped buffer for header data */
-    uint8_t             hdr_buf[H5FA_HDR_BUF_SIZE]; /* Buffer for header */
-    uint8_t		*buf;           /* Pointer to header buffer */
-    const uint8_t	*p;             /* Pointer into raw data buffer */
+    H5FA_hdr_cache_ud_t *udata = (H5FA_hdr_cache_ud_t *)_udata;
+    const uint8_t	*image = (const uint8_t *)_image;       /* Pointer into raw data buffer */
     uint32_t            stored_chksum;  /* Stored metadata checksum value */
     uint32_t            computed_chksum; /* Computed metadata checksum value */
 
     /* Check arguments */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
+    HDassert(udata);
+    HDassert(udata->f);
+    HDassert(H5F_addr_defined(udata->addr));
 
     /* Allocate space for the fixed array data structure */
-    if(NULL == (hdr = H5FA__hdr_alloc(f)))
+    if(NULL == (hdr = H5FA__hdr_alloc(udata->f)))
 	H5E_THROW(H5E_CANTALLOC, "memory allocation failed for fixed array shared header")
 
     /* Set the fixed array header's address */
-    hdr->addr = addr;
-
-    /* Wrap the local buffer for serialized info */
-    if(NULL == (wb = H5WB_wrap(hdr_buf, sizeof(hdr_buf))))
-	H5E_THROW(H5E_CANTINIT, "can't wrap buffer")
-
-    /* Compute the 'base' size of the fixed array header on disk */
-    size = H5FA_HEADER_SIZE_HDR(hdr);
-
-    /* Get a pointer to a buffer that's large enough for serialized header */
-    if(NULL == (buf = (uint8_t *)H5WB_actual(wb, size)))
-	H5E_THROW(H5E_CANTGET, "can't get actual buffer")
-
-    /* Read header from disk */
-    if(H5F_block_read(f, H5FD_MEM_FARRAY_HDR, addr, size, dxpl_id, buf) < 0)
-	H5E_THROW(H5E_READERROR, "can't read fixed array header")
-
-    /* Get temporary pointer to serialized header */
-    p = buf;
+    hdr->addr = udata->addr;
 
     /* Magic number */
-    if(HDmemcmp(p, H5FA_HDR_MAGIC, (size_t)H5_SIZEOF_MAGIC))
+    if(HDmemcmp(image, H5FA_HDR_MAGIC, (size_t)H5_SIZEOF_MAGIC))
 	H5E_THROW(H5E_BADVALUE, "wrong fixed array header signature")
-    p += H5_SIZEOF_MAGIC;
+    image += H5_SIZEOF_MAGIC;
 
     /* Version */
-    if(*p++ != H5FA_HDR_VERSION)
+    if(*image++ != H5FA_HDR_VERSION)
 	H5E_THROW(H5E_VERSION, "wrong fixed array header version")
 
     /* Fixed array class */
-    id = (H5FA_cls_id_t)*p++;
+    id = (H5FA_cls_id_t)*image++;
     if(id >= H5FA_NUM_CLS_ID)
 	H5E_THROW(H5E_BADTYPE, "incorrect fixed array class")
     hdr->cparam.cls = H5FA_client_class_g[id];
 
     /* General array creation/configuration information */
-    hdr->cparam.raw_elmt_size = *p++;         	   /* Element size in file (in bytes) */
-    hdr->cparam.max_dblk_page_nelmts_bits = *p++;  /* Log2(Max. # of elements in data block page) -
-						      i.e. # of bits needed to store max. # of
-						      elements in data block page. */
+    hdr->cparam.raw_elmt_size = *image++;             /* Element size in file (in bytes) */
+    hdr->cparam.max_dblk_page_nelmts_bits = *image++; /* Log2(Max. # of elements in data block page) -
+						         i.e. # of bits needed to store max. # of
+						         elements in data block page. */
 
     /* Array statistics */
-    H5F_DECODE_LENGTH(f, p, hdr->cparam.nelmts);	/* Number of elements */
+    H5F_DECODE_LENGTH(udata->f, image, hdr->cparam.nelmts);	/* Number of elements */
 
     /* Internal information */
-    H5F_addr_decode(f, &p, &hdr->dblk_addr); 		/* Address of index block */
+    H5F_addr_decode(udata->f, &image, &hdr->dblk_addr); 		/* Address of index block */
 
     /* Check for data block */
     if(H5F_addr_defined(hdr->dblk_addr)) {
@@ -250,26 +287,26 @@ H5FA__cache_hdr_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata))
 
     /* Sanity check */
     /* (allow for checksum not decoded yet) */
-    HDassert((size_t)(p - buf) == (size - H5FA_SIZEOF_CHKSUM));
+    HDassert((size_t)(image - (const uint8_t *)_image) == (len - H5FA_SIZEOF_CHKSUM));
 
     /* Compute checksum on entire header */
     /* (including the filter information, if present) */
-    computed_chksum = H5_checksum_metadata(buf, (size_t)(p - buf), 0);
+    computed_chksum = H5_checksum_metadata(_image, (size_t)(image - (const uint8_t *)_image), 0);
 
     /* Metadata checksum */
-    UINT32DECODE(p, stored_chksum);
+    UINT32DECODE(image, stored_chksum);
 
     /* Sanity check */
-    HDassert((size_t)(p - buf) == size);
+    HDassert((size_t)(image - (const uint8_t *)_image) == len);
 
     /* Verify checksum */
     if(stored_chksum != computed_chksum)
 	H5E_THROW(H5E_BADVALUE, "incorrect metadata checksum for fixed array header")
 
     /* Finish initializing fixed array header */
-    if(H5FA__hdr_init(hdr, udata) < 0)
+    if(H5FA__hdr_init(hdr, udata->ctx_udata) < 0)
 	H5E_THROW(H5E_CANTINIT, "initialization failed for fixed array header")
-    HDassert(hdr->size == size);
+    HDassert(hdr->size == len);
 
     /* Set return value */
     ret_value = hdr;
@@ -277,326 +314,277 @@ H5FA__cache_hdr_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata))
 CATCH
 
     /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-	H5E_THROW(H5E_CLOSEERROR, "can't close wrapped buffer")
     if(!ret_value)
         if(hdr && H5FA__hdr_dest(hdr) < 0)
             H5E_THROW(H5E_CANTFREE, "unable to destroy fixed array header")
 
-END_FUNC(STATIC)   /* end H5FA__cache_hdr_load() */
+END_FUNC(STATIC)   /* end H5FA__cache_hdr_deserialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5FA__cache_hdr_flush
+ * Function:    H5FA__cache_hdr_image_len
  *
- * Purpose:	Flushes a dirty fixed array header to disk.
+ * Purpose:     Compute the size of the data structure on disk.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Vailin Choi
- *              Thursday, April 30, 2009
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              August 12, 2013
  *
  *-------------------------------------------------------------------------
  */
-BEGIN_FUNC(STATIC, ERR,
-herr_t, SUCCEED, FAIL,
-H5FA__cache_hdr_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr,
-    H5FA_hdr_t *hdr, unsigned H5_ATTR_UNUSED * flags_ptr))
+BEGIN_FUNC(STATIC, NOERR,
+herr_t, SUCCEED, -,
+H5FA__cache_hdr_image_len(const void *_thing, size_t *image_len,
+    hbool_t H5_ATTR_UNUSED *compressed_ptr, size_t H5_ATTR_UNUSED *compressed_image_len_ptr))
 
-    H5WB_t *wb = NULL;                  /* Wrapped buffer for header data */
-    uint8_t hdr_buf[H5FA_HDR_BUF_SIZE]; /* Buffer for header */
+    /* Local variables */
+    const H5FA_hdr_t *hdr = (const H5FA_hdr_t *)_thing;      /* Pointer to the object */
 
-    /* check arguments */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
+    /* Check arguments */
     HDassert(hdr);
+    HDassert(image_len);
 
-    if(hdr->cache_info.is_dirty) {
-        uint8_t	*buf;           /* Temporary raw data buffer */
-        uint8_t *p;             /* Pointer into raw data buffer */
-        size_t	size;           /* Header size on disk */
-        uint32_t metadata_chksum; /* Computed metadata checksum value */
-
-        /* Wrap the local buffer for serialized header info */
-        if(NULL == (wb = H5WB_wrap(hdr_buf, sizeof(hdr_buf))))
-            H5E_THROW(H5E_CANTINIT, "can't wrap buffer")
-
-        /* Compute the size of the array header on disk */
-        size = hdr->size;
-
-        /* Get a pointer to a buffer that's large enough for serialized header */
-        if(NULL == (buf = (uint8_t *)H5WB_actual(wb, size)))
-            H5E_THROW(H5E_CANTGET, "can't get actual buffer")
-
-        /* Get temporary pointer to serialized header */
-        p = buf;
+    /* Set the image length size */
+    *image_len = hdr->size;
 
-        /* Magic number */
-        HDmemcpy(p, H5FA_HDR_MAGIC, (size_t)H5_SIZEOF_MAGIC);
-        p += H5_SIZEOF_MAGIC;
+END_FUNC(STATIC)   /* end H5FA__cache_hdr_image_len() */
 
-        /* Version # */
-        *p++ = H5FA_HDR_VERSION;
+
+/*-------------------------------------------------------------------------
+ * Function:	H5FA__cache_hdr_serialize
+ *
+ * Purpose:	Flushes a dirty object to disk.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              August 12, 2013
+ *
+ *-------------------------------------------------------------------------
+ */
+BEGIN_FUNC(STATIC, NOERR,
+herr_t, SUCCEED, -,
+H5FA__cache_hdr_serialize(const H5F_t *f, void *_image, size_t H5_ATTR_UNUSED len,
+    void *_thing))
 
-        /* Fixed array type */
-        *p++ = hdr->cparam.cls->id;
+    /* Local variables */
+    H5FA_hdr_t *hdr = (H5FA_hdr_t *)_thing;     /* Pointer to the fixed array header */
+    uint8_t *image = (uint8_t *)_image;         /* Pointer into raw data buffer */
+    uint32_t metadata_chksum;   /* Computed metadata checksum value */
 
-        /* General array creation/configuration information */
-        *p++ = hdr->cparam.raw_elmt_size;          /* Element size in file (in bytes) */
-        *p++ = hdr->cparam.max_dblk_page_nelmts_bits;  /* Log2(Max. # of elements in data block page) - i.e. # of bits needed to store max. # of elements in data block page */
+    /* check arguments */
+    HDassert(f);
+    HDassert(image);
+    HDassert(hdr);
 
-        /* Array statistics */
-        H5F_ENCODE_LENGTH(f, p, hdr->stats.nelmts);       /* Number of elements for the fixed array */
+    /* Magic number */
+    HDmemcpy(image, H5FA_HDR_MAGIC, (size_t)H5_SIZEOF_MAGIC);
+    image += H5_SIZEOF_MAGIC;
 
-        /* Internal information */
-        H5F_addr_encode(f, &p, hdr->dblk_addr);  /* Address of fixed array data block */
+    /* Version # */
+    *image++ = H5FA_HDR_VERSION;
 
-        /* Compute metadata checksum */
-        metadata_chksum = H5_checksum_metadata(buf, (size_t)(p - buf), 0);
+    /* Fixed array type */
+    *image++ = hdr->cparam.cls->id;
 
-        /* Metadata checksum */
-        UINT32ENCODE(p, metadata_chksum);
+    /* General array creation/configuration information */
+    *image++ = hdr->cparam.raw_elmt_size;          /* Element size in file (in bytes) */
+    *image++ = hdr->cparam.max_dblk_page_nelmts_bits;  /* Log2(Max. # of elements in data block page) - i.e. # of bits needed to store max. # of elements in data block page */
 
-	/* Write the array header. */
-        HDassert((size_t)(p - buf) == size);
-	if(H5F_block_write(f, H5FD_MEM_FARRAY_HDR, addr, size, dxpl_id, buf) < 0)
-            H5E_THROW(H5E_WRITEERROR, "unable to save fixed array header to disk")
+    /* Array statistics */
+    H5F_ENCODE_LENGTH(f, image, hdr->stats.nelmts);       /* Number of elements for the fixed array */
 
-	hdr->cache_info.is_dirty = FALSE;
-    } /* end if */
+    /* Internal information */
+    H5F_addr_encode(f, &image, hdr->dblk_addr);  /* Address of fixed array data block */
 
-    if(destroy)
-        if(H5FA__cache_hdr_dest(f, hdr) < 0)
-            H5E_THROW(H5E_CANTFREE, "unable to destroy fixed array header")
+    /* Compute metadata checksum */
+    metadata_chksum = H5_checksum_metadata(_image, (size_t)(image - (uint8_t *)_image), 0);
 
-CATCH
+    /* Metadata checksum */
+    UINT32ENCODE(image, metadata_chksum);
 
-    /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-	H5E_THROW(H5E_CLOSEERROR, "can't close wrapped buffer")
+    /* Sanity check */
+    HDassert((size_t)(image - (uint8_t *)_image) == len);
 
-END_FUNC(STATIC)   /* end H5FA__cache_hdr_flush() */
+END_FUNC(STATIC)   /* end H5FA__cache_hdr_serialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5FA__cache_hdr_clear
+ * Function:	H5FA__cache_hdr_free_icr
  *
- * Purpose:	Mark a fixed array header in memory as non-dirty.
+ * Purpose:	Destroy/release an "in core representation" of a data
+ *              structure
  *
  * Return:	Non-negative on success/Negative on failure
  *
- * Programmer:	Vailin Choi
- *              Thursday, April 30, 2009
+ * Programmer:	Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              August 12, 2013
  *
  *-------------------------------------------------------------------------
  */
 BEGIN_FUNC(STATIC, ERR,
 herr_t, SUCCEED, FAIL,
-H5FA__cache_hdr_clear(H5F_t *f, H5FA_hdr_t *hdr, hbool_t destroy))
-
-    /* Sanity check */
-    HDassert(hdr);
+H5FA__cache_hdr_free_icr(void *thing))
 
-    /* Reset the dirty flag.  */
-    hdr->cache_info.is_dirty = FALSE;
+    /* Check arguments */
+    HDassert(thing);
 
-    if(destroy)
-        if(H5FA__cache_hdr_dest(f, hdr) < 0)
-            H5E_THROW(H5E_CANTFREE, "unable to destroy fixed array header")
+    /* Release the extensible array header */
+    if(H5FA__hdr_dest((H5FA_hdr_t *)thing) < 0)
+        H5E_THROW(H5E_CANTFREE, "can't free fixed array header")
 
 CATCH
 
-END_FUNC(STATIC)   /* end H5FA__cache_hdr_clear() */
+END_FUNC(STATIC)   /* end H5FA__cache_hdr_free_icr() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5FA__cache_hdr_size
+ * Function:    H5FA__cache_dblock_get_load_size
  *
- * Purpose:	Compute the size in bytes of a fixed array header
- *		on disk, and return it in *size_ptr.  On failure,
- *		the value of *size_ptr is undefined.
+ * Purpose:     Compute the size of the data structure on disk.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Vailin Choi
- *              Thursday, April 30, 2009
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              August 12, 2013
  *
  *-------------------------------------------------------------------------
  */
-/* ARGSUSED */
 BEGIN_FUNC(STATIC, NOERR,
 herr_t, SUCCEED, -,
-H5FA__cache_hdr_size(const H5F_t H5_ATTR_UNUSED *f, const H5FA_hdr_t *hdr,
-    size_t *size_ptr))
-
-    /* Sanity check */
-    HDassert(f);
-    HDassert(hdr);
-    HDassert(size_ptr);
-
-    /* Set size value */
-    *size_ptr = hdr->size;
-
-END_FUNC(STATIC)   /* end H5FA__cache_hdr_size() */
+H5FA__cache_dblock_get_load_size(const void *_udata, size_t *image_len))
 
-
-/*-------------------------------------------------------------------------
- * Function:	H5FA__cache_hdr_dest
- *
- * Purpose:	Destroys a fixed array header in memory.
- *
- * Return:	Non-negative on success/Negative on failure
- *
- * Programmer:	Vailin Choi
- *              Thursday, April 30, 2009
- *
- *-------------------------------------------------------------------------
- */
-/* ARGSUSED */
-BEGIN_FUNC(STATIC, ERR,
-herr_t, SUCCEED, FAIL,
-H5FA__cache_hdr_dest(H5F_t *f, H5FA_hdr_t *hdr))
+    /* Local variables */
+    const H5FA_dblock_cache_ud_t *udata = (const H5FA_dblock_cache_ud_t *)_udata;      /* User data */
+    H5FA_dblock_t dblock;           /* Fake data block for computing size */
+    size_t	dblk_page_nelmts;	/* # of elements per data block page */
 
     /* Check arguments */
-    HDassert(f);
-    HDassert(hdr);
-
-    /* Verify that header is clean */
-    HDassert(hdr->cache_info.is_dirty == FALSE);
-
-    /* If we're going to free the space on disk, the address must be valid */
-    HDassert(!hdr->cache_info.free_file_space_on_destroy || H5F_addr_defined(hdr->cache_info.addr));
-
-    /* Check for freeing file space for fixed array header */
-    if(hdr->cache_info.free_file_space_on_destroy) {
-        /* Sanity check address */
-        HDassert(H5F_addr_eq(hdr->addr, hdr->cache_info.addr));
-
-        /* Release the space on disk */
-        /* (XXX: Nasty usage of internal DXPL value! -QAK) */
-        if(H5MF_xfree(f, H5FD_MEM_FARRAY_HDR, H5AC_dxpl_id, hdr->cache_info.addr, (hsize_t)hdr->size) < 0)
-            H5E_THROW(H5E_CANTFREE, "unable to free fixed array header")
+    HDassert(udata);
+    HDassert(udata->hdr);
+    HDassert(image_len);
+
+    /* Set up fake data block for computing size on disk */
+    /* (Note: extracted from H5FA__dblock_alloc) */
+    HDmemset(&dblock, 0, sizeof(dblock));
+
+    /* Set up fake data block for computing size on disk
+     *
+     * need: dblock->hdr
+     *       dblock->npages
+     *       dblock->dblk_page_init_size
+     */
+
+    dblock.hdr = udata->hdr;
+    dblk_page_nelmts = (size_t)1 << udata->hdr->cparam.max_dblk_page_nelmts_bits;
+    if(udata->hdr->cparam.nelmts > dblk_page_nelmts) {
+        dblock.npages = (size_t)(((udata->hdr->cparam.nelmts + dblk_page_nelmts) - 1) / dblk_page_nelmts);
+        dblock.dblk_page_init_size = (dblock.npages + 7) / 8;
     } /* end if */
 
-    /* Release the fixed array header */
-    if(H5FA__hdr_dest(hdr) < 0)
-        H5E_THROW(H5E_CANTFREE, "can't free fixed array header")
-
-CATCH
+    /* Set the image length size */
+    if(!dblock.npages)
+        *image_len = (size_t)H5FA_DBLOCK_SIZE(&dblock);
+    else
+        *image_len = (size_t)H5FA_DBLOCK_PREFIX_SIZE(&dblock);
 
-END_FUNC(STATIC)   /* end H5FA__cache_hdr_dest() */
+END_FUNC(STATIC)   /* end H5FA__cache_dblock_get_load_size() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5FA__cache_dblock_load
+ * Function:	H5FA__cache_dblock_deserialize
  *
- * Purpose:	Loads a fixed array data block from the disk.
+ * Purpose:	Loads a data structure from the disk.
  *
- * Return:	Success:	Pointer to a new fixed array data block
+ * Return:	Success:	Pointer to a new B-tree.
  *		Failure:	NULL
  *
- * Programmer:	Vailin Choi
- *              Thursday, April 30, 2009
+ * Programmer:	Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              August 14, 2013
  *
  *-------------------------------------------------------------------------
  */
 BEGIN_FUNC(STATIC, ERR,
-H5FA_dblock_t *, NULL, NULL,
-H5FA__cache_dblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata))
+void *, NULL, NULL,
+H5FA__cache_dblock_deserialize(const void *_image, size_t len,
+    void *_udata, hbool_t H5_ATTR_UNUSED *dirty))
 
     /* Local variables */
     H5FA_dblock_t  *dblock = NULL;  /* Data block info */
     H5FA_dblock_cache_ud_t *udata = (H5FA_dblock_cache_ud_t *)_udata; /* User data for loading data block */
-    size_t	   size;            /* Data block size */
-    H5WB_t         *wb = NULL;      /* Wrapped buffer for data block data */
-    uint8_t        dblock_buf[H5FA_DBLOCK_BUF_SIZE]; /* Buffer for data block */
-    uint8_t	   *buf;             /* Pointer to data block buffer */
-    const uint8_t  *p;              /* Pointer into raw data buffer */
+    const uint8_t  *image = (const uint8_t *)_image;    /* Pointer into raw data buffer */
     uint32_t       stored_chksum;   /* Stored metadata checksum value */
     uint32_t       computed_chksum; /* Computed metadata checksum value */
     haddr_t        arr_addr;        /* Address of array header in the file */
 
     /* Sanity check */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
-    HDassert(udata && udata->hdr);
+    HDassert(udata);
+    HDassert(udata->hdr);
 
     /* Allocate the fixed array data block */
     if(NULL == (dblock = H5FA__dblock_alloc(udata->hdr)))
 	H5E_THROW(H5E_CANTALLOC, "memory allocation failed for fixed array data block")
 
-    /* Set the fixed array data block's information */
-    dblock->addr = addr;
-
-    /* Wrap the local buffer for serialized info */
-    if(NULL == (wb = H5WB_wrap(dblock_buf, sizeof(dblock_buf))))
-	H5E_THROW(H5E_CANTINIT, "can't wrap buffer")
-
-    /* Compute the size of the fixed array data block on disk */
-    if(!dblock->npages)
-        size = (size_t)H5FA_DBLOCK_SIZE(dblock);
-    else
-        size = H5FA_DBLOCK_PREFIX_SIZE(dblock);
-
-    /* Get a pointer to a buffer that's large enough for serialized info */
-    if(NULL == (buf = (uint8_t *)H5WB_actual(wb, size)))
-	H5E_THROW(H5E_CANTGET, "can't get actual buffer")
+    HDassert(((!dblock->npages) && (len == (size_t)H5FA_DBLOCK_SIZE(dblock))) 
+             || (len == (size_t)H5FA_DBLOCK_PREFIX_SIZE(dblock)));
 
-    /* Read data block from disk */
-    if(H5F_block_read(f, H5FD_MEM_FARRAY_DBLOCK, addr, size, dxpl_id, buf) < 0)
-	H5E_THROW(H5E_READERROR, "can't read fixed array data block")
-
-    /* Get temporary pointer to serialized header */
-    p = buf;
+    /* Set the fixed array data block's information */
+    dblock->addr = udata->dblk_addr;
 
     /* Magic number */
-    if(HDmemcmp(p, H5FA_DBLOCK_MAGIC, (size_t)H5_SIZEOF_MAGIC))
+    if(HDmemcmp(image, H5FA_DBLOCK_MAGIC, (size_t)H5_SIZEOF_MAGIC))
 	H5E_THROW(H5E_BADVALUE, "wrong fixed array data block signature")
-    p += H5_SIZEOF_MAGIC;
+    image += H5_SIZEOF_MAGIC;
 
     /* Version */
-    if(*p++ != H5FA_DBLOCK_VERSION)
+    if(*image++ != H5FA_DBLOCK_VERSION)
 	H5E_THROW(H5E_VERSION, "wrong fixed array data block version")
 
     /* Fixed array type */
-    if(*p++ != (uint8_t)udata->hdr->cparam.cls->id)
+    if(*image++ != (uint8_t)udata->hdr->cparam.cls->id)
 	H5E_THROW(H5E_BADTYPE, "incorrect fixed array class")
 
     /* Address of header for array that owns this block (just for file integrity checks) */
-    H5F_addr_decode(f, &p, &arr_addr);
+    H5F_addr_decode(udata->hdr->f, &image, &arr_addr);
     if(H5F_addr_ne(arr_addr, udata->hdr->addr))
 	H5E_THROW(H5E_BADVALUE, "wrong fixed array header address")
 
     /* Page initialization flags */
     if(dblock->npages > 0) {
-	HDmemcpy(dblock->dblk_page_init, p, dblock->dblk_page_init_size);
-        p += dblock->dblk_page_init_size;
+	HDmemcpy(dblock->dblk_page_init, image, dblock->dblk_page_init_size);
+        image += dblock->dblk_page_init_size;
     } /* end if */
 
     /* Only decode elements if the data block is not paged */
     if(!dblock->npages) {
         /* Decode elements in data block */
         /* Convert from raw elements on disk into native elements in memory */
-        if((udata->hdr->cparam.cls->decode)(p, dblock->elmts, (size_t)udata->hdr->stats.nelmts, udata->hdr->cb_ctx) < 0)
+        if((udata->hdr->cparam.cls->decode)(image, dblock->elmts, (size_t)udata->hdr->cparam.nelmts, udata->hdr->cb_ctx) < 0)
             H5E_THROW(H5E_CANTDECODE, "can't decode fixed array data elements")
-        p += (udata->hdr->stats.nelmts * udata->hdr->cparam.raw_elmt_size);
+        image += (udata->hdr->cparam.nelmts * udata->hdr->cparam.raw_elmt_size);
     } /* end if */
 
     /* Sanity check */
     /* (allow for checksum not decoded yet) */
-    HDassert((size_t)(p - buf) == (size - H5FA_SIZEOF_CHKSUM));
+    HDassert((size_t)(image - (const uint8_t *)_image) == (len - H5FA_SIZEOF_CHKSUM));
 
     /* Set the data block's size */
     dblock->size = H5FA_DBLOCK_SIZE(dblock);
 
     /* Compute checksum on data block */
-    computed_chksum = H5_checksum_metadata(buf, (size_t)(p - buf), 0);
+    computed_chksum = H5_checksum_metadata(_image, (size_t)(image - (const uint8_t *)_image), 0);
 
     /* Metadata checksum */
-    UINT32DECODE(p, stored_chksum);
+    UINT32DECODE(image, stored_chksum);
 
     /* Sanity check */
-    HDassert((size_t)(p - buf) == size);
+    HDassert((size_t)(image - (const uint8_t *)_image) == len);
 
     /* Verify checksum */
     if(stored_chksum != computed_chksum)
@@ -608,317 +596,292 @@ H5FA__cache_dblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata))
 CATCH
 
     /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-	H5E_THROW(H5E_CLOSEERROR, "can't close wrapped buffer")
     if(!ret_value)
         if(dblock && H5FA__dblock_dest(dblock) < 0)
             H5E_THROW(H5E_CANTFREE, "unable to destroy fixed array data block")
 
-END_FUNC(STATIC)   /* end H5FA__cache_dblock_load() */
+END_FUNC(STATIC)   /* end H5FA__cache_dblock_deserialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5FA__cache_dblock_flush
+ * Function:    H5FA__cache_dblock_image_len
  *
- * Purpose:	Flushes a dirty fixed array data block to disk.
+ * Purpose:     Compute the size of the data structure on disk.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Vailin Choi
- *              Thursday, April 30, 2009
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              August 14, 2013
  *
  *-------------------------------------------------------------------------
  */
-BEGIN_FUNC(STATIC, ERR,
-herr_t, SUCCEED, FAIL,
-H5FA__cache_dblock_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr,
-    H5FA_dblock_t *dblock, unsigned H5_ATTR_UNUSED * flags_ptr))
+BEGIN_FUNC(STATIC, NOERR,
+herr_t, SUCCEED, -,
+H5FA__cache_dblock_image_len(const void *_thing, size_t *image_len,
+    hbool_t H5_ATTR_UNUSED *compressed_ptr, size_t H5_ATTR_UNUSED *compressed_image_len_ptr))
 
     /* Local variables */
-    H5WB_t *wb = NULL;                     /* Wrapped buffer for serializing data */
-    uint8_t ser_buf[H5FA_DBLOCK_BUF_SIZE]; /* Serialization buffer */
+    const H5FA_dblock_t *dblock = (const H5FA_dblock_t *)_thing;      /* Pointer to the object */
 
-    /* Sanity check */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
+    /* Check arguments */
     HDassert(dblock);
-    HDassert(dblock->hdr);
-
-    if(dblock->cache_info.is_dirty) {
-        uint8_t	*buf;           /* Temporary raw data buffer */
-        uint8_t *p;             /* Pointer into raw data buffer */
-        size_t	size;           /* Index block size on disk */
-        uint32_t metadata_chksum; /* Computed metadata checksum value */
+    HDassert(image_len);
 
-        /* Wrap the local buffer for serialized info */
-        if(NULL == (wb = H5WB_wrap(ser_buf, sizeof(ser_buf))))
-            H5E_THROW(H5E_CANTINIT, "can't wrap buffer")
-
-        /* Compute the size of the data block on disk */
-        if(!dblock->npages)
-            size = (size_t)dblock->size;
-        else
-            size = H5FA_DBLOCK_PREFIX_SIZE(dblock);
+    /* Set the image length size */
+    if(!dblock->npages)
+        *image_len = (size_t)dblock->size;
+    else
+        *image_len = H5FA_DBLOCK_PREFIX_SIZE(dblock);
 
-        /* Get a pointer to a buffer that's large enough for serialized info */
-        if(NULL == (buf = (uint8_t *)H5WB_actual(wb, size)))
-            H5E_THROW(H5E_CANTGET, "can't get actual buffer")
+END_FUNC(STATIC)   /* end H5FA__cache_dblock_image_len() */
 
-        /* Get temporary pointer to serialized info */
-        p = buf;
+
+/*-------------------------------------------------------------------------
+ * Function:	H5FA__cache_dblock_serialize
+ *
+ * Purpose:	Flushes a dirty object to disk.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              August 14, 2013
+ *
+ *-------------------------------------------------------------------------
+ */
+BEGIN_FUNC(STATIC, ERR,
+herr_t, SUCCEED, FAIL,
+H5FA__cache_dblock_serialize(const H5F_t *f, void *_image, size_t H5_ATTR_UNUSED len,
+    void *_thing))
 
-        /* Magic number */
-        HDmemcpy(p, H5FA_DBLOCK_MAGIC, (size_t)H5_SIZEOF_MAGIC);
-        p += H5_SIZEOF_MAGIC;
+    /* Local variables */
+    H5FA_dblock_t *dblock = (H5FA_dblock_t *)_thing;      /* Pointer to the object to serialize */
+    uint8_t *image = (uint8_t *)_image;         /* Pointer into raw data buffer */
+    uint32_t metadata_chksum; /* Computed metadata checksum value */
 
-        /* Version # */
-        *p++ = H5FA_DBLOCK_VERSION;
+    /* Check arguments */
+    HDassert(f);
+    HDassert(image);
+    HDassert(dblock);
+    HDassert(dblock->hdr);
 
-        /* Fixed array type */
-        *p++ = dblock->hdr->cparam.cls->id;
+    /* Magic number */
+    HDmemcpy(image, H5FA_DBLOCK_MAGIC, (size_t)H5_SIZEOF_MAGIC);
+    image += H5_SIZEOF_MAGIC;
 
-        /* Address of array header for array which owns this block */
-        H5F_addr_encode(f, &p, dblock->hdr->addr);
+    /* Version # */
+    *image++ = H5FA_DBLOCK_VERSION;
 
-        /* Page init flags */
-	if(dblock->npages > 0) {
-	    /* Store the 'page init' bitmasks */
-            HDmemcpy(p, dblock->dblk_page_init, dblock->dblk_page_init_size);
-            p += dblock->dblk_page_init_size;
-	} /* end if */
+    /* Fixed array type */
+    *image++ = dblock->hdr->cparam.cls->id;
 
-        /* Only encode elements if the data block is not paged */
-        if(!dblock->npages) {
-            /* Encode elements in data block */
+    /* Address of array header for array which owns this block */
+    H5F_addr_encode(f, &image, dblock->hdr->addr);
 
-            /* Convert from native elements in memory into raw elements on disk */
-            H5_CHECK_OVERFLOW(dblock->hdr->cparam.nelmts, /* From: */hsize_t, /* To: */size_t);
-            if((dblock->hdr->cparam.cls->encode)(p, dblock->elmts, (size_t)dblock->hdr->cparam.nelmts, dblock->hdr->cb_ctx) < 0)
-                H5E_THROW(H5E_CANTENCODE, "can't encode fixed array data elements")
-            p += (dblock->hdr->cparam.nelmts * dblock->hdr->cparam.raw_elmt_size);
-        } /* end if */
+    /* Page init flags */
+    if(dblock->npages > 0) {
+        /* Store the 'page init' bitmasks */
+        HDmemcpy(image, dblock->dblk_page_init, dblock->dblk_page_init_size);
+        image += dblock->dblk_page_init_size;
+    } /* end if */
 
-        /* Compute metadata checksum */
-        metadata_chksum = H5_checksum_metadata(buf, (size_t)(p - buf), 0);
+    /* Only encode elements if the data block is not paged */
+    if(!dblock->npages) {
+        /* Encode elements in data block */
 
-        /* Metadata checksum */
-        UINT32ENCODE(p, metadata_chksum);
+        /* Convert from native elements in memory into raw elements on disk */
+        H5_CHECK_OVERFLOW(dblock->hdr->cparam.nelmts, /* From: */hsize_t, /* To: */size_t);
+        if((dblock->hdr->cparam.cls->encode)(image, dblock->elmts, (size_t)dblock->hdr->cparam.nelmts, dblock->hdr->cb_ctx) < 0)
+            H5E_THROW(H5E_CANTENCODE, "can't encode fixed array data elements")
+        image += (dblock->hdr->cparam.nelmts * dblock->hdr->cparam.raw_elmt_size);
+    } /* end if */
 
-	/* Write the data block */
-        HDassert((size_t)(p - buf) == size);
-	if(H5F_block_write(f, H5FD_MEM_FARRAY_DBLOCK, addr, size, dxpl_id, buf) < 0)
-            H5E_THROW(H5E_WRITEERROR, "unable to save fixed array data block to disk")
+    /* Compute metadata checksum */
+    metadata_chksum = H5_checksum_metadata(_image, (size_t)(image - (uint8_t *)_image), 0);
 
-	dblock->cache_info.is_dirty = FALSE;
-    } /* end if */
+    /* Metadata checksum */
+    UINT32ENCODE(image, metadata_chksum);
 
-    if(destroy)
-        if(H5FA__cache_dblock_dest(f, dblock) < 0)
-            H5E_THROW(H5E_CANTFREE, "unable to destroy fixed array data block")
+    /* Sanity check */
+    HDassert((size_t)(image - (uint8_t *)_image) == len);
 
 CATCH
 
-    /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-	H5E_THROW(H5E_CLOSEERROR, "can't close wrapped buffer")
-
-END_FUNC(STATIC)   /* end H5FA__cache_dblock_flush() */
+END_FUNC(STATIC)   /* end H5FA__cache_dblock_serialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5FA__cache_dblock_clear
+ * Function:	H5FA__cache_dblock_free_icr
  *
- * Purpose:	Mark a fixed array data block in memory as non-dirty.
+ * Purpose:	Destroy/release an "in core representation" of a data
+ *              structure
  *
  * Return:	Non-negative on success/Negative on failure
  *
- * Programmer:	Vailin Choi
- *              Thursday, April 30, 2009
+ * Programmer:	Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              August 14, 2013
  *
  *-------------------------------------------------------------------------
  */
 BEGIN_FUNC(STATIC, ERR,
 herr_t, SUCCEED, FAIL,
-H5FA__cache_dblock_clear(H5F_t *f, H5FA_dblock_t *dblock, hbool_t destroy))
+H5FA__cache_dblock_free_icr(void *_thing))
 
-    /* Sanity check */
-    HDassert(dblock);
+    H5FA_dblock_t *dblock = (H5FA_dblock_t *)_thing;    /* Pointer to the object */
 
-    /* Reset the dirty flag */
-    dblock->cache_info.is_dirty = FALSE;
+    /* Check arguments */
+    HDassert(dblock);
 
-    if(destroy)
-        if(H5FA__cache_dblock_dest(f, dblock) < 0)
-            H5E_THROW(H5E_CANTFREE, "unable to destroy fixed array data block")
+    /* Release the fixed array data block */
+    if(H5FA__dblock_dest(dblock) < 0)
+        H5E_THROW(H5E_CANTFREE, "can't free fixed array data block")
 
 CATCH
 
-END_FUNC(STATIC)   /* end H5FA__cache_dblock_clear() */
+END_FUNC(STATIC)   /* end H5FA__cache_dblock_free_icr() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5FA__cache_dblock_size
- *
- * Purpose:	Compute the size in bytes of a fixed array data block
- *		on disk, and return it in *size_ptr.  On failure,
- *		the value of *size_ptr is undefined.
- *
+ * Function:	H5FA__cache_dblock_fsf_size
+ *
+ * Purpose:	Tell the metadata cache the actual amount of file space
+ *		to free when a dblock entry is destroyed with the free
+ *		file space block set.
+ *
+ *		This function is needed when the data block is paged, as 
+ *		the datablock header and all its pages are allocted as a
+ *		single contiguous chunk of file space, and must be 
+ *		deallocated the same way.
+ *
+ *		The size of the chunk of memory in which the dblock
+ *		header and all its pages is stored in the size field,
+ *		so we simply pass that value back to the cache.
+ *
+ *		If the datablock is not paged, then the size field of 
+ *		the cache_info contains the correct size.  However this
+ *		value will be the same as the size field, so we return
+ *		the contents of the size field to the cache in this case
+ *		as well.
+ *		
  * Return:	Non-negative on success/Negative on failure
  *
- * Programmer:	Vailin Choi
- *              Thursday, April 30, 2009
+ * Programmer:	John Mainzer
+ *              12/5/14
  *
  *-------------------------------------------------------------------------
  */
-/* ARGSUSED */
 BEGIN_FUNC(STATIC, NOERR,
 herr_t, SUCCEED, -,
-H5FA__cache_dblock_size(const H5F_t H5_ATTR_UNUSED *f, const H5FA_dblock_t *dblock,
-    size_t *size_ptr))
+H5FA__cache_dblock_fsf_size(const void *_thing, size_t *fsf_size))
 
-    /* Sanity check */
-    HDassert(f);
+    const H5FA_dblock_t *dblock = (const H5FA_dblock_t *)_thing;    /* Pointer to the object */
+
+    /* Check arguments */
     HDassert(dblock);
-    HDassert(size_ptr);
+    HDassert(dblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(dblock->cache_info.type == H5AC_FARRAY_DBLOCK);
+    HDassert(fsf_size);
 
-    /* Set size value */
-    if(!dblock->npages)
-        *size_ptr = (size_t)dblock->size;
-    else
-        *size_ptr = H5FA_DBLOCK_PREFIX_SIZE(dblock);
+    *fsf_size = dblock->size;
 
-END_FUNC(STATIC)   /* end H5FA__cache_dblock_size() */
+END_FUNC(STATIC)   /* end H5FA__cache_dblock_fsf_size() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5FA__cache_dblock_dest
+ * Function:    H5FA__cache_dblk_page_get_load_size
  *
- * Purpose:	Destroys a fixed array data block in memory.
+ * Purpose:     Compute the size of the data structure on disk.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Vailin Choi
- *              Thursday, April 30, 2009
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              August 14, 2013
  *
  *-------------------------------------------------------------------------
  */
-/* ARGSUSED */
-BEGIN_FUNC(STATIC, ERR,
-herr_t, SUCCEED, FAIL,
-H5FA__cache_dblock_dest(H5F_t *f, H5FA_dblock_t *dblock))
-
-    /* Sanity check */
-    HDassert(f);
-    HDassert(dblock);
-
-    /* Verify that data block is clean */
-    HDassert(dblock->cache_info.is_dirty == FALSE);
-
-    /* If we're going to free the space on disk, the address must be valid */
-    HDassert(!dblock->cache_info.free_file_space_on_destroy || H5F_addr_defined(dblock->cache_info.addr));
-
-    /* Check for freeing file space for fixed array data block */
-    if(dblock->cache_info.free_file_space_on_destroy) {
-        /* Sanity check address */
-        HDassert(H5F_addr_eq(dblock->addr, dblock->cache_info.addr));
+BEGIN_FUNC(STATIC, NOERR,
+herr_t, SUCCEED, -,
+H5FA__cache_dblk_page_get_load_size(const void *_udata, size_t *image_len))
 
-        /* Release the space on disk */
-        /* (Includes space for pages!) */
-        /* (XXX: Nasty usage of internal DXPL value! -QAK) */
-        if(H5MF_xfree(f, H5FD_MEM_FARRAY_DBLOCK, H5AC_dxpl_id, dblock->cache_info.addr, (hsize_t)dblock->size) < 0)
-            H5E_THROW(H5E_CANTFREE, "unable to free fixed array data block")
-    } /* end if */
+    /* Local variables */
+    const H5FA_dblk_page_cache_ud_t *udata = (const H5FA_dblk_page_cache_ud_t *)_udata;      /* User data */
 
-    /* Release the data block */
-    if(H5FA__dblock_dest(dblock) < 0)
-        H5E_THROW(H5E_CANTFREE, "can't free fixed array data block")
+    /* Check arguments */
+    HDassert(udata);
+    HDassert(udata->hdr);
+    HDassert(udata->nelmts > 0);
+    HDassert(image_len);
 
-CATCH
+    *image_len = (size_t)H5FA_DBLK_PAGE_SIZE(udata->hdr, udata->nelmts);
 
-END_FUNC(STATIC)   /* end H5FA__cache_dblock_dest() */
+END_FUNC(STATIC)   /* end H5FA__cache_dblk_page_get_load_size() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5FA__cache_dblk_page_load
+ * Function:	H5FA__cache_dblk_page_deserialize
  *
- * Purpose:	Loads a fixed array data block page from the disk.
+ * Purpose:	Loads a data structure from the disk.
  *
- * Return:	Success:	Pointer to a new fixed array data block page
+ * Return:	Success:	Pointer to a new B-tree.
  *		Failure:	NULL
  *
- * Programmer:	Vailin Choi
- *              Thursday, April 30, 2009
+ * Programmer:	Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              August 14, 2013
  *
  *-------------------------------------------------------------------------
  */
 BEGIN_FUNC(STATIC, ERR,
-H5FA_dblk_page_t *, NULL, NULL,
-H5FA__cache_dblk_page_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata))
+void *, NULL, NULL,
+H5FA__cache_dblk_page_deserialize(const void *_image, size_t len,
+    void *_udata, hbool_t H5_ATTR_UNUSED *dirty))
 
     /* Local variables */
     H5FA_dblk_page_t	*dblk_page = NULL; /* Data block page info */
     H5FA_dblk_page_cache_ud_t *udata = (H5FA_dblk_page_cache_ud_t *)_udata; /* User data for loading data block page */
-    size_t		size;           /* Data block page size */
-    H5WB_t              *wb = NULL;     /* Wrapped buffer for data block page data */
-    uint8_t             dblk_page_buf[H5FA_DBLK_PAGE_BUF_SIZE]; /* Buffer for data block page */
-    uint8_t		*buf;           /* Pointer to data block page buffer */
-    const uint8_t	*p;             /* Pointer into raw data buffer */
+    const uint8_t	*image = (const uint8_t *)_image;       /* Pointer into raw data buffer */
     uint32_t            stored_chksum;  /* Stored metadata checksum value */
     uint32_t            computed_chksum; /* Computed metadata checksum value */
 
     /* Sanity check */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
-    HDassert(udata && udata->hdr && udata->nelmts > 0);
+    HDassert(udata);
+    HDassert(udata->hdr);
+    HDassert(udata->nelmts > 0);
+    HDassert(H5F_addr_defined(udata->dblk_page_addr));
 
     /* Allocate the fixed array data block page */
     if(NULL == (dblk_page = H5FA__dblk_page_alloc(udata->hdr, udata->nelmts)))
 	H5E_THROW(H5E_CANTALLOC, "memory allocation failed for fixed array data block page")
 
     /* Set the fixed array data block's information */
-    dblk_page->addr = addr;
-
-    /* Wrap the local buffer for serialized info */
-    if(NULL == (wb = H5WB_wrap(dblk_page_buf, sizeof(dblk_page_buf))))
-	H5E_THROW(H5E_CANTINIT, "can't wrap buffer")
-
-    /* Compute the size of the fixed array data block page on disk */
-    size = H5FA_DBLK_PAGE_SIZE(udata->hdr, udata->nelmts);
-
-    /* Get a pointer to a buffer that's large enough for serialized info */
-    if(NULL == (buf = (uint8_t *)H5WB_actual(wb, size)))
-	H5E_THROW(H5E_CANTGET, "can't get actual buffer")
-
-    /* Read data block page from disk */
-    if(H5F_block_read(f, H5FD_MEM_FARRAY_DBLK_PAGE, addr, size, dxpl_id, buf) < 0)
-	H5E_THROW(H5E_READERROR, "can't read fixed array data block page")
-
-    /* Get temporary pointer to serialized header */
-    p = buf;
+    dblk_page->addr = udata->dblk_page_addr;
 
     /* Internal information */
 
     /* Decode elements in data block page */
     /* Convert from raw elements on disk into native elements in memory */
-    if((udata->hdr->cparam.cls->decode)(p, dblk_page->elmts, udata->nelmts, udata->hdr->cb_ctx) < 0)
+    if((udata->hdr->cparam.cls->decode)(image, dblk_page->elmts, udata->nelmts, udata->hdr->cb_ctx) < 0)
         H5E_THROW(H5E_CANTDECODE, "can't decode fixed array data elements")
-    p += (udata->nelmts * udata->hdr->cparam.raw_elmt_size);
+    image += (udata->nelmts * udata->hdr->cparam.raw_elmt_size);
 
     /* Sanity check */
     /* (allow for checksum not decoded yet) */
-    HDassert((size_t)(p - buf) == (size - H5FA_SIZEOF_CHKSUM));
+    HDassert((size_t)(image - (const uint8_t *)_image) == (len - H5FA_SIZEOF_CHKSUM));
 
     /* Set the data block page's size */
-    dblk_page->size = size;
+    dblk_page->size = len;
 
     /* Compute checksum on data block */
-    computed_chksum = H5_checksum_metadata(buf, (size_t)(p - buf), 0);
+    computed_chksum = H5_checksum_metadata(_image, (size_t)(image - (const uint8_t *)_image), 0);
 
     /* Metadata checksum */
-    UINT32DECODE(p, stored_chksum);
+    UINT32DECODE(image, stored_chksum);
 
     /* Sanity check */
-    HDassert((size_t)(p - buf) == dblk_page->size);
+    HDassert((size_t)(image - (const uint8_t *)_image) == dblk_page->size);
 
     /* Verify checksum */
     if(stored_chksum != computed_chksum)
@@ -930,192 +893,122 @@ H5FA__cache_dblk_page_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata))
 CATCH
 
     /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-	H5E_THROW(H5E_CLOSEERROR, "can't close wrapped buffer")
     if(!ret_value)
         if(dblk_page && H5FA__dblk_page_dest(dblk_page) < 0)
             H5E_THROW(H5E_CANTFREE, "unable to destroy fixed array data block page")
 
-END_FUNC(STATIC)   /* end H5FA__cache_dblk_page_load() */
+END_FUNC(STATIC)   /* end H5FA__cache_dblk_page_deserialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5FA__cache_dblk_page_flush
+ * Function:    H5FA__cache_dblk_page_image_len
  *
- * Purpose:	Flushes a dirty fixed array data block page to disk.
+ * Purpose:     Compute the size of the data structure on disk.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Vailin Choi
- *              Thursday, April 30, 2009
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              August 14, 2013
  *
  *-------------------------------------------------------------------------
  */
-BEGIN_FUNC(STATIC, ERR,
-herr_t, SUCCEED, FAIL,
-H5FA__cache_dblk_page_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr,
-    H5FA_dblk_page_t *dblk_page, unsigned H5_ATTR_UNUSED * flags_ptr))
+BEGIN_FUNC(STATIC, NOERR,
+herr_t, SUCCEED, -,
+H5FA__cache_dblk_page_image_len(const void *_thing, size_t *image_len,
+    hbool_t H5_ATTR_UNUSED *compressed_ptr, size_t H5_ATTR_UNUSED *compressed_image_len_ptr))
 
     /* Local variables */
-    H5WB_t *wb = NULL;                  /* Wrapped buffer for serializing data */
-    uint8_t ser_buf[H5FA_DBLK_PAGE_BUF_SIZE]; /* Serialization buffer */
+    const H5FA_dblk_page_t *dblk_page = (const H5FA_dblk_page_t *)_thing;      /* Pointer to the object */
 
-    /* Sanity check */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
+    /* Check arguments */
     HDassert(dblk_page);
-    HDassert(dblk_page->hdr);
-
-    if(dblk_page->cache_info.is_dirty) {
-        uint8_t	*buf;           /* Temporary raw data buffer */
-        uint8_t *p;             /* Pointer into raw data buffer */
-        size_t	size;           /* Index block size on disk */
-        uint32_t metadata_chksum; /* Computed metadata checksum value */
-
-        /* Wrap the local buffer for serialized info */
-        if(NULL == (wb = H5WB_wrap(ser_buf, sizeof(ser_buf))))
-            H5E_THROW(H5E_CANTINIT, "can't wrap buffer")
-
-        /* Compute the size of the data block on disk */
-        size = dblk_page->size;
-
-        /* Get a pointer to a buffer that's large enough for serialized info */
-        if(NULL == (buf = (uint8_t *)H5WB_actual(wb, size)))
-            H5E_THROW(H5E_CANTGET, "can't get actual buffer")
-
-        /* Get temporary pointer to serialized info */
-        p = buf;
-
-        /* Internal information */
-
-        /* Encode elements in data block page */
-
-        /* Convert from native elements in memory into raw elements on disk */
-        if((dblk_page->hdr->cparam.cls->encode)(p, dblk_page->elmts, dblk_page->nelmts, dblk_page->hdr->cb_ctx) < 0)
-            H5E_THROW(H5E_CANTENCODE, "can't encode fixed array data elements")
-        p += (dblk_page->nelmts * dblk_page->hdr->cparam.raw_elmt_size);
-
-        /* Compute metadata checksum */
-        metadata_chksum = H5_checksum_metadata(buf, (size_t)(p - buf), 0);
-
-        /* Metadata checksum */
-        UINT32ENCODE(p, metadata_chksum);
-
-	/* Write the data block */
-        HDassert((size_t)(p - buf) == size);
-	if(H5F_block_write(f, H5FD_MEM_FARRAY_DBLK_PAGE, addr, size, dxpl_id, buf) < 0)
-            H5E_THROW(H5E_WRITEERROR, "unable to save fixed array data block page to disk")
-
-	dblk_page->cache_info.is_dirty = FALSE;
-    } /* end if */
-
-    if(destroy)
-        if(H5FA__cache_dblk_page_dest(f, dblk_page) < 0)
-            H5E_THROW(H5E_CANTFREE, "unable to destroy fixed array data block page")
+    HDassert(image_len);
 
-CATCH
-
-    /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-	H5E_THROW(H5E_CLOSEERROR, "can't close wrapped buffer")
+    /* Set the image length size */
+    *image_len = dblk_page->size; 
 
-END_FUNC(STATIC)   /* end H5FA__cache_dblk_page_flush() */
+END_FUNC(STATIC)   /* end H5FA__cache_dblk_page_image_len() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5FA__cache_dblk_page_clear
+ * Function:	H5FA__cache_dblk_page_serialize
  *
- * Purpose:	Mark a fixed array data block page in memory as non-dirty.
+ * Purpose:	Flushes a dirty object to disk.
  *
  * Return:	Non-negative on success/Negative on failure
  *
- * Programmer:	Vailin Choi
- *              Thursday, April 30, 2009
+ * Programmer:	Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              August 14, 2013
  *
  *-------------------------------------------------------------------------
  */
 BEGIN_FUNC(STATIC, ERR,
 herr_t, SUCCEED, FAIL,
-H5FA__cache_dblk_page_clear(H5F_t *f, H5FA_dblk_page_t *dblk_page, hbool_t destroy))
+H5FA__cache_dblk_page_serialize(const H5F_t *f, void *_image, size_t H5_ATTR_UNUSED len,
+    void *_thing))
+
+    /* Local variables */
+    H5FA_dblk_page_t *dblk_page = (H5FA_dblk_page_t *)_thing;      /* Pointer to the object to serialize */
+    uint8_t *image = (uint8_t *)_image;         /* Pointer into raw data buffer */
+    uint32_t metadata_chksum;   /* Computed metadata checksum value */
 
     /* Sanity check */
+    HDassert(f);
+    HDassert(image);
     HDassert(dblk_page);
+    HDassert(dblk_page->hdr);
 
-    /* Reset the dirty flag */
-    dblk_page->cache_info.is_dirty = FALSE;
+    /* Internal information */
 
-    if(destroy)
-        if(H5FA__cache_dblk_page_dest(f, dblk_page) < 0)
-            H5E_THROW(H5E_CANTFREE, "unable to destroy fixed array data block page")
+    /* Encode elements in data block page */
 
-CATCH
+    /* Convert from native elements in memory into raw elements on disk */
+    if((dblk_page->hdr->cparam.cls->encode)(image, dblk_page->elmts, dblk_page->nelmts, dblk_page->hdr->cb_ctx) < 0)
+        H5E_THROW(H5E_CANTENCODE, "can't encode fixed array data elements")
+    image += (dblk_page->nelmts * dblk_page->hdr->cparam.raw_elmt_size);
 
-END_FUNC(STATIC)   /* end H5FA__cache_dblk_page_clear() */
+    /* Compute metadata checksum */
+    metadata_chksum = H5_checksum_metadata(_image, (size_t)(image - (uint8_t *)_image), 0);
 
-
-/*-------------------------------------------------------------------------
- * Function:	H5FA__cache_dblk_page_size
- *
- * Purpose:	Compute the size in bytes of a fixed array data block page
- *		on disk, and return it in *size_ptr.  On failure,
- *		the value of *size_ptr is undefined.
- *
- * Return:	Non-negative on success/Negative on failure
- *
- * Programmer:	Vailin Choi
- *              Thursday, April 30, 2009
- *
- *-------------------------------------------------------------------------
- */
-/* ARGSUSED */
-BEGIN_FUNC(STATIC, NOERR,
-herr_t, SUCCEED, -,
-H5FA__cache_dblk_page_size(const H5F_t H5_ATTR_UNUSED *f, const H5FA_dblk_page_t *dblk_page,
-    size_t *size_ptr))
+    /* Metadata checksum */
+    UINT32ENCODE(image, metadata_chksum);
 
     /* Sanity check */
-    HDassert(f);
-    HDassert(dblk_page);
-    HDassert(size_ptr);
+    HDassert((size_t)(image - (uint8_t *)_image) == len);
 
-    /* Set size value */
-    *size_ptr = dblk_page->size;
+CATCH
 
-END_FUNC(STATIC)   /* end H5FA__cache_dblk_page_size() */
+END_FUNC(STATIC)   /* end H5FA__cache_dblk_page_serialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5FA__cache_dblk_page_dest
- *
- * Purpose:	Destroys a fixed array data block page in memory.
+ * Function:	H5FA__cache_dblk_page_free_icr
  *
- * Note:	Does _not_ free the space for the page on disk, that is
- *              handled through the data block that "owns" the page.
+ * Purpose:	Destroy/release an "in core representation" of a data
+ *              structure
  *
  * Return:	Non-negative on success/Negative on failure
  *
- * Programmer:	Vailin Choi
- *              Thursday, April 30, 2009
+ * Programmer:	Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              August 14, 2013
  *
  *-------------------------------------------------------------------------
  */
-/* ARGSUSED */
 BEGIN_FUNC(STATIC, ERR,
 herr_t, SUCCEED, FAIL,
-H5FA__cache_dblk_page_dest(H5F_t H5_ATTR_UNUSED *f, H5FA_dblk_page_t *dblk_page))
+H5FA__cache_dblk_page_free_icr(void *thing))
 
-    /* Sanity check */
-    HDassert(f);
-    HDassert(dblk_page);
-
-    /* Verify that data block page is clean */
-    HDassert(dblk_page->cache_info.is_dirty == FALSE);
+    /* Check arguments */
+    HDassert(thing);
 
-    /* Release the data block page */
-    if(H5FA__dblk_page_dest(dblk_page) < 0)
+    /* Release the fixed array data block page */
+    if(H5FA__dblk_page_dest((H5FA_dblk_page_t *)thing) < 0)
         H5E_THROW(H5E_CANTFREE, "can't free fixed array data block page")
 
 CATCH
 
-END_FUNC(STATIC)   /* end H5FA__cache_dblk_page_dest() */
+END_FUNC(STATIC)   /* end H5FA__cache_dblk_page_free_icr() */
 
diff --git a/src/H5FAdbg.c b/src/H5FAdbg.c
index d5239d3..6a84fc9 100644
--- a/src/H5FAdbg.c
+++ b/src/H5FAdbg.c
@@ -117,7 +117,7 @@ H5FA__hdr_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE *stream, int indent,
     } /* end if */
 
     /* Load the fixed array header */
-    if(NULL == (hdr = H5FA__hdr_protect(f, dxpl_id, addr, dbg_ctx, H5AC_READ)))
+    if(NULL == (hdr = H5FA__hdr_protect(f, dxpl_id, addr, dbg_ctx, H5AC__READ_ONLY_FLAG)))
 	H5E_THROW(H5E_CANTPROTECT, "unable to load fixed array header")
 
     /* Print opening message */
@@ -198,11 +198,11 @@ H5FA__dblock_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE *stream, int inde
     } /* end if */
 
     /* Load the fixed array header */
-    if(NULL == (hdr = H5FA__hdr_protect(f, dxpl_id, hdr_addr, dbg_ctx, H5AC_READ)))
+    if(NULL == (hdr = H5FA__hdr_protect(f, dxpl_id, hdr_addr, dbg_ctx, H5AC__READ_ONLY_FLAG)))
 	H5E_THROW(H5E_CANTPROTECT, "unable to load fixed array header")
 
     /* Protect data block */
-    if(NULL == (dblock = H5FA__dblock_protect(hdr, dxpl_id, addr, H5AC_READ)))
+    if(NULL == (dblock = H5FA__dblock_protect(hdr, dxpl_id, addr, H5AC__READ_ONLY_FLAG)))
         H5E_THROW(H5E_CANTPROTECT, "unable to protect fixed array data block, address = %llu", (unsigned long long)addr)
 
     /* Print opening message */
@@ -246,7 +246,7 @@ H5FA__dblock_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE *stream, int inde
 		if(((page_idx + 1) == dblock->npages) && (nelmts_left = hdr->cparam.nelmts % dblock->dblk_page_nelmts))
 		    dblk_page_nelmts = (size_t)nelmts_left;
 
-		if(NULL == (dblk_page = H5FA__dblk_page_protect(hdr, dxpl_id, dblk_page_addr, dblk_page_nelmts, H5AC_READ)))
+		if(NULL == (dblk_page = H5FA__dblk_page_protect(hdr, dxpl_id, dblk_page_addr, dblk_page_nelmts, H5AC__READ_ONLY_FLAG)))
 		    H5E_THROW(H5E_CANTPROTECT, "unable to protect fixed array data block page, address = %llu", (unsigned long long)dblk_page_addr)
 
 		HDfprintf(stream, "%*sElements in page %Zu:\n", indent, "", page_idx);
diff --git a/src/H5FAdblkpage.c b/src/H5FAdblkpage.c
index 1f6b706..e1ea3ac 100644
--- a/src/H5FAdblkpage.c
+++ b/src/H5FAdblkpage.c
@@ -207,7 +207,7 @@ END_FUNC(PKG)   /* end H5FA__dblk_page_create() */
 BEGIN_FUNC(PKG, ERR,
 H5FA_dblk_page_t *, NULL, NULL,
 H5FA__dblk_page_protect(H5FA_hdr_t *hdr, hid_t dxpl_id, haddr_t dblk_page_addr,
-    size_t dblk_page_nelmts, H5AC_protect_t rw))
+    size_t dblk_page_nelmts, unsigned flags))
 
     /* Local variables */
     H5FA_dblk_page_cache_ud_t udata;      /* Information needed for loading data block page */
@@ -220,12 +220,16 @@ HDfprintf(stderr, "%s: Called\n", FUNC);
     HDassert(hdr);
     HDassert(H5F_addr_defined(dblk_page_addr));
 
+    /* only the H5AC__READ_ONLY_FLAG is permitted */
+    HDassert((flags & (unsigned)(~H5AC__READ_ONLY_FLAG)) == 0);
+
     /* Set up user data */
     udata.hdr = hdr;
     udata.nelmts = dblk_page_nelmts;
+    udata.dblk_page_addr = dblk_page_addr;
 
     /* Protect the data block page */
-    if(NULL == (ret_value = (H5FA_dblk_page_t *)H5AC_protect(hdr->f, dxpl_id, H5AC_FARRAY_DBLK_PAGE, dblk_page_addr, &udata, rw)))
+    if(NULL == (ret_value = (H5FA_dblk_page_t *)H5AC_protect(hdr->f, dxpl_id, H5AC_FARRAY_DBLK_PAGE, dblk_page_addr, &udata, flags)))
         H5E_THROW(H5E_CANTPROTECT, "unable to protect fixed array data block page, address = %llu", (unsigned long long)dblk_page_addr)
 
 CATCH
diff --git a/src/H5FAdblock.c b/src/H5FAdblock.c
index e6e0e74..42dafeb 100644
--- a/src/H5FAdblock.c
+++ b/src/H5FAdblock.c
@@ -263,7 +263,7 @@ END_FUNC(PKG)   /* end H5FA__dblock_create() */
 BEGIN_FUNC(PKG, ERR,
 H5FA_dblock_t *, NULL, NULL,
 H5FA__dblock_protect(H5FA_hdr_t *hdr, hid_t dxpl_id, haddr_t dblk_addr,
-    H5AC_protect_t rw))
+    unsigned flags))
 
     /* Local variables */
     H5FA_dblock_cache_ud_t udata;      /* Information needed for loading data block */
@@ -276,11 +276,15 @@ HDfprintf(stderr, "%s: Called\n", FUNC);
     HDassert(hdr);
     HDassert(H5F_addr_defined(dblk_addr));
 
+    /* only the H5AC__READ_ONLY_FLAG flag is permitted */
+    HDassert((flags & (unsigned)(~H5AC__READ_ONLY_FLAG)) == 0);
+
     /* Set up user data */
     udata.hdr = hdr;
+    udata.dblk_addr = dblk_addr;
 
     /* Protect the data block */
-    if(NULL == (ret_value = (H5FA_dblock_t *)H5AC_protect(hdr->f, dxpl_id, H5AC_FARRAY_DBLOCK, dblk_addr, &udata, rw)))
+    if(NULL == (ret_value = (H5FA_dblock_t *)H5AC_protect(hdr->f, dxpl_id, H5AC_FARRAY_DBLOCK, dblk_addr, &udata, flags)))
         H5E_THROW(H5E_CANTPROTECT, "unable to protect fixed array data block, address = %llu", (unsigned long long)dblk_addr)
 
 CATCH
@@ -350,7 +354,7 @@ HDfprintf(stderr, "%s: Called\n", FUNC);
     HDassert(H5F_addr_defined(dblk_addr));
 
     /* Protect data block */
-    if(NULL == (dblock = H5FA__dblock_protect(hdr, dxpl_id, dblk_addr, H5AC_WRITE)))
+    if(NULL == (dblock = H5FA__dblock_protect(hdr, dxpl_id, dblk_addr, H5AC__NO_FLAGS_SET)))
         H5E_THROW(H5E_CANTPROTECT, "unable to protect fixed array data block, address = %llu", (unsigned long long)dblk_addr)
 
     /* Check if data block is paged */
diff --git a/src/H5FAhdr.c b/src/H5FAhdr.c
index 23c20bc..9083a52 100644
--- a/src/H5FAhdr.c
+++ b/src/H5FAhdr.c
@@ -408,16 +408,25 @@ END_FUNC(PKG)   /* end H5FA__hdr_modified() */
 BEGIN_FUNC(PKG, ERR,
 H5FA_hdr_t *, NULL, NULL,
 H5FA__hdr_protect(H5F_t *f, hid_t dxpl_id, haddr_t fa_addr, void *ctx_udata,
-    H5AC_protect_t rw))
+    unsigned flags))
 
     /* Local variables */
+    H5FA_hdr_cache_ud_t udata;  /* User data for cache callbacks */
 
     /* Sanity check */
     HDassert(f);
     HDassert(H5F_addr_defined(fa_addr));
 
+    /* only the H5AC__READ_ONLY_FLAG is permitted */
+    HDassert((flags & (unsigned)(~H5AC__READ_ONLY_FLAG)) == 0);
+
+    /* Set up user data for cache callbacks */
+    udata.f = f;
+    udata.addr = fa_addr;
+    udata.ctx_udata = ctx_udata;
+
     /* Protect the header */
-    if(NULL == (ret_value = (H5FA_hdr_t *)H5AC_protect(f, dxpl_id, H5AC_FARRAY_HDR, fa_addr, ctx_udata, rw)))
+    if(NULL == (ret_value = (H5FA_hdr_t *)H5AC_protect(f, dxpl_id, H5AC_FARRAY_HDR, fa_addr, &udata, flags)))
         H5E_THROW(H5E_CANTPROTECT, "unable to protect fixed array header, address = %llu", (unsigned long long)fa_addr)
 
 CATCH
diff --git a/src/H5FApkg.h b/src/H5FApkg.h
index e7993a6..bed9c83 100644
--- a/src/H5FApkg.h
+++ b/src/H5FApkg.h
@@ -206,15 +206,24 @@ struct H5FA_t {
 
 /* Metadata cache callback user data types */
 
+/* Info needed for loading header */
+typedef struct H5FA_hdr_cache_ud_t {
+    H5F_t      *f;              /* Pointer to file for fixed array */
+    haddr_t    addr;            /* Address of header on disk */
+    void       *ctx_udata;      /* User context for class */
+} H5FA_hdr_cache_ud_t;
+
 /* Info needed for loading data block */
 typedef struct H5FA_dblock_cache_ud_t {
     H5FA_hdr_t *hdr;            /* Shared fixed array information */
+    haddr_t     dblk_addr;      /* Address of data block on disk */
 } H5FA_dblock_cache_ud_t;
 
 /* Info needed for loading data block page */
 typedef struct H5FA_dblk_page_cache_ud_t {
     H5FA_hdr_t *hdr;            /* Shared fixed array information */
     size_t      nelmts;         /* Number of elements in data block page */
+    haddr_t     dblk_page_addr; /* Address of data block page on disk */
 } H5FA_dblk_page_cache_ud_t;
 
 
@@ -254,7 +263,7 @@ H5_DLL herr_t H5FA__hdr_fuse_incr(H5FA_hdr_t *hdr);
 H5_DLL size_t H5FA__hdr_fuse_decr(H5FA_hdr_t *hdr);
 H5_DLL herr_t H5FA__hdr_modified(H5FA_hdr_t *hdr);
 H5_DLL H5FA_hdr_t *H5FA__hdr_protect(H5F_t *f, hid_t dxpl_id, haddr_t fa_addr,
-    void *ctx_udata, H5AC_protect_t rw);
+    void *ctx_udata, unsigned flags);
 H5_DLL herr_t H5FA__hdr_unprotect(H5FA_hdr_t *hdr, hid_t dxpl_id, unsigned cache_flags);
 H5_DLL herr_t H5FA__hdr_delete(H5FA_hdr_t *hdr, hid_t dxpl_id);
 H5_DLL herr_t H5FA__hdr_dest(H5FA_hdr_t *hdr);
@@ -264,7 +273,7 @@ H5_DLL H5FA_dblock_t *H5FA__dblock_alloc(H5FA_hdr_t *hdr);
 H5_DLL haddr_t H5FA__dblock_create(H5FA_hdr_t *hdr, hid_t dxpl_id, hbool_t *hdr_dirty);
 H5_DLL unsigned H5FA__dblock_sblk_idx(const H5FA_hdr_t *hdr, hsize_t idx);
 H5_DLL H5FA_dblock_t *H5FA__dblock_protect(H5FA_hdr_t *hdr, hid_t dxpl_id,
-    haddr_t dblk_addr, H5AC_protect_t rw);
+    haddr_t dblk_addr, unsigned flags);
 H5_DLL herr_t H5FA__dblock_unprotect(H5FA_dblock_t *dblock, hid_t dxpl_id,
     unsigned cache_flags);
 H5_DLL herr_t H5FA__dblock_delete(H5FA_hdr_t *hdr, hid_t dxpl_id,
@@ -276,7 +285,7 @@ H5_DLL herr_t H5FA__dblk_page_create(H5FA_hdr_t *hdr, hid_t dxpl_id,
     haddr_t addr, size_t nelmts);
 H5_DLL H5FA_dblk_page_t *H5FA__dblk_page_alloc(H5FA_hdr_t *hdr, size_t nelmts);
 H5_DLL H5FA_dblk_page_t *H5FA__dblk_page_protect(H5FA_hdr_t *hdr, hid_t dxpl_id,
-    haddr_t dblk_page_addr, size_t dblk_page_nelmts, H5AC_protect_t rw);
+    haddr_t dblk_page_addr, size_t dblk_page_nelmts, unsigned flags);
 H5_DLL herr_t H5FA__dblk_page_unprotect(H5FA_dblk_page_t *dblk_page,
     hid_t dxpl_id, unsigned cache_flags);
 H5_DLL herr_t H5FA__dblk_page_dest(H5FA_dblk_page_t *dblk_page);
diff --git a/src/H5FDfamily.c b/src/H5FDfamily.c
index d993ad0..9edbc72 100644
--- a/src/H5FDfamily.c
+++ b/src/H5FDfamily.c
@@ -905,7 +905,7 @@ H5FD_family_query(const H5FD_t * _file, unsigned long *flags /* out */)
 
         /* Check for flags that are set by h5repart */
         if(file && file->repart_members)
-            *flags |= H5FD_FEAT_DIRTY_SBLK_LOAD; /* Mark the superblock dirty when it is loaded (so the family member sizes are rewritten) */
+            *flags |= H5FD_FEAT_DIRTY_DRVRINFO_LOAD; /* Mark the superblock dirty when it is loaded (so the family member sizes are rewritten) */
     } /* end if */
 
     FUNC_LEAVE_NOAPI(SUCCEED)
diff --git a/src/H5FDpublic.h b/src/H5FDpublic.h
index df5d5cf..58066cc 100644
--- a/src/H5FDpublic.h
+++ b/src/H5FDpublic.h
@@ -198,12 +198,12 @@ typedef enum H5F_mem_t	H5FD_mem_t;
      */
 #define H5FD_FEAT_IGNORE_DRVRINFO       0x00000020
     /*
-     * Defining the H5FD_FEAT_DIRTY_SBLK_LOAD for a VFL driver means that
-     * the library will mark the superblock dirty when the file is opened
+     * Defining the H5FD_FEAT_DIRTY_DRVRINFO_LOAD for a VFL driver means that
+     * the library will mark the driver info dirty when the file is opened
      * R/W.  This will cause the driver info to be re-encoded when the file
      * is flushed/closed.
      */
-#define H5FD_FEAT_DIRTY_SBLK_LOAD       0x00000040
+#define H5FD_FEAT_DIRTY_DRVRINFO_LOAD   0x00000040
     /*
      * Defining the H5FD_FEAT_POSIX_COMPAT_HANDLE for a VFL driver means that
      * the handle for the VFD (returned with the 'get_handle' callback) is
diff --git a/src/H5FS.c b/src/H5FS.c
index 42ea070..182ac05 100644
--- a/src/H5FS.c
+++ b/src/H5FS.c
@@ -216,7 +216,7 @@ HDfprintf(stderr, "%s: Opening free space manager, fs_addr = %a, nclasses = %Zu\
     cache_udata.addr = fs_addr;
 
     /* Protect the free space header */
-    if(NULL == (fspace = (H5FS_t *)H5AC_protect(f, dxpl_id, H5AC_FSPACE_HDR, fs_addr, &cache_udata, H5AC_READ)))
+    if(NULL == (fspace = (H5FS_t *)H5AC_protect(f, dxpl_id, H5AC_FSPACE_HDR, fs_addr, &cache_udata, H5AC__READ_ONLY_FLAG)))
         HGOTO_ERROR(H5E_FSPACE, H5E_CANTPROTECT, NULL, "unable to load free space header")
 #ifdef H5FS_DEBUG
 HDfprintf(stderr, "%s: fspace->sect_addr = %a\n", FUNC, fspace->sect_addr);
@@ -329,7 +329,7 @@ HDfprintf(stderr, "%s: Deleting free space manager, fs_addr = %a\n", FUNC, fs_ad
 #endif /* H5FS_DEBUG */
 
     /* Protect the free space header */
-    if(NULL == (fspace = (H5FS_t *)H5AC_protect(f, dxpl_id, H5AC_FSPACE_HDR, fs_addr, &cache_udata, H5AC_WRITE)))
+    if(NULL == (fspace = (H5FS_t *)H5AC_protect(f, dxpl_id, H5AC_FSPACE_HDR, fs_addr, &cache_udata, H5AC__NO_FLAGS_SET)))
         HGOTO_ERROR(H5E_FSPACE, H5E_CANTPROTECT, FAIL, "unable to protect free space header")
 
     /* Sanity check */
@@ -361,8 +361,19 @@ HDfprintf(stderr, "%s: Expunging free space section info from cache\n", FUNC);
 #endif /* H5FS_DEBUG */
             /* Evict the free space section info from the metadata cache */
             /* (Free file space) */
-            if(H5AC_expunge_entry(f, dxpl_id, H5AC_FSPACE_SINFO, fspace->sect_addr, H5AC__FREE_FILE_SPACE_FLAG) < 0)
-                HGOTO_ERROR(H5E_HEAP, H5E_CANTREMOVE, FAIL, "unable to remove free space section info from cache")
+            {
+                unsigned cache_flags = H5AC__NO_FLAGS_SET;
+
+                /* if the indirect block is in real file space, tell
+                 * the cache to free its file space.
+                 */
+                if (!H5F_IS_TMP_ADDR(f, fspace->sect_addr))
+                    cache_flags |= H5AC__FREE_FILE_SPACE_FLAG;
+
+                if(H5AC_expunge_entry(f, dxpl_id, H5AC_FSPACE_SINFO, fspace->sect_addr, cache_flags) < 0)
+                    HGOTO_ERROR(H5E_HEAP, H5E_CANTREMOVE, FAIL, "unable to remove free space section info from cache")
+            }
+
 #ifdef H5FS_DEBUG
 HDfprintf(stderr, "%s: Done expunging free space section info from cache\n", FUNC);
 #endif /* H5FS_DEBUG */
@@ -938,7 +949,7 @@ H5FS_free(H5F_t *f, H5FS_t *fspace, hid_t dxpl_id)
             cache_udata.f = f;
             cache_udata.dxpl_id = dxpl_id;
             cache_udata.fspace = fspace;
-	    if(NULL == (fspace->sinfo = (H5FS_sinfo_t *)H5AC_protect(f, dxpl_id, H5AC_FSPACE_SINFO, fspace->sect_addr, &cache_udata, H5AC_READ)))
+	    if(NULL == (fspace->sinfo = (H5FS_sinfo_t *)H5AC_protect(f, dxpl_id, H5AC_FSPACE_SINFO, fspace->sect_addr, &cache_udata, H5AC__READ_ONLY_FLAG)))
 		HGOTO_ERROR(H5E_FSPACE, H5E_CANTPROTECT, FAIL, "unable to protect free space section info")
 
 	    /* Unload and release ownership of the free-space manager section info */
@@ -979,7 +990,7 @@ H5FS_free(H5F_t *f, H5FS_t *fspace, hid_t dxpl_id)
             cache_udata.nclasses = 0;
             cache_udata.classes = NULL;
             cache_udata.cls_init_udata = NULL;
-	    if(NULL == (fspace = (H5FS_t *)H5AC_protect(f, dxpl_id, H5AC_FSPACE_HDR, fspace->addr, &cache_udata, H5AC_READ)))
+	    if(NULL == (fspace = (H5FS_t *)H5AC_protect(f, dxpl_id, H5AC_FSPACE_HDR, fspace->addr, &cache_udata, H5AC__READ_ONLY_FLAG)))
 		HGOTO_ERROR(H5E_FSPACE, H5E_CANTPROTECT, FAIL, "unable to protect free space section info")
 
 	    /* Unpin the free-space manager header */
diff --git a/src/H5FScache.c b/src/H5FScache.c
index 461af99..25a9c5e 100644
--- a/src/H5FScache.c
+++ b/src/H5FScache.c
@@ -49,9 +49,6 @@
 #define H5FS_HDR_VERSION        0               /* Header */
 #define H5FS_SINFO_VERSION      0               /* Serialized sections */
 
-/* Size of stack buffer for serialized headers */
-#define H5FS_HDR_BUF_SIZE               256
-
 
 /******************/
 /* Local Typedefs */
@@ -60,7 +57,7 @@
 /* User data for skip list iterator callback for iterating over section size nodes when syncing */
 typedef struct {
     H5FS_sinfo_t *sinfo;        /* Free space section info */
-    uint8_t **p;                /* Pointer to address of buffer pointer to serialize with */
+    uint8_t **image;            /* Pointer to address of buffer pointer to serialize with */
     unsigned sect_cnt_size;     /* # of bytes to encode section size counts in */
 } H5FS_iter_ud_t;
 
@@ -75,20 +72,35 @@ typedef struct {
 /********************/
 
 /* Section info routines */
-static herr_t H5FS_sinfo_serialize_sect_cb(void *_item, void H5_ATTR_UNUSED *key, void *_udata);
-static herr_t H5FS_sinfo_serialize_node_cb(void *_item, void H5_ATTR_UNUSED *key, void *_udata);
+static herr_t H5FS__sinfo_serialize_sect_cb(void *_item, void H5_ATTR_UNUSED *key, void *_udata);
+static herr_t H5FS__sinfo_serialize_node_cb(void *_item, void H5_ATTR_UNUSED *key, void *_udata);
 
 /* Metadata cache callbacks */
-static H5FS_t *H5FS_cache_hdr_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata);
-static herr_t H5FS_cache_hdr_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5FS_t *fspace, unsigned H5_ATTR_UNUSED * flags_ptr);
-static herr_t H5FS_cache_hdr_dest(H5F_t *f, H5FS_t *fspace);
-static herr_t H5FS_cache_hdr_clear(H5F_t *f, H5FS_t *fspace, hbool_t destroy);
-static herr_t H5FS_cache_hdr_size(const H5F_t *f, const H5FS_t *fspace, size_t *size_ptr);
-static H5FS_sinfo_t *H5FS_cache_sinfo_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata);
-static herr_t H5FS_cache_sinfo_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5FS_sinfo_t *sinfo, unsigned H5_ATTR_UNUSED * flags_ptr);
-static herr_t H5FS_cache_sinfo_dest(H5F_t *f, H5FS_sinfo_t *sinfo);
-static herr_t H5FS_cache_sinfo_clear(H5F_t *f, H5FS_sinfo_t *sinfo, hbool_t destroy);
-static herr_t H5FS_cache_sinfo_size(const H5F_t *f, const H5FS_sinfo_t *sinfo, size_t *size_ptr);
+static herr_t H5FS__cache_hdr_get_load_size(const void *udata, size_t *image_len);
+static void *H5FS__cache_hdr_deserialize(const void *image, size_t len,
+    void *udata, hbool_t *dirty);
+static herr_t H5FS__cache_hdr_image_len(const void *thing, size_t *image_len,
+    hbool_t *compressed_ptr, size_t *compressed_image_len_ptr);
+static herr_t H5FS__cache_hdr_pre_serialize(const H5F_t *f, hid_t dxpl_id,
+    void *thing, haddr_t addr, size_t len, size_t compressed_len, 
+    haddr_t *new_addr, size_t *new_len, size_t *new_compressed_len, 
+    unsigned *flags);
+static herr_t H5FS__cache_hdr_serialize(const H5F_t *f, void *image, 
+    size_t len, void *thing);
+static herr_t H5FS__cache_hdr_free_icr(void *thing);
+
+static herr_t H5FS__cache_sinfo_get_load_size(const void *udata, size_t *image_len);
+static void *H5FS__cache_sinfo_deserialize(const void *image, size_t len,
+    void *udata, hbool_t *dirty);
+static herr_t H5FS__cache_sinfo_image_len(const void *thing, size_t *image_len,
+    hbool_t *compressed_ptr, size_t *compressed_image_len_ptr);
+static herr_t H5FS__cache_sinfo_pre_serialize(const H5F_t *f, hid_t dxpl_id,
+    void *thing, haddr_t addr, size_t len, size_t compressed_len, 
+    haddr_t *new_addr, size_t *new_len, size_t *new_compressed_len, 
+    unsigned *flags);
+static herr_t H5FS__cache_sinfo_serialize(const H5F_t *f, void *image,
+    size_t len, void *thing);
+static herr_t H5FS__cache_sinfo_free_icr(void *thing);
 
 
 /*********************/
@@ -97,24 +109,36 @@ static herr_t H5FS_cache_sinfo_size(const H5F_t *f, const H5FS_sinfo_t *sinfo, s
 
 /* H5FS header inherits cache-like properties from H5AC */
 const H5AC_class_t H5AC_FSPACE_HDR[1] = {{
-    H5AC_FSPACE_HDR_ID,
-    (H5AC_load_func_t)H5FS_cache_hdr_load,
-    (H5AC_flush_func_t)H5FS_cache_hdr_flush,
-    (H5AC_dest_func_t)H5FS_cache_hdr_dest,
-    (H5AC_clear_func_t)H5FS_cache_hdr_clear,
-    (H5AC_notify_func_t)NULL,
-    (H5AC_size_func_t)H5FS_cache_hdr_size,
+    H5AC_FSPACE_HDR_ID,                 /* Metadata client ID */
+    "Free Space Header",                /* Metadata client name (for debugging) */
+    H5FD_MEM_FSPACE_HDR,                /* File space memory type for client */
+    H5AC__CLASS_NO_FLAGS_SET,           /* Client class behavior flags */
+    H5FS__cache_hdr_get_load_size,      /* 'get_load_size' callback */
+    H5FS__cache_hdr_deserialize,        /* 'deserialize' callback */
+    H5FS__cache_hdr_image_len,          /* 'image_len' callback */
+    H5FS__cache_hdr_pre_serialize,      /* 'pre_serialize' callback */
+    H5FS__cache_hdr_serialize,          /* 'serialize' callback */
+    NULL,                               /* 'notify' callback */
+    H5FS__cache_hdr_free_icr,           /* 'free_icr' callback */
+    NULL,			        /* 'clear' callback */
+    NULL,                               /* 'fsf_size' callback */
 }};
 
-/* H5FS serialized sections inherit cache-like properties from H5AC */
+/* H5FS section info inherits cache-like properties from H5AC */
 const H5AC_class_t H5AC_FSPACE_SINFO[1] = {{
-    H5AC_FSPACE_SINFO_ID,
-    (H5AC_load_func_t)H5FS_cache_sinfo_load,
-    (H5AC_flush_func_t)H5FS_cache_sinfo_flush,
-    (H5AC_dest_func_t)H5FS_cache_sinfo_dest,
-    (H5AC_clear_func_t)H5FS_cache_sinfo_clear,
-    (H5AC_notify_func_t)NULL,
-    (H5AC_size_func_t)H5FS_cache_sinfo_size,
+    H5AC_FSPACE_SINFO_ID,               /* Metadata client ID */
+    "Free Space Section Info",          /* Metadata client name (for debugging) */
+    H5FD_MEM_FSPACE_SINFO,              /* File space memory type for client */
+    H5AC__CLASS_NO_FLAGS_SET,           /* Client class behavior flags */
+    H5FS__cache_sinfo_get_load_size,    /* 'get_load_size' callback */
+    H5FS__cache_sinfo_deserialize,      /* 'deserialize' callback */
+    H5FS__cache_sinfo_image_len,        /* 'image_len' callback */
+    H5FS__cache_sinfo_pre_serialize,    /* 'pre_serialize' callback */
+    H5FS__cache_sinfo_serialize,        /* 'serialize' callback */
+    NULL,                               /* 'notify' callback */
+    H5FS__cache_sinfo_free_icr,         /* 'free_icr' callback */
+    NULL,			        /* 'clear' callback */
+    NULL,                               /* 'fsf_size' callback */
 }};
 
 
@@ -127,44 +151,73 @@ const H5AC_class_t H5AC_FSPACE_SINFO[1] = {{
 /* Local Variables */
 /*******************/
 
-/* Declare a free list to manage free space section data to/from disk */
-H5FL_BLK_DEFINE_STATIC(sect_block);
-
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5FS_cache_hdr_load
+ * Function:    H5FS__cache_hdr_get_load_size
  *
- * Purpose:	Loads a free space manager header from the disk.
+ * Purpose:     Compute the size of the data structure on disk.
  *
- * Return:      Success:        Pointer to a new free space header
- *              Failure:        NULL
+ * Return:      Non-negative on success/Negative on failure
  *
  * Programmer:  Quincey Koziol
- *              koziol@ncsa.uiuc.edu
- *              May  2 2006
+ *              koziol@hdfgroup.org
+ *              August 14, 2013
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5FS__cache_hdr_get_load_size(const void *_udata, size_t *image_len)
+{
+    const H5FS_hdr_cache_ud_t *udata = (const H5FS_hdr_cache_ud_t *)_udata; /* User-data for metadata cache callback */
+
+    FUNC_ENTER_STATIC_NOERR
+
+    /* Check arguments */
+    HDassert(image_len);
+
+    /* Set the image length size */
+    *image_len = (size_t)H5FS_HEADER_SIZE(udata->f);
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5FS__cache_hdr_get_load_size() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5FS__cache_hdr_deserialize
+ *
+ * Purpose:	Given a buffer containing the on disk image of the free space
+ *      	manager section info, allocate an instance of H5FS_t, load
+ *      	it with the data contained in the image, and return a pointer
+ *              to the new instance.
+ *
+ * Return:	Success:	Pointer to new object
+ *		Failure:	NULL
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@hdfgroup.org
+ *		August 18 2013
  *
  *-------------------------------------------------------------------------
  */
-static H5FS_t *
-H5FS_cache_hdr_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
+static void *
+H5FS__cache_hdr_deserialize(const void *_image, size_t len, void *_udata, 
+    hbool_t H5_ATTR_UNUSED *dirty)
 {
     H5FS_t		*fspace = NULL; /* Free space header info */
-    H5FS_hdr_cache_ud_t *udata = (H5FS_hdr_cache_ud_t *)_udata; /* user data for callback */
-    H5WB_t              *wb = NULL;     /* Wrapped buffer for header data */
-    uint8_t             hdr_buf[H5FS_HDR_BUF_SIZE]; /* Buffer for header */
-    uint8_t		*hdr;           /* Pointer to header buffer */
-    const uint8_t	*p;             /* Pointer into raw data buffer */
+    H5FS_hdr_cache_ud_t *udata = (H5FS_hdr_cache_ud_t *)_udata;  /* User data for callback */
+    const uint8_t	*image = (const uint8_t *)_image;       /* Pointer into raw data buffer */
     uint32_t            stored_chksum;  /* Stored metadata checksum value */
     uint32_t            computed_chksum; /* Computed metadata checksum value */
     unsigned            nclasses;       /* Number of section classes */
     H5FS_t		*ret_value;     /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
     /* Check arguments */
-    HDassert(f);
+    HDassert(image);
     HDassert(udata);
+    HDassert(udata->f);
 
     /* Allocate a new free space manager */
     if(NULL == (fspace = H5FS__new(udata->f, udata->nclasses, udata->classes, udata->cls_init_udata)))
@@ -173,80 +226,69 @@ H5FS_cache_hdr_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
     /* Set free space manager's internal information */
     fspace->addr = udata->addr;
 
-    /* Wrap the local buffer for serialized header info */
-    if(NULL == (wb = H5WB_wrap(hdr_buf, sizeof(hdr_buf))))
-        HGOTO_ERROR(H5E_FSPACE, H5E_CANTINIT, NULL, "can't wrap buffer")
-
-    /* Get a pointer to a buffer that's large enough for header */
-    if(NULL == (hdr = (uint8_t *)H5WB_actual(wb, fspace->hdr_size)))
-        HGOTO_ERROR(H5E_FSPACE, H5E_NOSPACE, NULL, "can't get actual buffer")
-
-    /* Read header from disk */
-    if(H5F_block_read(f, H5FD_MEM_FSPACE_HDR, addr, fspace->hdr_size, dxpl_id, hdr) < 0)
-	HGOTO_ERROR(H5E_FSPACE, H5E_READERROR, NULL, "can't read free space header")
-
-    p = hdr;
-
     /* Magic number */
-    if(HDmemcmp(p, H5FS_HDR_MAGIC, (size_t)H5_SIZEOF_MAGIC))
+    if(HDmemcmp(image, H5FS_HDR_MAGIC, (size_t)H5_SIZEOF_MAGIC))
 	HGOTO_ERROR(H5E_FSPACE, H5E_CANTLOAD, NULL, "wrong free space header signature")
-    p += H5_SIZEOF_MAGIC;
+    image += H5_SIZEOF_MAGIC;
 
     /* Version */
-    if(*p++ != H5FS_HDR_VERSION)
+    if(*image++ != H5FS_HDR_VERSION)
 	HGOTO_ERROR(H5E_FSPACE, H5E_CANTLOAD, NULL, "wrong free space header version")
 
     /* Client ID */
-    fspace->client = (H5FS_client_t)*p++;
+    fspace->client = (H5FS_client_t)*image++;
     if(fspace->client >= H5FS_NUM_CLIENT_ID)
 	HGOTO_ERROR(H5E_FSPACE, H5E_CANTLOAD, NULL, "unknown client ID in free space header")
 
     /* Total space tracked */
-    H5F_DECODE_LENGTH(udata->f, p, fspace->tot_space);
+    H5F_DECODE_LENGTH(udata->f, image, fspace->tot_space);
 
     /* Total # of free space sections tracked */
-    H5F_DECODE_LENGTH(udata->f, p, fspace->tot_sect_count);
+    H5F_DECODE_LENGTH(udata->f, image, fspace->tot_sect_count);
 
     /* # of serializable free space sections tracked */
-    H5F_DECODE_LENGTH(udata->f, p, fspace->serial_sect_count);
+    H5F_DECODE_LENGTH(udata->f, image, fspace->serial_sect_count);
 
     /* # of ghost free space sections tracked */
-    H5F_DECODE_LENGTH(udata->f, p, fspace->ghost_sect_count);
+    H5F_DECODE_LENGTH(udata->f, image, fspace->ghost_sect_count);
 
     /* # of section classes */
     /* (only check if we actually have some classes) */
-    UINT16DECODE(p, nclasses);
+    UINT16DECODE(image, nclasses);
     if(fspace->nclasses > 0 && fspace->nclasses != nclasses)
 	HGOTO_ERROR(H5E_FSPACE, H5E_CANTLOAD, NULL, "section class count mismatch")
 
     /* Shrink percent */
-    UINT16DECODE(p, fspace->shrink_percent);
+    UINT16DECODE(image, fspace->shrink_percent);
 
     /* Expand percent */
-    UINT16DECODE(p, fspace->expand_percent);
+    UINT16DECODE(image, fspace->expand_percent);
 
-    /* Size of address space free space sections are within (log2 of actual value) */
-    UINT16DECODE(p, fspace->max_sect_addr);
+    /* Size of address space free space sections are within 
+     * (log2 of actual value) 
+     */
+    UINT16DECODE(image, fspace->max_sect_addr);
 
     /* Max. size of section to track */
-    H5F_DECODE_LENGTH(udata->f, p, fspace->max_sect_size);
+    H5F_DECODE_LENGTH(udata->f, image, fspace->max_sect_size);
 
     /* Address of serialized free space sections */
-    H5F_addr_decode(udata->f, &p, &fspace->sect_addr);
+    H5F_addr_decode(udata->f, &image, &fspace->sect_addr);
 
     /* Size of serialized free space sections */
-    H5F_DECODE_LENGTH(udata->f, p, fspace->sect_size);
+    H5F_DECODE_LENGTH(udata->f, image, fspace->sect_size);
 
     /* Allocated size of serialized free space sections */
-    H5F_DECODE_LENGTH(udata->f, p, fspace->alloc_sect_size);
+    H5F_DECODE_LENGTH(udata->f, image, fspace->alloc_sect_size);
 
     /* Compute checksum on indirect block */
-    computed_chksum = H5_checksum_metadata(hdr, (size_t)(p - (const uint8_t *)hdr), 0);
+    computed_chksum = H5_checksum_metadata(_image, (size_t)(image - (const uint8_t *)_image), 0);
 
     /* Metadata checksum */
-    UINT32DECODE(p, stored_chksum);
+    UINT32DECODE(image, stored_chksum);
 
-    HDassert((size_t)(p - (const uint8_t *)hdr) == fspace->hdr_size);
+    /* Sanity check */
+    HDassert((size_t)(image - (const uint8_t *)_image) <= len);
 
     /* Verify checksum */
     if(stored_chksum != computed_chksum)
@@ -257,177 +299,432 @@ H5FS_cache_hdr_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
 
 done:
     /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-        HDONE_ERROR(H5E_FSPACE, H5E_CLOSEERROR, NULL, "can't close wrapped buffer")
     if(!ret_value && fspace)
         if(H5FS__hdr_dest(fspace) < 0)
             HDONE_ERROR(H5E_FSPACE, H5E_CANTFREE, NULL, "unable to destroy free space header")
 
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5FS_cache_hdr_load() */ /*lint !e818 Can't make udata a pointer to const */
+} /* end H5FS__cache_hdr_deserialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5FS_cache_hdr_flush
+ * Function:    H5FS__cache_hdr_image_len
  *
- * Purpose:	Flushes a dirty free space header to disk.
+ * Purpose:     Compute the size of the data structure on disk and return
+ *              it in *image_len.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
  * Programmer:  Quincey Koziol
- *              koziol@ncsa.uiuc.edu
- *              May  2 2006
+ *              koziol@hdfgroup.org
+ *              August 14, 2013
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5FS_cache_hdr_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5FS_t *fspace, unsigned H5_ATTR_UNUSED * flags_ptr)
+H5FS__cache_hdr_image_len(const void *_thing, size_t *image_len,
+    hbool_t H5_ATTR_UNUSED *compressed_ptr, size_t H5_ATTR_UNUSED *compressed_image_len_ptr)
 {
-    H5WB_t      *wb = NULL;             /* Wrapped buffer for header data */
-    uint8_t     hdr_buf[H5FS_HDR_BUF_SIZE]; /* Buffer for header */
-    herr_t ret_value = SUCCEED;         /* Return value */
+    const H5FS_t *fspace = (const H5FS_t *)_thing;       /* Pointer to the object */
+
+    FUNC_ENTER_STATIC_NOERR
+
+    /* Check arguments */
+    HDassert(fspace);
+    HDassert(fspace->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(fspace->cache_info.type == H5AC_FSPACE_HDR);
+    HDassert(image_len);
+
+    /* Set the image length size */
+    *image_len = fspace->hdr_size;
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5FS__cache_hdr_image_len() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5FS__cache_hdf_pre_serialize
+ *
+ * Purpose:	The free space manager header contains the address, size, and 
+ *		allocation size of the free space manager section info.  However,
+ *		since it is possible for the section info to either not be allocated
+ *		at all, or be allocated in temporary (AKA imaginary) files space,
+ *		it is possible for the above mentioned fields to contain giberish
+ *		when the free space manager header is serialized.
+ *
+ *		This function exists to prevent this problem.  It does so by 
+ *		forcing allocation of real file space for the section information.
+ *
+ *		Note that in the Version 2 cache, this problem was dealt with by
+ *		simply flushing the section info before flushing the header.  This
+ *		was possible, since the clients handled file I/O directly.  As 
+ *		this responsibility has moved to the cache in Version 3, this 
+ *		solution is no longer directly applicable.
+ *
+ * Return:	Success:	SUCCEED
+ *		Failure:	FAIL
+ *
+ * Programmer:	John Mainzer
+ *		6/21/14
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t 
+H5FS__cache_hdr_pre_serialize(const H5F_t *f, hid_t dxpl_id, void *_thing,
+    haddr_t addr, size_t H5_ATTR_UNUSED len, size_t H5_ATTR_UNUSED compressed_len, 
+    haddr_t *new_addr, size_t *new_len, size_t H5_ATTR_UNUSED *new_compressed_len, 
+    unsigned *flags)
+{
+    H5FS_t 	*fspace = (H5FS_t *)_thing;     /* Pointer to the object */
+    herr_t     	 ret_value = SUCCEED;           /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC_TAG(dxpl_id, H5AC__FREESPACE_TAG, FAIL)
 
-    /* check arguments */
+    /* Sanity check */
     HDassert(f);
-    HDassert(H5F_addr_defined(addr));
     HDassert(fspace);
-    HDassert(H5F_addr_defined(fspace->addr));
+    HDassert(fspace->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(fspace->cache_info.type == H5AC_FSPACE_HDR);
+    HDassert(H5F_addr_defined(addr));
+    HDassert(new_addr);
+    HDassert(new_len);
+    HDassert(flags);
 
-    /* Check if the header "owns" the section info */
     if(fspace->sinfo) {
-        /* Sanity check - should not be trying to destroy header if it still
-         *      "owns" section info
+        /* This implies that the header "owns" the section info.  
+         *
+         * Unfortunately, the comments in the code are not clear as to 
+	 * what this means, but from reviewing the code (most particularly
+         * H5FS_close(), H5FS_sinfo_lock, and H5FS_sinfo_unlock()), I 
+         * gather that it means that the header is maintaining a pointer to 
+         * an instance of H5FS_sinfo_t in which free space data is 
+         * maintained, and either:
+         *
+         * 1) The instance of H5FS_sinfo_t is not in the metadata cache.
+         *
+         *    This will be TRUE iff H5F_addr_defined(fspace->sect_addr) 
+         *    is FALSE, and fspace->sinfo is not NULL.  This is sometimes
+         *    referred to as "floating" section info in the comments.
+         *
+         *    If the section info structure contains free space data 
+         *    that must be placed on disk eventually, then 
+         *
+         *        fspace->serial_sect_count > 0
+         *
+         *    and
+         *
+         *        H5F_addr_defined(fspace->addr)
+         *
+         *    will both be TRUE.  If this contition does not hold, then
+         *    either the free space info is not persistant 
+         *    (!H5F_addr_defined(fspace->addr)???) or the section info 
+         *    contains no free space data that must be written to file 
+         *    ( fspace->serial_sect_count == 0 ).
+         *
+         * 2) The instance of H5FS_sinfo_t is in the metadata cache with
+         *    address in temporary file space (AKA imaginary file space).
+         *    The entry may or may not be protected, and if protected, it 
+         *    may be protected either RW or RO (as indicated by 
+         *    fspace->sinfo_protected and  fspace->sinfo_accmod).
+         *
+         * 3) The instance of H5FS_sinfo_t is in the metadata cache with
+         *    address in real file space.  As in case 2) above, the entry
+         *    may or may not be protected, and if protected, it 
+         *    may be protected either RW or RO (as indicated by 
+         *    fspace->sinfo_protected and  fspace->sinfo_accmod).
+         *
+         * Observe that fspace->serial_sect_count > 0 must be TRUE in 
+         * cases 2) and 3), as the section info should not be stored on 
+         * disk if it doesn't exist.  Similarly, since the section info
+         * will not be stored to disk unless the header is, 
+         * H5F_addr_defined(fspace->addr) must hold as well.
+	 *
+         * As the objective is to touch up the free space manager header
+         * so that it contains sensical data on the size and location of 
+         * the section information, we have to handle each of the above
+         * cases differently.
+         *
+         * Case 1) If either fspace->serial_sect_count == 0 or 
+         *         ! H5F_addr_defined(fspace->addr) do nothing as either 
+         *         the free space manager data is not persistant, or the 
+         *         section info is empty.
+         *
+         *         Otherwise, allocate space for the section info in real
+         *         file space, insert the section info at this location, and 
+         *         set fspace->sect_addr, fspace->sect_size, and 
+         *	   fspace->alloc_sect_size to reflect the new location
+         *	   of the section info.  Note that it is not necessary to
+         *         force a write of the section info.
+         *
+         * Case 2) Allocate space for the section info in real file space,
+         *         and tell the metadata cache to relocate the entry.  
+         *         Update fspace->sect_addr, fspace->sect_size, and 
+         *         fspace->alloc_sect_size to reflect the new location.
+         *
+         * Case 3) Nothing to be done in this case, although it is useful
+         *         to perform sanity checks.
+         *
+         * Note that while we may alter the contents of the free space 
+         * header in cases 1) and 2), there is no need to mark the header 
+         * as dirty, as the metadata cache would not be attempting to 
+         * serialize the header if it though it was clean.
          */
-        HDassert(!destroy);
-
-        /* Check if the section info is dirty */
-        if(fspace->sinfo->dirty) {
-            if(fspace->serial_sect_count > 0) {
-                /* Check if we need to allocate space for  section info */
-                if(H5F_IS_TMP_ADDR(f, fspace->sect_addr) || !H5F_addr_defined(fspace->sect_addr)) {
-                    /* Sanity check */
-                    HDassert(fspace->sect_size > 0);
-
-                    /* Allocate space for the section info in file */
-                    if(HADDR_UNDEF == (fspace->sect_addr = H5MF_alloc(f, H5FD_MEM_FSPACE_SINFO, dxpl_id, fspace->sect_size)))
-                        HGOTO_ERROR(H5E_FSPACE, H5E_NOSPACE, FAIL, "file allocation failed for free space sections")
-                    fspace->alloc_sect_size = (size_t)fspace->sect_size;
-
-                    /* Mark header dirty */
-                    /* (don't use cache API, since we're in a callback) */
-                    fspace->cache_info.is_dirty = TRUE;
-                } /* end if */
-
-                /* Write section info to file */
-                if(H5FS_cache_sinfo_flush(f, dxpl_id, FALSE, fspace->sect_addr, fspace->sinfo, NULL) < 0)
-                    HGOTO_ERROR(H5E_FSPACE, H5E_CANTFLUSH, FAIL, "unable to save free space section info to disk")
+        if(fspace->serial_sect_count > 0 && H5F_addr_defined(fspace->addr)) {
+	    /* Sanity check */
+            HDassert(fspace->sect_size > 0);
+
+            if(!H5F_addr_defined(fspace->sect_addr)) { /* case 1 */
+		/* allocate file space for the section info, and insert it
+                 * into the metadata cache.
+                 */
+                if(HADDR_UNDEF == (fspace->sect_addr = H5MF_alloc((H5F_t *)f, H5FD_MEM_FSPACE_SINFO, dxpl_id, fspace->sect_size)))
+                    HGOTO_ERROR(H5E_FSPACE, H5E_NOSPACE, FAIL, "file allocation failed for free space sections")
+
+                fspace->alloc_sect_size = (size_t)fspace->sect_size;
+		if(H5AC_insert_entry((H5F_t *)f, dxpl_id, H5AC_FSPACE_SINFO, fspace->sect_addr, fspace->sinfo, H5AC__NO_FLAGS_SET) < 0)
+                    HGOTO_ERROR(H5E_FSPACE, H5E_CANTINIT, FAIL, "can't add free space sections to cache")
+
+                HDassert(fspace->sinfo->cache_info.size == fspace->alloc_sect_size);
+
+                /* the metadata cache is now managing the section info, 
+                 * so set fspace->sinfo to NULL.
+                 */
+                fspace->sinfo = NULL;
             } /* end if */
-
-            /* Mark section info clean */
-            fspace->sinfo->dirty = FALSE;
-        } /* end if */
+            else if(H5F_IS_TMP_ADDR(f, fspace->sect_addr)) { /* case 2 */
+                haddr_t new_sect_addr;
+
+		/* move the section info from temporary (AKA imaginary) file
+                 * space to real file space.
+                 */
+
+                /* if my reading of the code is correct, this should always
+                 * be the case.  If not, we will have to add code to resize
+                 * file space allocation for section info as well as moving it.
+                 */
+                HDassert(fspace->sect_size > 0);
+                HDassert(fspace->alloc_sect_size == (size_t)fspace->sect_size);
+
+                /* Allocate space for the section info in file */
+                if(HADDR_UNDEF == (new_sect_addr = H5MF_alloc((H5F_t *)f, H5FD_MEM_FSPACE_SINFO, dxpl_id, fspace->sect_size)))
+                    HGOTO_ERROR(H5E_FSPACE, H5E_NOSPACE, FAIL, "file allocation failed for free space sections")
+
+                fspace->alloc_sect_size = (size_t)fspace->sect_size;
+                HDassert(fspace->sinfo->cache_info.size == fspace->alloc_sect_size);
+
+                /* Let the metadata cache know the section info moved */
+                if(H5AC_move_entry((H5F_t *)f, H5AC_FSPACE_SINFO, fspace->sect_addr, new_sect_addr) < 0)
+                    HGOTO_ERROR(H5E_HEAP, H5E_CANTMOVE, FAIL, "unable to move section info")
+
+                fspace->sect_addr = new_sect_addr;
+            } /* end else-if */
+            else { /* case 3 -- nothing to do but sanity checking */
+                /* if my reading of the code is correct, this should always
+                 * be the case.  If not, we will have to add code to resize
+                 * file space allocation for section info.
+                 */
+                HDassert(fspace->sect_size > 0);
+                HDassert(fspace->alloc_sect_size == (size_t)fspace->sect_size);
+            } /* end else */
+        } /* end else */
+        else {
+            /* for one reason or another (see comment above) there should
+             * not be any file space allocated for the section info.
+             */
+	    HDassert(!H5F_addr_defined(fspace->sect_addr));
+        } /* end else */
     } /* end if */
-    else if(fspace->serial_sect_count > 0)
-	/* Sanity check that section info has address */
-	HDassert(H5F_addr_defined(fspace->sect_addr));
+    else if(H5F_addr_defined(fspace->sect_addr)) {
+        /* Here the metadata cache is managing the section info.  
+         *
+         * Do some sanity checks, and then test to see if the section 
+         * info is in real file space.  If it isn't relocate it into 
+         * real file space lest the header be written to file with 
+         * a nonsense section info address.
+         */
+        HDassert(fspace->serial_sect_count > 0);
+        HDassert(fspace->sect_size > 0);
+        HDassert(fspace->alloc_sect_size == (size_t)fspace->sect_size);
+
+        if(H5F_IS_TMP_ADDR(f, fspace->sect_addr)) {
+            unsigned sect_status = 0;
+            haddr_t new_sect_addr;
+
+	    /* we have work to do -- must relocate section info into 
+             * real file space.
+             *
+             * Since the section info address is in temporary space (AKA
+             * imaginary space), it follows that the entry must be in 
+             * cache.  Further, since fspace->sinfo is NULL, it must be 
+             * unprotected and un-pinned.  Start by verifying this.
+             */
+            if(H5AC_get_entry_status(f, fspace->sect_addr, &sect_status) < 0)
+                HGOTO_ERROR(H5E_FSPACE, H5E_CANTGET, FAIL, "can't get section info status")
+
+            HDassert(sect_status & H5AC_ES__IN_CACHE);
+            HDassert((sect_status & H5AC_ES__IS_PROTECTED) == 0);
+            HDassert((sect_status & H5AC_ES__IS_PINNED) == 0);
 
-    if(fspace->cache_info.is_dirty) {
-        uint8_t	*hdr;                   /* Pointer to header buffer */
-        uint8_t *p;                     /* Pointer into raw data buffer */
-        uint32_t metadata_chksum;       /* Computed metadata checksum value */
+            /* Allocate space for the section info in file */
+            if(HADDR_UNDEF == (new_sect_addr = H5MF_alloc((H5F_t *)f, H5FD_MEM_FSPACE_SINFO, dxpl_id, fspace->sect_size)))
+                HGOTO_ERROR(H5E_FSPACE, H5E_NOSPACE, FAIL, "file allocation failed for free space sections")
 
-        /* Wrap the local buffer for serialized header info */
-        if(NULL == (wb = H5WB_wrap(hdr_buf, sizeof(hdr_buf))))
-            HGOTO_ERROR(H5E_FSPACE, H5E_CANTINIT, FAIL, "can't wrap buffer")
+            fspace->alloc_sect_size = (size_t)fspace->sect_size;
 
-        /* Get a pointer to a buffer that's large enough for header */
-        if(NULL == (hdr = (uint8_t *)H5WB_actual(wb, fspace->hdr_size)))
-            HGOTO_ERROR(H5E_FSPACE, H5E_NOSPACE, FAIL, "can't get actual buffer")
+            /* Sanity check */
+            HDassert(!H5F_addr_eq(fspace->sect_addr, new_sect_addr));
 
-        /* Get temporary pointer to header */
-        p = hdr;
+            /* Let the metadata cache know the section info moved */
+            if(H5AC_move_entry((H5F_t *)f, H5AC_FSPACE_SINFO, fspace->sect_addr, new_sect_addr) < 0)
+                HGOTO_ERROR(H5E_FSPACE, H5E_CANTMOVE, FAIL, "unable to move section info")
 
-        /* Magic number */
-        HDmemcpy(p, H5FS_HDR_MAGIC, (size_t)H5_SIZEOF_MAGIC);
-        p += H5_SIZEOF_MAGIC;
+            /* Update the internal address for the section info */
+            fspace->sect_addr = new_sect_addr;
 
-        /* Version # */
-        *p++ = H5FS_HDR_VERSION;
+            /* No need to mark the header dirty, as we are about to 
+             * serialize it.
+             */
+        } /* end if */
+    } /* end else-if */
+    else {      /* there is no section info at present */
+        /* do some sanity checks */
+        HDassert(fspace->serial_sect_count == 0);
+        HDassert(fspace->tot_sect_count == fspace->ghost_sect_count);
+    } /* end else */
 
-        /* Client ID */
-        *p++ = fspace->client;
+    /* what ever happened above, set *flags to 0 */
+    *flags = 0;
 
-        /* Total space tracked */
-        H5F_ENCODE_LENGTH(f, p, fspace->tot_space);
+done:
+    FUNC_LEAVE_NOAPI_TAG(ret_value, FAIL)
+} /* end H5FS__cache_hdr_pre_serialize() */
 
-        /* Total # of free space sections tracked */
-        H5F_ENCODE_LENGTH(f, p, fspace->tot_sect_count);
+
+/*-------------------------------------------------------------------------
+ * Function:    H5FS__cache_hdr_serialize
+ *
+ * Purpose: 	Given an instance of H5FS_t and a suitably sized buffer,
+ *      	serialize the contents of the instance of H5FS_t and write
+ *      	its contents to the buffer.  This buffer will be used to 
+ *      	write the image of the instance to file.
+ *
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
+ *
+ * Programmer:  John Mainzer
+ *              6/21/14
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5FS__cache_hdr_serialize(const H5F_t *f, void *_image, size_t len,
+    void *_thing)
+{
+    H5FS_t     *fspace = (H5FS_t *)_thing;      /* Pointer to the object */
+    uint8_t    *image = (uint8_t *)_image;      /* Pointer into raw data buffer */
+    uint32_t    metadata_chksum;       /* Computed metadata checksum value */
+    herr_t      ret_value = SUCCEED;   /* Return value */
 
-        /* # of serializable free space sections tracked */
-        H5F_ENCODE_LENGTH(f, p, fspace->serial_sect_count);
+    FUNC_ENTER_STATIC_NOERR
 
-        /* # of ghost free space sections tracked */
-        H5F_ENCODE_LENGTH(f, p, fspace->ghost_sect_count);
+    /* Check arguments */
+    HDassert(f);
+    HDassert(image);
+    HDassert(fspace);
+    HDassert(fspace->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(fspace->cache_info.type == H5AC_FSPACE_HDR);
+    HDassert(fspace->hdr_size == len);
+
+    /* The section information does not always exits, and if it does, 
+     * it is not always in the cache.  To make matters more interesting, 
+     * even if it is in the cache, it may not be in real file space.
+     *
+     * The pre-serialize function should have moved the section info 
+     * into real file space if necessary before this function was called.
+     * The following asserts are a cursory check on this.
+     */
+    HDassert((! H5F_addr_defined(fspace->sect_addr)) || (! H5F_IS_TMP_ADDR(f, fspace->sect_addr)));
+    HDassert((! H5F_addr_defined(fspace->sect_addr)) || 
+             ((fspace->serial_sect_count > 0) && 
+              (fspace->sect_size > 0) && 
+              (fspace->alloc_sect_size == (size_t)fspace->sect_size)));
 
-        /* # of section classes */
-        UINT16ENCODE(p, fspace->nclasses);
+    /* Magic number */
+    HDmemcpy(image, H5FS_HDR_MAGIC, (size_t)H5_SIZEOF_MAGIC);
+    image += H5_SIZEOF_MAGIC;
 
-        /* Shrink percent */
-        UINT16ENCODE(p, fspace->shrink_percent);
+    /* Version # */
+    *image++ = H5FS_HDR_VERSION;
 
-        /* Expand percent */
-        UINT16ENCODE(p, fspace->expand_percent);
+    /* Client ID */
+    *image++ = fspace->client;
 
-        /* Size of address space free space sections are within (log2 of actual value) */
-        UINT16ENCODE(p, fspace->max_sect_addr);
+    /* Total space tracked */
+    H5F_ENCODE_LENGTH(f, image, fspace->tot_space);
 
-        /* Max. size of section to track */
-        H5F_ENCODE_LENGTH(f, p, fspace->max_sect_size);
+    /* Total # of free space sections tracked */
+    H5F_ENCODE_LENGTH(f, image, fspace->tot_sect_count);
 
-        /* Address of serialized free space sections */
-        H5F_addr_encode(f, &p, fspace->sect_addr);
+    /* # of serializable free space sections tracked */
+    H5F_ENCODE_LENGTH(f, image, fspace->serial_sect_count);
 
-        /* Size of serialized free space sections */
-        H5F_ENCODE_LENGTH(f, p, fspace->sect_size);
+    /* # of ghost free space sections tracked */
+    H5F_ENCODE_LENGTH(f, image, fspace->ghost_sect_count);
 
-        /* Allocated size of serialized free space sections */
-        H5F_ENCODE_LENGTH(f, p, fspace->alloc_sect_size);
+    /* # of section classes */
+    UINT16ENCODE(image, fspace->nclasses);
 
-        /* Compute checksum */
-        metadata_chksum = H5_checksum_metadata(hdr, (size_t)(p - (uint8_t *)hdr), 0);
+    /* Shrink percent */
+    UINT16ENCODE(image, fspace->shrink_percent);
 
-        /* Metadata checksum */
-        UINT32ENCODE(p, metadata_chksum);
+    /* Expand percent */
+    UINT16ENCODE(image, fspace->expand_percent);
 
-	/* Write the free space header. */
-        HDassert((size_t)(p - hdr) == fspace->hdr_size);
-	if(H5F_block_write(f, H5FD_MEM_FSPACE_HDR, addr, fspace->hdr_size, dxpl_id, hdr) < 0)
-	    HGOTO_ERROR(H5E_FSPACE, H5E_CANTFLUSH, FAIL, "unable to save free space header to disk")
+    /* Size of address space free space sections are within (log2 of 
+     * actual value) 
+     */
+    UINT16ENCODE(image, fspace->max_sect_addr);
 
-	fspace->cache_info.is_dirty = FALSE;
-    } /* end if */
+    /* Max. size of section to track */
+    H5F_ENCODE_LENGTH(f, image, fspace->max_sect_size);
 
-    if(destroy)
-        if(H5FS_cache_hdr_dest(f, fspace) < 0)
-	    HGOTO_ERROR(H5E_FSPACE, H5E_CANTFREE, FAIL, "unable to destroy free space header")
+    /* Address of serialized free space sections */
+    H5F_addr_encode(f, &image, fspace->sect_addr);
 
-done:
-    /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-        HDONE_ERROR(H5E_FSPACE, H5E_CLOSEERROR, FAIL, "can't close wrapped buffer")
+    /* Size of serialized free space sections */
+    H5F_ENCODE_LENGTH(f, image, fspace->sect_size);
+
+    /* Allocated size of serialized free space sections */
+    H5F_ENCODE_LENGTH(f, image, fspace->alloc_sect_size);
+
+    /* Compute checksum */
+    metadata_chksum = H5_checksum_metadata((uint8_t *)_image, (size_t)(image - (uint8_t *)_image), 0);
+
+    /* Metadata checksum */
+    UINT32ENCODE(image, metadata_chksum);
+
+    /* sanity checks */
+    HDassert((size_t)(image - (uint8_t *)_image) == fspace->hdr_size);
 
     FUNC_LEAVE_NOAPI(ret_value)
-} /* H5FS_cache_hdr_flush() */
+} /* H5FS__cache_hdr_serialize() */
+
+/***************************************/
+/* no H5FS__cache_hdr_notify() function */
+/***************************************/
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5FS_cache_hdr_dest
+ * Function:	H5FS__cache_hdr_free_icr
  *
  * Purpose:	Destroys a free space header in memory.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Note:	The metadata cache sets the object's cache_info.magic to
+ *		H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC before calling a free_icr
+ *		callback (checked in assert).
+ *
+ * Return:	Success:        SUCCEED
+ *              Failure:        FAIL
  *
  * Programmer:	Quincey Koziol
  *		koziol@ncsa.uiuc.edu
@@ -436,175 +733,133 @@ done:
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5FS_cache_hdr_dest(H5F_t *f, H5FS_t *fspace)
+H5FS__cache_hdr_free_icr(void *_thing)
 {
-    herr_t ret_value = SUCCEED; /* Return value */
+    H5FS_t *fspace = (H5FS_t *)_thing;  /* Pointer to the object */
+    herr_t ret_value = SUCCEED;         /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
-    /* Check arguments */
+    /* Sanity checks */
     HDassert(fspace);
+    HDassert(fspace->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC);
+    HDassert(fspace->cache_info.type == H5AC_FSPACE_HDR);
 
     /* We should not still be holding on to the free space section info */
     HDassert(!fspace->sinfo);
 
-    /* If we're going to free the space on disk, the address must be valid */
-    HDassert(!fspace->cache_info.free_file_space_on_destroy || H5F_addr_defined(fspace->cache_info.addr));
-
-    /* Check for freeing file space for free space header */
-    if(fspace->cache_info.free_file_space_on_destroy) {
-        /* Sanity check */
-        HDassert(H5F_addr_defined(fspace->addr));
-
-        /* Release the space on disk */
-        /* (XXX: Nasty usage of internal DXPL value! -QAK) */
-        if(H5MF_xfree(f, H5FD_MEM_FSPACE_HDR, H5AC_dxpl_id, fspace->cache_info.addr, (hsize_t)fspace->hdr_size) < 0)
-            HGOTO_ERROR(H5E_FSPACE, H5E_CANTFREE, FAIL, "unable to free free space header")
-    } /* end if */
-
     /* Destroy free space header */
     if(H5FS__hdr_dest(fspace) < 0)
         HGOTO_ERROR(H5E_FSPACE, H5E_CANTFREE, FAIL, "unable to destroy free space header")
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5FS_cache_hdr_dest() */
+} /* end H5FS__cache_hdr_free_icr() */
 
-
-/*-------------------------------------------------------------------------
- * Function:	H5FS_cache_hdr_clear
- *
- * Purpose:	Mark a free space header in memory as non-dirty.
- *
- * Return:	Non-negative on success/Negative on failure
- *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		May  2 2006
- *
- *-------------------------------------------------------------------------
- */
-static herr_t
-H5FS_cache_hdr_clear(H5F_t *f, H5FS_t *fspace, hbool_t destroy)
-{
-    herr_t ret_value = SUCCEED;         /* Return value */
-
-    FUNC_ENTER_NOAPI_NOINIT
-
-    /*
-     * Check arguments.
-     */
-    HDassert(fspace);
-
-    /* Reset the dirty flag.  */
-    fspace->cache_info.is_dirty = FALSE;
-
-    if(destroy)
-        if(H5FS_cache_hdr_dest(f, fspace) < 0)
-	    HGOTO_ERROR(H5E_FSPACE, H5E_CANTFREE, FAIL, "unable to destroy free space header")
-
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5FS_cache_hdr_clear() */
+/********************************************************/
+/* metadata cache callback definitions for section info */
+/********************************************************/
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5FS_cache_hdr_size
+ * Function:	H5FS__cache_sinfo_get_load_size()
  *
- * Purpose:	Compute the size in bytes of a free space header
- *		on disk, and return it in *size_ptr.  On failure,
- *		the value of *size_ptr is undefined.
+ * Purpose:	Compute the size of the on disk image of the free space 
+ *		manager section info, and place this value in *image_len.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:	Success:	SUCCEED
+ *		Failure:	FAIL
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		May  2 2006
+ * Programmer:	John Mainzer
+ *		7/7/14
  *
  *-------------------------------------------------------------------------
  */
-static herr_t
-H5FS_cache_hdr_size(const H5F_t H5_ATTR_UNUSED *f, const H5FS_t *fspace, size_t *size_ptr)
+static herr_t 
+H5FS__cache_sinfo_get_load_size(const void  *_udata, size_t *image_len)
 {
-    FUNC_ENTER_NOAPI_NOINIT_NOERR
+    const H5FS_t 		*fspace;        /* free space manager */
+    const H5FS_sinfo_cache_ud_t *udata = (const H5FS_sinfo_cache_ud_t *)_udata; /* User data for callback */
 
-    /* check arguments */
-    HDassert(f);
+    FUNC_ENTER_STATIC_NOERR
+
+    /* Sanity checks */
+    HDassert(udata);
+    fspace = udata->fspace;
     HDassert(fspace);
-    HDassert(size_ptr);
+    HDassert(fspace->sect_size > 0);
+    HDassert(image_len);
 
-    /* Set size value */
-    *size_ptr = fspace->hdr_size;
+    *image_len = (size_t)(fspace->sect_size);
 
     FUNC_LEAVE_NOAPI(SUCCEED)
-} /* H5FS_cache_hdr_size() */
+} /* end H5FS__cache_sinfo_get_load_size() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5FS_cache_sinfo_load
+ * Function:	H5FS__cache_sinfo_deserialize
  *
- * Purpose:	Loads free space sections from the disk.
+ * Purpose:	Given a buffer containing the on disk image of the free space
+ *		manager section info, allocate an instance of H5FS_sinfo_t, load
+ *		it with the data contained in the image, and return a pointer to
+ *		the new instance.
  *
- * Return:      Success:        Pointer to a new free space section info
- *              Failure:        NULL
  *
- * Programmer:  Quincey Koziol
- *              koziol@ncsa.uiuc.edu
- *              July 31 2006
+ * Return:	Success:	Pointer to in core representation
+ *		Failure:	NULL
+ *
+ * Programmer:	John Mainzer
+ *		7/7/14
  *
  *-------------------------------------------------------------------------
  */
-static H5FS_sinfo_t *
-H5FS_cache_sinfo_load(H5F_t *f, hid_t dxpl_id, haddr_t H5_ATTR_UNUSED addr, void *_udata)
+static void *
+H5FS__cache_sinfo_deserialize(const void *_image, size_t len, void *_udata,
+    hbool_t *dirty)
 {
-    H5FS_sinfo_t	*sinfo = NULL;  /* Free space section info */
-    H5FS_sinfo_cache_ud_t *udata = (H5FS_sinfo_cache_ud_t *)_udata; /* user data for callback */
-    haddr_t             fs_addr;        /* Free space header address */
-    size_t              old_sect_size;  /* Old section size */
-    uint8_t		*buf = NULL;    /* Temporary buffer */
-    const uint8_t	*p;             /* Pointer into raw data buffer */
-    uint32_t            stored_chksum;  /* Stored metadata checksum value */
-    uint32_t            computed_chksum; /* Computed metadata checksum value */
-    H5FS_sinfo_t	*ret_value;     /* Return value */
-
-    FUNC_ENTER_NOAPI_NOINIT
-
-    /* Check arguments */
-    HDassert(f);
+    H5FS_sinfo_cache_ud_t  *udata = (H5FS_sinfo_cache_ud_t *)_udata;    /* User data for callback */
+    H5FS_t                 *fspace;         /* free space manager */
+    H5FS_sinfo_t           *sinfo = NULL;   /* Free space section info */
+    haddr_t                 fs_addr;        /* Free space header address */
+    size_t                  old_sect_size;  /* Old section size */
+    const uint8_t          *image = (const uint8_t *)_image;    /* Pointer into raw data buffer */
+    uint32_t                stored_chksum;  /* Stored metadata checksum  */
+    uint32_t                computed_chksum; /* Computed metadata checksum */
+    void *                  ret_value;      /* Return value */
+
+    FUNC_ENTER_STATIC
+
+    /* Sanity checks */
+    HDassert(image);
     HDassert(udata);
+    fspace = udata->fspace;
+    HDassert(fspace);
+    HDassert(fspace->sect_size == len);
+    HDassert(dirty);
 
     /* Allocate a new free space section info */
-    if(NULL == (sinfo = H5FS_sinfo_new(udata->f, udata->fspace)))
-	HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed")
-
-    /* Allocate space for the buffer to serialize the sections into */
-    H5_CHECKED_ASSIGN(old_sect_size, size_t, udata->fspace->sect_size, hsize_t);
-    if(NULL == (buf = H5FL_BLK_MALLOC(sect_block, (size_t)udata->fspace->sect_size)))
+    if(NULL == (sinfo = H5FS_sinfo_new(udata->f, fspace)))
         HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed")
 
-    /* Read buffer from disk */
-    if(H5F_block_read(f, H5FD_MEM_FSPACE_SINFO, udata->fspace->sect_addr, (size_t)udata->fspace->sect_size, dxpl_id, buf) < 0)
-	HGOTO_ERROR(H5E_FSPACE, H5E_READERROR, NULL, "can't read free space sections")
-
-    /* Deserialize free sections from buffer available */
-    p = buf;
+    /* initialize old_sect_size */
+    H5_CHECKED_ASSIGN(old_sect_size, size_t, udata->fspace->sect_size, hsize_t);
 
     /* Magic number */
-    if(HDmemcmp(p, H5FS_SINFO_MAGIC, (size_t)H5_SIZEOF_MAGIC))
-	HGOTO_ERROR(H5E_FSPACE, H5E_CANTLOAD, NULL, "wrong free space sections signature")
-    p += H5_SIZEOF_MAGIC;
+    if(HDmemcmp(image, H5FS_SINFO_MAGIC, (size_t)H5_SIZEOF_MAGIC))
+        HGOTO_ERROR(H5E_FSPACE, H5E_CANTLOAD, NULL, "wrong free space sections signature")
+    image += H5_SIZEOF_MAGIC;
 
     /* Version */
-    if(*p++ != H5FS_SINFO_VERSION)
-	HGOTO_ERROR(H5E_FSPACE, H5E_CANTLOAD, NULL, "wrong free space sections version")
+    if(*image++ != H5FS_SINFO_VERSION)
+        HGOTO_ERROR(H5E_FSPACE, H5E_CANTLOAD, NULL, "wrong free space sections version")
 
     /* Address of free space header for these sections */
-    H5F_addr_decode(udata->f, &p, &fs_addr);
+    H5F_addr_decode(udata->f, &image, &fs_addr);
     if(H5F_addr_ne(fs_addr, udata->fspace->addr))
-	HGOTO_ERROR(H5E_FSPACE, H5E_CANTLOAD, NULL, "incorrect header address for free space sections")
+        HGOTO_ERROR(H5E_FSPACE, H5E_CANTLOAD, NULL, "incorrect header address for free space sections")
 
     /* Check for any serialized sections */
-    if(udata->fspace->serial_sect_count > 0) {
+    if(fspace->serial_sect_count > 0) {
         hsize_t old_tot_sect_count;     /* Total section count from header */
         hsize_t old_serial_sect_count;  /* Total serializable section count from header */
         hsize_t old_ghost_sect_count;   /* Total ghost section count from header */
@@ -615,27 +870,27 @@ H5FS_cache_sinfo_load(H5F_t *f, hid_t dxpl_id, haddr_t H5_ATTR_UNUSED addr, void
         sect_cnt_size = H5VM_limit_enc_size((uint64_t)udata->fspace->serial_sect_count);
 
         /* Reset the section count, the "add" routine will update it */
-        old_tot_sect_count = udata->fspace->tot_sect_count;
-        old_serial_sect_count = udata->fspace->serial_sect_count;
-        old_ghost_sect_count = udata->fspace->ghost_sect_count;
-        old_tot_space = udata->fspace->tot_space;
-        udata->fspace->tot_sect_count = 0;
-        udata->fspace->serial_sect_count = 0;
-        udata->fspace->ghost_sect_count = 0;
-        udata->fspace->tot_space = 0;
-
-        /* Walk through the buffer, deserializing sections */
+        old_tot_sect_count = fspace->tot_sect_count;
+        old_serial_sect_count = fspace->serial_sect_count;
+        old_ghost_sect_count = fspace->ghost_sect_count;
+        old_tot_space = fspace->tot_space;
+        fspace->tot_sect_count = 0;
+        fspace->serial_sect_count = 0;
+        fspace->ghost_sect_count = 0;
+        fspace->tot_space = 0;
+
+        /* Walk through the image, deserializing sections */
         do {
             hsize_t sect_size;      /* Current section size */
             size_t node_count;      /* # of sections of this size */
             size_t u;               /* Local index variable */
 
             /* The number of sections of this node's size */
-            UINT64DECODE_VAR(p, node_count, sect_cnt_size);
+            UINT64DECODE_VAR(image, node_count, sect_cnt_size);
             HDassert(node_count);
 
             /* The size of the sections for this node */
-            UINT64DECODE_VAR(p, sect_size, sinfo->sect_len_size);
+            UINT64DECODE_VAR(image, sect_size, sinfo->sect_len_size);
             HDassert(sect_size);
 
             /* Loop over nodes of this size */
@@ -646,324 +901,306 @@ H5FS_cache_sinfo_load(H5F_t *f, hid_t dxpl_id, haddr_t H5_ATTR_UNUSED addr, void
                 unsigned des_flags;     /* Flags from deserialize callback */
 
                 /* The address of the section */
-                UINT64DECODE_VAR(p, sect_addr, sinfo->sect_off_size);
+                UINT64DECODE_VAR(image, sect_addr, sinfo->sect_off_size);
 
                 /* The type of this section */
-                sect_type = *p++;
+                sect_type = *image++;
 
                 /* Call 'deserialize' callback for this section */
                 des_flags = 0;
                 HDassert(udata->fspace->sect_cls[sect_type].deserialize);
-                if(NULL == (new_sect = (*udata->fspace->sect_cls[sect_type].deserialize)(&udata->fspace->sect_cls[sect_type], udata->dxpl_id, p, sect_addr, sect_size, &des_flags)))
+                if(NULL == (new_sect = (*fspace->sect_cls[sect_type].deserialize) (&fspace->sect_cls[sect_type], udata->dxpl_id, image, sect_addr, sect_size, &des_flags)))
                     HGOTO_ERROR(H5E_FSPACE, H5E_CANTDECODE, NULL, "can't deserialize section")
 
-                /* Update offset in serialization buffer */
-                p += udata->fspace->sect_cls[sect_type].serial_size;
+                /* Update offset in serialization image */
+                image += udata->fspace->sect_cls[sect_type].serial_size;
 
                 /* Insert section in free space manager, unless requested not to */
                 if(!(des_flags & H5FS_DESERIALIZE_NO_ADD))
                     if(H5FS_sect_add(udata->f, udata->dxpl_id, udata->fspace, new_sect, H5FS_ADD_DESERIALIZING, NULL) < 0)
                         HGOTO_ERROR(H5E_FSPACE, H5E_CANTINSERT, NULL, "can't add section to free space manager")
             } /* end for */
-        } while(p < ((buf + old_sect_size) - H5FS_SIZEOF_CHKSUM));
+        } while(image < (((const uint8_t *)_image + old_sect_size) - H5FS_SIZEOF_CHKSUM));
 
         /* Sanity check */
-        HDassert((size_t)(p - buf) == (old_sect_size - H5FS_SIZEOF_CHKSUM));
-        HDassert(old_sect_size == udata->fspace->sect_size);
-        HDassert(old_tot_sect_count == udata->fspace->tot_sect_count);
-        HDassert(old_serial_sect_count == udata->fspace->serial_sect_count);
-        HDassert(old_ghost_sect_count == udata->fspace->ghost_sect_count);
-        HDassert(old_tot_space == udata->fspace->tot_space);
+        HDassert((size_t)(image - (const uint8_t *)_image) == (old_sect_size - H5FS_SIZEOF_CHKSUM));
+        HDassert(old_sect_size == fspace->sect_size);
+        HDassert(old_tot_sect_count == fspace->tot_sect_count);
+        HDassert(old_serial_sect_count == fspace->serial_sect_count);
+        HDassert(old_ghost_sect_count == fspace->ghost_sect_count);
+        HDassert(old_tot_space == fspace->tot_space);
     } /* end if */
 
     /* Compute checksum on indirect block */
-    computed_chksum = H5_checksum_metadata(buf, (size_t)(p - (const uint8_t *)buf), 0);
+    computed_chksum = H5_checksum_metadata((const uint8_t *)_image, (size_t)(image - (const uint8_t *)_image), 0);
 
     /* Metadata checksum */
-    UINT32DECODE(p, stored_chksum);
+    UINT32DECODE(image, stored_chksum);
 
     /* Verify checksum */
     if(stored_chksum != computed_chksum)
-	HGOTO_ERROR(H5E_FSPACE, H5E_BADVALUE, NULL, "incorrect metadata checksum for fractal heap indirect block")
+        HGOTO_ERROR(H5E_FSPACE, H5E_BADVALUE, NULL, "incorrect metadata checksum for fractal heap indirect block")
 
     /* Sanity check */
-    HDassert((size_t)(p - (const uint8_t *)buf) == old_sect_size);
+    HDassert((size_t)(image - (const uint8_t *)_image) == old_sect_size);
 
     /* Set return value */
     ret_value = sinfo;
 
 done:
-    if(buf)
-        buf = H5FL_BLK_FREE(sect_block, buf);
     if(!ret_value && sinfo)
         if(H5FS_sinfo_dest(sinfo) < 0)
             HDONE_ERROR(H5E_FSPACE, H5E_CANTFREE, NULL, "unable to destroy free space info")
 
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5FS_cache_sinfo_load() */ /*lint !e818 Can't make udata a pointer to const */
+} /* end H5FS__cache_sinfo_deserialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5FS_sinfo_serialize_sect_cb
+ * Function:    H5FS__cache_sinfo_image_len
  *
- * Purpose:	Skip list iterator callback to serialize free space sections
- *              of a particular size
+ * Purpose:     Compute the size of the data structure on disk and return
+ *              it in *image_len.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Quincey Koziol
- *              Monday, May  8, 2006
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              August 14, 2013
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5FS_sinfo_serialize_sect_cb(void *_item, void H5_ATTR_UNUSED *key, void *_udata)
+H5FS__cache_sinfo_image_len(const void *_thing, size_t *image_len,
+    hbool_t H5_ATTR_UNUSED *compressed_ptr, size_t H5_ATTR_UNUSED *compressed_image_len_ptr)
 {
-    H5FS_section_class_t *sect_cls;     /* Class of section */
-    H5FS_section_info_t *sect= (H5FS_section_info_t *)_item;   /* Free space section to work on */
-    H5FS_iter_ud_t *udata = (H5FS_iter_ud_t *)_udata; /* Callback info */
-    herr_t ret_value = SUCCEED;         /* Return value */
-
-    FUNC_ENTER_NOAPI_NOINIT
-
-    /* Check arguments. */
-    HDassert(sect);
-    HDassert(udata->sinfo);
-    HDassert(udata->p);
+    const H5FS_sinfo_t *sinfo = (const H5FS_sinfo_t *)_thing;   /* Pointer to the object */
+    const H5FS_t *fspace;               /* Free space header */
 
-    /* Get section's class */
-    sect_cls = &udata->sinfo->fspace->sect_cls[sect->type];
-
-    /* Check if this section should be serialized (i.e. is not a ghost section) */
-    if(!(sect_cls->flags & H5FS_CLS_GHOST_OBJ)) {
-        /* The address of the section */
-        UINT64ENCODE_VAR(*udata->p, sect->addr, udata->sinfo->sect_off_size);
-
-        /* The type of this section */
-        *(*udata->p)++ = (uint8_t)sect->type;
+    FUNC_ENTER_STATIC_NOERR
 
-        /* Call 'serialize' callback for this section */
-        if(sect_cls->serialize) {
-            if((*sect_cls->serialize)(sect_cls, sect, *udata->p) < 0)
-                HGOTO_ERROR(H5E_FSPACE, H5E_CANTSERIALIZE, FAIL, "can't syncronize section")
+    /* Sanity checks */
+    HDassert(sinfo);
+    HDassert(sinfo->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(sinfo->cache_info.type == H5AC_FSPACE_SINFO);
+    fspace = sinfo->fspace;
+    HDassert(fspace);
+    HDassert(fspace->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(fspace->cache_info.type == H5AC_FSPACE_HDR);
+    HDassert(image_len);
 
-            /* Update offset in serialization buffer */
-            (*udata->p) += sect_cls->serial_size;
-        } /* end if */
-        else
-            HDassert(sect_cls->serial_size == 0);
-    } /* end if */
+    /* Set the image length size */
+    H5_CHECKED_ASSIGN(*image_len, size_t, sinfo->fspace->alloc_sect_size, hsize_t);
 
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* H5FS_sinfo_serialize_sect_cb() */
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5FS__cache_sinfo_image_len() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5FS_sinfo_serialize_node_cb
+ * Function:	H5FS__cache_sinfo_pre_serialize
  *
- * Purpose:	Skip list iterator callback to serialize free space sections
- *              in a bin
+ * Purpose:	The objective of this function is to test to see if file space 
+ *		for the section info is located in temporary (AKA imaginary) file 
+ *		space.  If it is, relocate file space for the section info to 
+ *		regular file space.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:	Success:	SUCCEED
+ *		Failure:	FAIL
  *
- * Programmer:	Quincey Koziol
- *              Monday, May  8, 2006
+ * Programmer:	John Mainzer
+ *		7/7/14
  *
  *-------------------------------------------------------------------------
  */
-static herr_t
-H5FS_sinfo_serialize_node_cb(void *_item, void H5_ATTR_UNUSED *key, void *_udata)
+static herr_t 
+H5FS__cache_sinfo_pre_serialize(const H5F_t *f, hid_t dxpl_id, void *_thing,
+    haddr_t addr, size_t len, size_t H5_ATTR_UNUSED compressed_len, haddr_t *new_addr,
+    size_t *new_len, size_t H5_ATTR_UNUSED *new_compressed_len, unsigned *flags)
 {
-    H5FS_node_t *fspace_node = (H5FS_node_t *)_item;   /* Free space size node to work on */
-    H5FS_iter_ud_t *udata = (H5FS_iter_ud_t *)_udata; /* Callback info */
-    herr_t ret_value = SUCCEED;         /* Return value */
+    H5FS_sinfo_t 	*sinfo = (H5FS_sinfo_t *)_thing;        /* Pointer to the object */
+    H5FS_t 		*fspace;                /* Free space header */
+    haddr_t             sinfo_addr;             /* Address for section info */
+    herr_t              ret_value = SUCCEED;    /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
-    /* Check arguments. */
-    HDassert(fspace_node);
-    HDassert(udata->sinfo);
-    HDassert(udata->p);
+    /* Sanity checks */
+    HDassert(f);
+    HDassert(sinfo);
+    HDassert(sinfo->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(sinfo->cache_info.type == H5AC_FSPACE_SINFO);
+    fspace = sinfo->fspace;
+    HDassert(fspace->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(fspace->cache_info.type == H5AC_FSPACE_HDR);
+    HDassert(fspace->cache_info.is_pinned);
+    HDassert(H5F_addr_defined(addr));
+    HDassert(H5F_addr_eq(fspace->sect_addr, addr));
+    HDassert(fspace->sect_size == len);
+    HDassert(new_addr);
+    HDassert(new_len);
+    HDassert(flags);
 
-    /* Check if this node has any serializable sections */
-    if(fspace_node->serial_count > 0) {
-        /* The number of serializable sections of this node's size */
-        UINT64ENCODE_VAR(*udata->p, fspace_node->serial_count, udata->sect_cnt_size);
+    /* we shouldn't be called if the section info is empty */
+    HDassert(fspace->serial_sect_count > 0);
 
-        /* The size of the sections for this node */
-        UINT64ENCODE_VAR(*udata->p, fspace_node->sect_size, udata->sinfo->sect_len_size);
+    sinfo_addr = addr; /* this will change if we relocate the section data */
 
-        /* Iterate through all the sections of this size */
-        HDassert(fspace_node->sect_list);
-        if(H5SL_iterate(fspace_node->sect_list, H5FS_sinfo_serialize_sect_cb, udata) < 0)
-            HGOTO_ERROR(H5E_FSPACE, H5E_BADITER, FAIL, "can't iterate over section nodes")
+    /* Check for section info at temporary address */
+    if(H5F_IS_TMP_ADDR(f, fspace->sect_addr)) {
+        /* Sanity check */
+        HDassert(fspace->sect_size > 0);
+        HDassert(H5F_addr_eq(fspace->sect_addr, addr));
+
+        /* Allocate space for the section info in file */
+        if(HADDR_UNDEF == (sinfo_addr = H5MF_alloc((H5F_t *)f, H5FD_MEM_FSPACE_SINFO, dxpl_id, fspace->sect_size)))
+            HGOTO_ERROR(H5E_FSPACE, H5E_NOSPACE, FAIL, "file allocation failed for free space sections")
+
+        fspace->alloc_sect_size = (size_t)fspace->sect_size;
+
+        /* Sanity check */
+        HDassert(!H5F_addr_eq(sinfo->fspace->sect_addr, sinfo_addr));
+
+        /* Let the metadata cache know the section info moved */
+        if(H5AC_move_entry((H5F_t *)f, H5AC_FSPACE_SINFO, sinfo->fspace->sect_addr, sinfo_addr) < 0)
+            HGOTO_ERROR(H5E_FSPACE, H5E_CANTMOVE, FAIL, "unable to move section info")
+
+        /* Update the internal address for the section info */
+        sinfo->fspace->sect_addr = sinfo_addr;
+
+        /* Mark free space header as dirty */
+        if(H5AC_mark_entry_dirty(fspace) < 0)
+            HGOTO_ERROR(H5E_FSPACE, H5E_CANTMARKDIRTY, FAIL, "unable to mark free space header as dirty")
+    } /* end if */
+
+    if(!H5F_addr_eq(addr, sinfo_addr)) {
+        *new_addr = sinfo_addr;
+        *flags = H5C__SERIALIZE_MOVED_FLAG;
     } /* end if */
+    else
+        *flags = 0;
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* H5FS_sinfo_serialize_node_cb() */
+} /* end H5FS__cache_sinfo_pre_serialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5FS_cache_sinfo_flush
+ * Function:	H5FS__cache_sinfo_serialize
  *
- * Purpose:	Flushes a dirty free space section info to disk.
+ * Purpose:	Given an instance of H5FS_sinfo_t and a suitably sized buffer,
+ *		serialize the contents of the instance of H5FS_sinfo_t and write 
+ *		its contents to the buffer.  This buffer will be used to write 
+ *		the image of the instance to file.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:	Success:	SUCCEED
+ *		Failure:	FAIL
  *
- * Programmer:  Quincey Koziol
- *              koziol@ncsa.uiuc.edu
- *              July 31 2006
+ * Programmer:	John Mainzer
+ *		6/21/14
  *
  *-------------------------------------------------------------------------
  */
-static herr_t
-H5FS_cache_sinfo_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5FS_sinfo_t *sinfo, unsigned H5_ATTR_UNUSED * flags_ptr)
+static herr_t 
+H5FS__cache_sinfo_serialize(const H5F_t *f, void *_image, size_t len,
+    void *_thing)
 {
-    herr_t ret_value = SUCCEED;         /* Return value */
+    H5FS_sinfo_t        *sinfo = (H5FS_sinfo_t *)_thing;        /* Pointer to the object */
+    H5FS_t              *fspace;            /* Free space header */
+    H5FS_iter_ud_t      udata;              /* User data for callbacks */
+    uint8_t             *image = (uint8_t *)_image;     /* Pointer into raw data buffer */
+    uint32_t            metadata_chksum;    /* Computed metadata checksum value */
+    unsigned            bin;                /* Current bin we are on */
+    herr_t              ret_value = SUCCEED; /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
-    /* check arguments */
+    /* Sanity checks */
     HDassert(f);
-    HDassert(H5F_addr_defined(addr));
+    HDassert(image);
     HDassert(sinfo);
-    HDassert(sinfo->fspace);
-    HDassert(sinfo->fspace->sect_cls);
-
-    if(sinfo->cache_info.is_dirty || sinfo->dirty) {
-        H5FS_iter_ud_t udata;       /* User data for callbacks */
-        uint8_t	*buf = NULL;        /* Temporary raw data buffer */
-        uint8_t *p;                 /* Pointer into raw data buffer */
-        uint32_t metadata_chksum;   /* Computed metadata checksum value */
-        unsigned bin;               /* Current bin we are on */
-
-        /* Sanity check address */
-        if(H5F_addr_ne(addr, sinfo->fspace->sect_addr))
-            HGOTO_ERROR(H5E_FSPACE, H5E_CANTLOAD, FAIL, "incorrect address for free space sections")
+    HDassert(sinfo->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(sinfo->cache_info.type == H5AC_FSPACE_SINFO);
+    fspace = sinfo->fspace;
+    HDassert(fspace->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(fspace->cache_info.type == H5AC_FSPACE_HDR);
+    HDassert(fspace->cache_info.is_pinned);
+    HDassert(fspace->sect_size == len);
+    HDassert(fspace->sect_cls);
 
-        /* Allocate temporary buffer */
-        if((buf = H5FL_BLK_MALLOC(sect_block, (size_t)sinfo->fspace->sect_size)) == NULL)
-            HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed")
-
-        p = buf;
-
-        /* Magic number */
-        HDmemcpy(p, H5FS_SINFO_MAGIC, (size_t)H5_SIZEOF_MAGIC);
-        p += H5_SIZEOF_MAGIC;
-
-        /* Version # */
-        *p++ = H5FS_SINFO_VERSION;
-
-        /* Address of free space header for these sections */
-        H5F_addr_encode(f, &p, sinfo->fspace->addr);
-
-        /* Set up user data for iterator */
-        udata.sinfo = sinfo;
-        udata.p = &p;
-        udata.sect_cnt_size = H5VM_limit_enc_size((uint64_t)sinfo->fspace->serial_sect_count);
-
-        /* Iterate over all the bins */
-        for(bin = 0; bin < sinfo->nbins; bin++)
-            /* Check if there are any sections in this bin */
-            if(sinfo->bins[bin].bin_list)
-                /* Iterate over list of section size nodes for bin */
-                if(H5SL_iterate(sinfo->bins[bin].bin_list, H5FS_sinfo_serialize_node_cb, &udata) < 0)
-                    HGOTO_ERROR(H5E_FSPACE, H5E_BADITER, FAIL, "can't iterate over section size nodes")
-
-        /* Compute checksum */
-        metadata_chksum = H5_checksum_metadata(buf, (size_t)(p - buf), 0);
-
-        /* Metadata checksum */
-        UINT32ENCODE(p, metadata_chksum);
-
-        /* Sanity check */
-        HDassert((size_t)(p - buf) == sinfo->fspace->sect_size);
-        HDassert(sinfo->fspace->sect_size <= sinfo->fspace->alloc_sect_size);
-
-        /* Check for section info at temporary address */
-        if(H5F_IS_TMP_ADDR(f, sinfo->fspace->sect_addr)) {
-            /* Sanity check */
-            HDassert(sinfo->fspace->sect_size > 0);
-            HDassert(H5F_addr_eq(sinfo->fspace->sect_addr, addr));
-
-            /* Allocate space for the section info in file */
-            if(HADDR_UNDEF == (addr = H5MF_alloc(f, H5FD_MEM_FSPACE_SINFO, dxpl_id, sinfo->fspace->sect_size)))
-                HGOTO_ERROR(H5E_FSPACE, H5E_NOSPACE, FAIL, "file allocation failed for free space sections")
-            sinfo->fspace->alloc_sect_size = (size_t)sinfo->fspace->sect_size;
+    /* Magic number */
+    HDmemcpy(image, H5FS_SINFO_MAGIC, (size_t)H5_SIZEOF_MAGIC);
+    image += H5_SIZEOF_MAGIC;
 
-            /* Sanity check */
-            HDassert(!H5F_addr_eq(sinfo->fspace->sect_addr, addr));
+    /* Version # */
+    *image++ = H5FS_SINFO_VERSION;
 
-            /* Let the metadata cache know the section info moved */
-            if(H5AC_move_entry(f, H5AC_FSPACE_SINFO, sinfo->fspace->sect_addr, addr) < 0)
-                HGOTO_ERROR(H5E_HEAP, H5E_CANTMOVE, FAIL, "unable to move indirect block")
+    /* Address of free space header for these sections */
+    H5F_addr_encode(f, &image, sinfo->fspace->addr);
 
-            /* Update the internal address for the section info */
-            sinfo->fspace->sect_addr = addr;
+    /* Set up user data for iterator */
+    udata.sinfo = sinfo;
+    udata.image = &image;
+    udata.sect_cnt_size = H5VM_limit_enc_size((uint64_t)sinfo->fspace->serial_sect_count);
 
-            /* Mark free space header as dirty */
-            if(H5AC_mark_entry_dirty(sinfo->fspace) < 0)
-                HGOTO_ERROR(H5E_FSPACE, H5E_CANTMARKDIRTY, FAIL, "unable to mark free space header as dirty")
-        } /* end if */
+    /* Iterate over all the bins */
+    for(bin = 0; bin < sinfo->nbins; bin++)
+        /* Check if there are any sections in this bin */
+        if(sinfo->bins[bin].bin_list)
+            /* Iterate over list of section size nodes for bin */
+            if(H5SL_iterate(sinfo->bins[bin].bin_list, H5FS__sinfo_serialize_node_cb, &udata) < 0)
+                HGOTO_ERROR(H5E_FSPACE, H5E_BADITER, FAIL, "can't iterate over section size nodes")
 
-        /* Write buffer to disk */
-        if(H5F_block_write(f, H5FD_MEM_FSPACE_SINFO, sinfo->fspace->sect_addr, (size_t)sinfo->fspace->sect_size, dxpl_id, buf) < 0)
-            HGOTO_ERROR(H5E_FSPACE, H5E_CANTFLUSH, FAIL, "unable to save free space sections to disk")
 
-        buf = H5FL_BLK_FREE(sect_block, buf);
+    /* Compute checksum */
+    metadata_chksum = H5_checksum_metadata(_image, (size_t)(image - (uint8_t *)_image), 0);
 
-	sinfo->cache_info.is_dirty = FALSE;
-        sinfo->dirty = FALSE;
-    } /* end if */
+    /* Metadata checksum */
+    UINT32ENCODE(image, metadata_chksum);
 
-    if(destroy)
-        if(H5FS_cache_sinfo_dest(f, sinfo) < 0)
-	    HGOTO_ERROR(H5E_FSPACE, H5E_CANTFREE, FAIL, "unable to destroy free space section info")
+    /* Sanity check */
+    HDassert((size_t)(image - (uint8_t *)_image) == sinfo->fspace->sect_size);
+    HDassert(sinfo->fspace->sect_size <= sinfo->fspace->alloc_sect_size);
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* H5FS_cache_sinfo_flush() */
+} /* end H5FS__cache_sinfo_serialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5FS_cache_sinfo_dest
+ * Function:	H5FS__cache_sinfo_free_icr
  *
- * Purpose:	Destroys a free space section info in memory.
+ * Purpose:	Free the memory used for the in core representation of the 
+ *		free space manager section info.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Note:	The metadata cache sets the object's cache_info.magic to
+ *		H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC before calling a free_icr
+ *		callback (checked in assert).
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		July 31 2006
+ * Return:	Success:	SUCCEED
+ *		Failure:	FAIL
+ *
+ * Programmer:	John Mainzer
+ *		6/21/14
  *
  *-------------------------------------------------------------------------
  */
-static herr_t
-H5FS_cache_sinfo_dest(H5F_t *f, H5FS_sinfo_t *sinfo)
+static herr_t 
+H5FS__cache_sinfo_free_icr(void *_thing)
 {
-    herr_t ret_value = SUCCEED; /* Return value */
+    H5FS_sinfo_t        *sinfo = (H5FS_sinfo_t *)_thing;    /* Pointer to the object */
+    H5FS_t              *fspace;                /* Free space header */
+    herr_t              ret_value = SUCCEED;    /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
-    /* Check arguments */
+    /* Sanity checks */
     HDassert(sinfo);
-
-    /* If we're going to free the space on disk, the address must be valid */
-    HDassert(!sinfo->cache_info.free_file_space_on_destroy || H5F_addr_defined(sinfo->cache_info.addr));
-
-    /* Check for freeing file space for free space section info */
-    if(sinfo->cache_info.free_file_space_on_destroy) {
-        /* Sanity check */
-        HDassert(sinfo->fspace->alloc_sect_size > 0);
-
-        /* Release the space on disk */
-        /* (XXX: Nasty usage of internal DXPL value! -QAK) */
-        if(!H5F_IS_TMP_ADDR(f, sinfo->cache_info.addr))
-            if(H5MF_xfree(f, H5FD_MEM_FSPACE_SINFO, H5AC_dxpl_id, sinfo->cache_info.addr, (hsize_t)sinfo->fspace->alloc_sect_size) < 0)
-                HGOTO_ERROR(H5E_FSPACE, H5E_CANTFREE, FAIL, "unable to free free space section info")
-    } /* end if */
+    HDassert(sinfo->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC);
+    HDassert(sinfo->cache_info.type == H5AC_FSPACE_SINFO);
+    fspace = sinfo->fspace;
+    HDassert(fspace->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(fspace->cache_info.type == H5AC_FSPACE_HDR);
+    HDassert(fspace->cache_info.is_pinned);
 
     /* Destroy free space info */
     if(H5FS_sinfo_dest(sinfo) < 0)
@@ -971,73 +1208,107 @@ H5FS_cache_sinfo_dest(H5F_t *f, H5FS_sinfo_t *sinfo)
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5FS_cache_sinfo_dest() */
+} /* end H5FS__cache_sinfo_free_icr() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5FS_cache_sinfo_clear
+ * Function:	H5FS__sinfo_serialize_sect_cb
  *
- * Purpose:	Mark a free space section info in memory as non-dirty.
+ * Purpose:	Skip list iterator callback to serialize free space sections
+ *              of a particular size
  *
  * Return:	Non-negative on success/Negative on failure
  *
  * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		July 31 2006
+ *              Monday, May  8, 2006
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5FS_cache_sinfo_clear(H5F_t *f, H5FS_sinfo_t *sinfo, hbool_t destroy)
+H5FS__sinfo_serialize_sect_cb(void *_item, void H5_ATTR_UNUSED *key, void *_udata)
 {
+    H5FS_section_class_t *sect_cls;     /* Class of section */
+    H5FS_section_info_t *sect= (H5FS_section_info_t *)_item;   /* Free space section to work on */
+    H5FS_iter_ud_t *udata = (H5FS_iter_ud_t *)_udata; /* Callback info */
     herr_t ret_value = SUCCEED;         /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
-    /*
-     * Check arguments.
-     */
-    HDassert(sinfo);
+    /* Check arguments. */
+    HDassert(sect);
+    HDassert(udata->sinfo);
+    HDassert(udata->image);
 
-    /* Reset the dirty flag.  */
-    sinfo->cache_info.is_dirty = FALSE;
+    /* Get section's class */
+    sect_cls = &udata->sinfo->fspace->sect_cls[sect->type];
 
-    if(destroy)
-        if(H5FS_cache_sinfo_dest(f, sinfo) < 0)
-	    HGOTO_ERROR(H5E_FSPACE, H5E_CANTFREE, FAIL, "unable to destroy free space section info")
+    /* Check if this section should be serialized (i.e. is not a ghost section) */
+    if(!(sect_cls->flags & H5FS_CLS_GHOST_OBJ)) {
+        /* The address of the section */
+        UINT64ENCODE_VAR(*udata->image, sect->addr, udata->sinfo->sect_off_size);
+
+        /* The type of this section */
+        *(*udata->image)++ = (uint8_t)sect->type;
+
+        /* Call 'serialize' callback for this section */
+        if(sect_cls->serialize) {
+            if((*sect_cls->serialize)(sect_cls, sect, *udata->image) < 0)
+                HGOTO_ERROR(H5E_FSPACE, H5E_CANTSERIALIZE, FAIL, "can't syncronize section")
+
+            /* Update offset in serialization buffer */
+            (*udata->image) += sect_cls->serial_size;
+        } /* end if */
+        else
+            HDassert(sect_cls->serial_size == 0);
+    } /* end if */
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5FS_cache_sinfo_clear() */
+} /* H5FS__sinfo_serialize_sect_cb() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5FS_cache_sinfo_size
+ * Function:	H5FS__sinfo_serialize_node_cb
  *
- * Purpose:	Compute the size in bytes of a free space section info
- *		on disk, and return it in *size_ptr.  On failure,
- *		the value of *size_ptr is undefined.
+ * Purpose:	Skip list iterator callback to serialize free space sections
+ *              in a bin
  *
  * Return:	Non-negative on success/Negative on failure
  *
  * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		July 31 2006
+ *              Monday, May  8, 2006
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5FS_cache_sinfo_size(const H5F_t H5_ATTR_UNUSED *f, const H5FS_sinfo_t *sinfo, size_t *size_ptr)
+H5FS__sinfo_serialize_node_cb(void *_item, void H5_ATTR_UNUSED *key, void *_udata)
 {
-    FUNC_ENTER_NOAPI_NOINIT_NOERR
+    H5FS_node_t *fspace_node = (H5FS_node_t *)_item;   /* Free space size node to work on */
+    H5FS_iter_ud_t *udata = (H5FS_iter_ud_t *)_udata; /* Callback info */
+    herr_t ret_value = SUCCEED;         /* Return value */
 
-    /* check arguments */
-    HDassert(sinfo);
-    HDassert(size_ptr);
+    FUNC_ENTER_STATIC
+
+    /* Check arguments. */
+    HDassert(fspace_node);
+    HDassert(udata->sinfo);
+    HDassert(udata->image);
 
-    /* Set size value */
-    H5_CHECKED_ASSIGN(*size_ptr, size_t, sinfo->fspace->alloc_sect_size, hsize_t);
+    /* Check if this node has any serializable sections */
+    if(fspace_node->serial_count > 0) {
+        /* The number of serializable sections of this node's size */
+        UINT64ENCODE_VAR(*udata->image, fspace_node->serial_count, udata->sect_cnt_size);
 
-    FUNC_LEAVE_NOAPI(SUCCEED)
-} /* H5FS_cache_sinfo_size() */
+        /* The size of the sections for this node */
+        UINT64ENCODE_VAR(*udata->image, fspace_node->sect_size, udata->sinfo->sect_len_size);
+
+        /* Iterate through all the sections of this size */
+        HDassert(fspace_node->sect_list);
+        if(H5SL_iterate(fspace_node->sect_list, H5FS__sinfo_serialize_sect_cb, udata) < 0)
+            HGOTO_ERROR(H5E_FSPACE, H5E_BADITER, FAIL, "can't iterate over section nodes")
+    } /* end if */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5FS__sinfo_serialize_node_cb() */
 
diff --git a/src/H5FSdbg.c b/src/H5FSdbg.c
index b180efd..de66ebd 100644
--- a/src/H5FSdbg.c
+++ b/src/H5FSdbg.c
@@ -121,7 +121,7 @@ H5FS_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE *stream, int indent, int
     /*
      * Load the free space header.
      */
-    if(NULL == (fspace = (H5FS_t *)H5AC_protect(f, dxpl_id, H5AC_FSPACE_HDR, addr, &cache_udata, H5AC_READ)))
+    if(NULL == (fspace = (H5FS_t *)H5AC_protect(f, dxpl_id, H5AC_FSPACE_HDR, addr, &cache_udata, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_FSPACE, H5E_CANTLOAD, FAIL, "unable to load free space header")
 
     /* Print opening message */
@@ -263,7 +263,7 @@ H5FS_sects_debug(H5F_t *f, hid_t dxpl_id, haddr_t H5_ATTR_UNUSED addr, FILE *str
     /*
      * Load the free space header.
      */
-    if(NULL == (fspace = (H5FS_t *)H5AC_protect(f, dxpl_id, H5AC_FSPACE_HDR, fs_addr, &cache_udata, H5AC_READ)))
+    if(NULL == (fspace = (H5FS_t *)H5AC_protect(f, dxpl_id, H5AC_FSPACE_HDR, fs_addr, &cache_udata, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_FSPACE, H5E_CANTLOAD, FAIL, "unable to load free space header")
 
     /* Retrieve the client id */
diff --git a/src/H5FSpkg.h b/src/H5FSpkg.h
index 78afde8..2c1eba7 100644
--- a/src/H5FSpkg.h
+++ b/src/H5FSpkg.h
@@ -182,7 +182,9 @@ struct H5FS_t {
     unsigned sinfo_lock_count;  /* # of times the section info has been locked */
     hbool_t sinfo_protected;    /* Whether the section info was protected when locked */
     hbool_t sinfo_modified;     /* Whether the section info has been modified while locked */
-    H5AC_protect_t sinfo_accmode; /* Access mode for protecting the section info */
+    unsigned sinfo_accmode;     /* Access mode for protecting the section info */
+                                /* must be either H5C__NO_FLAGS_SET (i.e r/w)  */
+				/* or H5AC__READ_ONLY_FLAG (i.e. r/o).         */
     size_t max_cls_serial_size; /* Max. additional size of serialized form of section */
     hsize_t    threshold;      	/* Threshold for alignment              */
     hsize_t    alignment;      	/* Alignment                            */
diff --git a/src/H5FSsection.c b/src/H5FSsection.c
index 8fe4075..0b47f51 100644
--- a/src/H5FSsection.c
+++ b/src/H5FSsection.c
@@ -204,7 +204,7 @@ done:
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5FS_sinfo_lock(H5F_t *f, hid_t dxpl_id, H5FS_t *fspace, H5AC_protect_t accmode)
+H5FS_sinfo_lock(H5F_t *f, hid_t dxpl_id, H5FS_t *fspace, unsigned accmode)
 {
     H5FS_sinfo_cache_ud_t cache_udata; /* User-data for cache callback */
     herr_t ret_value = SUCCEED;    /* Return value */
@@ -220,14 +220,21 @@ HDfprintf(stderr, "%s: fspace->alloc_sect_size = %Hu, fspace->sect_size = %Hu\n"
     HDassert(f);
     HDassert(fspace);
 
+    /* only H5AC__READ_ONLY_FLAG may appear in accmode */
+    HDassert((accmode & (unsigned)(~H5AC__READ_ONLY_FLAG)) == 0);
+
     /* If the free space header doesn't already "own" the section info, load
      *  section info or create it
      */
     if(fspace->sinfo) {
         /* Check if the section info was protected & we want a different access mode */
+
+        /* only H5AC__READ_ONLY_FLAG may appear in fspace->sinfo_accmode */
+        HDassert(((fspace->sinfo_accmode) & (unsigned)(~H5AC__READ_ONLY_FLAG)) == 0);
+
         if(fspace->sinfo_protected && accmode != fspace->sinfo_accmode) {
             /* Check if we need to switch from read-only access to read-write */
-            if(H5AC_WRITE == accmode) {
+	    if(0 == (accmode & (unsigned)(~H5AC__READ_ONLY_FLAG))) {
                 /* Unprotect the read-only section info */
                 if(H5AC_unprotect(f, dxpl_id, H5AC_FSPACE_SINFO, fspace->sect_addr, fspace->sinfo, H5AC__NO_FLAGS_SET) < 0)
                     HGOTO_ERROR(H5E_FSPACE, H5E_CANTUNPROTECT, FAIL, "unable to release free space section info")
@@ -236,11 +243,11 @@ HDfprintf(stderr, "%s: fspace->alloc_sect_size = %Hu, fspace->sect_size = %Hu\n"
                 cache_udata.f = f;
                 cache_udata.dxpl_id = dxpl_id;
                 cache_udata.fspace = fspace;
-                if(NULL == (fspace->sinfo = (H5FS_sinfo_t *)H5AC_protect(f, dxpl_id, H5AC_FSPACE_SINFO, fspace->sect_addr, &cache_udata, H5AC_WRITE)))
+                if(NULL == (fspace->sinfo = (H5FS_sinfo_t *)H5AC_protect(f, dxpl_id, H5AC_FSPACE_SINFO, fspace->sect_addr, &cache_udata, H5AC__NO_FLAGS_SET)))
                     HGOTO_ERROR(H5E_FSPACE, H5E_CANTPROTECT, FAIL, "unable to load free space sections")
 
                 /* Switch the access mode we have */
-                fspace->sinfo_accmode = H5AC_WRITE;
+                fspace->sinfo_accmode = H5AC__NO_FLAGS_SET;
             } /* end if */
         } /* end if */
     } /* end if */
@@ -331,7 +338,7 @@ HDfprintf(stderr, "%s: fspace->alloc_sect_size = %Hu, fspace->sect_size = %Hu\n"
     /* Check if we modified any section */
     if(modified) {
         /* Check if the section info was protected with a different access mode */
-        if(fspace->sinfo_protected && fspace->sinfo_accmode != H5AC_WRITE)
+        if(fspace->sinfo_protected && (0 != ((fspace->sinfo_accmode) & H5AC__READ_ONLY_FLAG)))
             HGOTO_ERROR(H5E_FSPACE, H5E_CANTDIRTY, FAIL, "attempt to modify read-only section info")
 
         /* If we modified the section info, mark it dirty */
@@ -915,7 +922,7 @@ H5FS_sect_remove(H5F_t *f, hid_t dxpl_id, H5FS_t *fspace,
     HDassert(sect);
 
     /* Get a pointer to the section info */
-    if(H5FS_sinfo_lock(f, dxpl_id, fspace, H5AC_WRITE) < 0)
+    if(H5FS_sinfo_lock(f, dxpl_id, fspace, H5AC__NO_FLAGS_SET) < 0)
         HGOTO_ERROR(H5E_FSPACE, H5E_CANTGET, FAIL, "can't get section info")
     sinfo_valid = TRUE;
 
@@ -1396,7 +1403,7 @@ HDfprintf(stderr, "%s: *sect = {%a, %Hu, %u, %s}\n", FUNC, sect->addr, sect->siz
     HDassert(sect->size);
 
     /* Get a pointer to the section info */
-    if(H5FS_sinfo_lock(f, dxpl_id, fspace, H5AC_WRITE) < 0)
+    if(H5FS_sinfo_lock(f, dxpl_id, fspace, H5AC__NO_FLAGS_SET) < 0)
         HGOTO_ERROR(H5E_FSPACE, H5E_CANTGET, FAIL, "can't get section info")
     sinfo_valid = TRUE;
 
@@ -1494,7 +1501,7 @@ HDfprintf(stderr, "%s: fspace->ghost_sect_count = %Hu\n", FUNC, fspace->ghost_se
         H5FS_section_info_t *sect;      /* Temporary free space section */
 
         /* Get a pointer to the section info */
-        if(H5FS_sinfo_lock(f, dxpl_id, fspace, H5AC_WRITE) < 0)
+        if(H5FS_sinfo_lock(f, dxpl_id, fspace, H5AC__NO_FLAGS_SET) < 0)
             HGOTO_ERROR(H5E_FSPACE, H5E_CANTGET, FAIL, "can't get section info")
         sinfo_valid = TRUE;
 
@@ -1613,7 +1620,7 @@ H5FS_sect_try_merge(H5F_t *f, hid_t dxpl_id, H5FS_t *fspace, H5FS_section_info_t
     HDassert(sect->size);
 
     /* Get a pointer to the section info */
-    if(H5FS_sinfo_lock(f, dxpl_id, fspace, H5AC_WRITE) < 0)
+    if(H5FS_sinfo_lock(f, dxpl_id, fspace, H5AC__NO_FLAGS_SET) < 0)
 	HGOTO_ERROR(H5E_FSPACE, H5E_CANTGET, FAIL, "can't get section info")
     sinfo_valid = TRUE;
     saved_fs_size = sect->size;
@@ -1849,7 +1856,7 @@ HDfprintf(stderr, "%s: fspace->ghost_sect_count = %Hu\n", FUNC, fspace->ghost_se
 #endif /* QAK */
     if(fspace->tot_sect_count > 0) {
         /* Get a pointer to the section info */
-        if(H5FS_sinfo_lock(f, dxpl_id, fspace, H5AC_WRITE) < 0)
+        if(H5FS_sinfo_lock(f, dxpl_id, fspace, H5AC__NO_FLAGS_SET) < 0)
             HGOTO_ERROR(H5E_FSPACE, H5E_CANTGET, FAIL, "can't get section info")
         sinfo_valid = TRUE;
 
@@ -1997,7 +2004,7 @@ HDfprintf(stderr, "%s: fspace->tot_sect_count = %Hu\n", FUNC, fspace->tot_sect_c
         unsigned bin;           /* Current bin we are on */
 
         /* Get a pointer to the section info */
-        if(H5FS_sinfo_lock(f, dxpl_id, fspace, H5AC_READ) < 0)
+        if(H5FS_sinfo_lock(f, dxpl_id, fspace, H5AC__READ_ONLY_FLAG) < 0)
             HGOTO_ERROR(H5E_FSPACE, H5E_CANTGET, FAIL, "can't get section info")
         sinfo_valid = TRUE;
 
@@ -2089,7 +2096,7 @@ H5FS_sect_change_class(H5F_t *f, hid_t dxpl_id, H5FS_t *fspace,
     HDassert(new_class < fspace->nclasses);
 
     /* Get a pointer to the section info */
-    if(H5FS_sinfo_lock(f, dxpl_id, fspace, H5AC_WRITE) < 0)
+    if(H5FS_sinfo_lock(f, dxpl_id, fspace, H5AC__NO_FLAGS_SET) < 0)
         HGOTO_ERROR(H5E_FSPACE, H5E_CANTGET, FAIL, "can't get section info")
     sinfo_valid = TRUE;
 
@@ -2403,7 +2410,7 @@ H5FS_sect_try_shrink_eoa(const H5F_t *f, hid_t dxpl_id, const H5FS_t *fspace, vo
     /* Check arguments. */
     HDassert(fspace);
 
-    if(H5FS_sinfo_lock(f, dxpl_id, fspace, H5AC_WRITE) < 0)
+    if(H5FS_sinfo_lock(f, dxpl_id, fspace, H5AC__NO_FLAGS_SET) < 0)
         HGOTO_ERROR(H5E_FSPACE, H5E_CANTGET, FAIL, "can't get section info")
     sinfo_valid = TRUE;
 
diff --git a/src/H5Fint.c b/src/H5Fint.c
index df8e886..0e77349 100644
--- a/src/H5Fint.c
+++ b/src/H5Fint.c
@@ -803,6 +803,14 @@ H5F_dest(H5F_t *f, hid_t dxpl_id, hbool_t flush)
                         HDONE_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "unable to flush cache")
             } /* end if */
 
+            /* if it exists, unpin the driver information block cache entry,
+             * since we're about to destroy the cache 
+             */
+            if(f->shared->drvinfo)
+                if(H5AC_unpin_entry(f->shared->drvinfo) < 0)
+                    /* Push error, but keep going*/
+                    HDONE_ERROR(H5E_FSPACE, H5E_CANTUNPIN, FAIL, "unable to unpin drvinfo")
+
             /* Unpin the superblock, since we're about to destroy the cache */
             if(H5AC_unpin_entry(f->shared->sblock) < 0)
                 /* Push error, but keep going*/
diff --git a/src/H5Fpkg.h b/src/H5Fpkg.h
index 9f70e12..175fa88 100644
--- a/src/H5Fpkg.h
+++ b/src/H5Fpkg.h
@@ -81,6 +81,21 @@
 #define H5F_SUPERBLOCK_FIXED_SIZE ( H5F_SIGNATURE_LEN                   \
         + 1) /* superblock version */
 
+/* The H5F_SUPERBLOCK_MINIMAL_VARLEN_SIZE is the minimal amount of super block
+ * variable length data guarnateed to load the sizeof offsets and the sizeof 
+ * lengths fields in all versions of the superblock.
+ *
+ * This is necessary in the V3 cache, as on the initial load, we need to 
+ * get enough of the superblock to determine its version and size so that
+ * the metadata cache can load the correct amount of data from file to 
+ * allow the second deserialization attempt to succeed.
+ *
+ * The value selected will have to be revisited for each new version 
+ * of the super block.  Note that the current value is one byte larger
+ * than it needs to be. 
+ */
+#define H5F_SUPERBLOCK_MINIMAL_VARLEN_SIZE	7
+
 /* Macros for computing variable-size superblock size */
 #define H5F_SUPERBLOCK_VARLEN_SIZE_COMMON                               \
         (2  /* freespace, and root group versions */			\
@@ -113,20 +128,38 @@
         + (sizeof_addr) /* EOF address */                               \
         + (sizeof_addr) /* root group object header address */          \
         + H5F_SIZEOF_CHKSUM) /* superblock checksum (keep this last) */
-#define H5F_SUPERBLOCK_VARLEN_SIZE(v, f) (				\
-        (v == 0 ? H5F_SUPERBLOCK_VARLEN_SIZE_V0(H5F_SIZEOF_ADDR(f), H5F_SIZEOF_SIZE(f)) : 0) \
-        + (v == 1 ? H5F_SUPERBLOCK_VARLEN_SIZE_V1(H5F_SIZEOF_ADDR(f), H5F_SIZEOF_SIZE(f)) : 0) \
-        + (v == 2 ? H5F_SUPERBLOCK_VARLEN_SIZE_V2(H5F_SIZEOF_ADDR(f)) : 0))
+#define H5F_SUPERBLOCK_VARLEN_SIZE(v, sizeof_addr, sizeof_size) (	\
+        (v == 0 ? H5F_SUPERBLOCK_VARLEN_SIZE_V0(sizeof_addr, sizeof_size) : 0) \
+        + (v == 1 ? H5F_SUPERBLOCK_VARLEN_SIZE_V1(sizeof_addr, sizeof_size) : 0) \
+        + (v == 2 ? H5F_SUPERBLOCK_VARLEN_SIZE_V2(sizeof_addr) : 0))
 
 /* Total size of superblock, depends on superblock version */
-#define H5F_SUPERBLOCK_SIZE(v, f) ( H5F_SUPERBLOCK_FIXED_SIZE           \
-        + H5F_SUPERBLOCK_VARLEN_SIZE(v, f))
+#define H5F_SUPERBLOCK_SIZE(s) ( H5F_SUPERBLOCK_FIXED_SIZE              \
+        + H5F_SUPERBLOCK_VARLEN_SIZE((s)->super_vers, (s)->sizeof_addr, (s)->sizeof_size))
 
 
 /* Forward declaration external file cache struct used below (defined in
  * H5Fefc.c) */
 typedef struct H5F_efc_t H5F_efc_t;
 
+/* Structure for passing 'user data' to superblock cache callbacks */
+typedef struct H5F_superblock_cache_ud_t {
+/* IN: */
+    H5F_t *f;               /* Pointer to file */
+    hbool_t ignore_drvrinfo; /* Indicate if the driver info should be ignored */
+/* OUT: */
+    unsigned sym_leaf_k;    /* Symbol table leaf node's 'K' value */
+    unsigned btree_k[H5B_NUM_BTREE_ID]; /* B-tree key values for each type */
+    haddr_t stored_eof;     /* End-of-file in file */
+    hbool_t drvrinfo_removed; /* Indicate if the driver info was removed */
+} H5F_superblock_cache_ud_t;
+
+/* Structure for passing 'user data' to driver info block cache callbacks */
+typedef struct H5F_drvrinfo_cache_ud_t {
+    H5F_t   *f;               /* Pointer to file */
+    haddr_t driver_addr;      /* address of driver info block */
+} H5F_drvrinfo_cache_ud_t;
+
 /* Structure for metadata & "small [raw] data" block aggregation fields */
 struct H5F_blk_aggr_t {
     unsigned long       feature_flag;   /* Feature flag type */
@@ -176,6 +209,8 @@ typedef struct H5F_mtab_t {
 typedef struct H5F_super_t {
     H5AC_info_t cache_info;     /* Cache entry information structure          */
     unsigned    super_vers;     /* Superblock version                         */
+    uint8_t	sizeof_addr;	/* Size of addresses in file                  */
+    uint8_t	sizeof_size;	/* Size of offsets in file                    */
     uint8_t     status_flags;   /* File status flags                          */
     unsigned    sym_leaf_k;     /* Size of leaves in symbol tables            */
     unsigned    btree_k[H5B_NUM_BTREE_ID]; /* B-tree key values for each type */
@@ -197,6 +232,13 @@ typedef struct H5F_super_t {
 struct H5F_file_t {
     H5FD_t	*lf; 		/* Lower level file handle for I/O	*/
     H5F_super_t *sblock;        /* Pointer to (pinned) superblock for file */
+    H5O_drvinfo_t *drvinfo;	/* Pointer to the (pinned) driver info 
+                                 * cache entry.  This field is only defined
+                                 * for older versions of the super block,
+                                 * and then only when a driver information
+                                 * block is present.  At all other times
+                                 * it should be NULL.
+                                 */
     unsigned	nrefs;		/* Ref count for times file is opened	*/
     unsigned	flags;		/* Access Permissions for file          */
     H5F_mtab_t	mtab;		/* File mount table                     */
@@ -283,6 +325,7 @@ H5FL_EXTERN(H5F_t);
 H5FL_EXTERN(H5F_file_t);
 
 H5_DLLVAR const H5AC_class_t H5AC_SUPERBLOCK[1];
+H5_DLLVAR const H5AC_class_t H5AC_DRVRINFO[1];
 
 
 /******************************/
diff --git a/src/H5Fsuper.c b/src/H5Fsuper.c
index 166247a..e83330d 100644
--- a/src/H5Fsuper.c
+++ b/src/H5Fsuper.c
@@ -258,14 +258,21 @@ H5F__super_read(H5F_t *f, hid_t dxpl_id)
 {
     H5P_genplist_t     *dxpl;               /* DXPL object */
     H5F_super_t *       sblock = NULL;      /* Superblock structure */
+    H5F_superblock_cache_ud_t udata;        /* User data for cache callbacks */
+    H5P_genplist_t     *c_plist;            /* File creation property list  */
     unsigned            sblock_flags = H5AC__NO_FLAGS_SET;       /* flags used in superblock unprotect call      */
     haddr_t             super_addr;         /* Absolute address of superblock */
-    H5AC_protect_t      rw;                 /* Read/write permissions for file  */
-    hbool_t             dirtied = FALSE;    /* Bool for sblock protect call                 */
+    haddr_t             eof;                /* End of file address */
+    unsigned      	rw_flags;           /* Read/write permissions for file */
     herr_t              ret_value = SUCCEED; /* Return value */
 
     FUNC_ENTER_PACKAGE_TAG(dxpl_id, H5AC__SUPERBLOCK_TAG, FAIL)
 
+    /* initialize the drvinfo to NULL -- we will overwrite this if there
+     * is a driver information block 
+     */
+    f->shared->drvinfo = NULL;
+
     /* Get the DXPL plist object for DXPL ID */
     if(NULL == (dxpl = (H5P_genplist_t *)H5I_object(dxpl_id)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "can't get property list")
@@ -284,23 +291,358 @@ H5F__super_read(H5F_t *f, hid_t dxpl_id)
     } /* end if */
 
     /* Determine file intent for superblock protect */
-    if(H5F_INTENT(f) & H5F_ACC_RDWR)
-        rw = H5AC_WRITE;
-    else
-        rw = H5AC_READ;
+
+    /* Must tell cache at protect time that the super block is to be
+     * flushed last (and collectively in the parallel case).
+     */
+    rw_flags = H5AC__FLUSH_LAST_FLAG;
+#ifdef H5_HAVE_PARALLEL
+    rw_flags |= H5C__FLUSH_COLLECTIVELY_FLAG;
+#endif /* H5_HAVE_PARALLEL */
+    if(!(H5F_INTENT(f) & H5F_ACC_RDWR))
+        rw_flags |= H5AC__READ_ONLY_FLAG;
+
+    /* Get the shared file creation property list */
+    if(NULL == (c_plist = (H5P_genplist_t *)H5I_object(f->shared->fcpl_id)))
+        HGOTO_ERROR(H5E_FILE, H5E_BADTYPE, FAIL, "can't get property list")
+
+    /* Make certain we can read the fixed-size portion of the superblock */
+    if(H5F__set_eoa(f, H5FD_MEM_SUPER, 
+              H5F_SUPERBLOCK_FIXED_SIZE + H5F_SUPERBLOCK_MINIMAL_VARLEN_SIZE) < 0)
+        HGOTO_ERROR(H5E_FILE, H5E_CANTSET, FAIL, "set end of space allocation request failed")
+
+    /* Set up the user data for cache callbacks */
+    udata.f = f;
+    udata.ignore_drvrinfo = H5F_HAS_FEATURE(f, H5FD_FEAT_IGNORE_DRVRINFO);
+    udata.sym_leaf_k = 0;
+    if(H5P_get(c_plist, H5F_CRT_BTREE_RANK_NAME, udata.btree_k) < 0)
+        HGOTO_ERROR(H5E_FILE, H5E_CANTGET, FAIL, "unable to get rank for btree internal nodes")
+    udata.stored_eof = HADDR_UNDEF;
+    udata.drvrinfo_removed = FALSE;
 
     /* Look up the superblock */
-    if(NULL == (sblock = (H5F_super_t *)H5AC_protect(f, dxpl_id, H5AC_SUPERBLOCK, (haddr_t)0, &dirtied, rw)))
+    if(NULL == (sblock = (H5F_super_t *)H5AC_protect(f, dxpl_id, H5AC_SUPERBLOCK, (haddr_t)0, &udata, rw_flags)))
         HGOTO_ERROR(H5E_FILE, H5E_CANTPROTECT, FAIL, "unable to load superblock")
 
-    /* Mark the superblock dirty if it was modified during loading or VFD indicated to do so */
-    if((H5AC_WRITE == rw) && (dirtied || H5F_HAS_FEATURE(f, H5FD_FEAT_DIRTY_SBLK_LOAD)))
-        sblock_flags |= H5AC__DIRTIED_FLAG;
-
     /* Pin the superblock in the cache */
     if(H5AC_pin_protected_entry(sblock) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTPIN, FAIL, "unable to pin superblock")
 
+    /* Mark the superblock dirty if it was modified during loading */
+    if(((rw_flags & H5AC__READ_ONLY_FLAG) == 0) && udata.ignore_drvrinfo && udata.drvrinfo_removed) {
+        HDassert(sblock->super_vers < HDF5_SUPERBLOCK_VERSION_2);
+        sblock_flags |= H5AC__DIRTIED_FLAG;
+    } /* end if */
+
+    /* The superblock must be flushed last (and collectively in parallel) */
+    sblock_flags |= H5AC__FLUSH_LAST_FLAG;
+#ifdef H5_HAVE_PARALLEL
+    sblock_flags |= H5AC__FLUSH_COLLECTIVELY_FLAG;
+#endif /* H5_HAVE_PARALLEL */
+
+    /* Check if superblock address is different from base address and adjust
+     * base address and "end of address" address if so.
+     */
+    if(!H5F_addr_eq(super_addr, sblock->base_addr)) {
+        /* Check if the superblock moved earlier in the file */
+        if(H5F_addr_lt(super_addr, sblock->base_addr))
+            udata.stored_eof -= (sblock->base_addr - super_addr);
+        else
+            /* The superblock moved later in the file */
+            udata.stored_eof += (super_addr - sblock->base_addr);
+
+        /* Adjust base address for offsets of the HDF5 data in the file */
+        sblock->base_addr = super_addr;
+
+        /* Set the base address for the file in the VFD now */
+        if(H5F__set_base_addr(f, sblock->base_addr) < 0)
+            HGOTO_ERROR(H5E_FILE, H5E_CANTSET, FAIL, "failed to set base address for file driver")
+
+        /* Indicate that the superblock should be marked dirty */
+        if((rw_flags & H5AC__READ_ONLY_FLAG) == 0)
+            sblock_flags |= H5AC__DIRTIED_FLAG;
+    } /* end if */
+
+    /* Set information in the file's creation property list */
+    if(H5P_set(c_plist, H5F_CRT_SUPER_VERS_NAME, &sblock->super_vers) < 0)
+        HGOTO_ERROR(H5E_FILE, H5E_CANTSET, FAIL, "unable to set superblock version")
+    if(H5P_set(c_plist, H5F_CRT_ADDR_BYTE_NUM_NAME, &sblock->sizeof_addr) < 0)
+        HGOTO_ERROR(H5E_FILE, H5E_CANTSET, FAIL, "unable to set byte number in an address")
+    if(H5P_set(c_plist, H5F_CRT_OBJ_BYTE_NUM_NAME, &sblock->sizeof_size) < 0)
+        HGOTO_ERROR(H5E_FILE, H5E_CANTSET, FAIL, "unable to set byte number for object size")
+
+    /* Handle the B-tree 'K' values */
+    if(sblock->super_vers < HDF5_SUPERBLOCK_VERSION_2) {
+        /* Sanity check */
+        HDassert(udata.sym_leaf_k != 0);
+
+        /* Set the symbol table internal node 'K' value */
+        if(H5P_set(c_plist, H5F_CRT_SYM_LEAF_NAME, &udata.sym_leaf_k) < 0)
+            HGOTO_ERROR(H5E_FILE, H5E_CANTSET, FAIL, "unable to set rank for symbol table leaf nodes")
+        sblock->sym_leaf_k = udata.sym_leaf_k;
+
+        /* Set the B-tree internal node values, etc */
+        if(H5P_set(c_plist, H5F_CRT_BTREE_RANK_NAME, udata.btree_k) < 0)
+            HGOTO_ERROR(H5E_FILE, H5E_CANTSET, FAIL, "unable to set rank for btree internal nodes")
+        HDmemcpy(sblock->btree_k, udata.btree_k, sizeof(unsigned) * (size_t)H5B_NUM_BTREE_ID);
+    } /* end if */
+    else {
+        /* Get the (default) B-tree internal node values, etc */
+        /* (Note: these may be reset in a superblock extension) */
+        if(H5P_get(c_plist, H5F_CRT_BTREE_RANK_NAME, sblock->btree_k) < 0)
+            HGOTO_ERROR(H5E_FILE, H5E_CANTGET, FAIL, "unable to get rank for btree internal nodes")
+        if(H5P_get(c_plist, H5F_CRT_SYM_LEAF_NAME, &sblock->sym_leaf_k) < 0)
+            HGOTO_ERROR(H5E_FILE, H5E_CANTGET, FAIL, "unable to get rank for btree internal nodes")
+    } /* end else */
+
+    /*
+     * The user-defined data is the area of the file before the base
+     * address.
+     */
+    if(H5P_set(c_plist, H5F_CRT_USER_BLOCK_NAME, &sblock->base_addr) < 0)
+        HGOTO_ERROR(H5E_FILE, H5E_CANTSET, FAIL, "unable to set userblock size")
+
+    /*
+     * Make sure that the data is not truncated. One case where this is
+     * possible is if the first file of a family of files was opened
+     * individually.
+     */
+    if(HADDR_UNDEF == (eof = H5FD_get_eof(f->shared->lf, H5FD_MEM_DEFAULT)))
+        HGOTO_ERROR(H5E_FILE, H5E_CANTGET, FAIL, "unable to determine file size")
+
+    /* (Account for the stored EOA being absolute offset -QAK) */
+    if((eof + sblock->base_addr) < udata.stored_eof)
+        HGOTO_ERROR(H5E_FILE, H5E_TRUNCATED, FAIL, "truncated file: eof = %llu, sblock->base_addr = %llu, stored_eoa = %llu", (unsigned long long)eof, (unsigned long long)sblock->base_addr, (unsigned long long)udata.stored_eof)
+
+    /*
+     * Tell the file driver how much address space has already been
+     * allocated so that it knows how to allocate additional memory.
+     */
+
+    /* Decode the optional driver information block */
+    if(H5F_addr_defined(sblock->driver_addr)) {
+        H5O_drvinfo_t *drvinfo;         /* Driver info */
+        H5F_drvrinfo_cache_ud_t drvrinfo_udata;  /* User data for metadata callbacks */
+        unsigned drvinfo_flags = H5AC__NO_FLAGS_SET;    /* Flags used in driver info block unprotect call */
+
+        /* Sanity check - driver info block should only be defined for
+         *      superblock version < 2.
+         */
+        HDassert(sblock->super_vers < HDF5_SUPERBLOCK_VERSION_2);
+
+        /* Set up user data */
+        drvrinfo_udata.f           = f;
+        drvrinfo_udata.driver_addr = sblock->driver_addr;
+
+        /* extend EOA so we can read at least the fixed sized 
+         * portion of the driver info block 
+         */
+        if(H5FD_set_eoa(f->shared->lf, H5FD_MEM_SUPER, sblock->driver_addr + H5F_DRVINFOBLOCK_HDR_SIZE) < 0) /* will extend eoa later if required */ 
+            HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, FAIL, \
+                        "set end of space allocation request failed")
+
+        /* Look up the driver info block */
+        if(NULL == (drvinfo = (H5O_drvinfo_t *)H5AC_protect(f, dxpl_id, H5AC_DRVRINFO, sblock->driver_addr, &drvrinfo_udata, rw_flags)))
+            HGOTO_ERROR(H5E_FILE, H5E_CANTPROTECT, FAIL, "unable to load driver info block")
+
+        /* Loading the driver info block is enough to set up the right info */
+
+        /* Check if we need to rewrite the driver info block info */
+        if ( ( (rw_flags & H5AC__READ_ONLY_FLAG) == 0 ) &&
+             ( H5F_HAS_FEATURE(f, H5FD_FEAT_DIRTY_DRVRINFO_LOAD) ) ) {
+
+            drvinfo_flags |= H5AC__DIRTIED_FLAG;
+        } /* end if */
+
+        /* set the pin entry flag so that the driver information block 
+         * cache entry will be pinned in the cache.
+         */
+        drvinfo_flags |= H5AC__PIN_ENTRY_FLAG;
+
+        /* Release the driver info block */
+        if(H5AC_unprotect(f, dxpl_id, H5AC_DRVRINFO, sblock->driver_addr, drvinfo, drvinfo_flags) < 0)
+            HGOTO_ERROR(H5E_FILE, H5E_CANTUNPROTECT, FAIL, "unable to release driver info block")
+
+        /* save a pointer to the driver information cache entry */
+        f->shared->drvinfo = drvinfo;
+    } /* end if */
+
+    /* (Account for the stored EOA being absolute offset -NAF) */
+    if(H5F__set_eoa(f, H5FD_MEM_SUPER, udata.stored_eof - sblock->base_addr) < 0)
+        HGOTO_ERROR(H5E_FILE, H5E_CANTSET, FAIL, "unable to set end-of-address marker for file")
+
+    /* Decode the optional superblock extension info */
+    if(H5F_addr_defined(sblock->ext_addr)) {
+        H5O_loc_t ext_loc;      /* "Object location" for superblock extension */
+        H5O_btreek_t btreek;    /* v1 B-tree 'K' value message from superblock extension */
+        H5O_drvinfo_t drvinfo;  /* Driver info message from superblock extension */
+	size_t u; 		/* Local index variable */
+        htri_t status;          /* Status for message existing */
+
+        /* Sanity check - superblock extension should only be defined for
+         *      superblock version >= 2.
+         */
+        HDassert(sblock->super_vers >= HDF5_SUPERBLOCK_VERSION_2);
+
+        /* Check for superblock extension being located "outside" the stored
+         *      'eoa' value, which can occur with the split/multi VFD.
+         */
+        if(H5F_addr_gt(sblock->ext_addr, udata.stored_eof)) {
+            /* Set the 'eoa' for the object header memory type large enough
+             *  to give some room for a reasonably sized superblock extension.
+             *  (This is _rather_ a kludge -QAK)
+             */
+            if(H5F__set_eoa(f, H5FD_MEM_OHDR, (haddr_t)(sblock->ext_addr + 1024)) < 0)
+                HGOTO_ERROR(H5E_FILE, H5E_CANTSET, FAIL, "unable to set end-of-address marker for file")
+        } /* end if */
+
+        /* Open the superblock extension */
+	if(H5F_super_ext_open(f, sblock->ext_addr, &ext_loc) < 0)
+            HGOTO_ERROR(H5E_FILE, H5E_CANTOPENOBJ, FAIL, "unable to open file's superblock extension")
+
+        /* Check for the extension having a 'driver info' message */
+        if((status = H5O_msg_exists(&ext_loc, H5O_DRVINFO_ID, dxpl_id)) < 0)
+            HGOTO_ERROR(H5E_FILE, H5E_EXISTS, FAIL, "unable to read object header")
+        if(status) {
+            /* Check for ignoring the driver info for this file */
+            if(!udata.ignore_drvrinfo) {
+
+                /* Retrieve the 'driver info' structure */
+                if(NULL == H5O_msg_read(&ext_loc, H5O_DRVINFO_ID, &drvinfo, dxpl_id))
+                    HGOTO_ERROR(H5E_FILE, H5E_CANTGET, FAIL, "driver info message not present")
+
+                /* Validate and decode driver information */
+                if(H5FD_sb_load(f->shared->lf, drvinfo.name, drvinfo.buf) < 0)
+                    HGOTO_ERROR(H5E_FILE, H5E_CANTDECODE, FAIL, "unable to decode driver information")
+
+                /* Reset driver info message */
+                H5O_msg_reset(H5O_DRVINFO_ID, &drvinfo);
+            } /* end else */
+        } /* end if */
+
+        /* Read in the shared OH message information if there is any */
+        if(H5SM_get_info(&ext_loc, c_plist, dxpl_id) < 0)
+            HGOTO_ERROR(H5E_FILE, H5E_CANTGET, FAIL, "unable to read SOHM table information")
+
+        /* Check for the extension having a 'v1 B-tree "K"' message */
+        if((status = H5O_msg_exists(&ext_loc, H5O_BTREEK_ID, dxpl_id)) < 0)
+            HGOTO_ERROR(H5E_FILE, H5E_EXISTS, FAIL, "unable to read object header")
+        if(status) {
+            /* Retrieve the 'v1 B-tree "K"' structure */
+            if(NULL == H5O_msg_read(&ext_loc, H5O_BTREEK_ID, &btreek, dxpl_id))
+                HGOTO_ERROR(H5E_FILE, H5E_CANTGET, FAIL, "v1 B-tree 'K' info message not present")
+
+            /* Set non-default v1 B-tree 'K' value info from file */
+            sblock->btree_k[H5B_CHUNK_ID] = btreek.btree_k[H5B_CHUNK_ID];
+            sblock->btree_k[H5B_SNODE_ID] = btreek.btree_k[H5B_SNODE_ID];
+            sblock->sym_leaf_k = btreek.sym_leaf_k;
+
+            /* Set non-default v1 B-tree 'K' values in the property list */
+            if(H5P_set(c_plist, H5F_CRT_BTREE_RANK_NAME, btreek.btree_k) < 0)
+                HGOTO_ERROR(H5E_FILE, H5E_CANTSET, FAIL, "unable to set rank for btree internal nodes")
+            if(H5P_set(c_plist, H5F_CRT_SYM_LEAF_NAME, &btreek.sym_leaf_k) < 0)
+                HGOTO_ERROR(H5E_FILE, H5E_CANTSET, FAIL, "unable to set rank for symbol table leaf nodes")
+        } /* end if */
+
+        /* Check for the extension having a 'free-space manager info' message */
+        if((status = H5O_msg_exists(&ext_loc, H5O_FSINFO_ID, dxpl_id)) < 0)
+            HGOTO_ERROR(H5E_FILE, H5E_EXISTS, FAIL, "unable to read object header")
+        if(status) {
+            H5O_fsinfo_t fsinfo;    /* Free-space manager info message from superblock extension */
+
+            /* Retrieve the 'free-space manager info' structure */
+	    if(NULL == H5O_msg_read(&ext_loc, H5O_FSINFO_ID, &fsinfo, dxpl_id))
+                HGOTO_ERROR(H5E_FILE, H5E_CANTGET, FAIL, "unable to get free-space manager info message")
+
+            /* Check for non-default info */
+	    if(f->shared->fs_strategy != fsinfo.strategy) {
+		f->shared->fs_strategy = fsinfo.strategy;
+
+		/* Set non-default strategy in the property list */
+		if(H5P_set(c_plist, H5F_CRT_FILE_SPACE_STRATEGY_NAME, &fsinfo.strategy) < 0)
+		    HGOTO_ERROR(H5E_FILE, H5E_CANTSET, FAIL, "unable to set file space strategy")
+	    } /* end if */
+	    if(f->shared->fs_threshold != fsinfo.threshold) {
+		f->shared->fs_threshold = fsinfo.threshold;
+
+		/* Set non-default threshold in the property list */
+		if(H5P_set(c_plist, H5F_CRT_FREE_SPACE_THRESHOLD_NAME, &fsinfo.threshold) < 0)
+		    HGOTO_ERROR(H5E_FILE, H5E_CANTSET, FAIL, "unable to set file space strategy")
+	    } /* end if */
+
+	    /* Set free-space manager addresses */
+	    f->shared->fs_addr[0] = HADDR_UNDEF;
+	    for(u = 1; u < NELMTS(f->shared->fs_addr); u++)
+		f->shared->fs_addr[u] = fsinfo.fs_addr[u-1];
+        } /* end if */
+
+        /* Close superblock extension */
+        if(H5F_super_ext_close(f, &ext_loc, dxpl_id, FALSE) < 0)
+	    HGOTO_ERROR(H5E_FILE, H5E_CANTCLOSEOBJ, FAIL, "unable to close file's superblock extension")
+    } /* end if */
+
+    /* Update the driver info if VFD indicated to do so */
+    /* (NOTE: only for later versions of superblock, earlier versions are handled
+     *          earlier in this routine.
+     */
+    if(((rw_flags & H5AC__READ_ONLY_FLAG) == 0) &&
+            sblock->super_vers >= HDF5_SUPERBLOCK_VERSION_2 &&
+            H5F_addr_defined(sblock->ext_addr)) {
+        /* Check for modifying the driver info when opening the file */
+        if(H5F_HAS_FEATURE(f, H5FD_FEAT_DIRTY_DRVRINFO_LOAD)) {
+            size_t          driver_size;    /* Size of driver info block (bytes) */
+
+            /* Check for driver info message */
+            H5_CHECKED_ASSIGN(driver_size, size_t, H5FD_sb_size(f->shared->lf), hsize_t);
+            if(driver_size > 0) {
+                H5O_drvinfo_t drvinfo;      /* Driver info */
+                uint8_t dbuf[H5F_MAX_DRVINFOBLOCK_SIZE];  /* Driver info block encoding buffer */
+
+                /* Sanity check */
+                HDassert(driver_size <= H5F_MAX_DRVINFOBLOCK_SIZE);
+
+                /* Encode driver-specific data */
+                if(H5FD_sb_encode(f->shared->lf, drvinfo.name, dbuf) < 0)
+                    HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, FAIL, "unable to encode driver information")
+
+                /* Set the driver info information for the superblock extension */
+                drvinfo.len = driver_size;
+                drvinfo.buf = dbuf;
+
+                /* Write driver info information to the superblock extension */
+
+#if 1 /* bug fix test code -- tidy this up if all goes well */ /* JRM */
+		/* KLUGE ALERT!!
+		 *
+		 * H5F_super_ext_write_msg() expects f->shared->sblock to 
+		 * be set -- verify that it is NULL, and then set it.
+		 * Set it back to NULL when we are done.
+		 */
+		HDassert(f->shared->sblock == NULL);
+		f->shared->sblock = sblock;
+#endif /* JRM */
+
+                if(H5F_super_ext_write_msg(f, dxpl_id, &drvinfo, H5O_DRVINFO_ID, FALSE) < 0)
+                    HGOTO_ERROR(H5E_FILE, H5E_WRITEERROR, FAIL, "error in writing message to superblock extension")
+
+#if 1 /* bug fix test code -- tidy this up if all goes well */ /* JRM */
+		f->shared->sblock = NULL;
+#endif /* JRM */
+
+            } /* end if */
+        } /* end if */
+        /* Check for eliminating the driver info block */
+        else if(H5F_HAS_FEATURE(f, H5FD_FEAT_IGNORE_DRVRINFO)) {
+            /* Remove the driver info message from the superblock extension */
+            if(H5F_super_ext_remove_msg(f, dxpl_id, H5O_DRVINFO_ID) < 0)
+                HGOTO_ERROR(H5E_FILE, H5E_CANTRELEASE, FAIL, "error in removing message from superblock extension")
+
+            /* Check if the superblock extension was removed */
+            if(!H5F_addr_defined(sblock->ext_addr))
+                sblock_flags |= H5AC__DIRTIED_FLAG;
+        } /* end if */
+    } /* end if */
+
     /* Set the pointer to the pinned superblock */
     f->shared->sblock = sblock;
 
@@ -309,6 +651,32 @@ done:
     if(sblock && H5AC_unprotect(f, dxpl_id, H5AC_SUPERBLOCK, (haddr_t)0, sblock, sblock_flags) < 0)
         HDONE_ERROR(H5E_FILE, H5E_CANTUNPROTECT, FAIL, "unable to close superblock")
 
+    /* If we have failed, make sure no entries are left in the 
+     * metadata cache, so that it can be shut down and discarded.
+     */
+    if(ret_value < 0) { 
+        /* Unpin and discard drvinfo cache entry */
+        if(f->shared->drvinfo) {
+            if(H5AC_unpin_entry(f->shared->drvinfo) < 0)
+                HDONE_ERROR(H5E_FILE, H5E_CANTUNPIN, FAIL, "unable to unpin driver info")
+
+            /* Evict the driver info block from the cache */
+            if(H5AC_expunge_entry(f, dxpl_id, H5AC_DRVRINFO, sblock->driver_addr, H5AC__NO_FLAGS_SET) < 0)
+                HDONE_ERROR(H5E_FILE, H5E_CANTEXPUNGE, FAIL, "unable to expunge driver info block")
+        } /* end if */
+
+        /* Unpin & discard superblock */
+        if(sblock) {
+            /* Unpin superblock in cache */
+            if(H5AC_unpin_entry(sblock) < 0)
+                HDONE_ERROR(H5E_FILE, H5E_CANTUNPIN, FAIL, "unable to unpin superblock")
+
+            /* Evict the superblock from the cache */
+            if(H5AC_expunge_entry(f, dxpl_id, H5AC_SUPERBLOCK, (haddr_t)0, H5AC__NO_FLAGS_SET) < 0)
+                HDONE_ERROR(H5E_FILE, H5E_CANTEXPUNGE, FAIL, "unable to expunge superblock")
+        } /* end if */
+    } /* end if */
+
     FUNC_LEAVE_NOAPI_TAG(ret_value, FAIL)
 } /* end H5F__super_read() */
 
@@ -334,6 +702,8 @@ H5F__super_init(H5F_t *f, hid_t dxpl_id)
 {
     H5F_super_t    *sblock = NULL;      /* Superblock cache structure                 */
     hbool_t         sblock_in_cache = FALSE;    /* Whether the superblock has been inserted into the metadata cache */
+    H5O_drvinfo_t  *drvinfo = NULL;     /* Driver info */
+    hbool_t         drvinfo_in_cache = FALSE;   /* Whether the driver info block has been inserted into the metadata cache */
     H5P_genplist_t *plist;              /* File creation property list                */
     hsize_t         userblock_size;     /* Size of userblock, in bytes                */
     hsize_t         superblock_size;    /* Size of superblock, in bytes               */
@@ -427,11 +797,13 @@ H5F__super_init(H5F_t *f, hid_t dxpl_id)
     if(H5F__set_base_addr(f, sblock->base_addr) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, FAIL, "failed to set base address for file driver")
 
-    /* Save a local copy of the superblock version number */
+    /* Save a local copy of the superblock version number, size of addresses & offsets */
     sblock->super_vers = super_vers;
+    sblock->sizeof_addr = f->shared->sizeof_addr;
+    sblock->sizeof_size = f->shared->sizeof_size;
 
     /* Compute the size of the superblock */
-    superblock_size = (hsize_t)H5F_SUPERBLOCK_SIZE(super_vers, f);
+    superblock_size = (hsize_t)H5F_SUPERBLOCK_SIZE(sblock);
 
     /* Compute the size of the driver information block */
     H5_CHECKED_ASSIGN(driver_size, size_t, H5FD_sb_size(f->shared->lf), hsize_t);
@@ -446,10 +818,10 @@ H5F__super_init(H5F_t *f, hid_t dxpl_id)
     } /* end if */
 
     /*
-     * Allocate space for the userblock, superblock & driver info blocks.
-     * We do it with one allocation request because the userblock and
-     * superblock need to be at the beginning of the file and only the first
-     * allocation request is required to return memory at format address zero.
+     * Allocate space for the superblock & driver info block.
+     * We do it with one allocation request because the superblock needs to be
+     * at the beginning of the file and only the first allocation request is
+     * required to return memory at format address zero.
      */
     if(super_vers < HDF5_SUPERBLOCK_VERSION_2)
         superblock_size += driver_size;
@@ -466,6 +838,9 @@ H5F__super_init(H5F_t *f, hid_t dxpl_id)
     /* Keep a copy of the superblock info */
     f->shared->sblock = sblock;
 
+    /* set the drvinfo filed to NULL -- will overwrite this later if needed */
+    f->shared->drvinfo = NULL;
+
     /*
      * Determine if we will need a superblock extension
      */
@@ -572,6 +947,33 @@ H5F__super_init(H5F_t *f, hid_t dxpl_id)
                 HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, FAIL, "unable to update free-space info header message")
 	} /* end if */
     } /* end if */
+    else {
+        /* Check for creating an "old-style" driver info block */
+        if(driver_size > 0) {
+            /* Sanity check */
+            HDassert(H5F_addr_defined(sblock->driver_addr));
+
+            /* Allocate space for the driver info */
+            if(NULL == (drvinfo = (H5O_drvinfo_t *)H5MM_calloc(sizeof(H5O_drvinfo_t))))
+                HGOTO_ERROR(H5E_FILE, H5E_CANTALLOC, FAIL, "memory allocation failed for driver info message")
+
+            /* Set up driver info message */
+            /* (NOTE: All the actual information (name & driver information) is
+             *          actually based on the VFD info in the file handle and
+             *          will be encoded by the VFD's 'encode' callback, so it
+             *          doesn't need to be set here. -QAK, 7/20/2013
+             */
+            H5_CHECKED_ASSIGN(drvinfo->len, size_t, H5FD_sb_size(f->shared->lf), hsize_t);
+
+            /* Insert driver info block into cache */
+            if(H5AC_insert_entry(f, dxpl_id, H5AC_DRVRINFO, sblock->driver_addr, drvinfo, H5AC__PIN_ENTRY_FLAG | H5AC__FLUSH_LAST_FLAG | H5AC__FLUSH_COLLECTIVELY_FLAG) < 0)
+                HGOTO_ERROR(H5E_FILE, H5E_CANTINS, FAIL, "can't add driver info block to cache")
+            drvinfo_in_cache = TRUE;
+            f->shared->drvinfo = drvinfo;
+        } /* end if */
+        else
+            HDassert(!H5F_addr_defined(sblock->driver_addr));
+    } /* end if */
 
 done:
     /* Close superblock extension, if it was created */
@@ -580,6 +982,23 @@ done:
 
     /* Cleanup on failure */
     if(ret_value < 0) {
+        /* Check if the driver info block has been allocated yet */
+        if(drvinfo) {
+            /* Check if we've cached it already */
+            if(drvinfo_in_cache) {
+                /* Unpin drvinfo in cache */
+                if(H5AC_unpin_entry(drvinfo) < 0)
+                    HDONE_ERROR(H5E_FILE, H5E_CANTUNPIN, FAIL, "unable to unpin driver info")
+
+                /* Evict the driver info block from the cache */
+                if(H5AC_expunge_entry(f, dxpl_id, H5AC_DRVRINFO, sblock->driver_addr, H5AC__NO_FLAGS_SET) < 0)
+                    HDONE_ERROR(H5E_FILE, H5E_CANTEXPUNGE, FAIL, "unable to expunge driver info block")
+            } /* end if */
+            else
+                /* Free driver info block */
+                H5MM_xfree(drvinfo);
+        } /* end if */
+
         /* Check if the superblock has been allocated yet */
         if(sblock) {
             /* Check if we've cached it already */
@@ -635,6 +1054,14 @@ H5F_super_dirty(H5F_t *f)
     if(H5AC_mark_entry_dirty(f->shared->sblock) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTMARKDIRTY, FAIL, "unable to mark superblock as dirty")
 
+    /* if the driver information block exists, mark it dirty as well 
+     * so that the change in eoa will be reflected there as well if 
+     * appropriate.
+     */
+    if ( f->shared->drvinfo )
+        if(H5AC_mark_entry_dirty(f->shared->drvinfo) < 0)
+            HGOTO_ERROR(H5E_FILE, H5E_CANTMARKDIRTY, FAIL, "unable to mark drvinfo as dirty")
+
 done:
     FUNC_LEAVE_NOAPI(ret_value)
 } /* H5F_super_dirty() */
@@ -698,7 +1125,7 @@ H5F__super_size(H5F_t *f, hid_t dxpl_id, hsize_t *super_size, hsize_t *super_ext
 
     /* Set the superblock size */
     if(super_size)
-	*super_size = (hsize_t)H5F_SUPERBLOCK_SIZE(f->shared->sblock->super_vers, f);
+	*super_size = (hsize_t)H5F_SUPERBLOCK_SIZE(f->shared->sblock);
 
     /* Set the superblock extension size */
     if(super_ext_size) {
diff --git a/src/H5Fsuper_cache.c b/src/H5Fsuper_cache.c
index ded845d..ac1f840 100644
--- a/src/H5Fsuper_cache.c
+++ b/src/H5Fsuper_cache.c
@@ -51,9 +51,6 @@
 /* Local Macros */
 /****************/
 
-/* Maximum size of super-block buffers */
-#define H5F_MAX_SUPERBLOCK_SIZE  134
-
 
 /******************/
 /* Local Typedefs */
@@ -70,28 +67,70 @@
 /********************/
 
 /* Metadata cache (H5AC) callbacks */
-static H5F_super_t *H5F_sblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata);
-static herr_t H5F_sblock_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5F_super_t *sblock);
-static herr_t H5F_sblock_dest(H5F_t *f, H5F_super_t * sblock);
-static herr_t H5F_sblock_clear(H5F_t *f, H5F_super_t *sblock, hbool_t destroy);
-static herr_t H5F_sblock_size(const H5F_t *f, const H5F_super_t *sblock, size_t *size_ptr);
+static herr_t H5F__cache_superblock_get_load_size(const void *udata, size_t *image_len);
+static void *H5F__cache_superblock_deserialize(const void *image, size_t len,
+    void *udata, hbool_t *dirty);
+static herr_t H5F__cache_superblock_image_len(const void *thing, 
+    size_t *image_len, hbool_t *compressed_ptr, 
+    size_t *compressed_image_len_ptr);
+static herr_t H5F__cache_superblock_pre_serialize(const H5F_t *f, 
+    hid_t dxpl_id, void *thing, haddr_t addr, size_t len, 
+    size_t compressed_len, haddr_t *new_addr, size_t *new_len, 
+    size_t *new_compressed_len, unsigned *flags);
+static herr_t H5F__cache_superblock_serialize(const H5F_t *f, void *image, size_t len,
+    void *thing);
+static herr_t H5F__cache_superblock_free_icr(void *thing);
+
+static herr_t H5F__cache_drvrinfo_get_load_size(const void *udata, size_t *image_len);
+static void *H5F__cache_drvrinfo_deserialize(const void *image, size_t len,
+    void *udata, hbool_t *dirty);
+static herr_t H5F__cache_drvrinfo_image_len(const void *thing, 
+    size_t *image_len, hbool_t *compressed_ptr, 
+    size_t *compressed_image_len_ptr);
+static herr_t H5F__cache_drvrinfo_serialize(const H5F_t *f, void *image, size_t len,
+    void *thing);
+static herr_t H5F__cache_drvrinfo_free_icr(void *thing);
 
 
 /*********************/
 /* Package Variables */
 /*********************/
 
-/* H5F inherits cache-like properties from H5AC */
+/* H5F superblock inherits cache-like properties from H5AC */
 const H5AC_class_t H5AC_SUPERBLOCK[1] = {{
-    H5AC_SUPERBLOCK_ID,
-    (H5AC_load_func_t)H5F_sblock_load,
-    (H5AC_flush_func_t)H5F_sblock_flush,
-    (H5AC_dest_func_t)H5F_sblock_dest,
-    (H5AC_clear_func_t)H5F_sblock_clear,
-    (H5AC_notify_func_t)NULL,
-    (H5AC_size_func_t)H5F_sblock_size,
+    H5AC_SUPERBLOCK_ID,                 /* Metadata client ID */
+    "Superblock",                       /* Metadata client name (for debugging) */
+    H5FD_MEM_SUPER,                     /* File space memory type for client */
+    H5AC__CLASS_SPECULATIVE_LOAD_FLAG,  /* Client class behavior flags */
+    H5F__cache_superblock_get_load_size,/* 'get_load_size' callback */
+    H5F__cache_superblock_deserialize,  /* 'deserialize' callback */
+    H5F__cache_superblock_image_len,    /* 'image_len' callback */
+    H5F__cache_superblock_pre_serialize,/* 'pre_serialize' callback */
+    H5F__cache_superblock_serialize,    /* 'serialize' callback */
+    NULL,                               /* 'notify' callback */
+    H5F__cache_superblock_free_icr,     /* 'free_icr' callback */
+    NULL,				/* 'clear' callback */
+    NULL,                               /* 'fsf_size' callback */
+}};
+
+/* H5F driver info block inherits cache-like properties from H5AC */
+const H5AC_class_t H5AC_DRVRINFO[1] = {{
+    H5AC_DRVRINFO_ID,                   /* Metadata client ID */
+    "Driver info block",                /* Metadata client name (for debugging) */
+    H5FD_MEM_SUPER,                     /* File space memory type for client */
+    H5AC__CLASS_SPECULATIVE_LOAD_FLAG,  /* Client class behavior flags */
+    H5F__cache_drvrinfo_get_load_size,  /* 'get_load_size' callback */
+    H5F__cache_drvrinfo_deserialize,    /* 'deserialize' callback */
+    H5F__cache_drvrinfo_image_len,      /* 'image_len' callback */
+    NULL,                               /* 'pre_serialize' callback */
+    H5F__cache_drvrinfo_serialize,      /* 'serialize' callback */
+    NULL,                               /* 'notify' callback */
+    H5F__cache_drvrinfo_free_icr,       /* 'free_icr' callback */
+    NULL,				/* 'clear' callback */
+    NULL,                               /* 'fsf_size' callback */
 }};
 
+
 /*****************************/
 /* Library Private Variables */
 /*****************************/
@@ -107,546 +146,470 @@ H5FL_EXTERN(H5F_super_t);
 
 
 /*-------------------------------------------------------------------------
- * Function:    H5F_sblock_load
+ * Function:    H5F__cache_superblock_get_load_size
  *
- * Purpose:     Loads the superblock from the file, and deserializes
- *              its information into the H5F_super_t structure.
+ * Purpose:     Compute the size of the data structure on disk.
  *
- * Return:      Success:        SUCCEED
- *              Failure:        NULL
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:  Mike McGreevy
- *              mamcgree@hdfgroup.org
- *              April 8, 2009
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              July 17, 2013
  *
  *-------------------------------------------------------------------------
  */
-static H5F_super_t *
-H5F_sblock_load(H5F_t *f, hid_t dxpl_id, haddr_t H5_ATTR_UNUSED addr, void *_udata)
+static herr_t
+H5F__cache_superblock_get_load_size(const void H5_ATTR_UNUSED *udata, size_t *image_len)
 {
-    H5F_super_t        *sblock = NULL;      /* File's superblock */
-    haddr_t             base_addr = HADDR_UNDEF;        /* Base address of file */
-    uint8_t             sbuf[H5F_MAX_SUPERBLOCK_SIZE];     /* Buffer for superblock */
-    H5P_genplist_t     *dxpl;               /* DXPL object */
-    H5P_genplist_t     *c_plist;            /* File creation property list  */
-    H5F_file_t         *shared;             /* shared part of `file'        */
-    H5FD_t             *lf;                 /* file driver part of `shared' */
-    haddr_t             stored_eof;         /* stored end-of-file address in file  */
-    haddr_t             eof;                /* end of file address           */
-    uint8_t             sizeof_addr;        /* Size of offsets in the file (in bytes) */
-    uint8_t             sizeof_size;        /* Size of lengths in the file (in bytes) */
-    const size_t        fixed_size = H5F_SUPERBLOCK_FIXED_SIZE; /*fixed sizeof superblock   */
-    size_t              variable_size;      /*variable sizeof superblock    */
-    uint8_t            *p;                  /* Temporary pointer into encoding buffer */
-    unsigned            super_vers;         /* Superblock version          */
-    hbool_t            *dirtied = (hbool_t *)_udata;  /* Set up dirtied out value */
-    H5F_super_t        *ret_value;          /* Return value */
-
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC_NOERR
 
     /* Check arguments */
-    HDassert(f);
-    HDassert(H5F_addr_eq(addr, 0));
-    HDassert(dirtied);
+    HDassert(image_len);
 
-    /* Short cuts */
-    shared = f->shared;
-    lf = shared->lf;
+    /* Set the initial image length size */
+    *image_len = H5F_SUPERBLOCK_FIXED_SIZE +    /* Fixed size of superblock */
+        H5F_SUPERBLOCK_MINIMAL_VARLEN_SIZE;
 
-    /* Get the shared file creation property list */
-    if(NULL == (c_plist = (H5P_genplist_t *)H5I_object(shared->fcpl_id)))
-        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "can't get property list")
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5F__cache_superblock_get_load_size() */
 
-    /* Get the base address for the file in the VFD */
-    if(HADDR_UNDEF == (base_addr = H5FD_get_base_addr(lf)))
-        HGOTO_ERROR(H5E_FILE, H5E_CANTGET, NULL, "failed to get base address for file driver")
+
+/*-------------------------------------------------------------------------
+ * Function:	H5F__cache_superblock_deserialize
+ *
+ * Purpose:	Loads an object from the disk.
+ *
+ * Return:	Success:	Pointer to new object
+ *		Failure:	NULL
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@hdfgroup.org
+ *		July 18 2013
+ *
+ *-------------------------------------------------------------------------
+ */
+static void *
+H5F__cache_superblock_deserialize(const void *_image, size_t len, void *_udata,
+    hbool_t H5_ATTR_UNUSED *dirty)
+{
+    H5F_super_t         *sblock = NULL; /* File's superblock */
+    H5F_superblock_cache_ud_t *udata = (H5F_superblock_cache_ud_t *)_udata; /* User data */
+    const uint8_t	*image = (const uint8_t *)_image;       /* Pointer into raw data buffer */
+    size_t              variable_size;  /* Sariable size of superblock */
+    unsigned            super_vers;     /* Superblock version */
+    uint8_t             sizeof_addr;    /* Size of offsets in the file (in bytes) */
+    uint8_t             sizeof_size;    /* Size of lengths in the file (in bytes) */
+    H5F_super_t         *ret_value;     /* Return value */
+
+    FUNC_ENTER_STATIC
+
+    /* Check arguments */
+    HDassert(image);
+    HDassert(udata);
+    HDassert(udata->f);
 
     /* Allocate space for the superblock */
     if(NULL == (sblock = H5FL_CALLOC(H5F_super_t)))
         HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed")
 
-    /* The superblock must be flushed last (and collectively in parallel) */
-    sblock->cache_info.flush_me_last = TRUE;
-#ifdef H5_HAVE_PARALLEL
-    sblock->cache_info.flush_me_collectively = TRUE;
-#endif
-
-    /* Get the DXPL plist object for DXPL ID */
-    if(NULL == (dxpl = (H5P_genplist_t *)H5I_object(dxpl_id)))
-        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "can't get property list")
-
-    /* Read fixed-size portion of the superblock */
-    p = sbuf;
-    H5_CHECK_OVERFLOW(fixed_size, size_t, haddr_t);
-    if(H5FD_set_eoa(lf, H5FD_MEM_SUPER, (haddr_t)fixed_size) < 0)
-        HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, NULL, "set end of space allocation request failed")
-    if(H5FD_read(lf, dxpl, H5FD_MEM_SUPER, (haddr_t)0, fixed_size, p) < 0)
-        HGOTO_ERROR(H5E_FILE, H5E_READERROR, NULL, "unable to read superblock")
-
     /* Skip over signature (already checked when locating the superblock) */
-    p += H5F_SIGNATURE_LEN;
+    image += H5F_SIGNATURE_LEN;
 
     /* Superblock version */
-    super_vers = *p++;
+    super_vers = *image++;
     if(super_vers > HDF5_SUPERBLOCK_VERSION_LATEST)
         HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad superblock version number")
-    if(H5P_set(c_plist, H5F_CRT_SUPER_VERS_NAME, &super_vers) < 0)
-        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, NULL, "unable to set superblock version")
 
     /* Record the superblock version */
     sblock->super_vers = super_vers;
 
     /* Sanity check */
-    HDassert(((size_t)(p - sbuf)) == fixed_size);
+    HDassert(((size_t)(image - (const uint8_t *)_image)) == H5F_SUPERBLOCK_FIXED_SIZE);
+    HDassert(len >= H5F_SUPERBLOCK_FIXED_SIZE + 6);
+
+    /* Determine the size of addresses & size of offsets, for computing the
+     * variable-sized portion of the superblock.
+     */
+    if(super_vers < HDF5_SUPERBLOCK_VERSION_2) {
+        sizeof_addr = image[4];
+        sizeof_size = image[5];
+    } /* end if */
+    else {
+        sizeof_addr = image[0];
+        sizeof_size = image[1];
+    } /* end else */
+    if(sizeof_addr != 2 && sizeof_addr != 4 &&
+            sizeof_addr != 8 && sizeof_addr != 16 && sizeof_addr != 32)
+        HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad byte number in an address")
+    if(sizeof_size != 2 && sizeof_size != 4 &&
+            sizeof_size != 8 && sizeof_size != 16 && sizeof_size != 32)
+        HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad byte number for object size")
+    sblock->sizeof_addr = sizeof_addr;
+    sblock->sizeof_size = sizeof_size;
 
     /* Determine the size of the variable-length part of the superblock */
-    variable_size = (size_t)H5F_SUPERBLOCK_VARLEN_SIZE(super_vers, f);
+    variable_size = (size_t)H5F_SUPERBLOCK_VARLEN_SIZE(super_vers, sizeof_addr, sizeof_size);
     HDassert(variable_size > 0);
-    HDassert(fixed_size + variable_size <= sizeof(sbuf));
 
-    /* Read in variable-sized portion of superblock */
-    if(H5FD_set_eoa(lf, H5FD_MEM_SUPER, (haddr_t)(fixed_size + variable_size)) < 0)
-        HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, NULL, "set end of space allocation request failed")
-    if(H5FD_read(lf, dxpl, H5FD_MEM_SUPER, (haddr_t)fixed_size, variable_size, p) < 0)
-        HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "unable to read superblock")
+    /* Handle metadata cache retry for variable-sized portion of the superblock */
+    if(len != (H5F_SUPERBLOCK_FIXED_SIZE + variable_size)) {
+        /* Sanity check */
+        HDassert(len == (H5F_SUPERBLOCK_FIXED_SIZE + H5F_SUPERBLOCK_MINIMAL_VARLEN_SIZE));
 
-    /* Check for older version of superblock format */
-    if(super_vers < HDF5_SUPERBLOCK_VERSION_2) {
-        uint32_t	status_flags;	    /* File status flags	   */
-        unsigned        btree_k[H5B_NUM_BTREE_ID];  /* B-tree internal node 'K' values */
-        unsigned        sym_leaf_k;         /* Symbol table leaf node's 'K' value */
-
-        /* Freespace version (hard-wired) */
-        if(HDF5_FREESPACE_VERSION != *p++)
-            HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad free space version number")
-
-        /* Root group version number (hard-wired) */
-        if(HDF5_OBJECTDIR_VERSION != *p++)
-            HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad object directory version number")
-
-        /* Skip over reserved byte */
-        p++;
-
-        /* Shared header version number (hard-wired) */
-        if(HDF5_SHAREDHEADER_VERSION != *p++)
-            HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad shared-header format version number")
-
-        /* Size of file addresses */
-        sizeof_addr = *p++;
-        if(sizeof_addr != 2 && sizeof_addr != 4 &&
-                sizeof_addr != 8 && sizeof_addr != 16 && sizeof_addr != 32)
-            HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad byte number in an address")
-        if(H5P_set(c_plist, H5F_CRT_ADDR_BYTE_NUM_NAME, &sizeof_addr) < 0)
-            HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, NULL, "unable to set byte number in an address")
-        shared->sizeof_addr = sizeof_addr;  /* Keep a local copy also */
-
-        /* Size of file sizes */
-        sizeof_size = *p++;
-        if(sizeof_size != 2 && sizeof_size != 4 &&
-                sizeof_size != 8 && sizeof_size != 16 && sizeof_size != 32)
-            HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad byte number for object size")
-        if(H5P_set(c_plist, H5F_CRT_OBJ_BYTE_NUM_NAME, &sizeof_size) < 0)
-            HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, NULL, "unable to set byte number for object size")
-        shared->sizeof_size = sizeof_size;  /* Keep a local copy also */
-
-        /* Skip over reserved byte */
-        p++;
-
-        /* Various B-tree sizes */
-        UINT16DECODE(p, sym_leaf_k);
-        if(sym_leaf_k == 0)
-            HGOTO_ERROR(H5E_FILE, H5E_BADRANGE, NULL, "bad symbol table leaf node 1/2 rank")
-        if(H5P_set(c_plist, H5F_CRT_SYM_LEAF_NAME, &sym_leaf_k) < 0)
-            HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, NULL, "unable to set rank for symbol table leaf nodes")
-        sblock->sym_leaf_k = sym_leaf_k;    /* Keep a local copy also */
-
-        /* Need 'get' call to set other array values */
-        if(H5P_get(c_plist, H5F_CRT_BTREE_RANK_NAME, btree_k) < 0)
-            HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, NULL, "unable to get rank for btree internal nodes")
-        UINT16DECODE(p, btree_k[H5B_SNODE_ID]);
-        if(btree_k[H5B_SNODE_ID] == 0)
-            HGOTO_ERROR(H5E_FILE, H5E_BADRANGE, NULL, "bad 1/2 rank for btree internal nodes")
-        /*
-         * Delay setting the value in the property list until we've checked
-         * for the indexed storage B-tree internal 'K' value later.
-         */
-
-        /* File status flags (not really used yet) */
-        UINT32DECODE(p, status_flags);
-        HDassert(status_flags <= 255);
-        sblock->status_flags = (uint8_t)status_flags;
-        if(sblock->status_flags & ~H5F_SUPER_ALL_FLAGS)
-            HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad flag value for superblock")
-
-        /*
-         * If the superblock version # is greater than 0, read in the indexed
-         * storage B-tree internal 'K' value
-         */
-        if(super_vers > HDF5_SUPERBLOCK_VERSION_DEF) {
-            UINT16DECODE(p, btree_k[H5B_CHUNK_ID]);
-            /* Reserved bytes are present only in version 1 */
-            if(super_vers == HDF5_SUPERBLOCK_VERSION_1)
-                p += 2;   /* reserved */
-        } /* end if */
-        else
-            btree_k[H5B_CHUNK_ID] = HDF5_BTREE_CHUNK_IK_DEF;
+        /* Make certain we can read the variabled-sized portion of the superblock */
+        if(H5F__set_eoa(udata->f, H5FD_MEM_SUPER, (haddr_t)(H5F_SUPERBLOCK_FIXED_SIZE + variable_size)) < 0)
+            HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, NULL, "set end of space allocation request failed")
+    } /* end if */
+    else {
+        /* Check for older version of superblock format */
+        if(super_vers < HDF5_SUPERBLOCK_VERSION_2) {
+            uint32_t    status_flags;	    /* File status flags	   */
+            unsigned    sym_leaf_k;         /* Symbol table leaf node's 'K' value */
+            unsigned    snode_btree_k;      /* B-tree symbol table internal node 'K' value */
+            unsigned    chunk_btree_k;      /* B-tree chunk internal node 'K' value */
+
+            /* Freespace version (hard-wired) */
+            if(HDF5_FREESPACE_VERSION != *image++)
+                HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad free space version number")
+
+            /* Root group version number (hard-wired) */
+            if(HDF5_OBJECTDIR_VERSION != *image++)
+                HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad object directory version number")
+
+            /* Skip over reserved byte */
+            image++;
+
+            /* Shared header version number (hard-wired) */
+            if(HDF5_SHAREDHEADER_VERSION != *image++)
+                HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad shared-header format version number")
+
+            /* Size of file addresses */
+            sizeof_addr = *image++;
+            if(sizeof_addr != 2 && sizeof_addr != 4 &&
+                    sizeof_addr != 8 && sizeof_addr != 16 && sizeof_addr != 32)
+                HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad byte number in an address")
+            sblock->sizeof_addr = sizeof_addr;
+            udata->f->shared->sizeof_addr = sizeof_addr;  /* Keep a local copy also */
+
+            /* Size of file sizes */
+            sizeof_size = *image++;
+            if(sizeof_size != 2 && sizeof_size != 4 &&
+                    sizeof_size != 8 && sizeof_size != 16 && sizeof_size != 32)
+                HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad byte number for object size")
+            sblock->sizeof_size = sizeof_size;
+            udata->f->shared->sizeof_size = sizeof_size;  /* Keep a local copy also */
+
+            /* Skip over reserved byte */
+            image++;
+
+            /* Various B-tree sizes */
+            UINT16DECODE(image, sym_leaf_k);
+            if(sym_leaf_k == 0)
+                HGOTO_ERROR(H5E_FILE, H5E_BADRANGE, NULL, "bad symbol table leaf node 1/2 rank")
+            udata->sym_leaf_k = sym_leaf_k;    /* Keep a local copy also */
+
+            /* Need 'get' call to set other array values */
+            UINT16DECODE(image, snode_btree_k);
+            if(snode_btree_k == 0)
+                HGOTO_ERROR(H5E_FILE, H5E_BADRANGE, NULL, "bad 1/2 rank for btree internal nodes")
+            udata->btree_k[H5B_SNODE_ID] = snode_btree_k;
 
-        /* Set the B-tree internal node values, etc */
-        if(H5P_set(c_plist, H5F_CRT_BTREE_RANK_NAME, btree_k) < 0)
-            HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, NULL, "unable to set rank for btree internal nodes")
-        HDmemcpy(sblock->btree_k, btree_k, sizeof(unsigned) * (size_t)H5B_NUM_BTREE_ID);    /* Keep a local copy also */
+            /*
+             * Delay setting the value in the property list until we've checked
+             * for the indexed storage B-tree internal 'K' value later.
+             */
 
-        /* Remainder of "variable-sized" portion of superblock */
-        H5F_addr_decode(f, (const uint8_t **)&p, &sblock->base_addr/*out*/);
-        H5F_addr_decode(f, (const uint8_t **)&p, &sblock->ext_addr/*out*/);
-        H5F_addr_decode(f, (const uint8_t **)&p, &stored_eof/*out*/);
-        H5F_addr_decode(f, (const uint8_t **)&p, &sblock->driver_addr/*out*/);
+            /* File status flags (not really used yet) */
+            UINT32DECODE(image, status_flags);
+            HDassert(status_flags <= 255);
+            sblock->status_flags = (uint8_t)status_flags;
+            if(sblock->status_flags & ~H5F_SUPER_ALL_FLAGS)
+                HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad flag value for superblock")
 
-        /* Allocate space for the root group symbol table entry */
-        HDassert(!sblock->root_ent);
-        if(NULL == (sblock->root_ent = (H5G_entry_t *)H5MM_calloc(sizeof(H5G_entry_t))))
-            HGOTO_ERROR(H5E_FILE, H5E_CANTALLOC, NULL, "can't allocate space for root group symbol table entry")
+            /*
+             * If the superblock version # is greater than 0, read in the indexed
+             * storage B-tree internal 'K' value
+             */
+            if(super_vers > HDF5_SUPERBLOCK_VERSION_DEF) {
+                UINT16DECODE(image, chunk_btree_k);
 
-        /* decode the root group symbol table entry */
-        if(H5G_ent_decode(f, (const uint8_t **)&p, sblock->root_ent) < 0)
-            HGOTO_ERROR(H5E_FILE, H5E_CANTDECODE, NULL, "can't decode root group symbol table entry")
+                /* Reserved bytes are present only in version 1 */
+                if(super_vers == HDF5_SUPERBLOCK_VERSION_1)
+                    image += 2;   /* reserved */
+            } /* end if */
+            else
+                chunk_btree_k = HDF5_BTREE_CHUNK_IK_DEF;
+            udata->btree_k[H5B_CHUNK_ID] = chunk_btree_k;
+
+            /* Remainder of "variable-sized" portion of superblock */
+            H5F_addr_decode(udata->f, (const uint8_t **)&image, &sblock->base_addr/*out*/);
+            H5F_addr_decode(udata->f, (const uint8_t **)&image, &sblock->ext_addr/*out*/);
+            H5F_addr_decode(udata->f, (const uint8_t **)&image, &udata->stored_eof/*out*/);
+            H5F_addr_decode(udata->f, (const uint8_t **)&image, &sblock->driver_addr/*out*/);
+
+            /* Allocate space for the root group symbol table entry */
+            HDassert(!sblock->root_ent);
+            if(NULL == (sblock->root_ent = (H5G_entry_t *)H5MM_calloc(sizeof(H5G_entry_t))))
+                HGOTO_ERROR(H5E_FILE, H5E_CANTALLOC, NULL, "can't allocate space for root group symbol table entry")
+
+            /* decode the root group symbol table entry */
+            if(H5G_ent_decode(udata->f, (const uint8_t **)&image, sblock->root_ent) < 0)
+                HGOTO_ERROR(H5E_FILE, H5E_CANTDECODE, NULL, "can't decode root group symbol table entry")
+
+            /* Set the root group address to the correct value */
+            sblock->root_addr = sblock->root_ent->header;
+
+            /* This step is for h5repart tool only. If user wants to change file driver
+             *  from family to sec2 while using h5repart, set the driver address to
+             *  undefined to let the library ignore the family driver information saved
+             *  in the superblock.
+             */
+            if(udata->ignore_drvrinfo && H5F_addr_defined(sblock->driver_addr)) {
+                /* Eliminate the driver info */
+                sblock->driver_addr = HADDR_UNDEF;
+                udata->drvrinfo_removed = TRUE;
+            } /* end if */
 
-        /* Set the root group address to the correct value */
-        sblock->root_addr = sblock->root_ent->header;
+            /* NOTE: Driver info block is decoded separately, later */
 
-        /*
-         * Check if superblock address is different from base address and
-         * adjust base address and "end of address" address if so.
-         */
-        if(!H5F_addr_eq(base_addr, sblock->base_addr)) {
-            /* Check if the superblock moved earlier in the file */
-            if(H5F_addr_lt(base_addr, sblock->base_addr))
-                stored_eof -= (sblock->base_addr - base_addr);
-            else
-                /* The superblock moved later in the file */
-                stored_eof += (base_addr - sblock->base_addr);
+        } /* end if */
+        else {
+            uint32_t computed_chksum;       /* Computed checksum  */
+            uint32_t read_chksum;           /* Checksum read from file  */
+
+            /* Size of file addresses */
+            sizeof_addr = *image++;
+            if(sizeof_addr != 2 && sizeof_addr != 4 &&
+                    sizeof_addr != 8 && sizeof_addr != 16 && sizeof_addr != 32)
+                HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad byte number in an address")
+            sblock->sizeof_addr = sizeof_addr;
+            udata->f->shared->sizeof_addr = sizeof_addr;  /* Keep a local copy also */
+
+            /* Size of file sizes */
+            sizeof_size = *image++;
+            if(sizeof_size != 2 && sizeof_size != 4 &&
+                    sizeof_size != 8 && sizeof_size != 16 && sizeof_size != 32)
+                HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad byte number for object size")
+            sblock->sizeof_size = sizeof_size;
+            udata->f->shared->sizeof_size = sizeof_size;  /* Keep a local copy also */
+
+            /* File status flags (not really used yet) */
+            sblock->status_flags = *image++;
+            if(sblock->status_flags & ~H5F_SUPER_ALL_FLAGS)
+                HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad flag value for superblock")
+
+            /* Base, superblock extension, end of file & root group object header addresses */
+            H5F_addr_decode(udata->f, (const uint8_t **)&image, &sblock->base_addr/*out*/);
+            H5F_addr_decode(udata->f, (const uint8_t **)&image, &sblock->ext_addr/*out*/);
+            H5F_addr_decode(udata->f, (const uint8_t **)&image, &udata->stored_eof/*out*/);
+            H5F_addr_decode(udata->f, (const uint8_t **)&image, &sblock->root_addr/*out*/);
+
+            /* Compute checksum for superblock */
+            computed_chksum = H5_checksum_metadata(_image, (size_t)(image - (const uint8_t *)_image), 0);
+
+            /* Decode checksum */
+            UINT32DECODE(image, read_chksum);
+
+            /* Verify correct checksum */
+            if(read_chksum != computed_chksum)
+                HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "bad checksum on driver information block")
+
+            /* The Driver Information Block may not appear with the version
+             * 2 super block.  Thus we set the driver_addr field of the in 
+             * core representation of the super block HADDR_UNDEF to prevent 
+             * any attempt to load the Driver Information Block.
+             */
+            sblock->driver_addr = HADDR_UNDEF;
+        } /* end else */
+    } /* end else */
 
-            /* Adjust base address for offsets of the HDF5 data in the file */
-            sblock->base_addr = base_addr;
+    /* Sanity check */
+    HDassert((size_t)(image - (const uint8_t *)_image) <= len);
 
-            /* Set the base address for the file in the VFD now */
-            if(H5FD_set_base_addr(lf, sblock->base_addr) < 0)
-                HGOTO_ERROR(H5E_FILE, H5E_CANTSET, NULL, "failed to set base address for file driver")
+    /* Set return value */
+    ret_value = sblock;
 
-            /* Indicate that the superblock should be marked dirty */
-            *dirtied = TRUE;
-        } /* end if */
+done:
+    /* Release the [possibly partially initialized] superblock on error */
+    if(!ret_value && sblock)
+        if(H5F__super_free(sblock) < 0)
+            HDONE_ERROR(H5E_FILE, H5E_CANTFREE, NULL, "unable to destroy superblock data")
 
-        /* This step is for h5repart tool only. If user wants to change file driver
-         *  from family to sec2 while using h5repart, set the driver address to
-         *  undefined to let the library ignore the family driver information saved
-         *  in the superblock.
-         */
-        if(H5F_HAS_FEATURE(f, H5FD_FEAT_IGNORE_DRVRINFO)) {
-            /* Eliminate the driver info */
-            sblock->driver_addr = HADDR_UNDEF;
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5F__cache_superblock_deserialize() */
 
-            /* Indicate that the superblock should be marked dirty */
-            *dirtied = TRUE;
-        } /* end if */
+
+/*-------------------------------------------------------------------------
+ * Function:    H5F__cache_superblock_image_len
+ *
+ * Purpose:     Compute the size of the data structure on disk.
+ *
+ * Return:      Non-negative on success/Negative on failure
+ *
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              July 19, 2013
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5F__cache_superblock_image_len(const void *_thing, size_t *image_len, hbool_t *compressed_ptr, size_t H5_ATTR_UNUSED *compressed_image_len_ptr)
+{
+    const H5F_super_t *sblock = (const H5F_super_t *)_thing;    /* Pointer to the object */
 
-        /* Decode the optional driver information block */
-        if(H5F_addr_defined(sblock->driver_addr)) {
-            uint8_t dbuf[H5F_MAX_DRVINFOBLOCK_SIZE];     /* Buffer for driver info block */
-            char drv_name[9];       /* Name of driver */
-            unsigned drv_vers;      /* Version of driver info block */
-            size_t drv_variable_size; /* Size of variable-length portion of driver info block, in bytes */
-
-            /* Read in fixed-sized portion of driver info block */
-            p = dbuf;
-            if(H5FD_set_eoa(lf, H5FD_MEM_SUPER, sblock->driver_addr + H5F_DRVINFOBLOCK_HDR_SIZE) < 0)
-                HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, NULL, "set end of space allocation request failed")
-            if(H5FD_read(lf, dxpl, H5FD_MEM_SUPER, sblock->driver_addr, (size_t)H5F_DRVINFOBLOCK_HDR_SIZE, p) < 0)
-                HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "unable to read driver information block")
-
-            /* Version number */
-            drv_vers = *p++;
-            if(drv_vers != HDF5_DRIVERINFO_VERSION_0)
-                HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "bad driver information block version number")
-
-            p += 3; /* reserved bytes */
-
-            /* Driver info size */
-            UINT32DECODE(p, drv_variable_size);
-
-            /* Sanity check */
-            HDassert(H5F_DRVINFOBLOCK_HDR_SIZE + drv_variable_size <= sizeof(dbuf));
-
-            /* Driver name and/or version */
-            HDstrncpy(drv_name, (const char *)p, (size_t)8);
-            drv_name[8] = '\0';
-            p += 8; /* advance past name/version */
-
-            /* Read in variable-sized portion of driver info block */
-            if(H5FD_set_eoa(lf, H5FD_MEM_SUPER, sblock->driver_addr + H5F_DRVINFOBLOCK_HDR_SIZE + drv_variable_size) < 0)
-                HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, NULL, "set end of space allocation request failed")
-            if(H5FD_read(lf, dxpl, H5FD_MEM_SUPER, sblock->driver_addr + H5F_DRVINFOBLOCK_HDR_SIZE, drv_variable_size, p) < 0)
-                HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "unable to read file driver information")
-
-            /* Decode driver information */
-            if(H5FD_sb_load(lf, drv_name, p) < 0)
-                HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "unable to decode driver information")
-        } /* end if */
-    } /* end if */
-    else {
-        uint32_t computed_chksum;       /* Computed checksum  */
-        uint32_t read_chksum;           /* Checksum read from file  */
-
-        /* Size of file addresses */
-        sizeof_addr = *p++;
-        if(sizeof_addr != 2 && sizeof_addr != 4 &&
-                sizeof_addr != 8 && sizeof_addr != 16 && sizeof_addr != 32)
-            HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad byte number in an address")
-        if(H5P_set(c_plist, H5F_CRT_ADDR_BYTE_NUM_NAME, &sizeof_addr) < 0)
-            HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, NULL, "unable to set byte number in an address")
-        shared->sizeof_addr = sizeof_addr;  /* Keep a local copy also */
-
-        /* Size of file sizes */
-        sizeof_size = *p++;
-        if(sizeof_size != 2 && sizeof_size != 4 &&
-                sizeof_size != 8 && sizeof_size != 16 && sizeof_size != 32)
-            HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad byte number for object size")
-        if(H5P_set(c_plist, H5F_CRT_OBJ_BYTE_NUM_NAME, &sizeof_size) < 0)
-            HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, NULL, "unable to set byte number for object size")
-        shared->sizeof_size = sizeof_size;  /* Keep a local copy also */
-
-        /* File status flags (not really used yet) */
-        sblock->status_flags = *p++;
-        if(sblock->status_flags & ~H5F_SUPER_ALL_FLAGS)
-            HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad flag value for superblock")
-
-        /* Base, superblock extension, end of file & root group object header addresses */
-        H5F_addr_decode(f, (const uint8_t **)&p, &sblock->base_addr/*out*/);
-        H5F_addr_decode(f, (const uint8_t **)&p, &sblock->ext_addr/*out*/);
-        H5F_addr_decode(f, (const uint8_t **)&p, &stored_eof/*out*/);
-        H5F_addr_decode(f, (const uint8_t **)&p, &sblock->root_addr/*out*/);
-
-        /* Compute checksum for superblock */
-        computed_chksum = H5_checksum_metadata(sbuf, (size_t)(p - sbuf), 0);
-
-        /* Decode checksum */
-        UINT32DECODE(p, read_chksum);
-
-        /* Verify correct checksum */
-        if(read_chksum != computed_chksum)
-            HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "bad checksum on driver information block")
+    FUNC_ENTER_STATIC_NOERR
 
-        /*
-         * Check if superblock address is different from base address and
-         * adjust base address and "end of address" address if so.
-         */
-        if(!H5F_addr_eq(base_addr, sblock->base_addr)) {
-            /* Check if the superblock moved earlier in the file */
-            if(H5F_addr_lt(base_addr, sblock->base_addr))
-                stored_eof -= (sblock->base_addr - base_addr);
-            else
-                /* The superblock moved later in the file */
-                stored_eof += (base_addr - sblock->base_addr);
+    /* Check arguments */
+    HDassert(sblock);
+    HDassert(sblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(sblock->cache_info.type == H5AC_SUPERBLOCK);
+    HDassert(image_len);
+    HDassert(compressed_ptr);
 
-            /* Adjust base address for offsets of the HDF5 data in the file */
-            sblock->base_addr = base_addr;
+    /* Set the image length size */
+    *image_len = (size_t)H5F_SUPERBLOCK_SIZE(sblock);
 
-            /* Set the base address for the file in the VFD now */
-            if(H5FD_set_base_addr(lf, sblock->base_addr) < 0)
-                HGOTO_ERROR(H5E_FILE, H5E_CANTSET, NULL, "failed to set base address for file driver")
+    /* Set *compressed_ptr to FALSE unconditionally */
+    *compressed_ptr = FALSE;
 
-            /* Indicate that the superblock should be marked dirty */
-            *dirtied = TRUE;
-        } /* end if */
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5F__cache_superblock_image_len() */
 
-        /* Get the B-tree internal node values, etc */
-        if(H5P_get(c_plist, H5F_CRT_BTREE_RANK_NAME, sblock->btree_k) < 0)
-            HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, NULL, "unable to get rank for btree internal nodes")
-        if(H5P_get(c_plist, H5F_CRT_SYM_LEAF_NAME, &sblock->sym_leaf_k) < 0)
-            HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, NULL, "unable to get rank for btree internal nodes")
-    } /* end else */
+
+/*-------------------------------------------------------------------------
+ * Function:    H5FS__cache_hdf_pre_serialize
+ *
+ * Purpose:	The current use of this function is a cludge to repair an 
+ *		oversight in the conversion of the superblock code to use the 
+ *		version 3 cache.  
+ *
+ *		In the V2 metadata cache callbacks, the superblock dirver info 
+ *     		message was updated in the flush routine.  Note that this 
+ *		operation only applies to version 2 or later superblocks.
+ *
+ *     		Somehow, this functionality was lost in the conversion to use 
+ *     		the V3 cache, causing failures with the multi file driver 
+ *     		(and possibly the family file driver as well).
+ *
+ *     		Performing this operation is impossible in the current 
+ *		serialize routine, as the dxpl_id is not available.  While 
+ *		I am pretty sure that this is not the correct place for this 
+ *		functionality, as I can see it causing problems with both 
+ *		journaling and possibly parallel HDF5 as well, I am placing 
+ *		code for the necessary update in the pre_serialize call for 
+ *		now for testing purposes.  We will almost certainly want to 
+ *		change this.
+ *
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
+ *
+ * Programmer:  John Mainzer
+ *              10/82/14
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5F__cache_superblock_pre_serialize(const H5F_t *f, hid_t dxpl_id, 
+    void *_thing, haddr_t H5_ATTR_UNUSED addr, size_t H5_ATTR_UNUSED len, 
+    size_t H5_ATTR_UNUSED compressed_len, haddr_t H5_ATTR_UNUSED *new_addr, 
+    size_t H5_ATTR_UNUSED *new_len, size_t H5_ATTR_UNUSED *new_compressed_len, 
+    unsigned H5_ATTR_UNUSED *flags)
+{
+    H5F_super_t *sblock = (H5F_super_t *)_thing; /* Pointer to the super block */
+    herr_t ret_value = SUCCEED; /* Return value */
 
-    /*
-     * The user-defined data is the area of the file before the base
-     * address.
-     */
-    if(H5P_set(c_plist, H5F_CRT_USER_BLOCK_NAME, &sblock->base_addr) < 0)
-        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, NULL, "unable to set userblock size")
+    FUNC_ENTER_NOAPI_NOINIT
 
-    /*
-     * Make sure that the data is not truncated. One case where this is
-     * possible is if the first file of a family of files was opened
-     * individually.
-     */
-    if(HADDR_UNDEF == (eof = H5FD_get_eof(lf, H5FD_MEM_DEFAULT)))
-        HGOTO_ERROR(H5E_FILE, H5E_CANTGET, NULL, "unable to determine file size")
-
-    /* (Account for the stored EOF being absolute offset -QAK) */
-    if((eof + sblock->base_addr) < stored_eof)
-        HGOTO_ERROR(H5E_FILE, H5E_TRUNCATED, NULL,
-                    "truncated file: eof = %llu, sblock->base_addr = %llu, stored_eof = %llu",
-                    (unsigned long long)eof, (unsigned long long)sblock->base_addr, (unsigned long long)stored_eof)
-
-    /*
-     * Tell the file driver how much address space has already been
-     * allocated so that it knows how to allocate additional memory.
-     */
-    /* (Account for the stored EOA being absolute offset -NAF) */
-    if(H5FD_set_eoa(lf, H5FD_MEM_SUPER, stored_eof - sblock->base_addr) < 0)
-        HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "unable to set end-of-address marker for file")
-
-    /* Read the file's superblock extension, if there is one. */
-    if(H5F_addr_defined(sblock->ext_addr)) {
-        H5O_loc_t ext_loc;      /* "Object location" for superblock extension */
-        H5O_btreek_t btreek;    /* v1 B-tree 'K' value message from superblock extension */
-        H5O_drvinfo_t drvinfo;  /* Driver info message from superblock extension */
-	size_t u; 		/* Local index variable */
-        htri_t status;          /* Status for message existing */
-
-        /* Sanity check - superblock extension should only be defined for
-         *      superblock version >= 2.
+    /* Sanity check */
+    HDassert(f);
+    HDassert(sblock);
+    HDassert(sblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(sblock->cache_info.type == H5AC_SUPERBLOCK);
+    HDassert(flags);
+
+    if(sblock->super_vers >= HDF5_SUPERBLOCK_VERSION_2) {
+        /* WARNING: This code almost certainly doesn't belong here.  Must
+         *          discuss with Quincey where to put it.  Note issues
+         *          for journaling and possibly parallel.
+         *
+         *                                            -- JRM
          */
-        HDassert(super_vers >= HDF5_SUPERBLOCK_VERSION_2);
-
-        /* Check for superblock extension being located "outside" the stored
-         *      'eoa' value, which can occur with the split/multi VFD.
+        /* Update the driver information message in the superblock extension
+         * if appropriate.
          */
-        if(H5F_addr_gt(sblock->ext_addr, stored_eof)) {
-            /* Set the 'eoa' for the object header memory type large enough
-             *  to give some room for a reasonably sized superblock extension.
-             *  (This is _rather_ a kludge -QAK)
-             */
-            if(H5FD_set_eoa(lf, H5FD_MEM_OHDR, (haddr_t)(sblock->ext_addr + 1024)) < 0)
-                HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "unable to set end-of-address marker for file")
-        } /* end if */
+        if(H5F_addr_defined(sblock->ext_addr)) {
+            size_t     driver_size;    /* Size of driver info block (bytes)*/
+            H5O_loc_t  ext_loc;        /* "Object location" for superblock extension */
 
-        /* Open the superblock extension */
-	if(H5F_super_ext_open(f, sblock->ext_addr, &ext_loc) < 0)
-            HGOTO_ERROR(H5E_FILE, H5E_CANTOPENOBJ, NULL, "unable to open file's superblock extension")
+            HDassert(sblock->super_vers >= HDF5_SUPERBLOCK_VERSION_2);
+
+            /* Open the superblock extension's object header */
+            if(H5F_super_ext_open((H5F_t *)f, sblock->ext_addr, &ext_loc) < 0)
+                HGOTO_ERROR(H5E_FILE, H5E_CANTOPENOBJ, FAIL, "unable to open file's superblock extension")
 
-        /* Check for the extension having a 'driver info' message */
-        if((status = H5O_msg_exists(&ext_loc, H5O_DRVINFO_ID, dxpl_id)) < 0)
-            HGOTO_ERROR(H5E_FILE, H5E_CANTGET, NULL, "unable to read object header")
-        if(status) {
             /* Check for ignoring the driver info for this file */
-            if(H5F_HAS_FEATURE(f, H5FD_FEAT_IGNORE_DRVRINFO)) {
-                /* Indicate that the superblock should be marked dirty */
-                *dirtied = TRUE;
-            } /* end if */
-            else {
-                /* Retrieve the 'driver info' structure */
-                if(NULL == H5O_msg_read(&ext_loc, H5O_DRVINFO_ID, &drvinfo, dxpl_id))
-                    HGOTO_ERROR(H5E_FILE, H5E_CANTGET, NULL, "driver info message not present")
-
-                /* Decode driver information */
-                if(H5FD_sb_load(lf, drvinfo.name, drvinfo.buf) < 0)
-                    HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "unable to decode driver information")
-
-                /* Reset driver info message */
-                H5O_msg_reset(H5O_DRVINFO_ID, &drvinfo);
-            } /* end else */
-        } /* end if */
+            if(!H5F_HAS_FEATURE(f, H5FD_FEAT_IGNORE_DRVRINFO)) {
+                /* Check for driver info message */
+                H5_CHECKED_ASSIGN(driver_size, size_t, H5FD_sb_size(f->shared->lf), hsize_t);
+                if(driver_size > 0) {
+                    H5O_drvinfo_t drvinfo;      /* Driver info */
+                    uint8_t dbuf[H5F_MAX_DRVINFOBLOCK_SIZE];  /* Driver info block encoding buffer */
 
-        /* Read in the shared OH message information if there is any */
-        if(H5SM_get_info(&ext_loc, c_plist, dxpl_id) < 0)
-            HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "unable to read SOHM table information")
-
-        /* Check for the extension having a 'v1 B-tree "K"' message */
-        if((status = H5O_msg_exists(&ext_loc, H5O_BTREEK_ID, dxpl_id)) < 0)
-            HGOTO_ERROR(H5E_FILE, H5E_CANTGET, NULL, "unable to read object header")
-        if(status) {
-            /* Retrieve the 'v1 B-tree "K"' structure */
-            if(NULL == H5O_msg_read(&ext_loc, H5O_BTREEK_ID, &btreek, dxpl_id))
-                HGOTO_ERROR(H5E_FILE, H5E_CANTGET, NULL, "v1 B-tree 'K' info message not present")
-
-            /* Set non-default v1 B-tree 'K' value info from file */
-            sblock->btree_k[H5B_CHUNK_ID] = btreek.btree_k[H5B_CHUNK_ID];
-            sblock->btree_k[H5B_SNODE_ID] = btreek.btree_k[H5B_SNODE_ID];
-            sblock->sym_leaf_k = btreek.sym_leaf_k;
-
-            /* Set non-default v1 B-tree 'K' values in the property list */
-            if(H5P_set(c_plist, H5F_CRT_BTREE_RANK_NAME, btreek.btree_k) < 0)
-                HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, NULL, "unable to set rank for btree internal nodes")
-            if(H5P_set(c_plist, H5F_CRT_SYM_LEAF_NAME, &btreek.sym_leaf_k) < 0)
-                HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, NULL, "unable to set rank for symbol table leaf nodes")
-        } /* end if */
+                    /* Sanity check */
+                    HDassert(driver_size <= H5F_MAX_DRVINFOBLOCK_SIZE);
 
-        /* Check for the extension having a 'free-space manager info' message */
-        if((status = H5O_msg_exists(&ext_loc, H5O_FSINFO_ID, dxpl_id)) < 0)
-            HGOTO_ERROR(H5E_FILE, H5E_CANTGET, NULL, "unable to check object header")
-        if(status) {
-            H5O_fsinfo_t fsinfo;    /* Free-space manager info message from superblock extension */
-
-            /* Retrieve the 'free-space manager info' structure */
-	    if(NULL == H5O_msg_read(&ext_loc, H5O_FSINFO_ID, &fsinfo, dxpl_id))
-                HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, NULL, "unable to get free-space manager info message")
-
-	    if(shared->fs_strategy != fsinfo.strategy) {
-		shared->fs_strategy = fsinfo.strategy;
-
-		/* Set non-default strategy in the property list */
-		if(H5P_set(c_plist, H5F_CRT_FILE_SPACE_STRATEGY_NAME, &fsinfo.strategy) < 0)
-		    HGOTO_ERROR(H5E_FILE, H5E_CANTSET, NULL, "unable to set file space strategy")
-	    } /* end if */
-	    if(shared->fs_threshold != fsinfo.threshold) {
-		shared->fs_threshold = fsinfo.threshold;
-
-		/* Set non-default threshold in the property list */
-		if(H5P_set(c_plist, H5F_CRT_FREE_SPACE_THRESHOLD_NAME, &fsinfo.threshold) < 0)
-		    HGOTO_ERROR(H5E_FILE, H5E_CANTSET, NULL, "unable to set file space strategy")
-	    } /* end if */
-
-	    /* set free-space manager addresses */
-	    shared->fs_addr[0] = HADDR_UNDEF;
-	    for(u = 1; u < NELMTS(f->shared->fs_addr); u++)
-		shared->fs_addr[u] = fsinfo.fs_addr[u-1];
-        } /* end if */
+                    /* Encode driver-specific data */
+                    if(H5FD_sb_encode(f->shared->lf, drvinfo.name, dbuf) < 0)
+                        HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, FAIL, "unable to encode driver information")
 
-        /* Close superblock extension */
-        if(H5F_super_ext_close(f, &ext_loc, dxpl_id, FALSE) < 0)
-	    HGOTO_ERROR(H5E_FILE, H5E_CANTRELEASE, NULL, "unable to close file's superblock extension")
-    } /* end if */
+                    /* Write driver info information to the superblock extension */
+                    drvinfo.len = driver_size;
+                    drvinfo.buf = dbuf;
+                    if(H5O_msg_write(&ext_loc, H5O_DRVINFO_ID, H5O_MSG_FLAG_DONTSHARE, H5O_UPDATE_TIME, &drvinfo, dxpl_id) < 0)
+                        HGOTO_ERROR(H5E_FILE, H5E_WRITEERROR, FAIL, "unable to update driver info header message")
+                } /* end if */
+            } /* end if */
 
-    /* Set return value */
-    ret_value = sblock;
+            /* Close the superblock extension object header */
+            if(H5F_super_ext_close((H5F_t *)f, &ext_loc, dxpl_id, FALSE) < 0)
+                HGOTO_ERROR(H5E_FILE, H5E_CANTCLOSEOBJ, FAIL, "unable to close file's superblock extension")
+        } /* end if */
+    } /* end if */
 
 done:
-    /* Release the [possibly partially initialized] superblock on errors */
-    if(!ret_value && sblock)
-        if(H5F__super_free(sblock) < 0)
-            HDONE_ERROR(H5E_FILE, H5E_CANTFREE, NULL, "unable to destroy superblock data")
-
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5F_sblock_load() */
+} /* end H5FS_cache_superblock_pre_serialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:    H5F_sblock_flush
+ * Function:	H5F__cache_superblock_serialize
  *
- * Purpose:     Flushes the superblock.
+ * Purpose:	Flushes a dirty object to disk.
  *
- * Return:      Success:        SUCCEED
- *              Failure:        NULL
+ * Return:	Non-negative on success/Negative on failure
  *
- * Programmer:  Mike McGreevy
- *              mamcgree@hdfgroup.org
- *              April 8, 2009
+ * Programmer:	Quincey Koziol
+ *		koziol@hdfgroup.org
+ *		July 19 2013
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5F_sblock_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t H5_ATTR_UNUSED addr,
-    H5F_super_t *sblock)
+H5F__cache_superblock_serialize(const H5F_t *f, void *_image, size_t H5_ATTR_UNUSED len,
+    void *_thing)
 {
-    herr_t          ret_value = SUCCEED;
+    H5F_super_t *sblock = (H5F_super_t *)_thing;      /* Pointer to the object */
+    uint8_t *image = (uint8_t *)_image;         /* Pointer into raw data buffer */
+    haddr_t rel_eof;            /* Relative EOF for file */
+    herr_t ret_value = SUCCEED; /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
-    /* check arguments */
+    /* Sanity check */
     HDassert(f);
-    HDassert(H5F_addr_eq(addr, 0));
+    HDassert(image);
     HDassert(sblock);
-    
+
     /* Assert that the superblock is marked as being flushed last (and 
        collectively in parallel) */
     /* (We'll rely on the cache to make sure it actually *is* flushed
@@ -656,301 +619,403 @@ H5F_sblock_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t H5_ATTR_UNUSE
     HDassert(sblock->cache_info.flush_me_collectively);
 #endif
 
-    if(sblock->cache_info.is_dirty) {
-        H5P_genplist_t *dxpl;               /* DXPL object */
-        uint8_t         buf[H5F_MAX_SUPERBLOCK_SIZE + H5F_MAX_DRVINFOBLOCK_SIZE];  /* Superblock & driver info blockencoding buffer */
-        uint8_t        *p;                  /* Ptr into encoding buffer */
-        haddr_t         rel_eof;            /* Relative EOF for file */
-        size_t          superblock_size;    /* Size of superblock, in bytes */
-        size_t          driver_size;        /* Size of driver info block (bytes)*/
+    /* Encode the common portion of the file superblock for all versions */
+    HDmemcpy(image, H5F_SIGNATURE, (size_t)H5F_SIGNATURE_LEN);
+    image += H5F_SIGNATURE_LEN;
+    *image++ = (uint8_t)sblock->super_vers;
 
-        /* Encode the common portion of the file superblock for all versions */
-        p = buf;
-        HDmemcpy(p, H5F_SIGNATURE, (size_t)H5F_SIGNATURE_LEN);
-        p += H5F_SIGNATURE_LEN;
-        *p++ = (uint8_t)sblock->super_vers;
+    /* Check for older version of superblock format */
+    if(sblock->super_vers < HDF5_SUPERBLOCK_VERSION_2) {
+        *image++ = (uint8_t)HDF5_FREESPACE_VERSION;     /* (hard-wired) */
+        *image++ = (uint8_t)HDF5_OBJECTDIR_VERSION;     /* (hard-wired) */
+        *image++ = 0;   /* reserved*/
 
-        /* Check for older version of superblock format */
-        if(sblock->super_vers < HDF5_SUPERBLOCK_VERSION_2) {
-            *p++ = (uint8_t)HDF5_FREESPACE_VERSION;     /* (hard-wired) */
-            *p++ = (uint8_t)HDF5_OBJECTDIR_VERSION;     /* (hard-wired) */
-            *p++ = 0;   /* reserved*/
+        *image++ = (uint8_t)HDF5_SHAREDHEADER_VERSION;  /* (hard-wired) */
+        *image++ = sblock->sizeof_addr;
+        *image++ = sblock->sizeof_size;
+        *image++ = 0;   /* reserved */
 
-            *p++ = (uint8_t)HDF5_SHAREDHEADER_VERSION;  /* (hard-wired) */
-            *p++ = (uint8_t)H5F_SIZEOF_ADDR(f);
-            *p++ = (uint8_t)H5F_SIZEOF_SIZE(f);
-            *p++ = 0;   /* reserved */
+        UINT16ENCODE(image, sblock->sym_leaf_k);
+        UINT16ENCODE(image, sblock->btree_k[H5B_SNODE_ID]);
+        UINT32ENCODE(image, (uint32_t)sblock->status_flags);
 
-            UINT16ENCODE(p, sblock->sym_leaf_k);
-            UINT16ENCODE(p, sblock->btree_k[H5B_SNODE_ID]);
-            UINT32ENCODE(p, (uint32_t)sblock->status_flags);
+        /*
+         * Versions of the superblock >0 have the indexed storage B-tree
+         * internal 'K' value stored
+         */
+        if(sblock->super_vers > HDF5_SUPERBLOCK_VERSION_DEF) {
+            UINT16ENCODE(image, sblock->btree_k[H5B_CHUNK_ID]);
+            *image++ = 0;   /*reserved */
+            *image++ = 0;   /*reserved */
+        } /* end if */
 
-            /*
-             * Versions of the superblock >0 have the indexed storage B-tree
-             * internal 'K' value stored
-             */
-            if(sblock->super_vers > HDF5_SUPERBLOCK_VERSION_DEF) {
-                UINT16ENCODE(p, sblock->btree_k[H5B_CHUNK_ID]);
-                *p++ = 0;   /*reserved */
-                *p++ = 0;   /*reserved */
-            } /* end if */
+        /* Encode the base address */
+        H5F_addr_encode(f, &image, sblock->base_addr);
 
-            /* Encode the base address */
-            H5F_addr_encode(f, &p, sblock->base_addr);
-
-            /* Encode the address of global free-space index */
-            H5F_addr_encode(f, &p, sblock->ext_addr);
-
-            /* Encode the end-of-file address. Note that at this point in time,
-             * the EOF value itself may not be reflective of the file's size, as
-             * we will eventually truncate the file to match the EOA value. As
-             * such, use the EOA value in its place, knowing that the current EOF
-             * value will ultimately match it. */
-            if ((rel_eof = H5FD_get_eoa(f->shared->lf, H5FD_MEM_SUPER)) == HADDR_UNDEF)
-                HGOTO_ERROR(H5E_RESOURCE, H5E_CANTGET, FAIL, "driver get_eoa request failed")
-            H5F_addr_encode(f, &p, (rel_eof + sblock->base_addr));
-
-            /* Encode the driver informaton block address */
-            H5F_addr_encode(f, &p, sblock->driver_addr);
-
-            /* Encode the root group object entry, including the cached stab info */
-            if(H5G_ent_encode(f, &p, sblock->root_ent) < 0)
-                HGOTO_ERROR(H5E_FILE, H5E_CANTENCODE, FAIL, "can't encode root group symbol table entry")
-
-            /* Encode the driver information block. */
-            H5_CHECKED_ASSIGN(driver_size, size_t, H5FD_sb_size(f->shared->lf), hsize_t);
-
-            /* Checking whether driver block address is defined here is to handle backward
-             * compatibility.  If the file was created with v1.6 library or earlier and no
-             * driver info block was written in the superblock, we don't write it either even
-             * though there's some driver info.  Otherwise, the driver block extended will
-             * overwrite the (meta)data right after the superblock. This situation happens to
-             * the family driver particularly.  SLU - 2009/3/24
-             */
-            if(driver_size > 0 && H5F_addr_defined(sblock->driver_addr)) {
-                char driver_name[9];    /* Name of driver, for driver info block */
-                uint8_t *dbuf = p;      /* Pointer to beginning of driver info */
+        /* Encode the address of global free-space index */
+        H5F_addr_encode(f, &image, sblock->ext_addr);
 
-                /* Encode the driver information block */
-                *p++ = HDF5_DRIVERINFO_VERSION_0; /* Version */
-                *p++ = 0; /* reserved */
-                *p++ = 0; /* reserved */
-                *p++ = 0; /* reserved */
+        /* Encode the end-of-file address. Note that at this point in time,
+         * the EOF value itself may not be reflective of the file's size, as
+         * we will eventually truncate the file to match the EOA value. As
+         * such, use the EOA value in its place, knowing that the current EOF
+         * value will ultimately match it. */
+        if ((rel_eof = H5FD_get_eoa(f->shared->lf, H5FD_MEM_SUPER)) == HADDR_UNDEF)
+            HGOTO_ERROR(H5E_RESOURCE, H5E_CANTGET, FAIL, "driver get_eoa request failed")
+        H5F_addr_encode(f, &image, (rel_eof + sblock->base_addr));
 
-                /* Driver info size, excluding header */
-                UINT32ENCODE(p, driver_size);
+        /* Encode the driver informaton block address */
+        H5F_addr_encode(f, &image, sblock->driver_addr);
 
-                /* Encode driver-specific data */
-                if(H5FD_sb_encode(f->shared->lf, driver_name, dbuf + H5F_DRVINFOBLOCK_HDR_SIZE) < 0)
-                    HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, FAIL, "unable to encode driver information")
+        /* Encode the root group object entry, including the cached stab info */
+        if(H5G_ent_encode(f, &image, sblock->root_ent) < 0)
+            HGOTO_ERROR(H5E_FILE, H5E_CANTENCODE, FAIL, "can't encode root group symbol table entry")
 
-                /* Store driver name (set in 'H5FD_sb_encode' call above) */
-                HDmemcpy(p, driver_name, (size_t)8);
+        /* NOTE: Driver info block is handled separately */
 
-                /* Advance buffer pointer past name & variable-sized portion of driver info */
-                /* (for later use in computing the superblock size) */
-                p += 8 + driver_size;
-            } /* end if */
-        } /* end if */
-        else {
-            uint32_t        chksum;                 /* Checksum temporary variable      */
-            H5O_loc_t       *root_oloc;             /* Pointer to root group's object location */
+    } /* end if */
+    else { /* sblock->super_vers >= HDF5_SUPERBLOCK_VERSION_2 */
+        uint32_t        chksum;                 /* Checksum temporary variable      */
+        H5O_loc_t       *root_oloc;             /* Pointer to root group's object location */
 
-            /* Size of file addresses & offsets, and status flags */
-            *p++ = (uint8_t)H5F_SIZEOF_ADDR(f);
-            *p++ = (uint8_t)H5F_SIZEOF_SIZE(f);
-            *p++ = sblock->status_flags;
+        /* Size of file addresses & offsets, and status flags */
+        *image++ = sblock->sizeof_addr;
+        *image++ = sblock->sizeof_size;
+        *image++ = sblock->status_flags;
 
-            /* Encode the base address */
-            H5F_addr_encode(f, &p, sblock->base_addr);
+        /* Encode the base address */
+        H5F_addr_encode(f, &image, sblock->base_addr);
 
-            /* Encode the address of the superblock extension */
-            H5F_addr_encode(f, &p, sblock->ext_addr);
+        /* Encode the address of the superblock extension */
+        H5F_addr_encode(f, &image, sblock->ext_addr);
 
-            /* At this point in time, the EOF value itself may
-             * not be reflective of the file's size, since we'll eventually
-             * truncate it to match the EOA value. As such, use the EOA value
-             * in its place, knowing that the current EOF value will
-             * ultimately match it. */
-            if ((rel_eof = H5FD_get_eoa(f->shared->lf, H5FD_MEM_SUPER)) == HADDR_UNDEF)
-                HGOTO_ERROR(H5E_RESOURCE, H5E_CANTGET, FAIL, "driver get_eoa request failed")
-            H5F_addr_encode(f, &p, (rel_eof + sblock->base_addr));
+        /* At this point in time, the EOF value itself may
+         * not be reflective of the file's size, since we'll eventually
+         * truncate it to match the EOA value. As such, use the EOA value
+         * in its place, knowing that the current EOF value will
+         * ultimately match it. */
+        if ((rel_eof = H5FD_get_eoa(f->shared->lf, H5FD_MEM_SUPER)) == HADDR_UNDEF)
+            HGOTO_ERROR(H5E_RESOURCE, H5E_CANTGET, FAIL, "driver get_eoa request failed")
+        H5F_addr_encode(f, &image, (rel_eof + sblock->base_addr));
 
-            /* Retrieve information for root group */
-            if(NULL == (root_oloc = H5G_oloc(f->shared->root_grp)))
-                HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, FAIL, "unable to retrieve root group information")
+        /* Retrieve information for root group */
+        if(NULL == (root_oloc = H5G_oloc(f->shared->root_grp)))
+            HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, FAIL, "unable to retrieve root group information")
 
-            /* Encode address of root group's object header */
-            H5F_addr_encode(f, &p, root_oloc->addr);
+        /* Encode address of root group's object header */
+        H5F_addr_encode(f, &image, root_oloc->addr);
 
-            /* Compute superblock checksum */
-            chksum = H5_checksum_metadata(buf, ((size_t)H5F_SUPERBLOCK_SIZE(sblock->super_vers, f) - H5F_SIZEOF_CHKSUM), 0);
+        /* Compute superblock checksum */
+        chksum = H5_checksum_metadata(_image, ((size_t)H5F_SUPERBLOCK_SIZE(sblock) - H5F_SIZEOF_CHKSUM), 0);
 
-            /* Superblock checksum */
-            UINT32ENCODE(p, chksum);
+        /* Superblock checksum */
+        UINT32ENCODE(image, chksum);
 
-            /* Sanity check */
-            HDassert((size_t)(p - buf) == (size_t)H5F_SUPERBLOCK_SIZE(sblock->super_vers, f));
-        } /* end else */
+        /* Sanity check */
+        HDassert((size_t)(image - (uint8_t *)_image) == (size_t)H5F_SUPERBLOCK_SIZE(sblock));
+    } /* end else */
 
-        /* Retrieve the total size of the superblock info */
-        H5_CHECKED_ASSIGN(superblock_size, size_t, (p - buf), ptrdiff_t);
+    /* Sanity check */
+    HDassert((size_t)(image - (uint8_t *)_image) == len);
 
-        /* Double check we didn't overrun the block (unlikely) */
-        HDassert(superblock_size <= sizeof(buf));
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5F__cache_superblock_serialize() */
 
-        /* Get the DXPL plist object for DXPL ID */
-        if(NULL == (dxpl = (H5P_genplist_t *)H5I_object(dxpl_id)))
-            HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "can't get property list")
+
+/*-------------------------------------------------------------------------
+ * Function:	H5F__cache_superblock_free_icr
+ *
+ * Purpose:	Destroy/release an "in core representation" of a data
+ *              structure
+ *
+ * Note:	The metadata cache sets the object's cache_info.magic to
+ *		H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC before calling a free_icr
+ *		callback (checked in assert).
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              July 20, 2013
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5F__cache_superblock_free_icr(void *_thing)
+{
+    H5F_super_t *sblock = (H5F_super_t *)_thing;        /* Pointer to the object */
+    herr_t ret_value = SUCCEED;         /* Return value */
 
-        /* Write superblock */
-        /* (always at relative address 0) */
-        if(H5FD_write(f->shared->lf, dxpl, H5FD_MEM_SUPER, (haddr_t)0, superblock_size, buf) < 0)
-            HGOTO_ERROR(H5E_IO, H5E_WRITEERROR, FAIL, "unable to write superblock")
+    FUNC_ENTER_STATIC
 
-        /* Check for newer version of superblock format & superblock extension */
-        if(sblock->super_vers >= HDF5_SUPERBLOCK_VERSION_2 && H5F_addr_defined(sblock->ext_addr)) {
-            H5O_loc_t 	ext_loc;        /* "Object location" for superblock extension */
+    /* Sanity check */
+    HDassert(sblock);
+    HDassert(sblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC);
+    HDassert(sblock->cache_info.type == H5AC_SUPERBLOCK);
 
-            /* Open the superblock extension's object header */
-            if(H5F_super_ext_open(f, sblock->ext_addr, &ext_loc) < 0)
-                HGOTO_ERROR(H5E_FILE, H5E_CANTOPENOBJ, FAIL, "unable to open file's superblock extension")
+    /* Destroy superblock */
+    if(H5F__super_free(sblock) < 0)
+        HGOTO_ERROR(H5E_BTREE, H5E_CANTFREE, FAIL, "unable to free superblock")
 
-            /* Check for ignoring the driver info for this file */
-            if(!H5F_HAS_FEATURE(f, H5FD_FEAT_IGNORE_DRVRINFO)) {
-                /* Check for driver info message */
-                H5_CHECKED_ASSIGN(driver_size, size_t, H5FD_sb_size(f->shared->lf), hsize_t);
-                if(driver_size > 0) {
-                    H5O_drvinfo_t drvinfo;      /* Driver info */
-                    uint8_t dbuf[H5F_MAX_DRVINFOBLOCK_SIZE];  /* Driver info block encoding buffer */
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5F__cache_superblock_free_icr() */
 
-                    /* Sanity check */
-                    HDassert(driver_size <= H5F_MAX_DRVINFOBLOCK_SIZE);
+
+/*-------------------------------------------------------------------------
+ * Function:    H5F__cache_drvrinfo_get_load_size
+ *
+ * Purpose:     Compute the size of the data structure on disk.
+ *
+ * Return:      Non-negative on success/Negative on failure
+ *
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              July 20, 2013
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5F__cache_drvrinfo_get_load_size(const void H5_ATTR_UNUSED *udata, size_t *image_len)
+{
+    FUNC_ENTER_STATIC_NOERR
 
-                    /* Encode driver-specific data */
-                    if(H5FD_sb_encode(f->shared->lf, drvinfo.name, dbuf) < 0)
-                        HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, FAIL, "unable to encode driver information")
+    /* Check arguments */
+    HDassert(image_len);
 
-                    /* Write driver info information to the superblock extension */
-                    drvinfo.len = driver_size;
-                    drvinfo.buf = dbuf;
-                    if(H5O_msg_write(&ext_loc, H5O_DRVINFO_ID, H5O_MSG_FLAG_DONTSHARE, H5O_UPDATE_TIME, &drvinfo, dxpl_id) < 0)
-                        HGOTO_ERROR(H5E_FILE, H5E_WRITEERROR, FAIL, "unable to update driver info header message")
+    /* Set the initial image length size */
+    *image_len = H5F_DRVINFOBLOCK_HDR_SIZE;     /* Fixed size portion of driver info block */
 
-                } /* end if */
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5F__cache_drvrinfo_get_load_size() */
 
-            } /* end if */
+
+/*-------------------------------------------------------------------------
+ * Function:	H5F__cache_drvrinfo_deserialize
+ *
+ * Purpose:	Loads an object from the disk.
+ *
+ * Return:	Success:	Pointer to a new B-tree.
+ *		Failure:	NULL
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@hdfgroup.org
+ *		July 20 2013
+ *
+ *-------------------------------------------------------------------------
+ */
+static void *
+H5F__cache_drvrinfo_deserialize(const void *_image, size_t len, void *_udata,
+    hbool_t H5_ATTR_UNUSED *dirty)
+{
+    H5O_drvinfo_t       *drvinfo = NULL; /* Driver info */
+    H5F_drvrinfo_cache_ud_t *udata = (H5F_drvrinfo_cache_ud_t *)_udata;     /* User data */
+    const uint8_t	*image = (const uint8_t *)_image;       /* Pointer into raw data buffer */
+    char                drv_name[9];    /* Name of driver */
+    unsigned            drv_vers;       /* Version of driver info block */
+    H5O_drvinfo_t       *ret_value;     /* Return value */
 
-            /* Close the superblock extension object header */
-            if(H5F_super_ext_close(f, &ext_loc, dxpl_id, FALSE) < 0)
-                HGOTO_ERROR(H5E_FILE, H5E_CANTCLOSEOBJ, FAIL, "unable to close file's superblock extension")
-        } /* end if */
+    FUNC_ENTER_STATIC
+
+    /* Sanity check */
+    HDassert(image);
+    HDassert(len >= H5F_DRVINFOBLOCK_HDR_SIZE);
+    HDassert(udata);
+    HDassert(udata->f);
+
+    /* Allocate space for the driver info */
+    if(NULL == (drvinfo = (H5O_drvinfo_t *)H5MM_calloc(sizeof(H5O_drvinfo_t))))
+	HGOTO_ERROR(H5E_FILE, H5E_CANTALLOC, NULL, "memory allocation failed for driver info message")
+
+    /* Version number */
+    drv_vers = *image++;
+    if(drv_vers != HDF5_DRIVERINFO_VERSION_0)
+        HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad driver information block version number")
+
+    image += 3; /* reserved bytes */
+
+    /* Driver info size */
+    UINT32DECODE(image, drvinfo->len);
+
+    /* Driver name and/or version */
+    HDstrncpy(drv_name, (const char *)image, (size_t)8);
+    drv_name[8] = '\0';
+    image += 8; /* advance past name/version */
+
+    /* Handle metadata cache retry for variable-sized portion of the driver info block */
+    if(len != (H5F_DRVINFOBLOCK_HDR_SIZE + drvinfo->len)) {
+        /* Sanity check */
+        HDassert(len == H5F_DRVINFOBLOCK_HDR_SIZE);
+
+        /* extend the eoa if required so that we can read the complete driver info block */
+        {
+            haddr_t eoa;
+            haddr_t min_eoa;
+
+            /* get current eoa... */
+	    if ((eoa = H5FD_get_eoa(udata->f->shared->lf, H5FD_MEM_SUPER)) == HADDR_UNDEF)
+                HGOTO_ERROR(H5E_RESOURCE, H5E_CANTGET, NULL, "driver get_eoa request failed")
+
+            /* ... if it is too small, extend it. */
+            min_eoa = udata->driver_addr + H5F_DRVINFOBLOCK_HDR_SIZE + drvinfo->len;
+
+            if ( H5F_addr_gt(min_eoa, eoa) )
+                if(H5FD_set_eoa(udata->f->shared->lf, H5FD_MEM_SUPER, min_eoa) < 0)
+                    HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, NULL, \
+                        "set end of space allocation request failed")
+        }        
 
-        /* Reset the dirty flag.  */
-        sblock->cache_info.is_dirty = FALSE;
+    } /* end if */
+    else {
+        /* Validate and decode driver information */
+        if(H5FD_sb_load(udata->f->shared->lf, drv_name, image) < 0)
+            HGOTO_ERROR(H5E_FILE, H5E_CANTDECODE, NULL, "unable to decode driver information")
     } /* end if */
 
-    if(destroy)
-        if(H5F_sblock_dest(f, sblock) < 0)
-            HGOTO_ERROR(H5E_FSPACE, H5E_CLOSEERROR, FAIL, "can't close superblock")
+    /* Sanity check */
+    HDassert((size_t)(image - (const uint8_t *)_image) <= len);
+
+    /* Set return value */
+    ret_value = drvinfo;
 
 done:
+    /* Release the [possibly partially initialized] driver info message on error */
+    if(!ret_value && drvinfo)
+        H5MM_xfree(drvinfo);
+
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5F_sblock_flush() */
+} /* end H5F__cache_drvrinfo_deserialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:    H5F_sblock_dest
+ * Function:    H5F__cache_drvrinfo_image_len
  *
- * Purpose:     Frees memory used by the superblock.
+ * Purpose:     Compute the size of the data structure on disk.
  *
  * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:  Mike McGreevy
- *              April 8, 2009
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              July 20, 2013
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5F_sblock_dest(H5F_t H5_ATTR_UNUSED *f, H5F_super_t* sblock)
+H5F__cache_drvrinfo_image_len(const void *_thing, size_t *image_len,
+    hbool_t H5_ATTR_UNUSED *compressed_ptr, size_t H5_ATTR_UNUSED *compressed_image_len_ptr)
 {
-    herr_t ret_value = SUCCEED;         /* Return value */
+    const H5O_drvinfo_t *drvinfo = (const H5O_drvinfo_t *)_thing;       /* Pointer to the object */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC_NOERR
 
-    /* Sanity check */
-    HDassert(sblock);
+    /* Check arguments */
+    HDassert(drvinfo);
+    HDassert(drvinfo->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(drvinfo->cache_info.type == H5AC_DRVRINFO);
+    HDassert(image_len);
+    HDassert(compressed_ptr);
 
-    /* Free superblock */
-    if(H5F__super_free(sblock) < 0)
-        HGOTO_ERROR(H5E_FILE, H5E_CANTFREE, FAIL, "unable to destroy superblock")
+    /* Set the image length size */
+    *image_len = (size_t)(H5F_DRVINFOBLOCK_HDR_SIZE +   /* Fixed-size portion of driver info block */
+        drvinfo->len);                                  /* Variable-size portion of driver info block */
 
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5F_sblock_dest() */
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5F__cache_drvrinfo_image_len() */
 
 
 /*-------------------------------------------------------------------------
- * Function:    H5F_sblock_clear
+ * Function:	H5F__cache_drvrinfo_serialize
  *
- * Purpose:     Mark the superblock as no longer being dirty.
+ * Purpose:	Flushes a dirty object to disk.
  *
- * Return:      Non-negative on success/Negative on failure
+ * Return:	Non-negative on success/Negative on failure
  *
- * Programmer:  Mike McGreevy
- *              April 8, 2009
+ * Programmer:	Quincey Koziol
+ *		koziol@hdfgroup.org
+ *		July 20 2013
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5F_sblock_clear(H5F_t *f, H5F_super_t *sblock, hbool_t destroy)
+H5F__cache_drvrinfo_serialize(const H5F_t *f, void *_image, size_t len,
+    void *_thing)
 {
-    herr_t ret_value = SUCCEED;         /* Return value */
+    H5O_drvinfo_t *drvinfo = (H5O_drvinfo_t *)_thing;   /* Pointer to the object */
+    uint8_t *image = (uint8_t *)_image;         /* Pointer into raw data buffer */
+    uint8_t *dbuf;              /* Pointer to beginning of driver info */
+    herr_t ret_value = SUCCEED; /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
-    /*
-     * Check arguments.
-     */
-    HDassert(sblock);
+    /* check arguments */
+    HDassert(f);
+    HDassert(image);
+    HDassert(drvinfo);
+    HDassert(drvinfo->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(drvinfo->cache_info.type == H5AC_DRVRINFO);
+    HDassert(len == (size_t)(H5F_DRVINFOBLOCK_HDR_SIZE + drvinfo->len));
+
+    /* Save pointer to beginning of driver info */
+    dbuf = image;
+
+    /* Encode the driver information block */
+    *image++ = HDF5_DRIVERINFO_VERSION_0; /* Version */
+    *image++ = 0; /* reserved */
+    *image++ = 0; /* reserved */
+    *image++ = 0; /* reserved */
+
+    /* Driver info size, excluding header */
+    UINT32ENCODE(image, drvinfo->len);
 
-    /* Reset the dirty flag.  */
-    sblock->cache_info.is_dirty = FALSE;
+    /* Encode driver-specific data */
+    if(H5FD_sb_encode(f->shared->lf, (char *)image, dbuf + H5F_DRVINFOBLOCK_HDR_SIZE) < 0)
+        HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, FAIL, "unable to encode driver information")
 
-    if(destroy)
-        if(H5F_sblock_dest(f, sblock) < 0)
-            HGOTO_ERROR(H5E_FILE, H5E_CANTFREE, FAIL, "unable to delete superblock")
+    /* Advance buffer pointer past name & variable-sized portion of driver info */
+    image += 8 + drvinfo->len;
+
+    /* Sanity check */
+    HDassert((size_t)(image - (uint8_t *)_image) == len);
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5F_sblock_clear() */
+} /* H5F__cache_drvrinfo_serialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:    H5F_sblock_size
+ * Function:	H5F__cache_drvrinfo_free_icr
  *
- * Purpose:     Returns the size of the superblock encoded on disk.
+ * Purpose:	Destroy/release an "in core representation" of a data
+ *              structure
  *
- * Return:      Non-negative on success/Negative on failure
+ * Note:	The metadata cache sets the object's cache_info.magic to
+ *		H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC before calling a free_icr
+ *		callback (checked in assert).
  *
- * Programmer:  Mike McGreevy
- *              April 8, 2009
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              July 20, 2013
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5F_sblock_size(const H5F_t *f, const H5F_super_t *sblock, size_t *size_ptr)
+H5F__cache_drvrinfo_free_icr(void *_thing)
 {
-    FUNC_ENTER_NOAPI_NOINIT_NOERR
+    H5O_drvinfo_t *drvinfo = (H5O_drvinfo_t *)_thing;    /* Pointer to the object */
 
-    /* check arguments */
-    HDassert(f);
-    HDassert(sblock);
-    HDassert(size_ptr);
+    FUNC_ENTER_STATIC_NOERR
+
+    /* Check arguments */
+    HDassert(drvinfo);
+    HDassert(drvinfo->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC);
+    HDassert(drvinfo->cache_info.type == H5AC_DRVRINFO);
 
-    /* Set size value */
-    *size_ptr = (size_t)H5F_SUPERBLOCK_SIZE(sblock->super_vers, f);
+    /* Destroy driver info message */
+    H5MM_xfree(drvinfo);
 
     FUNC_LEAVE_NOAPI(SUCCEED)
-} /* end H5F_sblock_size() */
+} /* H5F__cache_drvrinfo_free_icr() */
 
diff --git a/src/H5Gcache.c b/src/H5Gcache.c
index bedceb6..f765b41 100644
--- a/src/H5Gcache.c
+++ b/src/H5Gcache.c
@@ -46,7 +46,6 @@
 /****************/
 
 #define H5G_NODE_VERS           1       /* Symbol table node version number   */
-#define H5G_NODE_BUF_SIZE       512     /* Size of stack buffer for serialized nodes */
 
 
 /******************/
@@ -64,12 +63,14 @@
 /********************/
 
 /* Metadata cache (H5AC) callbacks */
-static H5G_node_t *H5G_node_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata);
-static herr_t H5G_node_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr,
-			     H5G_node_t *sym, unsigned *flags_ptr);
-static herr_t H5G_node_dest(H5F_t *f, H5G_node_t *sym);
-static herr_t H5G_node_clear(H5F_t *f, H5G_node_t *sym, hbool_t destroy);
-static herr_t H5G_node_size(const H5F_t *f, const H5G_node_t *sym, size_t *size_ptr);
+static herr_t H5G__cache_node_get_load_size(const void *udata, size_t *image_len);
+static void *H5G__cache_node_deserialize(const void *image, size_t len,
+    void *udata, hbool_t *dirty);
+static herr_t H5G__cache_node_image_len(const void *thing, size_t *image_len,
+    hbool_t *compressed_ptr, size_t *compressed_image_len_ptr);
+static herr_t H5G__cache_node_serialize(const H5F_t *f, void *image,
+    size_t len, void *thing);
+static herr_t H5G__cache_node_free_icr(void *thing);
 
 
 /*********************/
@@ -88,13 +89,19 @@ static herr_t H5G_node_size(const H5F_t *f, const H5G_node_t *sym, size_t *size_
 
 /* Symbol table nodes inherit cache-like properties from H5AC */
 const H5AC_class_t H5AC_SNODE[1] = {{
-    H5AC_SNODE_ID,
-    (H5AC_load_func_t)H5G_node_load,
-    (H5AC_flush_func_t)H5G_node_flush,
-    (H5AC_dest_func_t)H5G_node_dest,
-    (H5AC_clear_func_t)H5G_node_clear,
-    (H5AC_notify_func_t)NULL,
-    (H5AC_size_func_t)H5G_node_size,
+    H5AC_SNODE_ID,                      /* Metadata client ID */
+    "Symbol table node",                /* Metadata client name (for debugging) */
+    H5FD_MEM_BTREE,                     /* File space memory type for client */
+    H5AC__CLASS_NO_FLAGS_SET,           /* Client class behavior flags */
+    H5G__cache_node_get_load_size,      /* 'get_load_size' callback */
+    H5G__cache_node_deserialize,        /* 'deserialize' callback */
+    H5G__cache_node_image_len,          /* 'image_len' callback */
+    NULL,                               /* 'pre_serialize' callback */
+    H5G__cache_node_serialize,          /* 'serialize' callback */
+    NULL,                               /* 'notify' callback */
+    H5G__cache_node_free_icr,           /* 'free_icr' callback */
+    NULL,			        /* 'clear' callback */
+    NULL,                               /* 'fsf_size' callback */
 }};
 
 
@@ -106,42 +113,80 @@ H5FL_SEQ_EXTERN(H5G_entry_t);
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5G_node_load
+ * Function:    H5G__cache_node_get_load_size()
  *
- * Purpose:	Loads a symbol table node from the file.
+ * Purpose:	Determine the size of the on disk image of the node, and 
+ *		return this value in *image_len.
  *
- * Return:	Success:	Ptr to the new table.
+ *		Note that this computation requires access to the file pointer,
+ *		which is not provided in the parameter list for this callback.
+ *		Finesse this issue by passing in the file pointer twice to the
+ *		H5AC_protect() call -- once as the file pointer proper, and 
+ *		again as the user data.
+ *      
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
  *
- *		Failure:	NULL
- *
- * Programmer:	Robb Matzke
- *		matzke@llnl.gov
- *		Jun 23 1997
+ * Programmer:  John Mainzer
+ *              7/21/14
  *
  *-------------------------------------------------------------------------
  */
-static H5G_node_t *
-H5G_node_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata)
+static herr_t
+H5G__cache_node_get_load_size(const void *_udata, size_t *image_len)
 {
-    H5G_node_t		   *sym = NULL;
-    H5WB_t                 *wb = NULL;     /* Wrapped buffer for node data */
-    uint8_t                 node_buf[H5G_NODE_BUF_SIZE]; /* Buffer for node */
-    uint8_t		   *node;           /* Pointer to node buffer */
-    const uint8_t	   *p;
-    H5G_node_t		   *ret_value;	/*for error handling */
-
-    FUNC_ENTER_NOAPI_NOINIT
-
-    /*
-     * Check arguments.
-     */
+    const H5F_t	       *f = (const H5F_t *)_udata;   /* User data for callback */
+
+    FUNC_ENTER_STATIC_NOERR
+
+    /* Sanity checks */
     HDassert(f);
-    HDassert(H5F_addr_defined(addr));
-    HDassert(udata);
+    HDassert(image_len);
+
+    /* report image length */
+    *image_len = (size_t)(H5G_NODE_SIZE(f));
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5G__cache_node_get_load_size() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5G__cache_node_deserialize
+ *
+ * Purpose:	Given a buffer containing the on disk image of a symbol table
+ *		node, allocate an instance of H5G_node_t, load the contence of the
+ *		image into it, and return a pointer to the instance.
+ *
+ *		Note that deserializing the image requires access to the file 
+ *		pointer, which is not included in the parameter list for this 
+ *		callback.  Finesse this issue by passing in the file pointer 
+ *		twice to the H5AC_protect() call -- once as the file pointer 
+ *		proper, and again as the user data
+ *
+ * Return:      Success:        Pointer to in core representation
+ *              Failure:        NULL
+ *
+ * Programmer:  John Mainzer
+ *              6/21/14
+ *
+ *-------------------------------------------------------------------------
+ */
+static void *
+H5G__cache_node_deserialize(const void *_image, size_t len, void *_udata,
+    hbool_t H5_ATTR_UNUSED *dirty)
+{
+    H5F_t                  *f = (H5F_t *)_udata;        /* User data for callback */
+    H5G_node_t             *sym = NULL; /* Symbol table node created */
+    const uint8_t          *image = (const uint8_t *)_image;    /* Pointer to image to deserialize */
+    void *                  ret_value;  /* Return value */
 
-    /*
-     * Initialize variables.
-     */
+    FUNC_ENTER_STATIC
+
+    /* Sanity checks */
+    HDassert(image);
+    HDassert(len > 0);
+    HDassert(f);
+    HDassert(dirty);
 
     /* Allocate symbol table data structures */
     if(NULL == (sym = H5FL_CALLOC(H5G_node_t)))
@@ -150,262 +195,177 @@ H5G_node_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata)
     if(NULL == (sym->entry = H5FL_SEQ_CALLOC(H5G_entry_t, (size_t)(2 * H5F_SYM_LEAF_K(f)))))
         HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed")
 
-    /* Wrap the local buffer for serialized node info */
-    if(NULL == (wb = H5WB_wrap(node_buf, sizeof(node_buf))))
-        HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, NULL, "can't wrap buffer")
-
-    /* Get a pointer to a buffer that's large enough for node */
-    if(NULL == (node = (uint8_t *)H5WB_actual(wb, sym->node_size)))
-        HGOTO_ERROR(H5E_SYM, H5E_NOSPACE, NULL, "can't get actual buffer")
-
-    /* Read the serialized symbol table node. */
-    if(H5F_block_read(f, H5FD_MEM_BTREE, addr, sym->node_size, dxpl_id, node) < 0)
-	HGOTO_ERROR(H5E_SYM, H5E_READERROR, NULL, "unable to read symbol table node")
-
-    /* Get temporary pointer to serialized node */
-    p = node;
-
     /* magic */
-    if(HDmemcmp(p, H5G_NODE_MAGIC, (size_t)H5_SIZEOF_MAGIC))
-        HGOTO_ERROR(H5E_SYM, H5E_CANTLOAD, NULL, "bad symbol table node signature")
-    p += H5_SIZEOF_MAGIC;
+    if(HDmemcmp(image, H5G_NODE_MAGIC, (size_t)H5_SIZEOF_MAGIC))
+        HGOTO_ERROR(H5E_SYM, H5E_BADVALUE, NULL, "bad symbol table node signature")
+    image += H5_SIZEOF_MAGIC;
 
     /* version */
-    if(H5G_NODE_VERS != *p++)
-        HGOTO_ERROR(H5E_SYM, H5E_CANTLOAD, NULL, "bad symbol table node version")
+    if(H5G_NODE_VERS != *image++)
+        HGOTO_ERROR(H5E_SYM, H5E_VERSION, NULL, "bad symbol table node version")
 
     /* reserved */
-    p++;
+    image++;
 
     /* number of symbols */
-    UINT16DECODE(p, sym->nsyms);
+    UINT16DECODE(image, sym->nsyms);
 
     /* entries */
-    if(H5G__ent_decode_vec(f, &p, sym->entry, sym->nsyms) < 0)
+    if(H5G__ent_decode_vec(f, &image, sym->entry, sym->nsyms) < 0)
         HGOTO_ERROR(H5E_SYM, H5E_CANTLOAD, NULL, "unable to decode symbol table entries")
 
     /* Set return value */
     ret_value = sym;
 
 done:
-    /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-        HDONE_ERROR(H5E_SYM, H5E_CLOSEERROR, NULL, "can't close wrapped buffer")
     if(!ret_value)
         if(sym && H5G__node_free(sym) < 0)
             HDONE_ERROR(H5E_SYM, H5E_CANTFREE, NULL, "unable to destroy symbol table node")
 
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5G_node_load() */
+} /* end H5G__cache_node_deserialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5G_node_flush
+ * Function:    H5G__cache_node_image_len
  *
- * Purpose:	Flush a symbol table node to disk.
+ * Purpose:     Compute the size of the data structure on disk and return
+ *              it in *image_len.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
  *
- * Programmer:	Robb Matzke
- *		matzke@llnl.gov
- *		Jun 23 1997
+ * Programmer:  John Mainzer
+ *              6/21/14
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5G_node_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5G_node_t *sym, unsigned H5_ATTR_UNUSED * flags_ptr)
+H5G__cache_node_image_len(const void *_thing, size_t *image_len,
+    hbool_t H5_ATTR_UNUSED *compressed_ptr, size_t H5_ATTR_UNUSED *compressed_image_len_ptr)
 {
-    H5WB_t     *wb = NULL;     /* Wrapped buffer for node data */
-    uint8_t     node_buf[H5G_NODE_BUF_SIZE]; /* Buffer for node */
-    herr_t      ret_value = SUCCEED;       /* Return value */
+    const H5G_node_t *sym = (const H5G_node_t *)_thing; /* Pointer to object */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC_NOERR
 
-    /*
-     * Check arguments.
-     */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
+    /* Sanity checks */
     HDassert(sym);
+    HDassert(sym->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(sym->cache_info.type == H5AC_SNODE);
+    HDassert(image_len);
 
-    /*
-     * Write the symbol node to disk.
-     */
-    if(sym->cache_info.is_dirty) {
-        uint8_t	*node;          /* Pointer to node buffer */
-        uint8_t	*p;             /* Pointer into raw data buffer */
-
-        /* Wrap the local buffer for serialized node info */
-        if(NULL == (wb = H5WB_wrap(node_buf, sizeof(node_buf))))
-            HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, FAIL, "can't wrap buffer")
-
-        /* Get a pointer to a buffer that's large enough for node */
-        if(NULL == (node = (uint8_t *)H5WB_actual(wb, sym->node_size)))
-            HGOTO_ERROR(H5E_SYM, H5E_NOSPACE, FAIL, "can't get actual buffer")
-
-        /* Get temporary pointer to serialized symbol table node */
-        p = node;
-
-        /* magic number */
-        HDmemcpy(p, H5G_NODE_MAGIC, (size_t)H5_SIZEOF_MAGIC);
-        p += H5_SIZEOF_MAGIC;
-
-        /* version number */
-        *p++ = H5G_NODE_VERS;
-
-        /* reserved */
-        *p++ = 0;
-
-        /* number of symbols */
-        UINT16ENCODE(p, sym->nsyms);
-
-        /* entries */
-        if(H5G__ent_encode_vec(f, &p, sym->entry, sym->nsyms) < 0)
-            HGOTO_ERROR(H5E_SYM, H5E_CANTENCODE, FAIL, "can't serialize")
-        HDmemset(p, 0, sym->node_size - (size_t)(p - node));
-
-	/* Write the serialized symbol table node. */
-        if(H5F_block_write(f, H5FD_MEM_BTREE, addr, sym->node_size, dxpl_id, node) < 0)
-            HGOTO_ERROR(H5E_SYM, H5E_WRITEERROR, FAIL, "unable to write symbol table node to the file")
-
-        /* Reset the node's dirty flag */
-        sym->cache_info.is_dirty = FALSE;
-    } /* end if */
+    *image_len = sym->node_size;
 
-    /*
-     * Destroy the symbol node?	 This might happen if the node is being
-     * preempted from the cache.
-     */
-    if(destroy)
-        if(H5G_node_dest(f, sym) < 0)
-	    HGOTO_ERROR(H5E_SYM, H5E_CANTFREE, FAIL, "unable to destroy symbol table node")
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5G__cache_node_image_len() */
 
-done:
-    /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-        HDONE_ERROR(H5E_SYM, H5E_CLOSEERROR, FAIL, "can't close wrapped buffer")
 
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5G_node_flush() */
+/*************************************/
+/* no H5G__cache_node_pre_serialize() */
+/*************************************/
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5G_node_dest
+ * Function:    H5G__cache_node_serialize
  *
- * Purpose:	Destroy a symbol table node in memory.
+ * Purpose:	Given a correctly sized buffer and an instace of H5G_node_t,
+ *		serialize the contents of the instance of H5G_node_t, and write
+ *		this data into the supplied buffer.  This buffer will be written
+ *		to disk.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Jan 15 2003
+ * Programmer:  John Mainzer
+ *              7/21/14
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5G_node_dest(H5F_t *f, H5G_node_t *sym)
+H5G__cache_node_serialize(const H5F_t *f, void *_image, size_t len,
+    void *_thing)
 {
-    herr_t ret_value = SUCCEED;         /* Return value */
+    H5G_node_t *sym = (H5G_node_t *)_thing;     /* Pointer to object */
+    uint8_t    *image = (uint8_t *)_image;      /* Pointer into raw data buffer */
+    herr_t      ret_value = SUCCEED;    /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
-    /*
-     * Check arguments.
-     */
+    /* Sanity checks */
     HDassert(f);
+    HDassert(image);
     HDassert(sym);
+    HDassert(sym->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(sym->cache_info.type == H5AC_SNODE);
+    HDassert(len == sym->node_size);
 
-    /* Verify that node is clean */
-    HDassert(sym->cache_info.is_dirty == FALSE);
+    /* magic number */
+    HDmemcpy(image, H5G_NODE_MAGIC, (size_t)H5_SIZEOF_MAGIC);
+    image += H5_SIZEOF_MAGIC;
 
-    /* If we're going to free the space on disk, the address must be valid */
-    HDassert(!sym->cache_info.free_file_space_on_destroy || H5F_addr_defined(sym->cache_info.addr));
+    /* version number */
+    *image++ = H5G_NODE_VERS;
 
-    /* Check for freeing file space for symbol table node */
-    if(sym->cache_info.free_file_space_on_destroy) {
-        /* Release the space on disk */
-        /* (XXX: Nasty usage of internal DXPL value! -QAK) */
-        if(H5MF_xfree(f, H5FD_MEM_BTREE, H5AC_dxpl_id, sym->cache_info.addr, (hsize_t)sym->node_size) < 0)
-            HGOTO_ERROR(H5E_SYM, H5E_CANTFREE, FAIL, "unable to free symbol table node")
-    } /* end if */
+    /* reserved */
+    *image++ = 0;
 
-    /* Destroy symbol table node */
-    if(H5G__node_free(sym) < 0)
-        HGOTO_ERROR(H5E_SYM, H5E_CANTFREE, FAIL, "unable to destroy symbol table node")
+    /* number of symbols */
+    UINT16ENCODE(image, sym->nsyms);
+
+    /* entries */
+    if(H5G__ent_encode_vec(f, &image, sym->entry, sym->nsyms) < 0)
+        HGOTO_ERROR(H5E_SYM, H5E_CANTENCODE, FAIL, "can't serialize")
+
+#ifdef H5_CLEAR_MEMORY
+    /* Clear rest of symbol table node */
+    HDmemset(image, 0, len - (size_t)(image - (uint8_t *)_image));
+#endif /* H5_CLEAR_MEMORY */
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5G_node_dest() */
+} /* end H5G__cache_node_serialize() */
+
+
+/***************************************/
+/* no H5G__cache_node_notify() function */
+/***************************************/
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5G_node_clear
+ * Function:    H5G__cache_node_free_icr
  *
- * Purpose:	Mark a symbol table node in memory as non-dirty.
+ * Purpose:	Destroys a symbol table node in memory.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Note:	The metadata cache sets the object's cache_info.magic to
+ *		H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC before calling a free_icr
+ *		callback (checked in assert).
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Mar 20 2003
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
+ *
+ * Programmer:  John Mainzer
+ *              6/21/14
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5G_node_clear(H5F_t *f, H5G_node_t *sym, hbool_t destroy)
+H5G__cache_node_free_icr(void *_thing)
 {
-    herr_t ret_value = SUCCEED;
+    H5G_node_t *sym = (H5G_node_t *)_thing;     /* Pointer to the object */
+    herr_t      ret_value = SUCCEED;    /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
-    /*
-     * Check arguments.
-     */
+    /* Sanity checks */
     HDassert(sym);
+    HDassert(sym->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC);
+    HDassert(sym->cache_info.type == H5AC_SNODE);
 
-    /* Reset the node's dirty flag */
-    sym->cache_info.is_dirty = FALSE;
-
-    /*
-     * Destroy the symbol node?	 This might happen if the node is being
-     * preempted from the cache.
-     */
-    if(destroy)
-        if(H5G_node_dest(f, sym) < 0)
-	    HGOTO_ERROR(H5E_SYM, H5E_CANTFREE, FAIL, "unable to destroy symbol table node")
+    /* Destroy symbol table node */
+    if(H5G__node_free(sym) < 0)
+        HGOTO_ERROR(H5E_SYM, H5E_CANTFREE, FAIL, "unable to destroy symbol table node")
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5G_node_clear() */
-
-
-/*-------------------------------------------------------------------------
- * Function:	H5G_node_size
- *
- * Purpose:	Compute the size in bytes of the specified instance of
- *		H5G_node_t on disk, and return it in *size_ptr.  On failure
- *		the value of size_ptr is undefined.
- *
- * Return:	Non-negative on success/Negative on failure
- *
- * Programmer:	John Mainzer
- *		5/13/04
- *
- *-------------------------------------------------------------------------
- */
-static herr_t
-H5G_node_size(const H5F_t H5_ATTR_UNUSED *f, const H5G_node_t *sym, size_t *size_ptr)
-{
-    FUNC_ENTER_NOAPI_NOINIT_NOERR
-
-    /*
-     * Check arguments.
-     */
-    HDassert(f);
-    HDassert(size_ptr);
-
-    *size_ptr = sym->node_size;
-
-    FUNC_LEAVE_NOAPI(SUCCEED)
-} /* H5G_node_size() */
+} /* end H5G__cache_node_free_icr() */
 
diff --git a/src/H5Gent.c b/src/H5Gent.c
index 3f243de..3809933 100644
--- a/src/H5Gent.c
+++ b/src/H5Gent.c
@@ -460,7 +460,7 @@ H5G__ent_convert(H5F_t *f, hid_t dxpl_id, H5HL_t *heap, const char *name,
                 targ_oloc.addr = lnk->u.hard.addr;
 
                 /* Get the object header */
-                if(NULL == (oh = H5O_protect(&targ_oloc, dxpl_id, H5AC_READ)))
+                if(NULL == (oh = H5O_protect(&targ_oloc, dxpl_id, H5AC__READ_ONLY_FLAG)))
                     HGOTO_ERROR(H5E_SYM, H5E_CANTPROTECT, FAIL, "unable to protect target object header")
 
                 /* Check if a symbol table message exists */
diff --git a/src/H5Gnode.c b/src/H5Gnode.c
index d695dac..cbb9a8e 100644
--- a/src/H5Gnode.c
+++ b/src/H5Gnode.c
@@ -541,7 +541,7 @@ H5G_node_found(H5F_t *f, hid_t dxpl_id, haddr_t addr, const void H5_ATTR_UNUSED
     /*
      * Load the symbol table node for exclusive access.
      */
-    if(NULL == (sn = (H5G_node_t *)H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, f, H5AC_READ)))
+    if(NULL == (sn = (H5G_node_t *)H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, f, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_SYM, H5E_CANTLOAD, FAIL, "unable to protect symbol table node")
 
     /* Get base address of heap */
@@ -647,7 +647,7 @@ H5G_node_insert(H5F_t *f, hid_t dxpl_id, haddr_t addr,
     /*
      * Load the symbol node.
      */
-    if(NULL == (sn = (H5G_node_t *)H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, f, H5AC_WRITE)))
+    if(NULL == (sn = (H5G_node_t *)H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, f, H5AC__NO_FLAGS_SET)))
 	HGOTO_ERROR(H5E_SYM, H5E_CANTLOAD, H5B_INS_ERROR, "unable to protect symbol table node")
 
     /* Get base address of heap */
@@ -691,7 +691,7 @@ H5G_node_insert(H5F_t *f, hid_t dxpl_id, haddr_t addr,
 	if(H5G_node_create(f, dxpl_id, H5B_INS_FIRST, NULL, NULL, NULL, new_node_p/*out*/) < 0)
 	    HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, H5B_INS_ERROR, "unable to split symbol table node")
 
-	if(NULL == (snrt = (H5G_node_t *)H5AC_protect(f, dxpl_id, H5AC_SNODE, *new_node_p, f, H5AC_WRITE)))
+	if(NULL == (snrt = (H5G_node_t *)H5AC_protect(f, dxpl_id, H5AC_SNODE, *new_node_p, f, H5AC__NO_FLAGS_SET)))
 	    HGOTO_ERROR(H5E_SYM, H5E_CANTLOAD, H5B_INS_ERROR, "unable to split symbol table node")
 
 	HDmemcpy(snrt->entry, sn->entry + H5F_SYM_LEAF_K(f),
@@ -808,7 +808,7 @@ H5G_node_remove(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_lt_key/*in,out*/,
     HDassert(udata && udata->common.heap);
 
     /* Load the symbol table */
-    if(NULL == (sn = (H5G_node_t *)H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, f, H5AC_WRITE)))
+    if(NULL == (sn = (H5G_node_t *)H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, f, H5AC__NO_FLAGS_SET)))
 	HGOTO_ERROR(H5E_SYM, H5E_CANTLOAD, H5B_INS_ERROR, "unable to protect symbol table node")
 
     /* "Normal" removal of a single entry from the symbol table node */
@@ -1001,7 +1001,7 @@ H5G__node_iterate(H5F_t *f, hid_t dxpl_id, const void H5_ATTR_UNUSED *_lt_key, h
     HDassert(udata && udata->heap);
 
     /* Protect the symbol table node & local heap while we iterate over entries */
-    if(NULL == (sn = (H5G_node_t *)H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, f, H5AC_READ)))
+    if(NULL == (sn = (H5G_node_t *)H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, f, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_SYM, H5E_CANTLOAD, H5_ITER_ERROR, "unable to load symbol table node")
 
     /*
@@ -1078,7 +1078,7 @@ H5G__node_sumup(H5F_t *f, hid_t dxpl_id, const void H5_ATTR_UNUSED *_lt_key, had
     HDassert(num_objs);
 
     /* Find the object node and add the number of symbol entries. */
-    if(NULL == (sn = (H5G_node_t *)H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, f, H5AC_READ)))
+    if(NULL == (sn = (H5G_node_t *)H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, f, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_SYM, H5E_CANTLOAD, H5_ITER_ERROR, "unable to load symbol table node")
 
     *num_objs += sn->nsyms;
@@ -1123,7 +1123,7 @@ H5G__node_by_idx(H5F_t *f, hid_t dxpl_id, const void H5_ATTR_UNUSED *_lt_key, ha
     HDassert(udata);
 
     /* Get a pointer to the symbol table node */
-    if(NULL == (sn = (H5G_node_t *)H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, f, H5AC_READ)))
+    if(NULL == (sn = (H5G_node_t *)H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, f, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_SYM, H5E_CANTLOAD, H5_ITER_ERROR, "unable to load symbol table node");
 
     /* Find the node, locate the object symbol table entry and retrieve the name */
@@ -1261,11 +1261,11 @@ H5G__node_copy(H5F_t *f, hid_t dxpl_id, const void H5_ATTR_UNUSED *_lt_key, hadd
     HDassert(udata);
 
     /* load the symbol table into memory from the source file */
-    if(NULL == (sn = (H5G_node_t *)H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, f, H5AC_READ)))
+    if(NULL == (sn = (H5G_node_t *)H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, f, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_SYM, H5E_CANTLOAD, H5_ITER_ERROR, "unable to load symbol table node")
 
     /* get the base address of the heap */
-    if(NULL == (heap = H5HL_protect(f, dxpl_id, udata->src_heap_addr, H5AC_READ)))
+    if(NULL == (heap = H5HL_protect(f, dxpl_id, udata->src_heap_addr, H5AC__READ_ONLY_FLAG)))
        HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, H5_ITER_ERROR, "unable to protect symbol name")
 
     /* copy object in this node one by one */
@@ -1420,7 +1420,7 @@ H5G__node_build_table(H5F_t *f, hid_t dxpl_id, const void H5_ATTR_UNUSED *_lt_ke
      * Save information about the symbol table node since we can't lock it
      * because we're about to call an application function.
      */
-    if(NULL == (sn = (H5G_node_t *)H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, f, H5AC_READ)))
+    if(NULL == (sn = (H5G_node_t *)H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, f, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_SYM, H5E_CANTLOAD, H5_ITER_ERROR, "unable to load symbol table node")
 
     /* Check if the link table needs to be extended */
@@ -1527,14 +1527,14 @@ H5G_node_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE * stream, int indent,
 
     /* Pin the heap down in memory */
     if(heap_addr > 0 && H5F_addr_defined(heap_addr))
-        if(NULL == (heap = H5HL_protect(f, dxpl_id, heap_addr, H5AC_READ)))
+        if(NULL == (heap = H5HL_protect(f, dxpl_id, heap_addr, H5AC__READ_ONLY_FLAG)))
             HGOTO_ERROR(H5E_SYM, H5E_CANTLOAD, FAIL, "unable to protect symbol table heap")
 
     /*
      * If we couldn't load the symbol table node, then try loading the
      * B-tree node.
      */
-    if(NULL == (sn = (H5G_node_t *)H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, f, H5AC_READ))) {
+    if(NULL == (sn = (H5G_node_t *)H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, f, H5AC__READ_ONLY_FLAG))) {
         H5G_bt_common_t	udata;		/*data to pass through B-tree	*/
 
         H5E_clear_stack(NULL); /* discard that error */
diff --git a/src/H5Gstab.c b/src/H5Gstab.c
index 4c338c9..08188ae 100644
--- a/src/H5Gstab.c
+++ b/src/H5Gstab.c
@@ -160,7 +160,7 @@ H5G__stab_create_components(H5F_t *f, H5O_stab_t *stab, size_t size_hint, hid_t
 	HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, FAIL, "can't create heap")
 
     /* Pin the heap down in memory */
-    if(NULL == (heap = H5HL_protect(f, dxpl_id, stab->heap_addr, H5AC_WRITE)))
+    if(NULL == (heap = H5HL_protect(f, dxpl_id, stab->heap_addr, H5AC__NO_FLAGS_SET)))
         HGOTO_ERROR(H5E_SYM, H5E_PROTECT, FAIL, "unable to protect symbol table heap")
 
     /* Insert name into the heap */
@@ -276,7 +276,7 @@ H5G__stab_insert_real(H5F_t *f, const H5O_stab_t *stab, const char *name,
     HDassert(obj_lnk);
 
     /* Pin the heap down in memory */
-    if(NULL == (heap = H5HL_protect(f, dxpl_id, stab->heap_addr, H5AC_WRITE)))
+    if(NULL == (heap = H5HL_protect(f, dxpl_id, stab->heap_addr, H5AC__NO_FLAGS_SET)))
         HGOTO_ERROR(H5E_SYM, H5E_PROTECT, FAIL, "unable to protect symbol table heap")
 
     /* Initialize data to pass through B-tree */
@@ -373,7 +373,7 @@ H5G__stab_remove(const H5O_loc_t *loc, hid_t dxpl_id, H5RS_str_t *grp_full_path_
         HGOTO_ERROR(H5E_SYM, H5E_BADMESG, FAIL, "not a symbol table")
 
     /* Pin the heap down in memory */
-    if(NULL == (heap = H5HL_protect(loc->file, dxpl_id, stab.heap_addr, H5AC_WRITE)))
+    if(NULL == (heap = H5HL_protect(loc->file, dxpl_id, stab.heap_addr, H5AC__NO_FLAGS_SET)))
         HGOTO_ERROR(H5E_SYM, H5E_PROTECT, FAIL, "unable to protect symbol table heap")
 
     /* Initialize data to pass through B-tree */
@@ -431,7 +431,7 @@ H5G__stab_remove_by_idx(const H5O_loc_t *grp_oloc, hid_t dxpl_id, H5RS_str_t *gr
         HGOTO_ERROR(H5E_SYM, H5E_BADMESG, FAIL, "not a symbol table")
 
     /* Pin the heap down in memory */
-    if(NULL == (heap = H5HL_protect(grp_oloc->file, dxpl_id, stab.heap_addr, H5AC_WRITE)))
+    if(NULL == (heap = H5HL_protect(grp_oloc->file, dxpl_id, stab.heap_addr, H5AC__NO_FLAGS_SET)))
         HGOTO_ERROR(H5E_SYM, H5E_PROTECT, FAIL, "unable to protect symbol table heap")
 
     /* Initialize data to pass through B-tree */
@@ -485,7 +485,7 @@ H5G__stab_delete(H5F_t *f, hid_t dxpl_id, const H5O_stab_t *stab)
     HDassert(H5F_addr_defined(stab->heap_addr));
 
     /* Pin the heap down in memory */
-    if(NULL == (heap = H5HL_protect(f, dxpl_id, stab->heap_addr, H5AC_WRITE)))
+    if(NULL == (heap = H5HL_protect(f, dxpl_id, stab->heap_addr, H5AC__NO_FLAGS_SET)))
         HGOTO_ERROR(H5E_SYM, H5E_PROTECT, FAIL, "unable to protect symbol table heap")
 
     /* Set up user data for B-tree deletion */
@@ -546,7 +546,7 @@ H5G__stab_iterate(const H5O_loc_t *oloc, hid_t dxpl_id, H5_iter_order_t order,
 	HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, FAIL, "unable to determine local heap address")
 
     /* Pin the heap down in memory */
-    if(NULL == (heap = H5HL_protect(oloc->file, dxpl_id, stab.heap_addr, H5AC_READ)))
+    if(NULL == (heap = H5HL_protect(oloc->file, dxpl_id, stab.heap_addr, H5AC__READ_ONLY_FLAG)))
         HGOTO_ERROR(H5E_SYM, H5E_PROTECT, FAIL, "unable to protect symbol table heap")
 
     /* Check on iteration order */
@@ -766,7 +766,7 @@ H5G__stab_get_name_by_idx(const H5O_loc_t *oloc, H5_iter_order_t order, hsize_t
 	HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, FAIL, "unable to determine local heap address")
 
     /* Pin the heap down in memory */
-    if(NULL == (heap = H5HL_protect(oloc->file, dxpl_id, stab.heap_addr, H5AC_READ)))
+    if(NULL == (heap = H5HL_protect(oloc->file, dxpl_id, stab.heap_addr, H5AC__READ_ONLY_FLAG)))
         HGOTO_ERROR(H5E_SYM, H5E_PROTECT, FAIL, "unable to protect symbol table heap")
 
     /* Remap index for decreasing iteration order */
@@ -888,7 +888,7 @@ H5G__stab_lookup(const H5O_loc_t *grp_oloc, const char *name, H5O_link_t *lnk,
         HGOTO_ERROR(H5E_SYM, H5E_BADMESG, FAIL, "can't read message")
 
     /* Pin the heap down in memory */
-    if(NULL == (heap = H5HL_protect(grp_oloc->file, dxpl_id, stab.heap_addr, H5AC_READ)))
+    if(NULL == (heap = H5HL_protect(grp_oloc->file, dxpl_id, stab.heap_addr, H5AC__READ_ONLY_FLAG)))
         HGOTO_ERROR(H5E_SYM, H5E_PROTECT, FAIL, "unable to protect symbol table heap")
 
     /* Set up user data to pass to 'find' operation callback */
@@ -989,7 +989,7 @@ H5G__stab_lookup_by_idx(const H5O_loc_t *grp_oloc, H5_iter_order_t order, hsize_
 	HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, FAIL, "unable to determine local heap address")
 
     /* Pin the heap down in memory */
-    if(NULL == (heap = H5HL_protect(grp_oloc->file, dxpl_id, stab.heap_addr, H5AC_READ)))
+    if(NULL == (heap = H5HL_protect(grp_oloc->file, dxpl_id, stab.heap_addr, H5AC__READ_ONLY_FLAG)))
         HGOTO_ERROR(H5E_SYM, H5E_PROTECT, FAIL, "unable to protect symbol table heap")
 
     /* Remap index for decreasing iteration order */
@@ -1081,10 +1081,10 @@ H5G__stab_valid(H5O_loc_t *grp_oloc, hid_t dxpl_id, H5O_stab_t *alt_stab)
     } /* end if */
 
     /* Check if the symbol table message's heap address is valid */
-    if(NULL == (heap = H5HL_protect(grp_oloc->file, dxpl_id, stab.heap_addr, H5AC_READ))) {
+    if(NULL == (heap = H5HL_protect(grp_oloc->file, dxpl_id, stab.heap_addr, H5AC__READ_ONLY_FLAG))) {
         /* Address is invalid, try the heap address in the alternate symbol
          * table message */
-        if(!alt_stab || NULL == (heap = H5HL_protect(grp_oloc->file, dxpl_id, alt_stab->heap_addr, H5AC_READ)))
+        if(!alt_stab || NULL == (heap = H5HL_protect(grp_oloc->file, dxpl_id, alt_stab->heap_addr, H5AC__READ_ONLY_FLAG)))
             HGOTO_ERROR(H5E_HEAP, H5E_NOTFOUND, FAIL, "unable to locate heap")
         else {
             /* The alternate symbol table's heap address is valid.  Adjust the
diff --git a/src/H5Gtest.c b/src/H5Gtest.c
index 89b4a37..1c0adea 100644
--- a/src/H5Gtest.c
+++ b/src/H5Gtest.c
@@ -637,7 +637,7 @@ H5G__verify_cached_stab_test(H5O_loc_t *grp_oloc, H5G_entry_t *ent)
         HGOTO_ERROR(H5E_BTREE, H5E_NOTFOUND, FAIL, "b-tree address is invalid")
 
     /* Verify that the heap address is valid */
-    if(NULL == (heap = H5HL_protect(grp_oloc->file, dxpl_id, stab.heap_addr, H5AC_READ)))
+    if(NULL == (heap = H5HL_protect(grp_oloc->file, dxpl_id, stab.heap_addr, H5AC__READ_ONLY_FLAG)))
         HGOTO_ERROR(H5E_HEAP, H5E_NOTFOUND, FAIL, "heap address is invalid")
 
 done:
@@ -686,7 +686,7 @@ H5G_verify_cached_stabs_test_cb(H5F_t *f, hid_t dxpl_id,
     HDassert(H5F_addr_defined(addr));
 
     /* Load the node */
-    if(NULL == (sn = (H5G_node_t *)H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, f, H5AC_READ)))
+    if(NULL == (sn = (H5G_node_t *)H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, f, H5AC__READ_ONLY_FLAG)))
         HGOTO_ERROR(H5E_SYM, H5E_CANTLOAD, H5_ITER_ERROR, "unable to load symbol table node")
 
     /* Check each target object to see if its stab message (if present) matches
@@ -701,7 +701,7 @@ H5G_verify_cached_stabs_test_cb(H5F_t *f, hid_t dxpl_id,
         targ_oloc.addr = sn->entry[i].header;
 
         /* Load target object header */
-        if(NULL == (targ_oh = H5O_protect(&targ_oloc, dxpl_id, H5AC_READ)))
+        if(NULL == (targ_oh = H5O_protect(&targ_oloc, dxpl_id, H5AC__READ_ONLY_FLAG)))
             HGOTO_ERROR(H5E_SYM, H5E_CANTPROTECT, H5_ITER_ERROR, "unable to protect target object header")
 
         /* Check if a symbol table message exists */
diff --git a/src/H5HF.c b/src/H5HF.c
index f57c5e2..0464da4 100644
--- a/src/H5HF.c
+++ b/src/H5HF.c
@@ -172,7 +172,7 @@ H5HF_create(H5F_t *f, hid_t dxpl_id, const H5HF_create_t *cparam)
         HGOTO_ERROR(H5E_HEAP, H5E_CANTALLOC, NULL, "memory allocation failed for fractal heap info")
 
     /* Lock the heap header into memory */
-    if(NULL == (hdr = H5HF_hdr_protect(f, dxpl_id, fh_addr, H5AC_WRITE)))
+    if(NULL == (hdr = H5HF_hdr_protect(f, dxpl_id, fh_addr, H5AC__NO_FLAGS_SET)))
         HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, NULL, "unable to protect fractal heap header")
 
     /* Point fractal heap wrapper at header and bump it's ref count */
@@ -231,7 +231,7 @@ H5HF_open(H5F_t *f, hid_t dxpl_id, haddr_t fh_addr)
     HDassert(H5F_addr_defined(fh_addr));
 
     /* Load the heap header into memory */
-    if(NULL == (hdr = H5HF_hdr_protect(f, dxpl_id, fh_addr, H5AC_READ)))
+    if(NULL == (hdr = H5HF_hdr_protect(f, dxpl_id, fh_addr, H5AC__READ_ONLY_FLAG)))
         HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, NULL, "unable to protect fractal heap header")
 
     /* Check for pending heap deletion */
@@ -821,7 +821,7 @@ H5HF_close(H5HF_t *fh, hid_t dxpl_id)
         H5HF_hdr_t *hdr;            /* Another pointer to fractal heap header */
 
         /* Lock the heap header into memory */
-        if(NULL == (hdr = H5HF_hdr_protect(fh->f, dxpl_id, heap_addr, H5AC_WRITE)))
+        if(NULL == (hdr = H5HF_hdr_protect(fh->f, dxpl_id, heap_addr, H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "unable to protect fractal heap header")
 
         /* Delete heap, starting with header (unprotects header) */
@@ -865,7 +865,7 @@ H5HF_delete(H5F_t *f, hid_t dxpl_id, haddr_t fh_addr)
     HDassert(H5F_addr_defined(fh_addr));
 
     /* Lock the heap header into memory */
-    if(NULL == (hdr = H5HF_hdr_protect(f, dxpl_id, fh_addr, H5AC_WRITE)))
+    if(NULL == (hdr = H5HF_hdr_protect(f, dxpl_id, fh_addr, H5AC__NO_FLAGS_SET)))
         HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "unable to protect fractal heap header")
 
     /* Check for files using shared heap header */
diff --git a/src/H5HFcache.c b/src/H5HFcache.c
index 07e5b36..ec8d9a6 100644
--- a/src/H5HFcache.c
+++ b/src/H5HFcache.c
@@ -53,12 +53,6 @@
 #define H5HF_DBLOCK_VERSION     0               /* Direct block */
 #define H5HF_IBLOCK_VERSION     0               /* Indirect block */
 
-/* Size of stack buffer for serialized headers */
-#define H5HF_HDR_BUF_SIZE       512
-
-/* Size of stack buffer for serialized indirect blocks */
-#define H5HF_IBLOCK_BUF_SIZE    4096
-
 
 /******************/
 /* Local Typedefs */
@@ -79,24 +73,48 @@ static herr_t H5HF__dtable_encode(H5F_t *f, uint8_t **pp, const H5HF_dtable_t *d
 static herr_t H5HF__dtable_decode(H5F_t *f, const uint8_t **pp, H5HF_dtable_t *dtable);
 
 /* Metadata cache (H5AC) callbacks */
-static H5HF_hdr_t *H5HF_cache_hdr_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata);
-static herr_t H5HF_cache_hdr_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5HF_hdr_t *hdr, unsigned H5_ATTR_UNUSED * flags_ptr);
-static herr_t H5HF_cache_hdr_dest(H5F_t *f, H5HF_hdr_t *hdr);
-static herr_t H5HF_cache_hdr_clear(H5F_t *f, H5HF_hdr_t *hdr, hbool_t destroy);
-static herr_t H5HF_cache_hdr_size(const H5F_t *f, const H5HF_hdr_t *hdr, size_t *size_ptr);
-static H5HF_indirect_t *H5HF_cache_iblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata);
-static herr_t H5HF_cache_iblock_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5HF_indirect_t *iblock, unsigned H5_ATTR_UNUSED * flags_ptr);
-static herr_t H5HF_cache_iblock_dest(H5F_t *f, H5HF_indirect_t *iblock);
-static herr_t H5HF_cache_iblock_clear(H5F_t *f, H5HF_indirect_t *iblock, hbool_t destroy);
-static herr_t H5HF_cache_iblock_notify(H5C_notify_action_t action, H5HF_indirect_t *iblock);
-static herr_t H5HF_cache_iblock_size(const H5F_t *f, const H5HF_indirect_t *iblock, size_t *size_ptr);
-static H5HF_direct_t *H5HF_cache_dblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata);
-static herr_t H5HF_cache_dblock_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5HF_direct_t *dblock, unsigned H5_ATTR_UNUSED * flags_ptr);
-static herr_t H5HF_cache_dblock_dest(H5F_t *f, H5HF_direct_t *dblock);
-static herr_t H5HF_cache_dblock_clear(H5F_t *f, H5HF_direct_t *dblock, hbool_t destroy);
-static herr_t H5HF_cache_dblock_notify(H5C_notify_action_t action, H5HF_direct_t *dblock);
-static herr_t H5HF_cache_dblock_size(const H5F_t *f, const H5HF_direct_t *dblock, size_t *size_ptr);
-
+static herr_t H5HF__cache_hdr_get_load_size(const void *udata, size_t *image_len);
+static void *H5HF__cache_hdr_deserialize(const void *image, size_t len,
+    void *udata, hbool_t *dirty); 
+static herr_t H5HF__cache_hdr_image_len(const void *thing, size_t *image_len,
+    hbool_t *compressed_ptr, size_t *compressed_image_len_ptr);
+static herr_t H5HF__cache_hdr_pre_serialize(const H5F_t *f, hid_t dxpl_id,
+    void *thing, haddr_t addr, size_t len, size_t compressed_len, 
+    haddr_t *new_addr, size_t *new_len, size_t *new_compressed_len, 
+    unsigned *flags); 
+static herr_t H5HF__cache_hdr_serialize(const H5F_t *f, void *image,
+    size_t len, void *thing); 
+static herr_t H5HF__cache_hdr_free_icr(void *thing);
+
+static herr_t H5HF__cache_iblock_get_load_size(const void *udata, size_t *image_len);
+static void *H5HF__cache_iblock_deserialize(const void *image, size_t len,
+    void *udata, hbool_t *dirty); 
+static herr_t H5HF__cache_iblock_image_len(const void *thing, 
+    size_t *image_len, hbool_t *compressed_ptr, 
+    size_t *compressed_image_len_ptr);
+static herr_t H5HF__cache_iblock_pre_serialize(const H5F_t *f, hid_t dxpl_id,
+    void *thing, haddr_t addr, size_t len, size_t compressed_len, 
+    haddr_t *new_addr, size_t *new_len, size_t *new_compressed_len, 
+    unsigned *flags); 
+static herr_t H5HF__cache_iblock_serialize(const H5F_t *f, void *image,
+    size_t len, void *thing); 
+static herr_t H5HF__cache_iblock_notify(H5C_notify_action_t action, void *thing); 
+static herr_t H5HF__cache_iblock_free_icr(void *thing);
+
+static herr_t H5HF__cache_dblock_get_load_size(const void *udata, size_t *image_len);
+static void *H5HF__cache_dblock_deserialize(const void *image, size_t len,
+    void *udata, hbool_t *dirty); 
+static herr_t H5HF__cache_dblock_image_len(const void *thing, 
+    size_t *image_len, hbool_t *compressed_ptr, 
+    size_t *compressed_image_len_ptr);
+static herr_t H5HF__cache_dblock_pre_serialize(const H5F_t *f, hid_t dxpl_id,
+    void *thing, haddr_t addr, size_t len, size_t compressed_len,
+    haddr_t *new_addr, size_t *new_len, size_t *new_compressed_len, 
+    unsigned *flags); 
+static herr_t H5HF__cache_dblock_serialize(const H5F_t *f, void *image,
+    size_t len, void *thing); 
+static herr_t H5HF__cache_dblock_notify(H5C_notify_action_t action, void *thing);
+static herr_t H5HF__cache_dblock_free_icr(void *thing);
 
 /* Debugging Function Prototypes */
 #ifndef NDEBUG
@@ -117,35 +135,53 @@ static herr_t H5HF__cache_verify_descendant_iblocks_clean(H5F_t *f, hid_t dxpl_i
 
 /* H5HF header inherits cache-like properties from H5AC */
 const H5AC_class_t H5AC_FHEAP_HDR[1] = {{
-    H5AC_FHEAP_HDR_ID,
-    (H5AC_load_func_t)H5HF_cache_hdr_load,
-    (H5AC_flush_func_t)H5HF_cache_hdr_flush,
-    (H5AC_dest_func_t)H5HF_cache_hdr_dest,
-    (H5AC_clear_func_t)H5HF_cache_hdr_clear,
-    (H5AC_notify_func_t)NULL,
-    (H5AC_size_func_t)H5HF_cache_hdr_size,
+    H5AC_FHEAP_HDR_ID,                  /* Metadata client ID */
+    "fractal heap header",              /* Metadata client name (for debugging) */
+    H5FD_MEM_FHEAP_HDR,                 /* File space memory type for client */
+    H5AC__CLASS_SPECULATIVE_LOAD_FLAG,  /* Client class behavior flags */
+    H5HF__cache_hdr_get_load_size,      /* 'get_load_size' callback */
+    H5HF__cache_hdr_deserialize,        /* 'deserialize' callback */
+    H5HF__cache_hdr_image_len,          /* 'image_len' callback */
+    H5HF__cache_hdr_pre_serialize,      /* 'pre_serialize' callback */
+    H5HF__cache_hdr_serialize,          /* 'serialize' callback */
+    NULL,                               /* 'notify' callback */
+    H5HF__cache_hdr_free_icr,           /* 'free_icr' callback */
+    NULL,                               /* 'clear' callback */
+    NULL,                               /* 'fsf_size' callback */
 }};
 
 /* H5HF indirect block inherits cache-like properties from H5AC */
 const H5AC_class_t H5AC_FHEAP_IBLOCK[1] = {{
-    H5AC_FHEAP_IBLOCK_ID,
-    (H5AC_load_func_t)H5HF_cache_iblock_load,
-    (H5AC_flush_func_t)H5HF_cache_iblock_flush,
-    (H5AC_dest_func_t)H5HF_cache_iblock_dest,
-    (H5AC_clear_func_t)H5HF_cache_iblock_clear,
-    (H5AC_notify_func_t)H5HF_cache_iblock_notify,
-    (H5AC_size_func_t)H5HF_cache_iblock_size,
+    H5AC_FHEAP_IBLOCK_ID,               /* Metadata client ID */
+    "fractal heap indirect block",      /* Metadata client name (for debugging) */
+    H5FD_MEM_FHEAP_IBLOCK,              /* File space memory type for client */
+    H5AC__CLASS_NO_FLAGS_SET,           /* Client class behavior flags */
+    H5HF__cache_iblock_get_load_size,   /* 'get_load_size' callback */
+    H5HF__cache_iblock_deserialize,     /* 'deserialize' callback */
+    H5HF__cache_iblock_image_len,       /* 'image_len' callback */
+    H5HF__cache_iblock_pre_serialize,   /* 'pre_serialize' callback */
+    H5HF__cache_iblock_serialize,       /* 'serialize' callback */
+    H5HF__cache_iblock_notify,          /* 'notify' callback */
+    H5HF__cache_iblock_free_icr,        /* 'free_icr' callback */
+    NULL,                               /* 'clear' callback */
+    NULL,                               /* 'fsf_size' callback */
 }};
 
 /* H5HF direct block inherits cache-like properties from H5AC */
 const H5AC_class_t H5AC_FHEAP_DBLOCK[1] = {{
-    H5AC_FHEAP_DBLOCK_ID,
-    (H5AC_load_func_t)H5HF_cache_dblock_load,
-    (H5AC_flush_func_t)H5HF_cache_dblock_flush,
-    (H5AC_dest_func_t)H5HF_cache_dblock_dest,
-    (H5AC_clear_func_t)H5HF_cache_dblock_clear,
-    (H5AC_notify_func_t)H5HF_cache_dblock_notify,
-    (H5AC_size_func_t)H5HF_cache_dblock_size,
+    H5AC_FHEAP_DBLOCK_ID,               /* Metadata client ID */
+    "fractal heap direct block",        /* Metadata client name (for debugging) */
+    H5FD_MEM_FHEAP_DBLOCK,              /* File space memory type for client */
+    H5C__CLASS_COMPRESSED_FLAG,         /* Client class behavior flags */
+    H5HF__cache_dblock_get_load_size,   /* 'get_load_size' callback */
+    H5HF__cache_dblock_deserialize,     /* 'deserialize' callback */
+    H5HF__cache_dblock_image_len,       /* 'image_len' callback */
+    H5HF__cache_dblock_pre_serialize,   /* 'pre_serialize' callback */
+    H5HF__cache_dblock_serialize,       /* 'serialize' callback */
+    H5HF__cache_dblock_notify,          /* 'notify' callback */
+    H5HF__cache_dblock_free_icr,        /* 'free_icr' callback */
+    NULL,                               /* 'clear' callback */
+    NULL,                               /* 'fsf_size' callback */
 }};
 
 
@@ -268,119 +304,191 @@ H5HF__dtable_encode(H5F_t *f, uint8_t **pp, const H5HF_dtable_t *dtable)
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HF_cache_hdr_load
+ * Function:	H5HF__cache_hdr_get_load_size()
  *
- * Purpose:	Loads a fractal heap header from the disk.
+ * Purpose:	Determine the size of the fractal heap header on disk,
+ *		and set *image_len to this value.
  *
- * Return:	Success:	Pointer to a new fractal heap
+ *		This code is based on the old H5HF_cache_hdr_load() routine
+ *		that was used with the version 2 metadata cache.  Note the 
+ *		use of a dummy header to compute the on disk size of the header.
+ *
+ *		Note also that the value returned by this function presumes that 
+ *		there is no I/O filtering data in the header.  If there is, the 
+ *		size reported will be too small, and H5C_load_entry()
+ *		will have to make two tries to load the fractal heap header.
+ *
+ * Return:	Success:	SUCCEED
+ *		Failure:	FAIL
+ *
+ * Programmer:	John Mainzer
+ *		6/21/14
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t 
+H5HF__cache_hdr_get_load_size(const void *_udata, size_t *image_len)
+{
+    const H5HF_hdr_cache_ud_t *udata = (const H5HF_hdr_cache_ud_t *)_udata; /* pointer to user data */
+    H5HF_hdr_t  	dummy_hdr; 	/* dummy header -- to compute size */
+
+    FUNC_ENTER_STATIC_NOERR
+
+    /* Sanity checks */
+    HDassert(udata);
+    HDassert(image_len);
+
+    /* Set the internal parameters for the heap */
+    dummy_hdr.f = udata->f;
+    dummy_hdr.sizeof_size = H5F_SIZEOF_SIZE(udata->f);
+    dummy_hdr.sizeof_addr = H5F_SIZEOF_ADDR(udata->f);
+
+    /* Compute the 'base' size of the fractal heap header on disk */
+    *image_len = (size_t)H5HF_HEADER_SIZE(&dummy_hdr);
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5HF__cache_hdr_get_load_size() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF__cache_hdr_deserialize
+ *
+ * Purpose:	Given a buffer containing an on disk image of a fractal heap
+ *		header block, allocate an instance of H5HF_hdr_t, load the contents
+ *		of the buffer into into the new instance of H5HF_hdr_t, and then
+ *		return a pointer to the new instance.
+ *
+ *		Since H5HF__cache_hdr_get_load_size() reports header on disk size 
+ *		base on the assumption that the header contains no I/O filtering 
+ *		data, it is possible that the provided image will be too small.
+ *
+ *		In this case, we DO NOT flag an error when this is discovered.
+ *		Instead, we make note of the correct image size, and report 
+ *		success.
+ *
+ *		Since H5HF__cache_hdr_image_len() callback is defined, 
+ *		H5C_load_entry() will call H5HF__cache_hdr_image_len() and 
+ *		obtain the correct image length.  
+ *
+ *		Since the H5AC__CLASS_SPECULATIVE_LOAD_FLAG is set, 
+ *		H5C_load_entry() will load an image of the correct size, and 
+ *		then call this function again to deserialize it.  Before doing 
+ *		so, it will also call H5HF__cache_hdr_free_icr() to discard the 
+ *		result of the first deserialize call.
+ *
+ *		Note that the v2 B-tree and free space manager associated 
+ *		with the fractal heap (roots stored in the huge_bt2 and fspace 
+ *		fields respectively) are not loaded at this time.  As best I can
+ *		tell from reviewing the code, they are loaded or created when 
+ *		they are accessed.
+ *
+ * Return:	Success:	Pointer to in core representation
  *		Failure:	NULL
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Feb 24 2006
+ * Programmer:	John Mainzer
+ *		6/21/14
  *
  *-------------------------------------------------------------------------
  */
-static H5HF_hdr_t *
-H5HF_cache_hdr_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
+static void *
+H5HF__cache_hdr_deserialize(const void *_image, size_t len, void *_udata,
+    hbool_t H5_ATTR_UNUSED *dirty)
 {
-    H5HF_hdr_t		*hdr = NULL;     /* Fractal heap info */
-    H5HF_hdr_cache_ud_t *udata = (H5HF_hdr_cache_ud_t *)_udata;
-    size_t		size;           /* Header size */
-    H5WB_t              *wb = NULL;     /* Wrapped buffer for header data */
-    uint8_t             hdr_buf[H5HF_HDR_BUF_SIZE]; /* Buffer for header */
-    uint8_t		*buf;           /* Pointer to header buffer */
-    const uint8_t	*p;             /* Pointer into raw data buffer */
+    H5HF_hdr_t          *hdr = NULL;     /* Fractal heap info */
+    H5HF_hdr_cache_ud_t *udata = (H5HF_hdr_cache_ud_t *)_udata; /* User data for callback */
+    const uint8_t       *image = (const uint8_t *)_image;       /* Pointer into into supplied image */
+    size_t              size;           /* Header size */
     uint32_t            stored_chksum;  /* Stored metadata checksum value */
     uint32_t            computed_chksum; /* Computed metadata checksum value */
     uint8_t             heap_flags;     /* Status flags for heap */
-    H5HF_hdr_t		*ret_value;     /* Return value */
+    void *              ret_value;      /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
-    /* Check arguments */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
+    /* Sanity checks */
+    HDassert(image);
+    HDassert(len > 0);
     HDassert(udata);
+    HDassert(dirty);
 
     /* Allocate space for the fractal heap data structure */
     if(NULL == (hdr = H5HF_hdr_alloc(udata->f)))
         HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed")
 
-    /* Wrap the local buffer for serialized header info */
-    if(NULL == (wb = H5WB_wrap(hdr_buf, sizeof(hdr_buf))))
-        HGOTO_ERROR(H5E_HEAP, H5E_CANTINIT, NULL, "can't wrap buffer")
-
     /* Compute the 'base' size of the fractal heap header on disk */
     size = (size_t)H5HF_HEADER_SIZE(hdr);
 
-    /* Get a pointer to a buffer that's large enough for serialized header */
-    if(NULL == (buf = (uint8_t *)H5WB_actual(wb, size)))
-        HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, NULL, "can't get actual buffer")
-
-    /* Read header from disk */
-    if(H5F_block_read(f, H5FD_MEM_FHEAP_HDR, addr, size, dxpl_id, buf) < 0)
-	HGOTO_ERROR(H5E_HEAP, H5E_READERROR, NULL, "can't read fractal heap header")
-
-    /* Get temporary pointer to serialized header */
-    p = buf;
+    /* the size we have just calculated presumes that there is no I/O 
+     * filter information in the header.  If there is no filter information,
+     * the deserialize operation should succeed.
+     *
+     * If there is filter information, the first attempt to deserialize 
+     * the header will reveal this.  In this case, we will be unable to 
+     * deserialize the header as the supplied image will be too small.
+     * However, we will make note of the correct size and report success 
+     * anyway.  
+     *
+     * When H5C_load_entry() calls H5HF__cache_hdr_image_len(), we will report 
+     * the correct size.  Since the H5C__CLASS_SPECULATIVE_LOAD_FLAG is set,
+     * this will prompt H5C_load_entry() to load the correct size image,
+     * discard the result of the first attempt at deserialization, and 
+     * call this routine a second time to deserialize the correct size 
+     * buffer.
+     */
+    HDassert(size <= len);
 
     /* Magic number */
-    if(HDmemcmp(p, H5HF_HDR_MAGIC, (size_t)H5_SIZEOF_MAGIC))
-        HGOTO_ERROR(H5E_HEAP, H5E_CANTLOAD, NULL, "wrong fractal heap header signature")
-    p += H5_SIZEOF_MAGIC;
+    if(HDmemcmp(image, H5HF_HDR_MAGIC, (size_t)H5_SIZEOF_MAGIC))
+        HGOTO_ERROR(H5E_HEAP, H5E_BADVALUE, NULL, "wrong fractal heap header signature")
+    image += H5_SIZEOF_MAGIC;
 
     /* Version */
-    if(*p++ != H5HF_HDR_VERSION)
+    if(*image++ != H5HF_HDR_VERSION)
         HGOTO_ERROR(H5E_HEAP, H5E_VERSION, NULL, "wrong fractal heap header version")
 
     /* General heap information */
-    UINT16DECODE(p, hdr->id_len);               /* Heap ID length */
-    UINT16DECODE(p, hdr->filter_len);           /* I/O filters' encoded length */
+    UINT16DECODE(image, hdr->id_len);              /* Heap ID length */
+    UINT16DECODE(image, hdr->filter_len);          /* I/O filters' encoded length */
 
     /* Heap status flags */
     /* (bit 0: "huge" object IDs have wrapped) */
     /* (bit 1: checksum direct blocks) */
-    heap_flags = *p++;
+    heap_flags = *image++;
     hdr->huge_ids_wrapped = heap_flags & H5HF_HDR_FLAGS_HUGE_ID_WRAPPED;
     hdr->checksum_dblocks = heap_flags & H5HF_HDR_FLAGS_CHECKSUM_DBLOCKS;
 
     /* "Huge" object information */
-    UINT32DECODE(p, hdr->max_man_size);         /* Max. size of "managed" objects */
-    H5F_DECODE_LENGTH(udata->f, p, hdr->huge_next_id); /* Next ID to use for "huge" object */
-    H5F_addr_decode(udata->f, &p, &hdr->huge_bt2_addr); /* Address of "huge" object tracker B-tree */
+    UINT32DECODE(image, hdr->max_man_size);     /* Max. size of "managed" objects */
+    H5F_DECODE_LENGTH(udata->f, image, hdr->huge_next_id); /* Next ID to use for "huge" object */
+    H5F_addr_decode(udata->f, &image, &hdr->huge_bt2_addr); /* Address of "huge" object tracker B-tree */
 
     /* "Managed" object free space information */
-    H5F_DECODE_LENGTH(udata->f, p, hdr->total_man_free); /* Internal free space in managed direct blocks */
-    H5F_addr_decode(udata->f, &p, &hdr->fs_addr);      /* Address of free section header */
+    H5F_DECODE_LENGTH(udata->f, image, hdr->total_man_free); /* Internal free space in managed direct blocks */
+    H5F_addr_decode(udata->f, &image, &hdr->fs_addr);  /* Address of free section header */
 
     /* Heap statistics */
-    H5F_DECODE_LENGTH(udata->f, p, hdr->man_size);
-    H5F_DECODE_LENGTH(udata->f, p, hdr->man_alloc_size);
-    H5F_DECODE_LENGTH(udata->f, p, hdr->man_iter_off);
-    H5F_DECODE_LENGTH(udata->f, p, hdr->man_nobjs);
-    H5F_DECODE_LENGTH(udata->f, p, hdr->huge_size);
-    H5F_DECODE_LENGTH(udata->f, p, hdr->huge_nobjs);
-    H5F_DECODE_LENGTH(udata->f, p, hdr->tiny_size);
-    H5F_DECODE_LENGTH(udata->f, p, hdr->tiny_nobjs);
+    H5F_DECODE_LENGTH(udata->f, image, hdr->man_size);
+    H5F_DECODE_LENGTH(udata->f, image, hdr->man_alloc_size);
+    H5F_DECODE_LENGTH(udata->f, image, hdr->man_iter_off);
+    H5F_DECODE_LENGTH(udata->f, image, hdr->man_nobjs);
+    H5F_DECODE_LENGTH(udata->f, image, hdr->huge_size);
+    H5F_DECODE_LENGTH(udata->f, image, hdr->huge_nobjs);
+    H5F_DECODE_LENGTH(udata->f, image, hdr->tiny_size);
+    H5F_DECODE_LENGTH(udata->f, image, hdr->tiny_nobjs);
 
     /* Managed objects' doubling-table info */
-    if(H5HF__dtable_decode(hdr->f, &p, &(hdr->man_dtable)) < 0)
+    if(H5HF__dtable_decode(hdr->f, &image, &(hdr->man_dtable)) < 0)
         HGOTO_ERROR(H5E_HEAP, H5E_CANTENCODE, NULL, "unable to encode managed obj. doubling table info")
 
     /* Sanity check */
     /* (allow for checksum not decoded yet) */
-    HDassert((size_t)(p - (const uint8_t *)buf) == (size - H5HF_SIZEOF_CHKSUM));
+    HDassert((size_t)(image - (const uint8_t *)_image) == (size - H5HF_SIZEOF_CHKSUM));
 
     /* Check for I/O filter information to decode */
     if(hdr->filter_len > 0) {
-        size_t filter_info_off;     /* Offset in header of filter information */
         size_t filter_info_size;    /* Size of filter information */
         H5O_pline_t *pline;         /* Pipeline information from the header on disk */
 
-        /* Compute the offset of the filter info in the header */
-        filter_info_off = (size_t)(p - (const uint8_t *)buf);
-
         /* Compute the size of the extra filter information */
         filter_info_size = (size_t)(hdr->sizeof_size     /* Size of size for filtered root direct block */
             + (unsigned)4		/* Size of filter mask for filtered root direct block */
@@ -389,28 +497,27 @@ H5HF_cache_hdr_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
         /* Compute the heap header's size */
         hdr->heap_size = size + filter_info_size;
 
-        /* Re-size current buffer */
-        if(NULL == (buf = (uint8_t *)H5WB_actual(wb, hdr->heap_size)))
-            HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, NULL, "can't get actual buffer")
-
-        /* Read in I/O filter information */
-        /* (and the checksum) */
-        if(H5F_block_read(f, H5FD_MEM_FHEAP_HDR, (addr + filter_info_off), (filter_info_size + H5HF_SIZEOF_CHKSUM), dxpl_id, (buf + filter_info_off)) < 0)
-            HGOTO_ERROR(H5E_HEAP, H5E_READERROR, NULL, "can't read fractal heap header's I/O pipeline filter info")
+        if(size == len) 
+	    /* we were supplied with too small a buffer -- goto done
+             * and let H5C_load_entry() retry with a larger buffer
+             */
+	    HGOTO_DONE((void *)hdr)
 
-        /* Point at correct offset in header for the filter information */
-        p = buf + filter_info_off;
+	else
+            if((size + filter_info_size) != len)
+                HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, NULL, "bad image len")
 
         /* Decode the size of a filtered root direct block */
-        H5F_DECODE_LENGTH(udata->f, p, hdr->pline_root_direct_size);
+        H5F_DECODE_LENGTH(udata->f, image, hdr->pline_root_direct_size);
 
         /* Decode the filter mask for a filtered root direct block */
-        UINT32DECODE(p, hdr->pline_root_direct_filter_mask);
+        UINT32DECODE(image, hdr->pline_root_direct_filter_mask);
 
         /* Decode I/O filter information */
-        if(NULL == (pline = (H5O_pline_t *)H5O_msg_decode(hdr->f, udata->dxpl_id, NULL, H5O_PLINE_ID, p)))
+        if(NULL == (pline = (H5O_pline_t *)H5O_msg_decode(hdr->f, udata->dxpl_id, NULL, H5O_PLINE_ID, image)))
             HGOTO_ERROR(H5E_HEAP, H5E_CANTDECODE, NULL, "can't decode I/O pipeline filters")
-        p += hdr->filter_len;
+
+        image += hdr->filter_len;
 
         /* Copy the information into the header's I/O pipeline structure */
         if(NULL == H5O_msg_copy(H5O_PLINE_ID, pline, &(hdr->pline)))
@@ -425,13 +532,13 @@ H5HF_cache_hdr_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
 
     /* Compute checksum on entire header */
     /* (including the filter information, if present) */
-    computed_chksum = H5_checksum_metadata(buf, (size_t)(p - (const uint8_t *)buf), 0);
+    computed_chksum = H5_checksum_metadata(_image, (size_t)(image - (const uint8_t *)_image), 0);
 
     /* Metadata checksum */
-    UINT32DECODE(p, stored_chksum);
+    UINT32DECODE(image, stored_chksum);
 
     /* Sanity check */
-    HDassert((size_t)(p - (const uint8_t *)buf) == hdr->heap_size);
+    HDassert((size_t)(image - (const uint8_t *)_image) == hdr->heap_size);
 
     /* Verify checksum */
     if(stored_chksum != computed_chksum)
@@ -442,291 +549,324 @@ H5HF_cache_hdr_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
         HGOTO_ERROR(H5E_RESOURCE, H5E_CANTINIT, NULL, "can't finish initializing shared fractal heap header")
 
     /* Set return value */
-    ret_value = hdr;
+    ret_value = (void *)hdr;
 
 done:
-    /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-        HDONE_ERROR(H5E_HEAP, H5E_CLOSEERROR, NULL, "can't close wrapped buffer")
     if(!ret_value && hdr)
         if(H5HF_hdr_free(hdr) < 0)
             HDONE_ERROR(H5E_HEAP, H5E_CANTRELEASE, NULL, "unable to release fractal heap header")
 
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5HF_cache_hdr_load() */ /*lint !e818 Can't make udata a pointer to const */
+} /* end H5HF__cache_hdr_deserialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HF_cache_hdr_flush
+ * Function:	H5HF__cache_hdr_image_len
  *
- * Purpose:	Flushes a dirty fractal heap header to disk.
+ * Purpose:	Return the actual size of the fractal heap header on 
+ *		disk image.  
  *
- * Return:	Non-negative on success/Negative on failure
+ *		If the header contains filter information, this size will be 
+ *		larger than the value returned by H5HF__cache_hdr_get_load_size().  
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Feb 24 2006
+ * Return:	Success:	SUCCEED
+ *		Failure:	FAIL
+ *
+ * Programmer:	John Mainzer
+ *		6/21/14
  *
  *-------------------------------------------------------------------------
  */
-static herr_t
-H5HF_cache_hdr_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5HF_hdr_t *hdr, unsigned H5_ATTR_UNUSED * flags_ptr)
+static herr_t 
+H5HF__cache_hdr_image_len(const void *_thing, size_t *image_len,
+    hbool_t H5_ATTR_UNUSED *compressed_ptr, size_t H5_ATTR_UNUSED *compressed_image_len_ptr)
 {
-    H5WB_t *wb = NULL;                  /* Wrapped buffer for header data */
-    uint8_t hdr_buf[H5HF_HDR_BUF_SIZE]; /* Buffer for header */
-    herr_t ret_value = SUCCEED;         /* Return value */
+    const H5HF_hdr_t  *hdr = (const H5HF_hdr_t *)_thing;    /* Fractal heap info */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC_NOERR
 
-    /* check arguments */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
+    /* Sanity checks */
     HDassert(hdr);
+    HDassert(hdr->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(hdr->cache_info.type == H5AC_FHEAP_HDR);
+    HDassert(image_len);
 
-    if(hdr->cache_info.is_dirty) {
-        uint8_t	*buf;           /* Temporary raw data buffer */
-        uint8_t *p;             /* Pointer into raw data buffer */
-        size_t	size;           /* Header size on disk */
-        uint8_t heap_flags;     /* Status flags for heap */
-        uint32_t metadata_chksum; /* Computed metadata checksum value */
-
-#ifndef NDEBUG
-{
-        /* Verify that flush dependencies are working correctly.  Do this
-	 * by verifying that either:
-         *
-         * 1) the header has a root iblock, and that the root iblock and all
- 	 *    of its children are clean, or
-         *
-         * 2) The header has a root dblock, which is clean, or
-         *
-         * 3) The heap is empty, and thus the header has neither a root
-         *    iblock no a root dblock.  In this case, the flush ordering
-         *    constraint is met by default.
-	 *
- 	 * Do this with a call to H5HF__cache_verify_hdr_descendants_clean().
-	 */
-	hbool_t descendants_clean = TRUE;
+    *image_len = hdr->heap_size;
 
-	if(H5HF__cache_verify_hdr_descendants_clean(f, dxpl_id, hdr, &descendants_clean) < 0)
-	     HGOTO_ERROR(H5E_HEAP, H5E_SYSTEM, FAIL, "can't verify hdr descendants clean.")
-	HDassert(descendants_clean);
-}
-#endif /* NDEBUG */
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5HF__cache_hdr_image_len() */
 
-        /* Set the shared heap header's file context for this operation */
-        hdr->f = f;
-
-        /* Wrap the local buffer for serialized header info */
-        if(NULL == (wb = H5WB_wrap(hdr_buf, sizeof(hdr_buf))))
-            HGOTO_ERROR(H5E_HEAP, H5E_CANTINIT, FAIL, "can't wrap buffer")
-
-        /* Compute the size of the heap header on disk */
-        size = hdr->heap_size;
-
-        /* Get a pointer to a buffer that's large enough for serialized header */
-        if(NULL == (buf = (uint8_t *)H5WB_actual(wb, size)))
-            HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, FAIL, "can't get actual buffer")
-
-        /* Get temporary pointer to serialized header */
-        p = buf;
-
-        /* Magic number */
-        HDmemcpy(p, H5HF_HDR_MAGIC, (size_t)H5_SIZEOF_MAGIC);
-        p += H5_SIZEOF_MAGIC;
-
-        /* Version # */
-        *p++ = H5HF_HDR_VERSION;
-
-        /* General heap information */
-        UINT16ENCODE(p, hdr->id_len);           /* Heap ID length */
-        UINT16ENCODE(p, hdr->filter_len);       /* I/O filters' encoded length */
-
-        /* Heap status flags */
-        /* (bit 0: "huge" object IDs have wrapped) */
-        /* (bit 1: checksum direct blocks) */
-        heap_flags = 0;
-        heap_flags = (uint8_t)(heap_flags | (hdr->huge_ids_wrapped ? H5HF_HDR_FLAGS_HUGE_ID_WRAPPED : 0));
-        heap_flags = (uint8_t)(heap_flags | (hdr->checksum_dblocks ? H5HF_HDR_FLAGS_CHECKSUM_DBLOCKS : 0));
-        *p++ = heap_flags;
-
-        /* "Huge" object information */
-        UINT32ENCODE(p, hdr->max_man_size);             /* Max. size of "managed" objects */
-        H5F_ENCODE_LENGTH(f, p, hdr->huge_next_id);     /* Next ID to use for "huge" object */
-        H5F_addr_encode(f, &p, hdr->huge_bt2_addr);     /* Address of "huge" object tracker B-tree */
-
-        /* "Managed" object free space information */
-        H5F_ENCODE_LENGTH(f, p, hdr->total_man_free);   /* Internal free space in managed direct blocks */
-        H5F_addr_encode(f, &p, hdr->fs_addr);           /* Address of free section header */
-
-        /* Heap statistics */
-        H5F_ENCODE_LENGTH(f, p, hdr->man_size);
-        H5F_ENCODE_LENGTH(f, p, hdr->man_alloc_size);
-        H5F_ENCODE_LENGTH(f, p, hdr->man_iter_off);
-        H5F_ENCODE_LENGTH(f, p, hdr->man_nobjs);
-        H5F_ENCODE_LENGTH(f, p, hdr->huge_size);
-        H5F_ENCODE_LENGTH(f, p, hdr->huge_nobjs);
-        H5F_ENCODE_LENGTH(f, p, hdr->tiny_size);
-        H5F_ENCODE_LENGTH(f, p, hdr->tiny_nobjs);
-
-        /* Managed objects' doubling-table info */
-        if(H5HF__dtable_encode(hdr->f, &p, &(hdr->man_dtable)) < 0)
-	    HGOTO_ERROR(H5E_HEAP, H5E_CANTENCODE, FAIL, "unable to encode managed obj. doubling table info")
-
-        /* Check for I/O filter information to encode */
-        if(hdr->filter_len > 0) {
-            /* Encode the size of a filtered root direct block */
-            H5F_ENCODE_LENGTH(f, p, hdr->pline_root_direct_size);
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF__cache_hdr_pre_serialize
+ *
+ * Purpose:	As best I can tell, fractal heap header blocks are always 
+ *		allocated in real file space.  Thus this routine simply verifies
+ *		this, verifies that the len parameter contains the expected
+ *		value, and returns an error if either of these checks fail.
+ *
+ *		When compiled in debug mode, the function also verifies that all
+ *		indirect and direct blocks that are children of the header are 
+ *		either clean, or not in the metadata cache.
+ *
+ * Return:	Success:	SUCCEED
+ *		Failure:	FAIL
+ *
+ * Programmer:	John Mainzer
+ *		6/21/14
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t 
+H5HF__cache_hdr_pre_serialize(const H5F_t *f, hid_t dxpl_id, void *_thing,
+    haddr_t addr, size_t len, size_t H5_ATTR_UNUSED compressed_len, 
+    haddr_t H5_ATTR_UNUSED *new_addr, size_t H5_ATTR_UNUSED *new_len,
+    size_t H5_ATTR_UNUSED *new_compressed_len, unsigned *flags)
+{
+    H5HF_hdr_t *hdr = (H5HF_hdr_t *)_thing;     /* Fractal heap info */
+    herr_t      ret_value = SUCCEED;    /* Return value */
 
-            /* Encode the filter mask for a filtered root direct block */
-            UINT32ENCODE(p, hdr->pline_root_direct_filter_mask);
+    FUNC_ENTER_STATIC
 
-            /* Encode I/O filter information */
-            if(H5O_msg_encode(hdr->f, H5O_PLINE_ID, FALSE, p, &(hdr->pline)) < 0)
-                HGOTO_ERROR(H5E_HEAP, H5E_CANTENCODE, FAIL, "can't encode I/O pipeline fiters")
-            p += hdr->filter_len;
-        } /* end if */
+    /* Sanity checks */
+    HDassert(f);
+    HDassert(hdr);
+    HDassert(hdr->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(hdr->cache_info.type == H5AC_FHEAP_HDR);
+    HDassert(H5F_addr_defined(addr));
+    HDassert(addr == hdr->heap_addr);
+    HDassert(new_addr);
+    HDassert(new_len);
+    HDassert(flags);
 
-        /* Compute metadata checksum */
-        metadata_chksum = H5_checksum_metadata(buf, (size_t)(p - buf), 0);
+#ifndef NDEBUG
+{
+    hbool_t descendants_clean = TRUE;
 
-        /* Metadata checksum */
-        UINT32ENCODE(p, metadata_chksum);
+    /* Verify that flush dependencies are working correctly.  Do this
+     * by verifying that either:
+     *
+     * 1) the header has a root iblock, and that the root iblock and all
+     *    of its children are clean, or
+     *
+     * 2) The header has a root dblock, which is clean, or
+     *
+     * 3) The heap is empty, and thus the header has neither a root
+     *    iblock no a root dblock.  In this case, the flush ordering
+     *    constraint is met by default.
+     *
+     * Do this with a call to H5HF__cache_verify_hdr_descendants_clean().
+     */
+    if(H5HF__cache_verify_hdr_descendants_clean((H5F_t *)f, dxpl_id, hdr, &descendants_clean) < 0)
+         HGOTO_ERROR(H5E_HEAP, H5E_SYSTEM, FAIL, "can't verify hdr descendants clean.")
+    HDassert(descendants_clean);
+}
+#endif /* NDEBUG */
 
-	/* Write the heap header. */
-        HDassert((size_t)(p - buf) == size);
-	if(H5F_block_write(f, H5FD_MEM_FHEAP_HDR, addr, size, dxpl_id, buf) < 0)
-	    HGOTO_ERROR(H5E_HEAP, H5E_CANTFLUSH, FAIL, "unable to save fractal heap header to disk")
+    if(H5F_IS_TMP_ADDR(f, addr))
+        HGOTO_ERROR(H5E_HEAP, H5E_BADVALUE, FAIL, "addr in temporary space?!?.");
 
-	hdr->cache_info.is_dirty = FALSE;
-    } /* end if */
+    if(len != hdr->heap_size)
+        HGOTO_ERROR(H5E_HEAP, H5E_BADVALUE, FAIL, "unexpected image len.");
 
-    if(destroy)
-        if(H5HF_cache_hdr_dest(f, hdr) < 0)
-	    HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to destroy fractal heap header")
+    *flags = 0;
 
 done:
-    /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-        HDONE_ERROR(H5E_HEAP, H5E_CLOSEERROR, FAIL, "can't close wrapped buffer")
-
     FUNC_LEAVE_NOAPI(ret_value)
-} /* H5HF_cache_hdr_flush() */
+} /* end H5HF__cache_hdr_pre_serialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HF_cache_hdr_dest
+ * Function:	H5HF__cache_hdr_serialize
  *
- * Purpose:	Destroys a fractal heap header in memory.
+ * Purpose:	Construct the on disk image of the header, and place it in 
+ *		the buffer pointed to by image.  Return SUCCEED on success,
+ *		and FAIL on failure.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:	Success:	SUCCEED
+ *		Failure:	FAIL
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Feb 24 2006
+ * Programmer:	John Mainzer
+ *		6/21/14
  *
  *-------------------------------------------------------------------------
  */
-static herr_t
-H5HF_cache_hdr_dest(H5F_t *f, H5HF_hdr_t *hdr)
+static herr_t 
+H5HF__cache_hdr_serialize(const H5F_t *f, void *_image, size_t len,
+    void *_thing)
 {
+    H5HF_hdr_t *hdr = (H5HF_hdr_t *)_thing;     /* Fractal heap info */
+    uint8_t    *image = (uint8_t *)_image;      /* Pointer into raw data buffer */
+    uint8_t 	heap_flags;             /* Status flags for heap */
+    uint32_t 	metadata_chksum;        /* Computed metadata checksum value */
     herr_t      ret_value = SUCCEED;    /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
-    /*
-     * Check arguments.
-     */
+    /* Sanity checks */
+    HDassert(f);
+    HDassert(image);
     HDassert(hdr);
-    HDassert(hdr->rc == 0);
+    HDassert(hdr->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(hdr->cache_info.type == H5AC_FHEAP_HDR);
+    HDassert(len == hdr->heap_size);
 
-    /* If we're going to free the space on disk, the address must be valid */
-    HDassert(!hdr->cache_info.free_file_space_on_destroy || H5F_addr_defined(hdr->cache_info.addr));
+    /* Set the shared heap header's file context for this operation */
+    hdr->f = f;
+
+    /* Magic number */
+    HDmemcpy(image, H5HF_HDR_MAGIC, (size_t)H5_SIZEOF_MAGIC);
+    image += H5_SIZEOF_MAGIC;
 
-    /* Check for freeing file space for heap header */
-    if(hdr->cache_info.free_file_space_on_destroy) {
-        /* Release the space on disk */
-        /* (XXX: Nasty usage of internal DXPL value! -QAK) */
-        if(H5MF_xfree(f, H5FD_MEM_FHEAP_HDR, H5AC_dxpl_id, hdr->cache_info.addr, (hsize_t)hdr->heap_size) < 0)
-            HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to free fractal heap header")
+    /* Version # */
+    *image++ = H5HF_HDR_VERSION;
+
+    /* General heap information */
+    UINT16ENCODE(image, hdr->id_len);           /* Heap ID length */
+    UINT16ENCODE(image, hdr->filter_len);       /* I/O filters' encoded length */
+
+    /* Heap status flags */
+    /* (bit 0: "huge" object IDs have wrapped) */
+    /* (bit 1: checksum direct blocks) */
+    heap_flags = 0;
+    heap_flags = (uint8_t)(heap_flags | (hdr->huge_ids_wrapped ? H5HF_HDR_FLAGS_HUGE_ID_WRAPPED : 0));
+    heap_flags = (uint8_t)(heap_flags | (hdr->checksum_dblocks ? H5HF_HDR_FLAGS_CHECKSUM_DBLOCKS : 0));
+    *image++ = heap_flags;
+
+    /* "Huge" object information */
+    UINT32ENCODE(image, hdr->max_man_size);   /* Max. size of "managed" objects */
+    H5F_ENCODE_LENGTH(f, image, hdr->huge_next_id); /* Next ID to use for "huge" object */
+    H5F_addr_encode(f, &image, hdr->huge_bt2_addr); /* Address of "huge" object tracker B-tree */
+
+    /* "Managed" object free space information */
+    H5F_ENCODE_LENGTH(f, image, hdr->total_man_free); /* Internal free space in managed direct blocks */
+    H5F_addr_encode(f, &image, hdr->fs_addr); /* Address of free section header */
+
+    /* Heap statistics */
+    H5F_ENCODE_LENGTH(f, image, hdr->man_size);
+    H5F_ENCODE_LENGTH(f, image, hdr->man_alloc_size);
+    H5F_ENCODE_LENGTH(f, image, hdr->man_iter_off);
+    H5F_ENCODE_LENGTH(f, image, hdr->man_nobjs);
+    H5F_ENCODE_LENGTH(f, image, hdr->huge_size);
+    H5F_ENCODE_LENGTH(f, image, hdr->huge_nobjs);
+    H5F_ENCODE_LENGTH(f, image, hdr->tiny_size);
+    H5F_ENCODE_LENGTH(f, image, hdr->tiny_nobjs);
+
+    /* Managed objects' doubling-table info */
+    if(H5HF__dtable_encode(hdr->f, &image, &(hdr->man_dtable)) < 0)
+        HGOTO_ERROR(H5E_HEAP, H5E_CANTENCODE, FAIL, "unable to encode managed obj. doubling table info")
+
+    /* Check for I/O filter information to encode */
+    if(hdr->filter_len > 0) {
+        /* Encode the size of a filtered root direct block */
+        H5F_ENCODE_LENGTH(f, image, hdr->pline_root_direct_size);
+
+        /* Encode the filter mask for a filtered root direct block */
+        UINT32ENCODE(image, hdr->pline_root_direct_filter_mask);
+
+        /* Encode I/O filter information */
+        if(H5O_msg_encode(hdr->f, H5O_PLINE_ID, FALSE, image, &(hdr->pline)) < 0)
+            HGOTO_ERROR(H5E_HEAP, H5E_CANTENCODE, FAIL, "can't encode I/O pipeline fiters")
+        image += hdr->filter_len;
     } /* end if */
 
-    /* Free the shared info itself */
-    if(H5HF_hdr_free(hdr) < 0)
-        HGOTO_ERROR(H5E_HEAP, H5E_CANTRELEASE, FAIL, "unable to release fractal heap header")
+    /* Compute metadata checksum */
+    metadata_chksum = H5_checksum_metadata(_image, (size_t)(image - (uint8_t *)_image), 0);
+
+    /* Metadata checksum */
+    UINT32ENCODE(image, metadata_chksum);
+
+    /* sanity check */
+    HDassert((size_t)(image - (uint8_t *)_image) == len);
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5HF_cache_hdr_dest() */
+} /* end H5HF__cache_hdr_serialize() */
+
+/***************************************/
+/* no H5HF__cache_hdr_notify() function */
+/***************************************/
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HF_cache_hdr_clear
+ * Function:	H5HF__cache_hdr_free_icr
  *
- * Purpose:	Mark a fractal heap header in memory as non-dirty.
+ * Purpose:	Free the in core representation of the fractal heap header.
  *
- * Return:	Non-negative on success/Negative on failure
+ *		This routine frees just the header itself, not the 
+ *		associated version 2 B-Tree, the associated Free Space Manager,
+ *		nor the indirect/direct block tree that is rooted in the header.
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Feb 24 2006
+ *		This routine also does not free the file space that may
+ *		be allocated to the header.
+ *
+ * Note:	The metadata cache sets the object's cache_info.magic to
+ *		H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC before calling a free_icr
+ *		callback (checked in assert).
+ *
+ * Return:	Success:	SUCCEED
+ *		Failure:	FAIL
+ *
+ * Programmer:	John Mainzer
+ *		6/21/14
  *
  *-------------------------------------------------------------------------
  */
-static herr_t
-H5HF_cache_hdr_clear(H5F_t *f, H5HF_hdr_t *hdr, hbool_t destroy)
+static herr_t 
+H5HF__cache_hdr_free_icr(void *_thing)
 {
-    herr_t ret_value = SUCCEED;         /* Return value */
+    H5HF_hdr_t *hdr = (H5HF_hdr_t *)_thing;     /* Fractal heap info */
+    herr_t      ret_value = SUCCEED;            /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
-    /*
-     * Check arguments.
-     */
+    /* Sanity checks */
     HDassert(hdr);
+    HDassert(hdr->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC);
+    HDassert(hdr->cache_info.type == H5AC_FHEAP_HDR);
+    HDassert(hdr->rc == 0);
 
-    /* Reset the dirty flag.  */
-    hdr->cache_info.is_dirty = FALSE;
-
-    if(destroy)
-        if(H5HF_cache_hdr_dest(f, hdr) < 0)
-	    HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to destroy fractal heap header")
+    if(H5HF_hdr_free(hdr) < 0)
+        HGOTO_ERROR(H5E_HEAP, H5E_CANTRELEASE, FAIL, "unable to release fractal heap header")
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5HF_cache_hdr_clear() */
+} /* end H5HF__cache_hdr_free_icr() */
+
+/***********************************************************/
+/* metadata cache callback definitions for indirect blocks */
+/***********************************************************/
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HF_cache_hdr_size
+ * Function:	H5HF__cache_iblock_get_load_size()
  *
- * Purpose:	Compute the size in bytes of a fractal heap header
- *		on disk, and return it in *size_ptr.  On failure,
- *		the value of *size_ptr is undefined.
+ * Purpose:	Compute the size of the on disk image of the indirect 
+ *		block, and place this value in *image_len.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:	Success:	SUCCEED
+ *		Failure:	FAIL
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Feb 24 2006
+ * Programmer:	John Mainzer
+ *		6/21/14
  *
  *-------------------------------------------------------------------------
  */
-static herr_t
-H5HF_cache_hdr_size(const H5F_t H5_ATTR_UNUSED *f, const H5HF_hdr_t *hdr, size_t *size_ptr)
+static herr_t 
+H5HF__cache_iblock_get_load_size(const void *_udata, size_t *image_len)
 {
-    FUNC_ENTER_NOAPI_NOINIT_NOERR
+    const H5HF_iblock_cache_ud_t *udata = (const H5HF_iblock_cache_ud_t *)_udata;   /* User data for callback */
 
-    /* Check arguments */
-    HDassert(f);
-    HDassert(hdr);
-    HDassert(size_ptr);
+    FUNC_ENTER_STATIC_NOERR
 
-    /* Set size value */
-    *size_ptr = hdr->heap_size;
+    /* Sanity checks */
+    HDassert(udata);
+    HDassert(image_len);
+   
+    *image_len = (size_t)H5HF_MAN_INDIRECT_SIZE(udata->par_info->hdr, *udata->nrows);
 
     FUNC_LEAVE_NOAPI(SUCCEED)
-} /* H5HF_cache_hdr_size() */
+} /* end H5HF__cache_iblock_get_load_size() */
 
 /***********************************************************/
 /* metadata cache callback definitions for indirect blocks */
@@ -734,53 +874,55 @@ H5HF_cache_hdr_size(const H5F_t H5_ATTR_UNUSED *f, const H5HF_hdr_t *hdr, size_t
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HF_cache_iblock_load
+ * Function:	H5HF__cache_iblock_deserialize
  *
- * Purpose:	Loads a fractal heap indirect block from the disk.
+ * Purpose:	Given a buffer containing the on disk image of the indirect 
+ *		block, allocate an instance of H5HF_indirect_t, load the data 
+ *		in the buffer into this new instance, and return a pointer to 
+ *		it.
  *
- * Return:	Success:	Pointer to a new fractal heap indirect block
+ *		As best I can tell, the size of the indirect block image is fully
+ *		know before the image is loaded, so this function should succeed
+ *		unless the image is corrupt or memory allocation fails.
  *
+ * Return:	Success:	Pointer to in core representation
  *		Failure:	NULL
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Feb 27 2006
+ * Programmer:	John Mainzer
+ *		6/21/14
  *
  *-------------------------------------------------------------------------
  */
-static H5HF_indirect_t *
-H5HF_cache_iblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
+static void *
+H5HF__cache_iblock_deserialize(const void *_image, size_t len, void *_udata,
+    hbool_t H5_ATTR_UNUSED *dirty)
 {
     H5HF_hdr_t          *hdr;           /* Shared fractal heap information */
-    H5HF_iblock_cache_ud_t *udata = (H5HF_iblock_cache_ud_t *)_udata; /* user data for callback */
-    H5HF_indirect_t	*iblock = NULL; /* Indirect block info */
-    H5WB_t              *wb = NULL;     /* Wrapped buffer for indirect block data */
-    uint8_t             iblock_buf[H5HF_IBLOCK_BUF_SIZE]; /* Buffer for indirect block */
-    uint8_t		*buf;           /* Temporary buffer */
-    const uint8_t	*p;             /* Pointer into raw data buffer */
+    H5HF_iblock_cache_ud_t *udata = (H5HF_iblock_cache_ud_t *)_udata; /* User data for callback */
+    H5HF_indirect_t     *iblock = NULL; /* Indirect block info */
+    const uint8_t       *image = (const uint8_t *)_image;       /* Pointer into raw data buffer */
     haddr_t             heap_addr;      /* Address of heap header in the file */
     uint32_t            stored_chksum;  /* Stored metadata checksum value */
     uint32_t            computed_chksum; /* Computed metadata checksum value */
     unsigned            u;              /* Local index variable */
-    H5HF_indirect_t	*ret_value;     /* Return value */
+    void *              ret_value;      /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
-    /* Check arguments */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
+    /* Sanity checks */
+    HDassert(image);
     HDassert(udata);
-
-    /* Allocate space for the fractal heap indirect block */
-    if(NULL == (iblock = H5FL_CALLOC(H5HF_indirect_t)))
-        HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed")
-
-    /* Get the pointer to the shared heap header */
+    HDassert(dirty);
     hdr = udata->par_info->hdr;
+    HDassert(hdr->f);
 
     /* Set the shared heap header's file context for this operation */
     hdr->f = udata->f;
 
+    /* Allocate space for the fractal heap indirect block */
+    if(NULL == (iblock = H5FL_CALLOC(H5HF_indirect_t)))
+        HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed")
+
     /* Share common heap information */
     iblock->hdr = hdr;
     if(H5HF_hdr_incr(hdr) < 0)
@@ -791,35 +933,23 @@ H5HF_cache_iblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
     iblock->nrows = *udata->nrows;
     iblock->nchildren = 0;
 
-    /* Wrap the local buffer for serialized indirect block */
-    if(NULL == (wb = H5WB_wrap(iblock_buf, sizeof(iblock_buf))))
-        HGOTO_ERROR(H5E_HEAP, H5E_CANTINIT, NULL, "can't wrap buffer")
-
     /* Compute size of indirect block */
     iblock->size = H5HF_MAN_INDIRECT_SIZE(hdr, iblock->nrows);
 
-    /* Get a pointer to a buffer that's large enough for serialized indirect block */
-    if(NULL == (buf = (uint8_t *)H5WB_actual(wb, iblock->size)))
-        HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, NULL, "can't get actual buffer")
-
-    /* Read indirect block from disk */
-    if(H5F_block_read(f, H5FD_MEM_FHEAP_IBLOCK, addr, iblock->size, dxpl_id, buf) < 0)
-	HGOTO_ERROR(H5E_HEAP, H5E_READERROR, NULL, "can't read fractal heap indirect block")
-
-    /* Get temporary pointer to serialized indirect block */
-    p = buf;
+    /* sanity check */
+    HDassert(iblock->size == len);
 
     /* Magic number */
-    if(HDmemcmp(p, H5HF_IBLOCK_MAGIC, (size_t)H5_SIZEOF_MAGIC))
-        HGOTO_ERROR(H5E_HEAP, H5E_CANTLOAD, NULL, "wrong fractal heap indirect block signature")
-    p += H5_SIZEOF_MAGIC;
+    if(HDmemcmp(image, H5HF_IBLOCK_MAGIC, (size_t)H5_SIZEOF_MAGIC))
+        HGOTO_ERROR(H5E_HEAP, H5E_BADVALUE, NULL, "wrong fractal heap indirect block signature")
+    image += H5_SIZEOF_MAGIC;
 
     /* Version */
-    if(*p++ != H5HF_IBLOCK_VERSION)
+    if(*image++ != H5HF_IBLOCK_VERSION)
         HGOTO_ERROR(H5E_HEAP, H5E_VERSION, NULL, "wrong fractal heap direct block version")
 
     /* Address of heap that owns this block */
-    H5F_addr_decode(udata->f, &p, &heap_addr);
+    H5F_addr_decode(udata->f, &image, &heap_addr);
     if(H5F_addr_ne(heap_addr, hdr->heap_addr))
         HGOTO_ERROR(H5E_HEAP, H5E_CANTLOAD, NULL, "incorrect heap header address for direct block")
 
@@ -844,7 +974,7 @@ H5HF_cache_iblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
     } /* end else */
 
     /* Offset of heap within the heap's address space */
-    UINT64DECODE_VAR(p, iblock->block_off, hdr->heap_off_size);
+    UINT64DECODE_VAR(image, iblock->block_off, hdr->heap_off_size);
 
     /* Allocate & decode child block entry tables */
     HDassert(iblock->nrows > 0);
@@ -866,7 +996,7 @@ H5HF_cache_iblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
 
     for(u = 0; u < (iblock->nrows * hdr->man_dtable.cparam.width); u++) {
         /* Decode child block address */
-        H5F_addr_decode(udata->f, &p, &(iblock->ents[u].addr));
+        H5F_addr_decode(udata->f, &image, &(iblock->ents[u].addr));
 
         /* Check for heap with I/O filters */
         if(hdr->filter_len > 0) {
@@ -876,7 +1006,7 @@ H5HF_cache_iblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
             /* Decode extra information for direct blocks */
             if(u < (hdr->man_dtable.max_direct_rows * hdr->man_dtable.cparam.width)) {
                 /* Size of filtered direct block */
-                H5F_DECODE_LENGTH(udata->f, p, iblock->filt_ents[u].size);
+                H5F_DECODE_LENGTH(udata->f, image, iblock->filt_ents[u].size);
 
                 /* Sanity check */
                 /* (either both the address & size are defined or both are
@@ -886,7 +1016,7 @@ H5HF_cache_iblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
                     || (!H5F_addr_defined(iblock->ents[u].addr) && iblock->filt_ents[u].size == 0));
 
                 /* I/O filter mask for filtered direct block */
-                UINT32DECODE(p, iblock->filt_ents[u].filter_mask);
+                UINT32DECODE(image, iblock->filt_ents[u].filter_mask);
             } /* end if */
         } /* end if */
 
@@ -901,13 +1031,13 @@ H5HF_cache_iblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
     HDassert(iblock->nchildren);   /* indirect blocks w/no children should have been deleted */
 
     /* Compute checksum on indirect block */
-    computed_chksum = H5_checksum_metadata(buf, (size_t)(p - (const uint8_t *)buf), 0);
+    computed_chksum = H5_checksum_metadata((const uint8_t *)_image, (size_t)(image - (const uint8_t *)_image), 0);
 
     /* Metadata checksum */
-    UINT32DECODE(p, stored_chksum);
+    UINT32DECODE(image, stored_chksum);
 
     /* Sanity check */
-    HDassert((size_t)(p - (const uint8_t *)buf) == iblock->size);
+    HDassert((size_t)(image - (const uint8_t *)_image) == iblock->size);
 
     /* Verify checksum */
     if(stored_chksum != computed_chksum)
@@ -915,7 +1045,7 @@ H5HF_cache_iblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
 
     /* Check if we have any indirect block children */
     if(iblock->nrows > hdr->man_dtable.max_direct_rows) {
-        unsigned indir_rows;      /* Number of indirect rows in this indirect block */
+        unsigned indir_rows;/* Number of indirect rows in this indirect block */
 
         /* Compute the number of indirect rows for this indirect block */
         indir_rows = iblock->nrows - hdr->man_dtable.max_direct_rows;
@@ -928,343 +1058,323 @@ H5HF_cache_iblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
         iblock->child_iblocks = NULL;
 
     /* Set return value */
-    ret_value = iblock;
+    ret_value = (void *)iblock;
 
 done:
-    /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-        HDONE_ERROR(H5E_HEAP, H5E_CLOSEERROR, NULL, "can't close wrapped buffer")
     if(!ret_value && iblock)
         if(H5HF_man_iblock_dest(iblock) < 0)
             HDONE_ERROR(H5E_HEAP, H5E_CANTFREE, NULL, "unable to destroy fractal heap indirect block")
 
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5HF_cache_iblock_load() */
+} /* end H5HF__cache_iblock_deserialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HF_cache_iblock_flush
+ * Function:	H5HF__cache_iblock_image_len
  *
- * Purpose:	Flushes a dirty fractal heap indirect block to disk.
+ * Purpose:	Return the size of the on disk image of the iblock.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:	Success:	SUCCEED
+ *		Failure:	FAIL
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Mar  6 2006
+ * Programmer:	John Mainzer
+ *		6/21/14
  *
  *-------------------------------------------------------------------------
  */
-static herr_t
-H5HF_cache_iblock_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5HF_indirect_t *iblock, unsigned H5_ATTR_UNUSED * flags_ptr)
+static herr_t 
+H5HF__cache_iblock_image_len(const void *_thing, size_t *image_len,
+    hbool_t H5_ATTR_UNUSED *compressed_ptr, size_t H5_ATTR_UNUSED *compressed_image_len_ptr)
 {
-    H5WB_t      *wb = NULL;             /* Wrapped buffer for indirect block data */
-    uint8_t     iblock_buf[H5HF_IBLOCK_BUF_SIZE]; /* Buffer for indirect block */
-    herr_t      ret_value = SUCCEED;    /* Return value */
+    const H5HF_indirect_t *iblock = (const H5HF_indirect_t *)_thing;    /* Indirect block info */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC_NOERR
 
-    /* check arguments */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
+    /* Sanity checks */
     HDassert(iblock);
+    HDassert(iblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(iblock->cache_info.type == H5AC_FHEAP_IBLOCK);
+    HDassert(image_len);
 
-    if(iblock->cache_info.is_dirty) {
-        H5HF_hdr_t *hdr;                /* Shared fractal heap information */
-        uint8_t	*buf;                   /* Temporary buffer */
-        uint8_t *p;                     /* Pointer into raw data buffer */
-#ifndef NDEBUG
-        unsigned nchildren = 0;         /* Track # of children */
-        unsigned max_child = 0;         /* Track max. child entry used */
-#endif /* NDEBUG */
-        uint32_t metadata_chksum;       /* Computed metadata checksum value */
-        size_t u;                       /* Local index variable */
-
-#ifndef NDEBUG
-{
-        /* Verify that flush dependencies are working correctly.  Do this 
-	 * by verifying that all children of this iblock are clean.
-	 */
-	hbool_t descendants_clean = TRUE;
-	unsigned iblock_status;
-
-        if(H5AC_get_entry_status(f, iblock->addr, &iblock_status) < 0)
-            HGOTO_ERROR(H5E_HEAP, H5E_CANTGET, FAIL, "can't get iblock status")
-
-	/* since the current iblock is the guest of honor in a flush, we know
-         * that it is locked into the cache for the duration of the call.  Hence
-         * there is no need to check to see if it is pinned or protected, or to
-         * protect it if it is not.
-         */
-	if(H5HF__cache_verify_iblock_descendants_clean(f, dxpl_id, iblock, &iblock_status, &descendants_clean) < 0)
-	     HGOTO_ERROR(H5E_HEAP, H5E_SYSTEM, FAIL, "can't verify descendants clean.")
-
-	HDassert(descendants_clean);
-}
-#endif /* NDEBUG */
-
-        /* Get the pointer to the shared heap header */
-        hdr = iblock->hdr;
-
-        /* Set the shared heap header's file context for this operation */
-        hdr->f = f;
-
-        /* Wrap the local buffer for serialized indirect block */
-        if(NULL == (wb = H5WB_wrap(iblock_buf, sizeof(iblock_buf))))
-            HGOTO_ERROR(H5E_HEAP, H5E_CANTINIT, FAIL, "can't wrap buffer")
-
-        /* Get a pointer to a buffer that's large enough for serialized indirect block */
-        if(NULL == (buf = (uint8_t *)H5WB_actual(wb, iblock->size)))
-            HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, FAIL, "can't get actual buffer")
-
-        /* Get temporary pointer to buffer for serialized indirect block */
-        p = buf;
-
-        /* Magic number */
-        HDmemcpy(p, H5HF_IBLOCK_MAGIC, (size_t)H5_SIZEOF_MAGIC);
-        p += H5_SIZEOF_MAGIC;
-
-        /* Version # */
-        *p++ = H5HF_IBLOCK_VERSION;
-
-        /* Address of heap header for heap which owns this block */
-        H5F_addr_encode(f, &p, hdr->heap_addr);
-
-        /* Offset of block in heap */
-        UINT64ENCODE_VAR(p, iblock->block_off, hdr->heap_off_size);
-
-        /* Encode indirect block-specific fields */
-        for(u = 0; u < (iblock->nrows * hdr->man_dtable.cparam.width); u++) {
-            /* Encode child block address */
-            H5F_addr_encode(f, &p, iblock->ents[u].addr);
+    *image_len = iblock->size;
 
-            /* Check for heap with I/O filters */
-            if(hdr->filter_len > 0) {
-                /* Sanity check */
-                HDassert(iblock->filt_ents);
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5HF__cache_iblock_image_len() */
 
-                /* Encode extra information for direct blocks */
-                if(u < (hdr->man_dtable.max_direct_rows * hdr->man_dtable.cparam.width)) {
-                    /* Sanity check */
-                    /* (either both the address & size are defined or both are
-                     *  not defined)
-                     */
-                    HDassert((H5F_addr_defined(iblock->ents[u].addr) && iblock->filt_ents[u].size)
-                        || (!H5F_addr_defined(iblock->ents[u].addr) && iblock->filt_ents[u].size == 0));
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF__cache_iblock_pre_serialize
+ *
+ * Purpose:	The primary objective of this function is to determine if the
+ *		indirect block is currently allocated in temporary file space,
+ *		and if so, to move it to real file space before the entry is 
+ *		serialized.
+ *
+ *		In debug compiles, this function also verifies that all children
+ *		of this indirect block are either clean or are not in cache.
+ *
+ * Return:	Success:	SUCCEED
+ *		Failure:	FAIL
+ *
+ * Programmer:	John Mainzer
+ *		6/21/14
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t 
+H5HF__cache_iblock_pre_serialize(const H5F_t *f, hid_t dxpl_id, void *_thing,
+    haddr_t addr, size_t H5_ATTR_UNUSED len, size_t H5_ATTR_UNUSED compressed_len,
+    haddr_t *new_addr, size_t H5_ATTR_UNUSED *new_len,
+    size_t H5_ATTR_UNUSED *new_compressed_len, unsigned *flags)
+{
+    H5HF_hdr_t          *hdr;                   /* Shared fractal heap information */
+    H5HF_indirect_t     *iblock = (H5HF_indirect_t *)_thing;    /* Indirect block info */
+    herr_t      	 ret_value = SUCCEED;    /* Return value */
 
-                    /* Size of filtered direct block */
-                    H5F_ENCODE_LENGTH(f, p, iblock->filt_ents[u].size);
+    FUNC_ENTER_STATIC
 
-                    /* I/O filter mask for filtered direct block */
-                    UINT32ENCODE(p, iblock->filt_ents[u].filter_mask);
-                } /* end if */
-            } /* end if */
+    /* Sanity checks */
+    HDassert(f);
+    HDassert(iblock);
+    HDassert(iblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(iblock->cache_info.type == H5AC_FHEAP_IBLOCK);
+    HDassert(iblock->cache_info.size == iblock->size);
+    HDassert(H5F_addr_defined(addr));
+    HDassert(H5F_addr_eq(iblock->addr, addr));
+    HDassert(new_addr);
+    HDassert(new_len);
+    HDassert(flags);
+    hdr = iblock->hdr;
+    HDassert(hdr);
+    HDassert(hdr->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(hdr->cache_info.type == H5AC_FHEAP_HDR);
 
 #ifndef NDEBUG
-            /* Count child blocks */
-            if(H5F_addr_defined(iblock->ents[u].addr)) {
-                nchildren++;
-                if(u > max_child)
-                    max_child = u;
-            } /* end if */
-#endif /* NDEBUG */
-        } /* end for */
-
-        /* Compute checksum */
-        metadata_chksum = H5_checksum_metadata(buf, (size_t)(p - buf), 0);
+{
+    hbool_t 		 descendants_clean = TRUE;
+    unsigned 		 iblock_status = 0;
 
-        /* Metadata checksum */
-        UINT32ENCODE(p, metadata_chksum);
+    /* verify that flush dependencies are working correctly.  Do this
+     * by verifying that all children of this iblock are clean.
+     */
+    if(H5AC_get_entry_status(f, iblock->addr, &iblock_status) < 0)
+        HGOTO_ERROR(H5E_HEAP, H5E_CANTGET, FAIL, "can't get iblock status")
 
-        /* Sanity check */
-        HDassert((size_t)(p - buf) == iblock->size);
-#ifndef NDEBUG
-        HDassert(nchildren == iblock->nchildren);
-        HDassert(max_child == iblock->max_child);
+    /* since the current iblock is the guest of honor in a flush, we know
+     * that it is locked into the cache for the duration of the call.  Hence
+     * there is no need to check to see if it is pinned or protected, or to
+     * protect it if it is not.
+     */
+    if(H5HF__cache_verify_iblock_descendants_clean((H5F_t *)f, dxpl_id, iblock, &iblock_status, &descendants_clean) < 0)
+         HGOTO_ERROR(H5E_HEAP, H5E_SYSTEM, FAIL, "can't verify descendants clean.")
+    HDassert(descendants_clean);
+}
 #endif /* NDEBUG */
 
-        /* Check for needing to re-allocate indirect block from 'temp.' to 'normal' file space */
-        if(H5F_IS_TMP_ADDR(f, addr)) {
-            /* Sanity check */
-            HDassert(H5F_addr_eq(iblock->addr, addr));
+    /* Check to see if we must re-allocate the iblock from temporary to 
+     * normal (AKA real) file space.
+     */
+    if(H5F_IS_TMP_ADDR(f, addr)) {
+        haddr_t iblock_addr;
 
-            /* Allocate 'normal' space for the new indirect block on disk */
-            if(HADDR_UNDEF == (addr = H5MF_alloc(f, H5FD_MEM_FHEAP_IBLOCK, dxpl_id, (hsize_t)iblock->size)))
-                HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, FAIL, "file allocation failed for fractal heap indirect block")
+        /* Allocate 'normal' space for the new indirect block on disk */
+        if(HADDR_UNDEF == (iblock_addr = H5MF_alloc((H5F_t *)f, H5FD_MEM_FHEAP_IBLOCK, dxpl_id, (hsize_t)iblock->size)))
+            HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, FAIL, "file allocation failed for fractal heap indirect block")
 
-            /* Sanity check */
-            HDassert(!H5F_addr_eq(iblock->addr, addr));
+        /* Sanity check */
+        HDassert(!H5F_addr_eq(iblock->addr, iblock_addr));
 
-            /* Let the metadata cache know the block moved */
-            if(H5AC_move_entry(f, H5AC_FHEAP_IBLOCK, iblock->addr, addr) < 0)
-                HGOTO_ERROR(H5E_HEAP, H5E_CANTMOVE, FAIL, "unable to move indirect block")
+        /* Let the metadata cache know the block moved */
+        if(H5AC_move_entry((H5F_t *)f, H5AC_FHEAP_IBLOCK, iblock->addr, iblock_addr) < 0)
+            HGOTO_ERROR(H5E_HEAP, H5E_CANTMOVE, FAIL, "unable to move indirect block")
 
-            /* Update the internal address for the block */
-            iblock->addr = addr;
+        /* Update the internal address for the block */
+        iblock->addr = iblock_addr;
 
-            /* Check for root indirect block */
-            if(NULL == iblock->parent) {
-                /* Update information about indirect block's location */
-                hdr->man_dtable.table_addr = addr;
+        /* Check for root indirect block */
+        if(NULL == iblock->parent) {
+            /* Update information about indirect block's location */
+            hdr->man_dtable.table_addr = iblock_addr;
 
-                /* Mark that heap header was modified */
-                if(H5HF_hdr_dirty(hdr) < 0)
-                    HGOTO_ERROR(H5E_HEAP, H5E_CANTDIRTY, FAIL, "can't mark heap header as dirty")
-            } /* end if */
-            else {
-                H5HF_indirect_t *par_iblock;    /* Parent indirect block */
-                unsigned par_entry;             /* Entry in parent indirect block */
+            /* Mark that heap header was modified */
+            if(H5HF_hdr_dirty(hdr) < 0)
+                HGOTO_ERROR(H5E_HEAP, H5E_CANTDIRTY, FAIL, "can't mark heap header as dirty")
+        } /* end if */
+        else {
+            H5HF_indirect_t *par_iblock;    /* Parent indirect block */
+            unsigned par_entry;             /* Entry in parent indirect block */
 
-                /* Get parent information */
-                par_iblock = iblock->parent;
-                par_entry = iblock->par_entry;
+            /* Get parent information */
+            par_iblock = iblock->parent;
+            par_entry = iblock->par_entry;
 
-                /* Update information about indirect block's location */
-                par_iblock->ents[par_entry].addr = addr;
+            /* Update information about indirect block's location */
+            par_iblock->ents[par_entry].addr = iblock_addr;
 
-                /* Mark that parent was modified */
-                if(H5HF_iblock_dirty(par_iblock) < 0)
-                    HGOTO_ERROR(H5E_HEAP, H5E_CANTDIRTY, FAIL, "can't mark heap header as dirty")
-            } /* end if */
+            /* Mark that parent was modified */
+            if(H5HF_iblock_dirty(par_iblock) < 0)
+                HGOTO_ERROR(H5E_HEAP, H5E_CANTDIRTY, FAIL, "can't mark heap header as dirty")
         } /* end if */
 
-        /* Indirect block must be in 'normal' file space now */
-        HDassert(!H5F_IS_TMP_ADDR(f, addr));
-
-	/* Write the indirect block */
-	if(H5F_block_write(f, H5FD_MEM_FHEAP_IBLOCK, addr, iblock->size, dxpl_id, buf) < 0)
-	    HGOTO_ERROR(H5E_HEAP, H5E_CANTFLUSH, FAIL, "unable to save fractal heap indirect block to disk")
-
-        /* Reset dirty flags */
-	iblock->cache_info.is_dirty = FALSE;
+	*new_addr = iblock_addr;
+        *flags = H5C__SERIALIZE_MOVED_FLAG;
     } /* end if */
-
-    if(destroy)
-        if(H5HF_cache_iblock_dest(f, iblock) < 0)
-	    HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to destroy fractal heap indirect block")
+    else 
+	*flags = 0;
 
 done:
-    /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-        HDONE_ERROR(H5E_HEAP, H5E_CLOSEERROR, FAIL, "can't close wrapped buffer")
-
     FUNC_LEAVE_NOAPI(ret_value)
-} /* H5HF_cache_iblock_flush() */
+} /* end H5HF__cache_iblock_pre_serialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HF_cache_iblock_dest
+ * Function:	H5HF__cache_iblock_serialize
  *
- * Purpose:	Destroys a fractal heap indirect block in memory.
+ * Purpose:	Given a pointer to an iblock, and a pointer to a buffer of 
+ *		the appropriate size, write the contents of the iblock to the 
+ *		buffer in format appropriate for writing to disk.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:	Success:	SUCCEED
+ *		Failure:	FAIL
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Mar  6 2006
+ * Programmer:	John Mainzer
+ *		6/21/14
  *
  *-------------------------------------------------------------------------
  */
-static herr_t
-H5HF_cache_iblock_dest(H5F_t *f, H5HF_indirect_t *iblock)
+static herr_t 
+H5HF__cache_iblock_serialize(const H5F_t *f, void *_image, size_t len,
+    void *_thing)
 {
-    herr_t      ret_value = SUCCEED;    /* Return value */
+    H5HF_hdr_t 		*hdr;           /* Shared fractal heap information */
+    H5HF_indirect_t     *iblock = (H5HF_indirect_t *)_thing;     /* Indirect block info */
+    uint8_t 		*image = (uint8_t *)_image;     /* Pointer into raw data buffer */
+#ifndef NDEBUG
+    unsigned 		 nchildren = 0; /* Track # of children */
+    size_t		 max_child = 0; /* Track max. child entry used */
+#endif /* NDEBUG */
+    uint32_t		 metadata_chksum; /* Computed metadata checksum value */
+    size_t 		 u;             /* Local index variable */
+    herr_t               ret_value = SUCCEED;    /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC_NOERR
 
-    /*
-     * Check arguments.
-     */
+    /* Sanity checks */
+    HDassert(f);
+    HDassert(image);
     HDassert(iblock);
-    HDassert(iblock->rc == 0);
-    HDassert(iblock->hdr);
+    HDassert(iblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(iblock->cache_info.type == H5AC_FHEAP_IBLOCK);
+    HDassert(iblock->cache_info.size == iblock->size);
+    HDassert(len == iblock->size);
 
-    /* If we're going to free the space on disk, the address must be valid */
-    HDassert(!iblock->cache_info.free_file_space_on_destroy || H5F_addr_defined(iblock->cache_info.addr));
-
-    /* Check for freeing file space for indirect block */
-    if(iblock->cache_info.free_file_space_on_destroy) {
-        /* Check if the indirect block is NOT currently allocated in temp. file space */
-        /* (temp. file space does not need to be freed) */
-        if(!H5F_IS_TMP_ADDR(f, iblock->cache_info.addr)) {
-            /* Release the space on disk */
-            /* (XXX: Nasty usage of internal DXPL value! -QAK) */
-            if(H5MF_xfree(f, H5FD_MEM_FHEAP_IBLOCK, H5AC_dxpl_id, iblock->cache_info.addr, (hsize_t)iblock->size) < 0)
-                HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to free fractal heap indirect block")
-        } /* end if */
-    } /* end if */
+    /* Indirect block must be in 'normal' file space */
+    HDassert(!H5F_IS_TMP_ADDR(f, iblock->addr));
+    HDassert(H5F_addr_eq(iblock->addr, iblock->cache_info.addr));
 
-    /* Destroy fractal heap indirect block */
-    if(H5HF_man_iblock_dest(iblock) < 0)
-        HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to destroy fractal heap indirect block")
+    /* Get the pointer to the shared heap header */
+    hdr = iblock->hdr;
 
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5HF_cache_iblock_dest() */
+    /* Set the shared heap header's file context for this operation */
+    hdr->f = f;
 
-
-/*-------------------------------------------------------------------------
- * Function:	H5HF_cache_iblock_clear
- *
- * Purpose:	Mark a fractal heap indirect block in memory as non-dirty.
- *
- * Return:	Non-negative on success/Negative on failure
- *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Mar  6 2006
- *
- *-------------------------------------------------------------------------
- */
-static herr_t
-H5HF_cache_iblock_clear(H5F_t *f, H5HF_indirect_t *iblock, hbool_t destroy)
-{
-    herr_t ret_value = SUCCEED;         /* Return value */
+    /* Magic number */
+    HDmemcpy(image, H5HF_IBLOCK_MAGIC, (size_t)H5_SIZEOF_MAGIC);
+    image += H5_SIZEOF_MAGIC;
 
-    FUNC_ENTER_NOAPI_NOINIT
+    /* Version # */
+    *image++ = H5HF_IBLOCK_VERSION;
 
-    /*
-     * Check arguments.
-     */
-    HDassert(iblock);
+    /* Address of heap header for heap which owns this block */
+    H5F_addr_encode(f, &image, hdr->heap_addr);
 
-    /* Reset the dirty flag.  */
-    iblock->cache_info.is_dirty = FALSE;
+    /* Offset of block in heap */
+    UINT64ENCODE_VAR(image, iblock->block_off, hdr->heap_off_size);
 
-    if(destroy)
-        if(H5HF_cache_iblock_dest(f, iblock) < 0)
-	    HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to destroy fractal heap indirect block")
+    /* Encode indirect block-specific fields */
+    for(u = 0; u < (iblock->nrows * hdr->man_dtable.cparam.width); u++) {
+        /* Encode child block address */
+        H5F_addr_encode(f, &image, iblock->ents[u].addr);
+
+        /* Check for heap with I/O filters */
+        if(hdr->filter_len > 0) {
+            /* Sanity check */
+            HDassert(iblock->filt_ents);
+
+            /* Encode extra information for direct blocks */
+            if(u < (hdr->man_dtable.max_direct_rows * hdr->man_dtable.cparam.width)) {
+                /* Sanity check */
+                /* (either both the address & size are defined or both are
+                 *  not defined)
+                 */
+                HDassert((H5F_addr_defined(iblock->ents[u].addr) && iblock->filt_ents[u].size) 
+                        || (!H5F_addr_defined(iblock->ents[u].addr) && iblock->filt_ents[u].size == 0));
+
+                /* Size of filtered direct block */
+                H5F_ENCODE_LENGTH(f, image, iblock->filt_ents[u].size);
+
+                /* I/O filter mask for filtered direct block */
+                UINT32ENCODE(image, iblock->filt_ents[u].filter_mask);
+            } /* end if */
+        } /* end if */
+
+#ifndef NDEBUG
+        /* Count child blocks */
+        if(H5F_addr_defined(iblock->ents[u].addr)) {
+            nchildren++;
+            if(u > max_child)
+                max_child = u;
+        } /* end if */
+#endif /* NDEBUG */
+    } /* end for */
+
+    /* Compute checksum */
+    metadata_chksum = H5_checksum_metadata((uint8_t *)_image, (size_t)(image - (uint8_t *)_image), 0);
+
+    /* Metadata checksum */
+    UINT32ENCODE(image, metadata_chksum);
+
+    /* Sanity checks */
+    HDassert((size_t)(image - (uint8_t *)_image) == iblock->size);
+#ifndef NDEBUG
+    HDassert(nchildren == iblock->nchildren);
+    HDassert(max_child == iblock->max_child);
+#endif /* NDEBUG */
 
-done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5HF_cache_iblock_clear() */
+} /* end H5HF__cache_iblock_serialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HF_cache_iblock_notify
+ * Function:	H5HF__cache_iblock_notify
  *
- * Purpose:	Setup / takedown flush dependencies as indirect blocks
+ * Purpose:	This function is used to create and destroy flush dependency 
+ *		relationships between iblocks and their parents as indirect blocks
  *		are loaded / inserted and evicted from the metadata cache.
  *
- * Return:	Non-negative on success/Negative on failure
+ *		In general, the parent will be another iblock, but it may be the 
+ *		header if the iblock in question is the root iblock.
+ *
+ * Return:	Success:	SUCCEED
+ *		Failure:	FAIL
  *
  * Programmer:	John Mainzer
- *		5/17/14
+ *		6/21/14
  *
  *-------------------------------------------------------------------------
  */
-static herr_t
-H5HF_cache_iblock_notify(H5C_notify_action_t action, H5HF_indirect_t *iblock)
+static herr_t 
+H5HF__cache_iblock_notify(H5C_notify_action_t action, void *_thing)
 {
-    herr_t ret_value = SUCCEED;         /* Return value */
+    H5HF_indirect_t     *iblock = (H5HF_indirect_t *)_thing;    /* Indirect block info */
+    herr_t      	 ret_value = SUCCEED;    /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
-    /*
-     * Check arguments.
-     */
+    /* Sanity checks */
     HDassert(iblock);
     HDassert(iblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(iblock->cache_info.type == H5AC_FHEAP_IBLOCK);
     HDassert(iblock->hdr);
 
     if(action == H5AC_NOTIFY_ACTION_BEFORE_EVICT)
@@ -1309,6 +1419,7 @@ H5HF_cache_iblock_notify(H5C_notify_action_t action, H5HF_indirect_t *iblock)
 
     switch(action) {
         case H5AC_NOTIFY_ACTION_AFTER_INSERT:
+        case H5AC_NOTIFY_ACTION_AFTER_LOAD:
             if(iblock->parent) {        /* this is a child iblock */
                 /* create flush dependency with parent iblock */
                 if(H5AC_create_flush_dependency(iblock->parent, iblock) < 0)
@@ -1321,6 +1432,10 @@ H5HF_cache_iblock_notify(H5C_notify_action_t action, H5HF_indirect_t *iblock)
             } /* end else */
             break;
 
+	case H5AC_NOTIFY_ACTION_AFTER_FLUSH:
+	    /* do nothing */
+	    break;
+
         case H5AC_NOTIFY_ACTION_BEFORE_EVICT:
             if(iblock->fd_parent) {     /* this is a child iblock */
                 /* destroy flush dependency with parent iblock */
@@ -1341,38 +1456,104 @@ H5HF_cache_iblock_notify(H5C_notify_action_t action, H5HF_indirect_t *iblock)
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5HF_cache_iblock_notify() */
+} /* end H5HF__cache_iblock_notify() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HF_cache_iblock_size
+ * Function:	H5HF__cache_iblock_free_icr
  *
- * Purpose:	Compute the size in bytes of a fractal heap indirect block
- *		on disk, and return it in *size_ptr.  On failure,
- *		the value of *size_ptr is undefined.
+ * Purpose:	Unlink the supplied instance of H5HF_indirect_t from the 
+ *		fractal heap and free its memory.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Note:	The metadata cache sets the object's cache_info.magic to
+ *		H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC before calling a free_icr
+ *		callback (checked in assert).
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Mar  6 2006
+ * Return:	Success:	SUCCEED
+ *		Failure:	FAIL
+ *
+ * Programmer:	John Mainzer
+ *		6/21/14
  *
  *-------------------------------------------------------------------------
  */
-static herr_t
-H5HF_cache_iblock_size(const H5F_t H5_ATTR_UNUSED *f, const H5HF_indirect_t *iblock, size_t *size_ptr)
+static herr_t 
+H5HF__cache_iblock_free_icr(void *thing)
 {
-    FUNC_ENTER_NOAPI_NOINIT_NOERR
+    H5HF_indirect_t	*iblock = (H5HF_indirect_t *)thing;     /* Fractal heap indirect block to free */
+    herr_t      	 ret_value = SUCCEED;    /* Return value */
 
-    /* Check arguments */
+    FUNC_ENTER_STATIC
+
+    /* Sanity checks */
     HDassert(iblock);
-    HDassert(size_ptr);
+    HDassert(iblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC);
+    HDassert(iblock->cache_info.type == H5AC_FHEAP_IBLOCK);
+    HDassert(iblock->rc == 0);
+    HDassert(iblock->hdr);
+
+    /* Destroy fractal heap indirect block */
+    if(H5HF_man_iblock_dest(iblock) < 0)
+        HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to destroy fractal heap indirect block")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5HF__cache_iblock_free_icr() */
+
+/*********************************************************/
+/* metadata cache callback definitions for direct blocks */
+/*********************************************************/
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF__cache_dblock_get_load_size()
+ *
+ * Purpose:	Determine the size of the direct block on disk image, and 
+ *		return it in *image_len.
+ *
+ * Return:	Success:	SUCCEED
+ *		Failure:	FAIL
+ *
+ * Programmer:	John Mainzer
+ *		6/21/14
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t 
+H5HF__cache_dblock_get_load_size(const void *_udata, size_t *image_len)
+{
+    const H5HF_dblock_cache_ud_t *udata = (const H5HF_dblock_cache_ud_t *)_udata;    /* User data for callback */
+    const H5HF_parent_t         *par_info; /* Pointer to parent information */
+    const H5HF_hdr_t            *hdr;     /* Shared fractal heap information */
+    size_t                      size;
+
+    FUNC_ENTER_STATIC_NOERR
+
+    /* Sanity checks */
+    HDassert(udata);
+    HDassert(image_len);
+    par_info = (const H5HF_parent_t *)(&(udata->par_info));
+    HDassert(par_info);
+    hdr = par_info->hdr;
+    HDassert(hdr);
+    HDassert(hdr->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(hdr->cache_info.type == H5AC_FHEAP_HDR);
+
+    /* Check for I/O filters on this heap */
+    if(hdr->filter_len > 0) {
+        /* Check for root direct block */
+        if(par_info->iblock == NULL)
+            size = hdr->pline_root_direct_size;
+        else
+            size = par_info->iblock->filt_ents[par_info->entry].size;
+    } /* end if */
+    else
+        size = udata->dblock_size;
 
-    /* Set size value */
-    *size_ptr = iblock->size;
+    *image_len = size;
 
     FUNC_LEAVE_NOAPI(SUCCEED)
-} /* H5HF_cache_iblock_size() */
+} /* end H5HF__cache_dblock_get_load_size() */
 
 /*********************************************************/
 /* metadata cache callback definitions for direct blocks */
@@ -1380,49 +1561,55 @@ H5HF_cache_iblock_size(const H5F_t H5_ATTR_UNUSED *f, const H5HF_indirect_t *ibl
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HF_cache_dblock_load
+ * Function:	H5HF__cache_dblock_deserialize
  *
- * Purpose:	Loads a fractal heap direct block from the disk.
+ * Purpose:	Given a buffer containing the on disk image of a direct
+ *		block, allocate an instance of H5HF_direct_t, load the data
+ *		in the buffer into this new instance, and return a pointer to
+ *		it.
  *
- * Return:	Success:	Pointer to a new fractal heap direct block
+ *		As best I can tell, the size of the direct block image is fully
+ *		know before the image is loaded, so this function should succeed
+ *		unless the image is corrupt or memory allocation fails.
  *
+ * Return:	Success:	Pointer to in core representation
  *		Failure:	NULL
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Feb 27 2006
+ * Programmer:	John Mainzer
+ *		6/21/14
  *
  *-------------------------------------------------------------------------
  */
-static H5HF_direct_t *
-H5HF_cache_dblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
+static void *
+H5HF__cache_dblock_deserialize(const void *_image, size_t len, void *_udata,
+    hbool_t H5_ATTR_UNUSED *dirty)
 {
     H5HF_hdr_t          *hdr;           /* Shared fractal heap information */
     H5HF_dblock_cache_ud_t *udata = (H5HF_dblock_cache_ud_t *)_udata;   /* User data for callback */
     H5HF_parent_t       *par_info;      /* Pointer to parent information */
-    H5HF_direct_t	*dblock = NULL; /* Direct block info */
-    const uint8_t	*p;             /* Pointer into raw data buffer */
+    H5HF_direct_t       *dblock = NULL; /* Direct block info */
+    const uint8_t       *image;         /* Pointer into raw data buffer */
     haddr_t             heap_addr;      /* Address of heap header in the file */
-    H5HF_direct_t	*ret_value;     /* Return value */
+    void *              ret_value;      /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
-    /* Check arguments */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
-    HDassert(udata != NULL);
-    HDassert(udata->f != NULL);
-    HDassert(udata->dblock_size > 0);
+    /* Sanity checks */
+    HDassert(_image);
+    HDassert(udata);
+    par_info = (H5HF_parent_t *)(&(udata->par_info));
+    HDassert(par_info);
+    hdr = par_info->hdr;
+    HDassert(hdr);
+    HDassert(hdr->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(hdr->cache_info.type == H5AC_FHEAP_HDR);
+    HDassert(dirty);
 
     /* Allocate space for the fractal heap direct block */
     if(NULL == (dblock = H5FL_MALLOC(H5HF_direct_t)))
         HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed")
     HDmemset(&dblock->cache_info, 0, sizeof(H5AC_info_t));
 
-    /* Get the pointer to the shared heap header */
-    par_info = (H5HF_parent_t *)(&(udata->par_info));
-    hdr = par_info->hdr;
-
     /* Set the shared heap header's file context for this operation */
     hdr->f = udata->f;
 
@@ -1435,6 +1622,10 @@ H5HF_cache_dblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
     dblock->size = udata->dblock_size;
     dblock->file_size = 0;
 
+    /* initialize fields used in serialization */
+    dblock->write_buf = NULL;
+    dblock->write_size = 0;
+
     /* Allocate block buffer */
 /* XXX: Change to using free-list factories */
     if(NULL == (dblock->blk = H5FL_BLK_MALLOC(direct_block, (size_t)dblock->size)))
@@ -1449,28 +1640,21 @@ H5HF_cache_dblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
         unsigned filter_mask;   /* Excluded filters for direct block */
 
         /* Check for root direct block */
-        if(par_info->iblock == NULL) {
-            /* Sanity check */
-            HDassert(H5F_addr_eq(hdr->man_dtable.table_addr, addr));
-
+        if(par_info->iblock == NULL)
             /* Set up parameters to read filtered direct block */
             read_size = hdr->pline_root_direct_size;
-        } /* end if */
-        else {
-            /* Sanity check */
-            HDassert(H5F_addr_eq(par_info->iblock->ents[par_info->entry].addr, addr));
-
+        else
             /* Set up parameters to read filtered direct block */
             read_size = par_info->iblock->filt_ents[par_info->entry].size;
-        } /* end else */
+        HDassert(len == read_size);
 
-        /* Allocate buffer to perform I/O filtering on */
+        /* Allocate buffer to perform I/O filtering on and copy image into
+         * it.  Must do this as H5Z_pipeline() may re-sized the buffer 
+         * provided to it.
+         */
         if(NULL == (read_buf = H5MM_malloc(read_size)))
             HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, NULL, "memory allocation failed for pipeline buffer")
-
-        /* Read filtered direct block from disk */
-        if(H5F_block_read(f, H5FD_MEM_FHEAP_DBLOCK, addr, read_size, dxpl_id, read_buf) < 0)
-            HGOTO_ERROR(H5E_HEAP, H5E_READERROR, NULL, "can't read fractal heap direct block")
+        HDmemcpy(read_buf, _image, len);
 
         /* Push direct block data through I/O filter pipeline */
         nbytes = read_size;
@@ -1488,25 +1672,25 @@ H5HF_cache_dblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
         H5MM_xfree(read_buf);
     } /* end if */
     else {
-        /* Read direct block from disk */
-        if(H5F_block_read(f, H5FD_MEM_FHEAP_DBLOCK, addr, dblock->size, dxpl_id, dblock->blk) < 0)
-            HGOTO_ERROR(H5E_HEAP, H5E_READERROR, NULL, "can't read fractal heap direct block")
+        /* copy image to dblock->blk */
+        HDassert(dblock->size == len);
+        HDmemcpy(dblock->blk, _image, dblock->size);
     } /* end else */
 
     /* Start decoding direct block */
-    p = dblock->blk;
+    image = dblock->blk;
 
     /* Magic number */
-    if(HDmemcmp(p, H5HF_DBLOCK_MAGIC, (size_t)H5_SIZEOF_MAGIC))
-        HGOTO_ERROR(H5E_HEAP, H5E_CANTLOAD, NULL, "wrong fractal heap direct block signature")
-    p += H5_SIZEOF_MAGIC;
+    if(HDmemcmp(image, H5HF_DBLOCK_MAGIC, (size_t)H5_SIZEOF_MAGIC))
+        HGOTO_ERROR(H5E_HEAP, H5E_BADVALUE, NULL, "wrong fractal heap direct block signature")
+    image += H5_SIZEOF_MAGIC;
 
     /* Version */
-    if(*p++ != H5HF_DBLOCK_VERSION)
+    if(*image++ != H5HF_DBLOCK_VERSION)
         HGOTO_ERROR(H5E_HEAP, H5E_VERSION, NULL, "wrong fractal heap direct block version")
 
     /* Address of heap that owns this block (just for file integrity checks) */
-    H5F_addr_decode(udata->f, &p, &heap_addr);
+    H5F_addr_decode(udata->f, &image, &heap_addr);
     if(H5F_addr_ne(heap_addr, hdr->heap_addr))
         HGOTO_ERROR(H5E_HEAP, H5E_CANTLOAD, NULL, "incorrect heap header address for direct block")
 
@@ -1521,7 +1705,7 @@ H5HF_cache_dblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
     } /* end if */
 
     /* Offset of heap within the heap's address space */
-    UINT64DECODE_VAR(p, dblock->block_off, hdr->heap_off_size);
+    UINT64DECODE_VAR(image, dblock->block_off, hdr->heap_off_size);
 
     /* Decode checksum on direct block, if requested */
     if(hdr->checksum_dblocks) {
@@ -1529,11 +1713,11 @@ H5HF_cache_dblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
         uint32_t computed_chksum;       /* Computed metadata checksum value */
 
         /* Metadata checksum */
-        UINT32DECODE(p, stored_chksum);
+        UINT32DECODE(image, stored_chksum);
 
         /* Reset checksum field, for computing the checksum */
         /* (Casting away const OK - QAK) */
-        HDmemset((uint8_t *)p - H5HF_SIZEOF_CHKSUM, 0, (size_t)H5HF_SIZEOF_CHKSUM);
+        HDmemset((uint8_t *)image - H5HF_SIZEOF_CHKSUM, 0, (size_t)H5HF_SIZEOF_CHKSUM);
 
         /* Compute checksum on entire direct block */
         computed_chksum = H5_checksum_metadata(dblock->blk, dblock->size, 0);
@@ -1544,10 +1728,10 @@ H5HF_cache_dblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
     } /* end if */
 
     /* Sanity check */
-    HDassert((size_t)(p - dblock->blk) == (size_t)H5HF_MAN_ABS_DIRECT_OVERHEAD(hdr));
+    HDassert((size_t)(image - dblock->blk) == (size_t)H5HF_MAN_ABS_DIRECT_OVERHEAD(hdr));
 
     /* Set return value */
-    ret_value = dblock;
+    ret_value = (void *)dblock;
 
 done:
     if(!ret_value && dblock)
@@ -1555,402 +1739,646 @@ done:
             HDONE_ERROR(H5E_HEAP, H5E_CANTFREE, NULL, "unable to destroy fractal heap direct block")
 
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5HF_cache_dblock_load() */
+} /* end H5HF__cache_dblock_deserialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HF_cache_dblock_flush
+ * Function:	H5HF__cache_dblock_image_len
  *
- * Purpose:	Flushes a dirty fractal heap direct block to disk.
+ * Purpose:	Report the actual size of the direct block image on disk.
+ *		Note that this value will probably be incorrect if compression 
+ *		is enabled and the entry is dirty.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:	Success:	SUCCEED
+ *		Failure:	FAIL
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Feb 27 2006
+ * Programmer:	John Mainzer
+ *		6/21/14
  *
  *-------------------------------------------------------------------------
  */
-static herr_t
-H5HF_cache_dblock_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5HF_direct_t *dblock, unsigned H5_ATTR_UNUSED * flags_ptr)
+static herr_t 
+H5HF__cache_dblock_image_len(const void *_thing, size_t *image_len, hbool_t *compressed_ptr, size_t *compressed_image_len_ptr)
 {
-    herr_t      ret_value = SUCCEED;    /* Return value */
+    const H5HF_direct_t    *dblock = (const H5HF_direct_t *)_thing;     /* Direct block info */
+    const H5HF_indirect_t  *par_iblock; /* Parent iblock */
+    const H5HF_hdr_t  *hdr;             /* Shared fractal heap information */
+    hbool_t	      compressed;
+    size_t            size;
+    size_t	      compressed_size;
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC_NOERR
 
-    /* check arguments */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
+    /* Sanity checks */
     HDassert(dblock);
+    HDassert(dblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(dblock->cache_info.type == H5AC_FHEAP_DBLOCK);
+    HDassert(image_len);
+    HDassert(compressed_ptr);
+    HDassert(compressed_image_len_ptr);
 
-    if(dblock->cache_info.is_dirty) {
-        H5HF_hdr_t *hdr;        /* Shared fractal heap information */
-        hbool_t at_tmp_addr = H5F_IS_TMP_ADDR(f, addr);     /* Flag to indicate direct block is at temporary address */
-        void *write_buf;        /* Pointer to buffer to write out */
-        size_t write_size;      /* Size of buffer to write out */
-        uint8_t *p;             /* Pointer into raw data buffer */
+    /* Set up convenience variables */
+    hdr = dblock->hdr;
+    par_iblock = dblock->parent;
 
-        /* Get the pointer to the shared heap header */
-        hdr = dblock->hdr;
+    /* Check for I/O filters on this heap */
+    if(hdr->filter_len > 0) {
 
-        /* Set the shared heap header's file context for this operation */
-        hdr->f = f;
+        /* Filters are enabled, so set compressed to TRUE, and set 
+ 	 * size equal to the uncompressed size of the direct block.
+         * If the data is available, set compressed_size to the compressed
+         * size of the direct block -- otherwise set it equal to the 
+         * uncompressed size.  
+         *
+         * We have three possible scenarios here.
+         *
+         * First, the block may never have been flushed.  In this
+         * case, both dblock->file_size and the size stored in the 
+         * parent (either the header or the parent iblock) will all 
+         * be zero.  In this case, return the uncompressed size 
+         * stored in dblock->size as the compressed size.
+         *
+         * Second, the block may have just been serialized, in which
+         * case, dblock->file_size should be zero, and the correct 
+         * on disk size should be stored in the parent (again, either
+         * the header or the parent iblock as case may be).
+         * 
+         * Third, we may be in the process of discarding this 
+         * dblock without writing it.  In this case, dblock->file_size
+         * should be non-zero and have the correct size.  Note that 
+         * in this case, the direct block will have been detached,
+         * and thus looking up the parent will likely return incorrect
+         * data.
+         */
+        size            = dblock->size;
+        compressed      = TRUE;
+        compressed_size = dblock->size; /* will overwrite if compressed 
+                                         * size is available.
+                                         */
+
+        if(dblock->file_size != 0) 
+            compressed_size = dblock->file_size;
+        else {
+            if(par_iblock) {
+                unsigned          par_entry;  /* Entry in parent indirect block */
 
-        HDassert(dblock->blk);
-        p = dblock->blk;
+                par_entry = dblock->par_entry;
+                compressed_size = par_iblock->filt_ents[par_entry].size;
 
-        /* Magic number */
-        HDmemcpy(p, H5HF_DBLOCK_MAGIC, (size_t)H5_SIZEOF_MAGIC);
-        p += H5_SIZEOF_MAGIC;
+            } /* end if */
+            else {
+                compressed_size = hdr->pline_root_direct_size;
+            }
 
-        /* Version # */
-        *p++ = H5HF_DBLOCK_VERSION;
+            if(compressed_size == 0)
+                compressed_size = dblock->size;
 
-        /* Address of heap header for heap which owns this block */
-        H5F_addr_encode(f, &p, hdr->heap_addr);
+        } /* end else */
+    } /* end if */
+    else {
+        size = dblock->size;
+        compressed = FALSE;
+        compressed_size = 0; /* a convenient, invalid value */
+    }
 
-        /* Offset of block in heap */
-        UINT64ENCODE_VAR(p, dblock->block_off, hdr->heap_off_size);
+    HDassert(size > 0);
 
-        /* Metadata checksum */
-        if(hdr->checksum_dblocks) {
-            uint32_t metadata_chksum;       /* Computed metadata checksum value */
+    *image_len                = size;
+    *compressed_ptr           = compressed;
+    *compressed_image_len_ptr = compressed_size;
 
-            /* Clear the checksum field, to compute the checksum */
-            HDmemset(p, 0, (size_t)H5HF_SIZEOF_CHKSUM);
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5HF__cache_dblock_image_len() */
 
-            /* Compute checksum on entire direct block */
-            metadata_chksum = H5_checksum_metadata(dblock->blk, dblock->size, 0);
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF__cache_dblock_pre_serialize
+ *
+ * Purpose:	In principle, the purpose of this function is to determine
+ *		the size and location of the disk image of the target direct 
+ *		block.  In this case, the uncompressed size of the block is
+ *		fixed, but sined the H5C__CLASS_COMPRESSED_FLAG is set, 
+ *		we may need to compute and report the compressed size.
+ *
+ *		This is a bit sticky in the case of a direct block when I/O 
+ *		filters are enabled, as the size of the compressed version
+ *		of the on disk image is not known until the direct block has 
+ *		been run through the filters.  Further, the location of the 
+ *		on disk image may change if the compressed size of the image 
+ *		changes as well.
+ *
+ *		To complicate matters further, the direct block may have been 
+ *		initially allocated in temporary (AKA imaginary) file space. 
+ *		In this case, we must relocate the direct block's on disk 
+ *		image to real file space regardless of whether it has changed 
+ *		size.
+ *
+ *		One simplifying factor is the direct block's "blk" field, 
+ *		which contains a pointer to a buffer which (with the exception
+ *		of a small header) contains the on disk image in uncompressed 
+ *		form.
+ *
+ *		To square this particular circle, this function does 
+ *		everything the serialize function usually does, with the 
+ *		exception of copying the image into the image buffer provided 
+ *		to the serialize function by the metadata cache.  The data to 
+ *		copy is provided to the serialize function in a buffer pointed
+ *		to by the write_buf field.
+ *
+ *		If I/O filters are enabled, on exit, 
+ *		H5HF__cache_dblock_pre_serialize() sets the write_buf field to 
+ *		point to a buffer containing the filtered image of the direct
+ *		block.  The serialize function should free this block, and set
+ *		the write_buf field to NULL after copying it into the image 
+ *		buffer provided by the metadata cache.
+ *
+ *		If I/O filters are not enabled, this function prepares 
+ *		the buffer pointed to by the blk field for copying to the 
+ *		image buffer provided by the metadata cache, and sets the 
+ *		write_buf field equal to the blk field.  In this case, the 
+ *		serialize function should simply set the write_buf field to 
+ *		NULL after copying the direct block image into the image 
+ *		buffer.
+ *
+ *		In both of the above cases, the length of the buffer pointed 
+ *		to by write_buf is provided in the write_len field.  This 
+ *		field must contain 0 on entry to this function, and should 
+ *		be set back to 0 at the end of the serialize function.
+ *
+ * Return:	Success:	SUCCEED
+ *		Failure:	FAIL
+ *
+ * Programmer:	John Mainzer
+ *		6/21/14
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t 
+H5HF__cache_dblock_pre_serialize(const H5F_t *f, hid_t dxpl_id, void *_thing,
+    haddr_t addr, size_t len, size_t compressed_len, haddr_t *new_addr, 
+    size_t H5_ATTR_UNUSED *new_len, size_t *new_compressed_len, unsigned *flags)
+{
+    hbool_t 		 at_tmp_addr;  /* Flag to indicate direct block is */
+                                       /* at temporary address */
+    haddr_t		 dblock_addr;
+    H5HF_hdr_t          *hdr;           /* Shared fractal heap information */
+    H5HF_direct_t       *dblock = (H5HF_direct_t *)_thing;      /* Direct block info */
+    H5HF_indirect_t 	*par_iblock;    /* Parent indirect block */
+    unsigned		 par_entry;     /* Entry in parent indirect block */
+    void 		*write_buf;     /* Pointer to buffer to write out */
+    size_t 		 write_size;    /* Size of buffer to write out */
+    uint8_t 		*image;         /* Pointer into raw data buffer */
+    unsigned		 dblock_flags = 0;
+    herr_t               ret_value = SUCCEED;    /* Return value */
 
-            /* Metadata checksum */
-            UINT32ENCODE(p, metadata_chksum);
-        } /* end if */
+    FUNC_ENTER_STATIC
 
-        /* Sanity check */
-        HDassert((size_t)(p - dblock->blk) == (size_t)H5HF_MAN_ABS_DIRECT_OVERHEAD(hdr));
+    /* Sanity checks */
+    HDassert(f);
+    HDassert(dblock);
+    HDassert(dblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(dblock->cache_info.type == H5AC_FHEAP_DBLOCK);
+    HDassert(dblock->write_buf == NULL);
+    HDassert(dblock->write_size == 0);
+    HDassert(dblock->cache_info.size == len);
+    HDassert(H5F_addr_defined(addr));
+    HDassert(len == dblock->size);
+    HDassert(new_addr);
+    HDassert(new_compressed_len);
+    HDassert(flags);
 
-        /* Check for I/O filters on this heap */
-        if(hdr->filter_len > 0) {
-            H5Z_cb_t filter_cb = {NULL, NULL};  /* Filter callback structure */
-            size_t nbytes;                      /* Number of bytes used */
-            unsigned filter_mask = 0;           /* Filter mask for block */
+    /* Set up local variables */
+    hdr = dblock->hdr;
+    dblock_addr = addr;    /* will update dblock_addr if we move the block */
 
-            /* Allocate buffer to perform I/O filtering on */
-            write_size = dblock->size;
-            if(NULL == (write_buf = H5MM_malloc(write_size)))
-                HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, FAIL, "memory allocation failed for pipeline buffer")
-            HDmemcpy(write_buf, dblock->blk, write_size);
+    /* dblock->size must match dblock->cache_info.size */
+    HDassert(dblock->cache_info.size == dblock->size);
 
-            /* Push direct block data through I/O filter pipeline */
-            nbytes = write_size;
-            if(H5Z_pipeline(&(hdr->pline), 0, &filter_mask, H5Z_ENABLE_EDC, filter_cb, &nbytes, &write_size, &write_buf) < 0)
-                HGOTO_ERROR(H5E_HEAP, H5E_WRITEERROR, FAIL, "output pipeline failed")
+    /* Set the shared heap header's file context for this operation */
+    hdr->f = (H5F_t *)f;
 
-            /* Use the compressed number of bytes as the size to write */
-            write_size = nbytes;
+    HDassert(hdr);
+    HDassert(hdr->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(hdr->cache_info.type == H5AC_FHEAP_HDR);
 
-            /* Check for root direct block */
-            if(dblock->parent == NULL) {
-                hbool_t hdr_changed = FALSE;    /* Whether the header information changed */
+    if(dblock->parent) {
+	/* this is the common case, in which the direct block is the child 
+         * of an indirect block.  Set up the convenience variables we will
+         * need if the address and/or compressed size of the on disk image 
+         * of the direct block changes, and do some sanity checking in 
+         * passing.
+         */
+        par_iblock = dblock->parent;
+	par_entry = dblock->par_entry;
 
-                /* Sanity check */
-                HDassert(H5F_addr_eq(hdr->man_dtable.table_addr, addr));
-                HDassert(hdr->pline_root_direct_size > 0);
+	HDassert(par_iblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+	HDassert(par_iblock->cache_info.type == H5AC_FHEAP_IBLOCK);
+        HDassert(H5F_addr_eq(par_iblock->ents[par_entry].addr, addr));
+    } /* end if */
+    else {
+	/* the direct block is a root direct block -- just set par_iblock
+         * to NULL, as the field will not be used.
+         */
+	par_iblock = NULL;
+    } /* end else */
 
-                /* Check if the filter mask changed */
-                if(hdr->pline_root_direct_filter_mask != filter_mask) {
-                    hdr->pline_root_direct_filter_mask = filter_mask;
-                    hdr_changed = TRUE;
-                } /* end if */
+    at_tmp_addr = H5F_IS_TMP_ADDR(f, addr);
 
-                /* Check if we need to re-size the block on disk */
-                if(hdr->pline_root_direct_size != write_size || at_tmp_addr) {
-                    /* Check if the direct block is NOT currently allocated in temp. file space */
-                    /* (temp. file space does not need to be freed) */
-                    if(!at_tmp_addr) {
-                        /* Release direct block's current disk space */
-                        if(H5MF_xfree(f, H5FD_MEM_FHEAP_DBLOCK, dxpl_id, addr, (hsize_t)hdr->pline_root_direct_size) < 0)
-                            HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to free fractal heap direct block")
-                    } /* end if */
+    /* Begin by preping the direct block to be written to disk.  Do
+     * this by writing the correct magic number, the dblock version, 
+     * the address of the header, the offset of the block in the heap, 
+     * and the checksum at the beginning of the block.
+     */
 
-                    /* Allocate space for the compressed direct block */
-                    if(HADDR_UNDEF == (addr = H5MF_alloc(f, H5FD_MEM_FHEAP_DBLOCK, dxpl_id, (hsize_t)write_size)))
-                        HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, FAIL, "file allocation failed for fractal heap direct block")
+    HDassert(dblock->blk);
+    image = dblock->blk;
 
-                    /* Let the metadata cache know, if the block moved */
-                    if(!H5F_addr_eq(hdr->man_dtable.table_addr, addr))
-                        if(H5AC_move_entry(f, H5AC_FHEAP_DBLOCK, hdr->man_dtable.table_addr, addr) < 0)
-                            HGOTO_ERROR(H5E_HEAP, H5E_CANTMOVE, FAIL, "unable to move direct block")
+    /* Magic number */
+    HDmemcpy(image, H5HF_DBLOCK_MAGIC, (size_t)H5_SIZEOF_MAGIC);
+    image += H5_SIZEOF_MAGIC;
 
-                    /* Update information about compressed direct block's location & size */
-                    hdr->man_dtable.table_addr = addr;
-                    hdr->pline_root_direct_size = write_size;
+    /* Version # */
+    *image++ = H5HF_DBLOCK_VERSION;
 
-                    /* Note that heap header was modified */
-                    hdr_changed = TRUE;
-                } /* end if */
+    /* Address of heap header for heap which owns this block */
+    H5F_addr_encode(f, &image, hdr->heap_addr);
 
-                /* Check if heap header was modified */
-                if(hdr_changed)
-                    if(H5HF_hdr_dirty(hdr) < 0)
-                        HGOTO_ERROR(H5E_HEAP, H5E_CANTDIRTY, FAIL, "can't mark heap header as dirty")
-            } /* end if */
-            else {
-                hbool_t par_changed = FALSE;    /* Whether the parent's information changed */
-                H5HF_indirect_t *par_iblock;    /* Parent indirect block */
-                unsigned par_entry;             /* Entry in parent indirect block */
+    /* Offset of block in heap */
+    UINT64ENCODE_VAR(image, dblock->block_off, hdr->heap_off_size);
 
-                /* Get parent information */
-                par_iblock = dblock->parent;
-                par_entry = dblock->par_entry;
+    /* Metadata checksum */
+    if(hdr->checksum_dblocks) {
+        uint32_t metadata_chksum;       /* Computed metadata checksum value */
 
-                /* Sanity check */
-                HDassert(H5F_addr_eq(par_iblock->ents[par_entry].addr, addr));
-                HDassert(par_iblock->filt_ents[par_entry].size > 0);
+        /* Clear the checksum field, to compute the checksum */
+        HDmemset(image, 0, (size_t)H5HF_SIZEOF_CHKSUM);
 
-                /* Check if the filter mask changed */
-                if(par_iblock->filt_ents[par_entry].filter_mask != filter_mask) {
-                    par_iblock->filt_ents[par_entry].filter_mask = filter_mask;
-                    par_changed = TRUE;
-                } /* end if */
+        /* Compute checksum on entire direct block */
+        metadata_chksum = H5_checksum_metadata(dblock->blk, dblock->size, 0);
 
-                /* Check if we need to re-size the block on disk */
-                if(par_iblock->filt_ents[par_entry].size != write_size || at_tmp_addr) {
-                    /* Check if the direct block is NOT currently allocated in temp. file space */
-                    /* (temp. file space does not need to be freed) */
-                    if(!at_tmp_addr) {
-                        /* Release direct block's current disk space */
-                        if(H5MF_xfree(f, H5FD_MEM_FHEAP_DBLOCK, dxpl_id, addr, (hsize_t)par_iblock->filt_ents[par_entry].size) < 0)
-                            HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to free fractal heap direct block")
-                    } /* end if */
+        /* Metadata checksum */
+        UINT32ENCODE(image, metadata_chksum);
+    } /* end if */
 
-                    /* Allocate space for the compressed direct block */
-                    if(HADDR_UNDEF == (addr = H5MF_alloc(f, H5FD_MEM_FHEAP_DBLOCK, dxpl_id, (hsize_t)write_size)))
-                        HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, FAIL, "file allocation failed for fractal heap direct block")
+    /* at this point, dblock->blk should point to an uncompressed image of 
+     * the direct block.  If I/O filters are not enabled, this image should
+     * be ready to hand off to the metadata cache.
+     */
 
-                    /* Let the metadata cache know, if the block moved */
-                    if(!H5F_addr_eq(par_iblock->ents[par_entry].addr, addr))
-                        if(H5AC_move_entry(f, H5AC_FHEAP_DBLOCK, par_iblock->ents[par_entry].addr, addr) < 0)
-                            HGOTO_ERROR(H5E_HEAP, H5E_CANTMOVE, FAIL, "unable to move direct block")
+    /* Sanity check */
+    HDassert((size_t)(image - dblock->blk) == (size_t)H5HF_MAN_ABS_DIRECT_OVERHEAD(hdr));
 
-                    /* Update information about compressed direct block's location & size */
-                    par_iblock->ents[par_entry].addr = addr;
-                    par_iblock->filt_ents[par_entry].size = write_size;
+    /* If I/O filters are enabled on this heap, we must run the direct block
+     * image through the filters to obtain the image that we will hand off
+     * to the metadata cache.
+     */
 
-                    /* Note that parent was modified */
-                    par_changed = TRUE;
-                } /* end if */
+    /* Check for I/O filters on this heap */
+    if(hdr->filter_len > 0) {
+        H5Z_cb_t filter_cb = {NULL, NULL};  /* Filter callback structure */
+        size_t nbytes;                      /* Number of bytes used */
+        unsigned filter_mask = 0;           /* Filter mask for block */
 
-                /* Check if parent was modified */
-                if(par_changed)
-                    if(H5HF_iblock_dirty(par_iblock) < 0)
-                        HGOTO_ERROR(H5E_HEAP, H5E_CANTDIRTY, FAIL, "can't mark heap header as dirty")
-            } /* end else */
-        } /* end if */
-        else {
-            write_buf = dblock->blk;
-            write_size = dblock->size;
+        /* Allocate buffer to perform I/O filtering on */
+        write_size = dblock->size;
 
-            /* Check for needing to re-allocate direct block from 'temp.' to 'normal' file space */
-            if(at_tmp_addr) {
-                /* Check for root direct block */
-                if(NULL == dblock->parent) {
-                    /* Sanity check */
-                    HDassert(H5F_addr_eq(hdr->man_dtable.table_addr, addr));
+        if(NULL == (write_buf = H5MM_malloc(write_size)))
+            HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, FAIL, "memory allocation failed for pipeline buffer")
+        HDmemcpy(write_buf, dblock->blk, write_size);
 
-                    /* Allocate 'normal' space for the direct block */
-                    if(HADDR_UNDEF == (addr = H5MF_alloc(f, H5FD_MEM_FHEAP_DBLOCK, dxpl_id, (hsize_t)write_size)))
-                        HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, FAIL, "file allocation failed for fractal heap direct block")
+        /* Push direct block data through I/O filter pipeline */
+        nbytes = write_size;
+        if(H5Z_pipeline(&(hdr->pline), 0, &filter_mask, H5Z_ENABLE_EDC, filter_cb, &nbytes, &write_size, &write_buf) < 0)
+            HGOTO_ERROR(H5E_HEAP, H5E_WRITEERROR, FAIL, "output pipeline failed")
+
+        /* Use the compressed number of bytes as the size to write */
+        write_size = nbytes;
+
+        /* If the size and/or location of the on disk image of the 
+         * direct block changes, we must touch up its parent to reflect
+         * these changes.  Do this differently depending on whether the
+         * direct block's parent is an indirect block or (rarely) the 
+         * fractal heap header.  In this case, the direct block is known
+         * as a root direct block.
+         */
 
-                    /* Sanity check */
-                    HDassert(!H5F_addr_eq(hdr->man_dtable.table_addr, addr));
+        /* Check for root direct block */
+        if(dblock->parent == NULL) {
+            hbool_t hdr_changed = FALSE; /* Whether the header info changed */
 
-                    /* Let the metadata cache know the block moved */
-                    if(H5AC_move_entry(f, H5AC_FHEAP_DBLOCK, hdr->man_dtable.table_addr, addr) < 0)
-                        HGOTO_ERROR(H5E_HEAP, H5E_CANTMOVE, FAIL, "unable to move direct block")
+            /* Sanity check */
+            HDassert(H5F_addr_eq(hdr->man_dtable.table_addr, addr));
+            HDassert(hdr->pline_root_direct_size > 0);
 
-                    /* Update information about direct block's location */
-                    hdr->man_dtable.table_addr = addr;
+            /* Check if the filter mask changed */
+            if(hdr->pline_root_direct_filter_mask != filter_mask) {
+                hdr->pline_root_direct_filter_mask = filter_mask;
+                hdr_changed = TRUE;
+            } /* end if */
+
+            /* verify that the cache's last record of the compressed 
+             * size matches the heap's last record.  This value will
+             * likely change shortly.
+             */
+            HDassert(compressed_len == hdr->pline_root_direct_size);
 
-                    /* Mark that heap header was modified */
-                    if(H5HF_hdr_dirty(hdr) < 0)
-                        HGOTO_ERROR(H5E_HEAP, H5E_CANTDIRTY, FAIL, "can't mark heap header as dirty")
+            /* Check if we need to re-size the block on disk */
+            if(hdr->pline_root_direct_size != write_size || at_tmp_addr) {
+                /* Check if the direct block is NOT currently allocated 
+                 * in temp. file space 
+                 *
+                 * (temp. file space does not need to be freed) 
+                 */
+                if(!at_tmp_addr) {
+                    /* Release direct block's current disk space */
+                    if(H5MF_xfree(f, H5FD_MEM_FHEAP_DBLOCK, dxpl_id, addr, (hsize_t)hdr->pline_root_direct_size) < 0)
+                        HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to free fractal heap direct block")
                 } /* end if */
-                else {
-                    H5HF_indirect_t *par_iblock;    /* Parent indirect block */
-                    unsigned par_entry;             /* Entry in parent indirect block */
 
-                    /* Get parent information */
-                    par_iblock = dblock->parent;
-                    par_entry = dblock->par_entry;
+                /* Allocate space for the compressed direct block */
+                if(HADDR_UNDEF == (dblock_addr = H5MF_alloc((H5F_t *)f, H5FD_MEM_FHEAP_DBLOCK, dxpl_id, (hsize_t)write_size)))
+                    HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, FAIL, "file allocation failed for fractal heap direct block")
 
-                    /* Sanity check */
-                    HDassert(H5F_addr_eq(par_iblock->ents[par_entry].addr, addr));
+                /* Let the metadata cache know, if the block moved */
+                if(!H5F_addr_eq(hdr->man_dtable.table_addr, dblock_addr))
+                    if(H5AC_move_entry((H5F_t *)f, H5AC_FHEAP_DBLOCK, hdr->man_dtable.table_addr, dblock_addr) < 0)
+                        HGOTO_ERROR(H5E_HEAP, H5E_CANTMOVE, FAIL, "unable to move direct block")
 
-                    /* Allocate 'normal' space for the direct block */
-                    if(HADDR_UNDEF == (addr = H5MF_alloc(f, H5FD_MEM_FHEAP_DBLOCK, dxpl_id, (hsize_t)write_size)))
-                        HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, FAIL, "file allocation failed for fractal heap direct block")
+                /* Update information about compressed direct block's 
+                 * location & size 
+                 */
+                HDassert(hdr->man_dtable.table_addr == addr);
+                HDassert(hdr->pline_root_direct_size == compressed_len);
+                hdr->man_dtable.table_addr = dblock_addr;
+                hdr->pline_root_direct_size = write_size;
 
-                    /* Sanity check */
-                    HDassert(!H5F_addr_eq(par_iblock->ents[par_entry].addr, addr));
+                /* Note that heap header was modified */
+                hdr_changed = TRUE;
+            } /* end if */
+
+            /* Check if heap header was modified */
+            if(hdr_changed)
+                if(H5HF_hdr_dirty(hdr) < 0)
+                    HGOTO_ERROR(H5E_HEAP, H5E_CANTDIRTY, FAIL, "can't mark heap header as dirty")
+        } /* end if */
+        else { /* the direct block's parent is an indirect block */
+            hbool_t par_changed = FALSE;  /* Whether the parent's infochanged */
 
-                    /* Let the metadata cache know the block moved */
-                    if(H5AC_move_entry(f, H5AC_FHEAP_DBLOCK, par_iblock->ents[par_entry].addr, addr) < 0)
+            /* Sanity check */
+            HDassert(par_iblock);
+            HDassert(par_iblock->filt_ents[par_entry].size > 0);
+
+            /* Check if the filter mask changed */
+            if(par_iblock->filt_ents[par_entry].filter_mask != filter_mask) {
+                par_iblock->filt_ents[par_entry].filter_mask = filter_mask;
+                par_changed = TRUE;
+            } /* end if */
+
+            /* verify that the cache's last record of the compressed 
+             * size matches the heap's last record.  This value will
+             * likely change shortly.
+             */
+            HDassert(compressed_len == par_iblock->filt_ents[par_entry].size);
+
+            /* Check if we need to re-size the block on disk */
+            if(par_iblock->filt_ents[par_entry].size != write_size || at_tmp_addr) {
+                /* Check if the direct block is NOT currently allocated 
+                 * in temp. file space 
+                 *
+                 * (temp. file space does not need to be freed) 
+                 */
+                if(!at_tmp_addr) {
+                    /* Release direct block's current disk space */
+                    if(H5MF_xfree(f, H5FD_MEM_FHEAP_DBLOCK, dxpl_id, addr, (hsize_t)par_iblock->filt_ents[par_entry].size) < 0)
+                        HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to free fractal heap direct block")
+                } /* end if */
+
+                /* Allocate space for the compressed direct block */
+                if(HADDR_UNDEF == (dblock_addr = H5MF_alloc((H5F_t *)f, H5FD_MEM_FHEAP_DBLOCK, dxpl_id, (hsize_t)write_size)))
+                    HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, FAIL, "file allocation failed for fractal heap direct block")
+
+                /* Let the metadata cache know, if the block moved */
+                if(!H5F_addr_eq(par_iblock->ents[par_entry].addr, dblock_addr))
+                    if(H5AC_move_entry((H5F_t *)f, H5AC_FHEAP_DBLOCK, par_iblock->ents[par_entry].addr, dblock_addr) < 0)
                         HGOTO_ERROR(H5E_HEAP, H5E_CANTMOVE, FAIL, "unable to move direct block")
 
-                    /* Update information about direct block's location */
-                    par_iblock->ents[par_entry].addr = addr;
+                /* Update information about compressed direct block's 
+                 * location & size 
+                 */
+                HDassert(par_iblock->ents[par_entry].addr == addr);
+                HDassert(par_iblock->filt_ents[par_entry].size == compressed_len);
+                par_iblock->ents[par_entry].addr = dblock_addr;
+                par_iblock->filt_ents[par_entry].size = write_size;
 
-                    /* Mark that parent was modified */
-                    if(H5HF_iblock_dirty(par_iblock) < 0)
-                        HGOTO_ERROR(H5E_HEAP, H5E_CANTDIRTY, FAIL, "can't mark heap header as dirty")
-                } /* end else */
+                /* Note that parent was modified */
+                par_changed = TRUE;
             } /* end if */
+
+            /* Check if parent was modified */
+            if(par_changed)
+                if(H5HF_iblock_dirty(par_iblock) < 0)
+                    HGOTO_ERROR(H5E_HEAP, H5E_CANTDIRTY, FAIL, "can't mark heap header as dirty")
         } /* end else */
+    } /* end if */
+    else {
+        /* I/O filters are not enabled -- thus all we need to do is check to 
+         * see if the direct block is in temporary (AKA imaginary) file 
+         * space, and move it to real file space if it is.
+         *
+         * As in the I/O filters case above, we will have to touch up the 
+         * direct blocks parent if the direct block is relocated.
+         *
+         * Recall that temporary file space need not be freed, which 
+         * simplifies matters slightly.
+         */
+        write_buf = dblock->blk;
+        write_size = dblock->size;
 
-        /* Direct block must be in 'normal' file space now */
-        HDassert(!H5F_IS_TMP_ADDR(f, addr));
+        /* Check to see if we must re-allocate direct block from 'temp.' 
+         * to 'normal' file space 
+         */
+        if(at_tmp_addr) {
+            /* Check for root direct block */
+            if(NULL == dblock->parent) {
+                /* Sanity check */
+                HDassert(H5F_addr_eq(hdr->man_dtable.table_addr, addr));
 
-	/* Write the direct block */
-	if(H5F_block_write(f, H5FD_MEM_FHEAP_DBLOCK, addr, write_size, dxpl_id, write_buf) < 0)
-	    HGOTO_ERROR(H5E_HEAP, H5E_CANTFLUSH, FAIL, "unable to save fractal heap direct block to disk")
+                /* Allocate 'normal' space for the direct block */
+                if(HADDR_UNDEF == (dblock_addr = H5MF_alloc((H5F_t *)f, H5FD_MEM_FHEAP_DBLOCK, dxpl_id, (hsize_t)write_size)))
+                    HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, FAIL, "file allocation failed for fractal heap direct block")
 
-        /* Release the write buffer, if it was allocated */
-        if(write_buf != dblock->blk)
-            H5MM_xfree(write_buf);
+                /* Sanity check */
+                HDassert(!H5F_addr_eq(hdr->man_dtable.table_addr, dblock_addr));
 
-	dblock->cache_info.is_dirty = FALSE;
-    } /* end if */
+                /* Let the metadata cache know the block moved */
+                if(H5AC_move_entry((H5F_t *)f, H5AC_FHEAP_DBLOCK, hdr->man_dtable.table_addr, dblock_addr) < 0)
+                    HGOTO_ERROR(H5E_HEAP, H5E_CANTMOVE, FAIL, "unable to move direct block")
 
-    if(destroy)
-        if(H5HF_cache_dblock_dest(f, dblock) < 0)
-	    HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to destroy fractal heap direct block")
+                /* Update information about direct block's location */
+                hdr->man_dtable.table_addr = dblock_addr;
 
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* H5HF_cache_dblock_flush() */
+                /* Mark that heap header was modified */
+                if(H5HF_hdr_dirty(hdr) < 0)
+                    HGOTO_ERROR(H5E_HEAP, H5E_CANTDIRTY, FAIL, "can't mark heap header as dirty")
+            } /* end if */
+            else { /* the direct block's parent is an indirect block */
+                /* Sanity check */
+                HDassert(par_iblock);
+                HDassert(H5F_addr_eq(par_iblock->ents[par_entry].addr, addr));
 
-
-/*-------------------------------------------------------------------------
- * Function:	H5HF_cache_dblock_dest
- *
- * Purpose:	Destroys a fractal heap direct block in memory.
- *
- * Return:	Non-negative on success/Negative on failure
- *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Feb 27 2006
- *
- *-------------------------------------------------------------------------
- */
-static herr_t
-H5HF_cache_dblock_dest(H5F_t *f, H5HF_direct_t *dblock)
-{
-    herr_t      ret_value = SUCCEED;    /* Return value */
+                /* Allocate 'normal' space for the direct block */
+                if(HADDR_UNDEF == (dblock_addr = H5MF_alloc((H5F_t *)f, H5FD_MEM_FHEAP_DBLOCK, dxpl_id, (hsize_t)write_size)))
+                    HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, FAIL, "file allocation failed for fractal heap direct block")
 
-    FUNC_ENTER_NOAPI_NOINIT
+                /* Sanity check */
+                HDassert(!H5F_addr_eq(par_iblock->ents[par_entry].addr, dblock_addr));
 
-    /*
-     * Check arguments.
-     */
-    HDassert(dblock);
+                /* Let the metadata cache know the block moved */
+                if(H5AC_move_entry((H5F_t *)f, H5AC_FHEAP_DBLOCK, par_iblock->ents[par_entry].addr, dblock_addr) < 0)
+                    HGOTO_ERROR(H5E_HEAP, H5E_CANTMOVE, FAIL, "unable to move direct block")
 
-    /* If we're going to free the space on disk, the address must be valid */
-    HDassert(!dblock->cache_info.free_file_space_on_destroy || H5F_addr_defined(dblock->cache_info.addr));
+                /* Update information about direct block's location */
+                par_iblock->ents[par_entry].addr = dblock_addr;
 
-    /* Check for freeing file space for direct block */
-    if(dblock->cache_info.free_file_space_on_destroy) {
-        /* Sanity check */
-        HDassert(dblock->file_size > 0);
-
-        /* Check if the direct block is NOT currently allocated in temp. file space */
-        /* (temp. file space does not need to be freed) */
-        if(!H5F_IS_TMP_ADDR(f, dblock->cache_info.addr)) {
-            /* Release the space on disk */
-            /* (XXX: Nasty usage of internal DXPL value! -QAK) */
-            if(H5MF_xfree(f, H5FD_MEM_FHEAP_DBLOCK, H5AC_dxpl_id, dblock->cache_info.addr, dblock->file_size) < 0)
-                HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to free fractal heap direct block")
+                /* Mark that parent was modified */
+                if(H5HF_iblock_dirty(par_iblock) < 0)
+                    HGOTO_ERROR(H5E_HEAP, H5E_CANTDIRTY, FAIL, "can't mark heap header as dirty")
+            } /* end else */
         } /* end if */
+    } /* end else */
+
+    /* At this point, write_buf points to a buffer containing the image 
+     * of the direct block that is ready to copy into the image buffer,
+     * and write_size contains the length of this buffer. 
+     *
+     * Also, if image size or address has changed, the direct block's
+     * parent has been modified to reflect the change.
+     *
+     * Now, make note of the pointer and length of the above buffer for
+     * use by the serialize function.
+     */
+    dblock->write_buf = (uint8_t *)write_buf;
+    dblock->write_size = write_size;
+
+    /* finally, pass data back to the metadata cache as appropriate */
+    if(!H5F_addr_eq(addr, dblock_addr)) {
+        dblock_flags |= H5C__SERIALIZE_MOVED_FLAG;
+        *new_addr = dblock_addr;
     } /* end if */
 
-    /* Destroy fractal heap direct block */
-    if(H5HF_man_dblock_dest(dblock) < 0)
-        HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to destroy fractal heap direct block")
+    if((hdr->filter_len > 0) && (compressed_len != write_size)) {
+        dblock_flags |= H5C__SERIALIZE_COMPRESSED_FLAG;
+        *new_compressed_len = write_size;
+    } /* end if */
+
+    *flags = dblock_flags;
+
+    /* final sanity check */
+    HDassert(dblock->write_buf);
+    HDassert(dblock->write_size > 0);
 
 done:
+    /* discard the write buf if we have an error */
+    if(write_buf && (write_buf != dblock->blk) && (dblock->write_buf == NULL))
+	H5MM_xfree(write_buf);
+
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5HF_cache_dblock_dest() */
+} /* end H5HF__cache_dblock_pre_serialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HF_cache_dblock_clear
+ * Function:	H5HF__cache_dblock_serialize
  *
- * Purpose:	Mark a fractal heap direct block in memory as non-dirty.
+ * Purpose:	In principle, this function is supposed to construct the on 
+ *		disk image of the direct block, and place that image in the 
+ *		image buffer provided by the metadata cache.
  *
- * Return:	Non-negative on success/Negative on failure
+ *		However, since there are cases in which the pre_serialize 
+ *		function has to construct the on disk image to determine its size 
+ *		and address, this function simply copies the image prepared by
+ *		the pre-serialize function into the supplied image buffer, and 
+ *		discards a buffer if necessary.
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Feb 27 2006
+ * Return:	Success:	SUCCEED
+ *		Failure:	FAIL
+ *
+ * Programmer:	John Mainzer
+ *		6/21/14
  *
  *-------------------------------------------------------------------------
  */
-static herr_t
-H5HF_cache_dblock_clear(H5F_t *f, H5HF_direct_t *dblock, hbool_t destroy)
+static herr_t 
+H5HF__cache_dblock_serialize(const H5F_t *f, void *image, size_t len,
+    void *_thing)
 {
-    herr_t ret_value = SUCCEED;         /* Return value */
+    H5HF_direct_t       *dblock = (H5HF_direct_t *)_thing;      /* Direct block info */
+    herr_t               ret_value = SUCCEED;    /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC_NOERR
 
-    /*
-     * Check arguments.
-     */
+    /* Sanity checks */
+    HDassert(f);
+    HDassert(image);
+    HDassert(len > 0);
     HDassert(dblock);
+    HDassert(dblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(dblock->cache_info.type == H5AC_FHEAP_DBLOCK);
+    HDassert((dblock->blk != dblock->write_buf) || (dblock->cache_info.size == dblock->size));
+    HDassert(dblock->write_buf);
+    HDassert(dblock->write_size > 0);
+    HDassert((dblock->blk != dblock->write_buf) || (dblock->write_size == dblock->size));
+    HDassert(dblock->write_size == len);
+
+    /* Copy the image from *(dblock->write_buf) to *image */
+    HDmemcpy(image, dblock->write_buf, dblock->write_size);
+
+    /* Free *(dblock->write_buf) if it was allocated by the 
+     * pre-serialize function 
+     */
+    if(dblock->write_buf != dblock->blk)
+        H5MM_xfree(dblock->write_buf);
 
-    /* Reset the dirty flag.  */
-    dblock->cache_info.is_dirty = FALSE;
-
-    if(destroy)
-        if(H5HF_cache_dblock_dest(f, dblock) < 0)
-	    HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to destroy fractal heap direct block")
+    /* Reset the write_buf and write_size fields */
+    dblock->write_buf = NULL;
+    dblock->write_size = 0;
 
-done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5HF_cache_dblock_clear() */
+} /* end H5HF__cache_dblock_serialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HF_cache_dblock_notify
+ * Function:	H5HF__cache_dblock_notify
  *
  * Purpose:	Setup / takedown flush dependencies as direct blocks
  *		are loaded / inserted and evicted from the metadata cache.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:	Success:	SUCCEED
+ *		Failure:	FAIL
  *
  * Programmer:	John Mainzer
- *		5/17/14
+ *		6/21/14
  *
  *-------------------------------------------------------------------------
  */
-static herr_t
-H5HF_cache_dblock_notify(H5C_notify_action_t action, H5HF_direct_t *dblock)
+static herr_t 
+H5HF__cache_dblock_notify(H5C_notify_action_t action, void *_thing)
 {
-    herr_t ret_value = SUCCEED;         /* Return value */
+    H5HF_direct_t 	*dblock = (H5HF_direct_t *)_thing;      /* Fractal heap direct block */
+    herr_t 		 ret_value = SUCCEED;         /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
-    /*
-     * Check arguments.
-     */
+    /* Sanity checks */
     HDassert(dblock);
     HDassert(dblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(dblock->cache_info.type == H5AC_FHEAP_DBLOCK);
     HDassert(dblock->hdr);
     HDassert((dblock->fd_parent) ||
              ((dblock->hdr->man_dtable.curr_root_rows == 0) && (dblock->block_off == (hsize_t)0)));
 
     switch(action) {
         case H5AC_NOTIFY_ACTION_AFTER_INSERT:
+        case H5AC_NOTIFY_ACTION_AFTER_LOAD:
             HDassert(dblock->parent == dblock->fd_parent);
             if(dblock->parent) {        /* this is a leaf dblock */
                 /* create flush dependency with parent iblock */
@@ -1964,6 +2392,10 @@ H5HF_cache_dblock_notify(H5C_notify_action_t action, H5HF_direct_t *dblock)
             } /* end else */
             break;
 
+	case H5AC_NOTIFY_ACTION_AFTER_FLUSH:
+	    /* do nothing */
+	    break;
+
         case H5AC_NOTIFY_ACTION_BEFORE_EVICT:
             HDassert((dblock->parent == dblock->fd_parent) ||
                      ((NULL == dblock->parent) && (dblock->fd_parent)));
@@ -1986,39 +2418,47 @@ H5HF_cache_dblock_notify(H5C_notify_action_t action, H5HF_direct_t *dblock)
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5HF_cache_dblock_notify() */
+} /* end H5HF__cache_dblock_notify() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HF_cache_dblock_size
+ * Function:	H5HF__cache_dblock_free_icr
  *
- * Purpose:	Compute the size in bytes of a fractal heap direct block
- *		on disk, and return it in *size_ptr.  On failure,
- *		the value of *size_ptr is undefined.
+ * Purpose:	Free the in core memory allocated to the supplied direct
+ *		block.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Note:	The metadata cache sets the object's cache_info.magic to
+ *		H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC before calling a free_icr
+ *		callback (checked in assert).
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Feb 24 2006
+ * Return:	Success:	SUCCEED
+ *		Failure:	FAIL
+ *
+ * Programmer:	John Mainzer
+ *		6/21/14
  *
  *-------------------------------------------------------------------------
  */
-static herr_t
-H5HF_cache_dblock_size(const H5F_t H5_ATTR_UNUSED *f, const H5HF_direct_t *dblock, size_t *size_ptr)
+static herr_t 
+H5HF__cache_dblock_free_icr(void *_thing)
 {
-    FUNC_ENTER_NOAPI_NOINIT_NOERR
+    H5HF_direct_t       *dblock = (H5HF_direct_t *)_thing;      /* Fractal heap direct block */
+    herr_t      	 ret_value = SUCCEED;    /* Return value */
 
-    /* check arguments */
-    HDassert(dblock);
-    HDassert(size_ptr);
+    FUNC_ENTER_STATIC
 
-    /* Set size value */
-    *size_ptr = dblock->size;
+    /* Sanity checks */
+    HDassert(dblock);
+    HDassert(dblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC);
+    HDassert(dblock->cache_info.type == H5AC_FHEAP_DBLOCK);
 
-    FUNC_LEAVE_NOAPI(SUCCEED)
-} /* H5HF_cache_dblock_size() */
+    /* Destroy fractal heap direct block */
+    if(H5HF_man_dblock_dest(dblock) < 0)
+        HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to destroy fractal heap direct block")
 
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5HF__cache_dblock_free_icr() */
 
 
 /*------------------------------------------------------------------------
@@ -2144,7 +2584,7 @@ H5HF__cache_verify_hdr_descendants_clean(H5F_t *f, hid_t dxpl_id,
                      * in this case, since we know that the entry is in cache,
                      * we can pass NULL udata.
 		     */
-                    if(NULL == (root_iblock = (H5HF_indirect_t *)H5AC_protect(f, dxpl_id, H5AC_FHEAP_IBLOCK, root_iblock_addr, NULL, H5AC_READ)))
+                    if(NULL == (root_iblock = (H5HF_indirect_t *)H5AC_protect(f, dxpl_id, H5AC_FHEAP_IBLOCK, root_iblock_addr, NULL, H5C__READ_ONLY_FLAG)))
                         HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "H5AC_protect() faild.")
                     unprotect_root_iblock = TRUE;
 		} /* end if */
@@ -2205,7 +2645,7 @@ H5HF__cache_verify_hdr_descendants_clean(H5F_t *f, hid_t dxpl_id,
                      * in this case, since we know that the entry is in cache,
                      * we can pass NULL udata.
                      */
-                    if(NULL == (iblock = (H5HF_indirect_t *)H5AC_protect(f, dxpl_id, H5AC_FHEAP_IBLOCK, root_iblock_addr, NULL, H5AC_READ)))
+                    if(NULL == (iblock = (H5HF_indirect_t *)H5AC_protect(f, dxpl_id, H5AC_FHEAP_IBLOCK, root_iblock_addr, NULL, H5C__READ_ONLY_FLAG)))
                         HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "H5AC_protect() faild.")
                     unprotect_root_iblock = TRUE;
                     HDassert(iblock == root_iblock);
@@ -2595,7 +3035,7 @@ H5HF__cache_verify_descendant_iblocks_clean(H5F_t *f, hid_t dxpl_id,
 			    /* in this case, since we know that the      */
 			    /* entry is in cache, we can pass NULL udata */
 
-			    if(NULL == (child_iblock = (H5HF_indirect_t *) H5AC_protect(f, dxpl_id, H5AC_FHEAP_IBLOCK, child_iblock_addr, NULL, H5AC_READ)))
+			    if(NULL == (child_iblock = (H5HF_indirect_t *) H5AC_protect(f, dxpl_id, H5AC_FHEAP_IBLOCK, child_iblock_addr, NULL, H5C__READ_ONLY_FLAG)))
                                 HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "H5AC_protect() faild.")
 			    unprotect_child_iblock = TRUE;
 			} /* end if */
diff --git a/src/H5HFdbg.c b/src/H5HFdbg.c
index 8620f6f..5183b67 100644
--- a/src/H5HFdbg.c
+++ b/src/H5HFdbg.c
@@ -323,7 +323,7 @@ H5HF_hdr_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE *stream, int indent,
     HDassert(fwidth >= 0);
 
     /* Load the fractal heap header */
-    if(NULL == (hdr = H5HF_hdr_protect(f, dxpl_id, addr, H5AC_READ)))
+    if(NULL == (hdr = H5HF_hdr_protect(f, dxpl_id, addr, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "unable to protect fractal heap header")
 
     /* Print the information about the heap's header */
@@ -459,13 +459,13 @@ H5HF_dblock_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE *stream,
     HDassert(block_size > 0);
 
     /* Load the fractal heap header */
-    if(NULL == (hdr = H5HF_hdr_protect(f, dxpl_id, hdr_addr, H5AC_READ)))
+    if(NULL == (hdr = H5HF_hdr_protect(f, dxpl_id, hdr_addr, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "unable to protect fractal heap header")
 
     /*
      * Load the heap direct block
      */
-    if(NULL == (dblock = H5HF_man_dblock_protect(hdr, dxpl_id, addr, block_size, NULL, 0, H5AC_READ)))
+    if(NULL == (dblock = H5HF_man_dblock_protect(hdr, dxpl_id, addr, block_size, NULL, 0, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_HEAP, H5E_CANTLOAD, FAIL, "unable to load fractal heap direct block")
 
     /* Print opening message */
@@ -716,13 +716,13 @@ H5HF_iblock_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE *stream,
     HDassert(nrows > 0);
 
     /* Load the fractal heap header */
-    if(NULL == (hdr = H5HF_hdr_protect(f, dxpl_id, hdr_addr, H5AC_READ)))
+    if(NULL == (hdr = H5HF_hdr_protect(f, dxpl_id, hdr_addr, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "unable to protect fractal heap header")
 
     /*
      * Load the heap indirect block
      */
-    if(NULL == (iblock = H5HF_man_iblock_protect(hdr, dxpl_id, addr, nrows, NULL, 0, FALSE, H5AC_READ, &did_protect)))
+    if(NULL == (iblock = H5HF_man_iblock_protect(hdr, dxpl_id, addr, nrows, NULL, 0, FALSE, H5AC__READ_ONLY_FLAG, &did_protect)))
 	HGOTO_ERROR(H5E_HEAP, H5E_CANTLOAD, FAIL, "unable to load fractal heap indirect block")
 
     /* Print the information about the heap's indirect block */
@@ -825,7 +825,7 @@ H5HF_sects_debug(H5F_t *f, hid_t dxpl_id, haddr_t fh_addr,
     HDassert(fwidth >= 0);
 
     /* Load the fractal heap header */
-    if(NULL == (hdr = H5HF_hdr_protect(f, dxpl_id, fh_addr, H5AC_READ)))
+    if(NULL == (hdr = H5HF_hdr_protect(f, dxpl_id, fh_addr, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "unable to protect fractal heap header")
 
     /* Initialize the free space information for the heap */
diff --git a/src/H5HFdblock.c b/src/H5HFdblock.c
index 9a8da4a..5dd5b0c 100644
--- a/src/H5HFdblock.c
+++ b/src/H5HFdblock.c
@@ -149,6 +149,9 @@ H5HF_man_dblock_create(hid_t dxpl_id, H5HF_hdr_t *hdr, H5HF_indirect_t *par_iblo
 HDmemset(dblock->blk, 0, dblock->size);
 #endif /* H5_CLEAR_MEMORY */
 
+    dblock->write_buf = NULL;
+    dblock->write_size = 0;
+
     /* Allocate [temporary] space for the direct block on disk */
     if(H5F_USE_TMP_SPACE(hdr->f)) {
         if(HADDR_UNDEF == (dblock_addr = H5MF_alloc_tmp(hdr->f, (hsize_t)dblock->size)))
@@ -308,9 +311,13 @@ H5HF_man_dblock_destroy(H5HF_hdr_t *hdr, hid_t dxpl_id, H5HF_direct_t *dblock,
         } /* end if */
     } /* end else */
 
-    /* Indicate that the indirect block should be deleted & file space freed */
+    /* Indicate that the indirect block should be deleted */
     dblock->file_size = dblock_size;
-    cache_flags |= H5AC__DIRTIED_FLAG | H5AC__DELETED_FLAG | H5AC__FREE_FILE_SPACE_FLAG;
+    cache_flags |= H5AC__DIRTIED_FLAG | H5AC__DELETED_FLAG;
+
+    /* If the dblock is in real file space, also tell the cache to free its file space */
+    if (!H5F_IS_TMP_ADDR(hdr->f, dblock_addr))
+        cache_flags |= H5AC__FREE_FILE_SPACE_FLAG;
 
 done:
     /* Unprotect the indirect block, with appropriate flags */
@@ -436,7 +443,7 @@ done:
 H5HF_direct_t *
 H5HF_man_dblock_protect(H5HF_hdr_t *hdr, hid_t dxpl_id, haddr_t dblock_addr,
     size_t dblock_size, H5HF_indirect_t *par_iblock, unsigned par_entry,
-    H5AC_protect_t rw)
+    unsigned flags)
 {
     H5HF_direct_t *dblock;      /* Direct block from cache */
     H5HF_dblock_cache_ud_t udata;	/* parent and other infor for deserializing direct block */
@@ -451,6 +458,9 @@ H5HF_man_dblock_protect(H5HF_hdr_t *hdr, hid_t dxpl_id, haddr_t dblock_addr,
     HDassert(H5F_addr_defined(dblock_addr));
     HDassert(dblock_size > 0);
 
+    /* only H5AC__READ_ONLY_FLAG may appear in flags */
+    HDassert((flags & (~H5AC__READ_ONLY_FLAG)) == 0);
+
     /* Set up parent info */
     udata.par_info.hdr = hdr;
     udata.par_info.iblock = par_iblock;
@@ -485,7 +495,7 @@ H5HF_man_dblock_protect(H5HF_hdr_t *hdr, hid_t dxpl_id, haddr_t dblock_addr,
     } /* end else */
 
     /* Protect the direct block */
-    if(NULL == (dblock = (H5HF_direct_t *)H5AC_protect(hdr->f, dxpl_id, H5AC_FHEAP_DBLOCK, dblock_addr, &udata, rw)))
+    if(NULL == (dblock = (H5HF_direct_t *)H5AC_protect(hdr->f, dxpl_id, H5AC_FHEAP_DBLOCK, dblock_addr, &udata, flags)))
         HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, NULL, "unable to protect fractal heap direct block")
 
     /* Set the return value */
@@ -512,7 +522,7 @@ done:
 herr_t
 H5HF_man_dblock_locate(H5HF_hdr_t *hdr, hid_t dxpl_id, hsize_t obj_off,
     H5HF_indirect_t **ret_iblock, unsigned *ret_entry, hbool_t *ret_did_protect,
-    H5AC_protect_t rw)
+    unsigned flags)
 {
     haddr_t iblock_addr;            /* Indirect block's address */
     H5HF_indirect_t *iblock;        /* Pointer to indirect block */
@@ -531,6 +541,9 @@ H5HF_man_dblock_locate(H5HF_hdr_t *hdr, hid_t dxpl_id, hsize_t obj_off,
     HDassert(ret_iblock);
     HDassert(ret_did_protect);
 
+    /* only H5AC__READ_ONLY_FLAG may appear in flags */
+    HDassert((flags & (~H5AC__READ_ONLY_FLAG)) == 0);
+
     /* Look up row & column for object */
     if(H5HF_dtable_lookup(&hdr->man_dtable, obj_off, &row, &col) < 0)
         HGOTO_ERROR(H5E_HEAP, H5E_CANTCOMPUTE, FAIL, "can't compute row & column of object")
@@ -539,7 +552,7 @@ H5HF_man_dblock_locate(H5HF_hdr_t *hdr, hid_t dxpl_id, hsize_t obj_off,
     iblock_addr = hdr->man_dtable.table_addr;
 
     /* Lock root indirect block */
-    if(NULL == (iblock = H5HF_man_iblock_protect(hdr, dxpl_id, iblock_addr, hdr->man_dtable.curr_root_rows, NULL, 0, FALSE, rw, &did_protect)))
+    if(NULL == (iblock = H5HF_man_iblock_protect(hdr, dxpl_id, iblock_addr, hdr->man_dtable.curr_root_rows, NULL, 0, FALSE, flags, &did_protect)))
         HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "unable to protect fractal heap indirect block")
 
     /* Check for indirect block row */
@@ -569,7 +582,7 @@ H5HF_man_dblock_locate(H5HF_hdr_t *hdr, hid_t dxpl_id, hsize_t obj_off,
         } /* end if */
 
         /* Lock child indirect block */
-        if(NULL == (new_iblock = H5HF_man_iblock_protect(hdr, dxpl_id, iblock_addr, nrows, iblock, entry, FALSE, rw, &new_did_protect)))
+        if(NULL == (new_iblock = H5HF_man_iblock_protect(hdr, dxpl_id, iblock_addr, nrows, iblock, entry, FALSE, flags, &new_did_protect)))
             HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "unable to protect fractal heap indirect block")
 
         /* Release the current indirect block */
diff --git a/src/H5HFhdr.c b/src/H5HFhdr.c
index cf8da23..340940f 100644
--- a/src/H5HFhdr.c
+++ b/src/H5HFhdr.c
@@ -529,7 +529,7 @@ done:
  *-------------------------------------------------------------------------
  */
 H5HF_hdr_t *
-H5HF_hdr_protect(H5F_t *f, hid_t dxpl_id, haddr_t addr, H5AC_protect_t rw)
+H5HF_hdr_protect(H5F_t *f, hid_t dxpl_id, haddr_t addr, unsigned flags)
 {
     H5HF_hdr_cache_ud_t cache_udata;    /* User-data for callback */
     H5HF_hdr_t *hdr;                    /* Fractal heap header */
@@ -541,12 +541,15 @@ H5HF_hdr_protect(H5F_t *f, hid_t dxpl_id, haddr_t addr, H5AC_protect_t rw)
     HDassert(f);
     HDassert(H5F_addr_defined(addr));
 
+    /* only H5AC__READ_ONLY_FLAG may appear in flags */
+    HDassert((flags & (unsigned)(~H5AC__READ_ONLY_FLAG)) == 0);
+
     /* Set up userdata for protect call */
     cache_udata.f = f;
     cache_udata.dxpl_id = dxpl_id;
 
     /* Lock the heap header into memory */
-    if(NULL == (hdr = (H5HF_hdr_t *)H5AC_protect(f, dxpl_id, H5AC_FHEAP_HDR, addr, &cache_udata, rw)))
+    if(NULL == (hdr = (H5HF_hdr_t *)H5AC_protect(f, dxpl_id, H5AC_FHEAP_HDR, addr, &cache_udata, flags)))
         HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, NULL, "unable to protect fractal heap header")
 
     /* Set the header's address */
@@ -1109,7 +1112,7 @@ H5HF_hdr_update_iter(H5HF_hdr_t *hdr, hid_t dxpl_id, size_t min_dblock_size)
                         HGOTO_ERROR(H5E_HEAP, H5E_CANTALLOC, FAIL, "can't allocate fractal heap indirect block")
 
                     /* Lock new indirect block */
-                    if(NULL == (new_iblock = H5HF_man_iblock_protect(hdr, dxpl_id, new_iblock_addr, child_nrows, iblock, next_entry, FALSE, H5AC_WRITE, &did_protect)))
+                    if(NULL == (new_iblock = H5HF_man_iblock_protect(hdr, dxpl_id, new_iblock_addr, child_nrows, iblock, next_entry, FALSE, H5AC__NO_FLAGS_SET, &did_protect)))
                         HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "unable to protect fractal heap indirect block")
 
                     /* Move iterator down one level (pins indirect block) */
@@ -1303,7 +1306,7 @@ H5HF_hdr_reverse_iter(H5HF_hdr_t *hdr, hid_t dxpl_id, haddr_t dblock_addr)
                 child_nrows = H5HF_dtable_size_to_rows(&hdr->man_dtable, hdr->man_dtable.row_block_size[row]);
 
                 /* Lock child indirect block */
-                if(NULL == (child_iblock = H5HF_man_iblock_protect(hdr, dxpl_id, iblock->ents[curr_entry].addr, child_nrows, iblock, curr_entry, FALSE, H5AC_WRITE, &did_protect)))
+                if(NULL == (child_iblock = H5HF_man_iblock_protect(hdr, dxpl_id, iblock->ents[curr_entry].addr, child_nrows, iblock, curr_entry, FALSE, H5AC__NO_FLAGS_SET, &did_protect)))
                     HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "unable to protect fractal heap indirect block")
 
                 /* Set the current location of the iterator */
diff --git a/src/H5HFiblock.c b/src/H5HFiblock.c
index 4473803..547aaf0 100644
--- a/src/H5HFiblock.c
+++ b/src/H5HFiblock.c
@@ -330,8 +330,15 @@ H5HF_iblock_decr(H5HF_indirect_t *iblock)
 
 	/* Check for expunging the indirect block from the metadata cache */
 	if(expunge_iblock) {
-            /* Evict the indirect block from the metadata cache */
-            if(H5AC_expunge_entry(hdr->f, H5AC_dxpl_id, H5AC_FHEAP_IBLOCK, iblock_addr, H5AC__FREE_FILE_SPACE_FLAG) < 0)
+            unsigned cache_flags = H5AC__NO_FLAGS_SET;
+
+            /* if the indirect block is in real file space, tell 
+             * the cache to free its file space.
+             */
+            if (!H5F_IS_TMP_ADDR(hdr->f, iblock_addr))
+                cache_flags |= H5AC__FREE_FILE_SPACE_FLAG;
+
+            if(H5AC_expunge_entry(hdr->f, H5AC_dxpl_id, H5AC_FHEAP_IBLOCK, iblock_addr, cache_flags) < 0)
                 HGOTO_ERROR(H5E_HEAP, H5E_CANTREMOVE, FAIL, "unable to remove indirect block from cache")
         } /* end if */
     } /* end if */
@@ -424,7 +431,7 @@ H5HF_man_iblock_root_create(H5HF_hdr_t *hdr, hid_t dxpl_id, size_t min_dblock_si
     /* Move current direct block (used as root) into new indirect block */
 
     /* Lock new indirect block */
-    if(NULL == (iblock = H5HF_man_iblock_protect(hdr, dxpl_id, iblock_addr, nrows, NULL, 0, FALSE, H5AC_WRITE, &did_protect)))
+    if(NULL == (iblock = H5HF_man_iblock_protect(hdr, dxpl_id, iblock_addr, nrows, NULL, 0, FALSE, H5AC__NO_FLAGS_SET, &did_protect)))
         HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "unable to protect fractal heap indirect block")
 
     /* Check if there's already a direct block as root) */
@@ -433,7 +440,7 @@ H5HF_man_iblock_root_create(H5HF_hdr_t *hdr, hid_t dxpl_id, size_t min_dblock_si
         H5HF_direct_t *dblock;          /* Pointer to direct block to query */
 
         /* Lock first (root) direct block */
-        if(NULL == (dblock = H5HF_man_dblock_protect(hdr, dxpl_id, hdr->man_dtable.table_addr, hdr->man_dtable.cparam.start_block_size, NULL, 0, H5AC_WRITE)))
+        if(NULL == (dblock = H5HF_man_dblock_protect(hdr, dxpl_id, hdr->man_dtable.table_addr, hdr->man_dtable.cparam.start_block_size, NULL, 0, H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "unable to protect fractal heap direct block")
 
         /* Attach direct block to new root indirect block */
@@ -879,7 +886,7 @@ H5HF_man_iblock_root_revert(H5HF_indirect_t *root_iblock, hid_t dxpl_id)
     dblock_size = hdr->man_dtable.cparam.start_block_size;
 
     /* Get pointer to last direct block */
-    if(NULL == (dblock = H5HF_man_dblock_protect(hdr, dxpl_id, dblock_addr, dblock_size, root_iblock, 0, H5AC_WRITE)))
+    if(NULL == (dblock = H5HF_man_dblock_protect(hdr, dxpl_id, dblock_addr, dblock_size, root_iblock, 0, H5AC__NO_FLAGS_SET)))
         HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "unable to protect fractal heap direct block")
     HDassert(dblock->parent == root_iblock);
     HDassert(dblock->par_entry == 0);
@@ -1159,7 +1166,7 @@ done:
 H5HF_indirect_t *
 H5HF_man_iblock_protect(H5HF_hdr_t *hdr, hid_t dxpl_id, haddr_t iblock_addr,
     unsigned iblock_nrows, H5HF_indirect_t *par_iblock, unsigned par_entry,
-    hbool_t must_protect, H5AC_protect_t rw, hbool_t *did_protect)
+    hbool_t must_protect, unsigned flags, hbool_t *did_protect)
 {
     H5HF_parent_t par_info;             /* Parent info for loading block */
     H5HF_indirect_t *iblock = NULL;     /* Indirect block from cache */
@@ -1176,6 +1183,9 @@ H5HF_man_iblock_protect(H5HF_hdr_t *hdr, hid_t dxpl_id, haddr_t iblock_addr,
     HDassert(iblock_nrows > 0);
     HDassert(did_protect);
 
+    /* only H5AC__READ_ONLY_FLAG may appear in flags */
+    HDassert((flags & (unsigned)(~H5AC__READ_ONLY_FLAG)) == 0);
+
     /* Check if we are allowed to use existing pinned iblock pointer */
     if(!must_protect) {
         /* Check for this block already being pinned */
@@ -1235,7 +1245,7 @@ H5HF_man_iblock_protect(H5HF_hdr_t *hdr, hid_t dxpl_id, haddr_t iblock_addr,
         cache_udata.nrows = &iblock_nrows;
 
         /* Protect the indirect block */
-        if(NULL == (iblock = (H5HF_indirect_t *)H5AC_protect(hdr->f, dxpl_id, H5AC_FHEAP_IBLOCK, iblock_addr, &cache_udata, rw)))
+        if(NULL == (iblock = (H5HF_indirect_t *)H5AC_protect(hdr->f, dxpl_id, H5AC_FHEAP_IBLOCK, iblock_addr, &cache_udata, flags)))
             HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, NULL, "unable to protect fractal heap indirect block")
 
         /* Set the indirect block's address */
@@ -1579,7 +1589,7 @@ H5HF_man_iblock_delete(H5HF_hdr_t *hdr, hid_t dxpl_id, haddr_t iblock_addr,
     HDassert(iblock_nrows > 0);
 
     /* Lock indirect block */
-    if(NULL == (iblock = H5HF_man_iblock_protect(hdr, dxpl_id, iblock_addr, iblock_nrows, par_iblock, par_entry, TRUE, H5AC_WRITE, &did_protect)))
+    if(NULL == (iblock = H5HF_man_iblock_protect(hdr, dxpl_id, iblock_addr, iblock_nrows, par_iblock, par_entry, TRUE, H5AC__NO_FLAGS_SET, &did_protect)))
         HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "unable to protect fractal heap indirect block")
     HDassert(iblock->nchildren > 0);
     HDassert(did_protect == TRUE);
@@ -1637,8 +1647,14 @@ H5HF_man_iblock_delete(H5HF_hdr_t *hdr, hid_t dxpl_id, haddr_t iblock_addr,
 }
 #endif /* NDEBUG */
 
-    /* Indicate that the indirect block should be deleted & file space freed */
-    cache_flags |= H5AC__DIRTIED_FLAG | H5AC__DELETED_FLAG | H5AC__FREE_FILE_SPACE_FLAG;
+    /* Indicate that the indirect block should be deleted  */
+    cache_flags |= H5AC__DIRTIED_FLAG | H5AC__DELETED_FLAG;
+
+    /* If the indirect block is in real file space, tell
+     * the cache to free its file space as well.
+     */
+    if (!H5F_IS_TMP_ADDR(hdr->f, iblock_addr))
+        cache_flags |= H5AC__FREE_FILE_SPACE_FLAG;
 
 done:
     /* Unprotect the indirect block, with appropriate flags */
@@ -1680,7 +1696,7 @@ H5HF_man_iblock_size(H5F_t *f, hid_t dxpl_id, H5HF_hdr_t *hdr, haddr_t iblock_ad
     HDassert(heap_size);
 
     /* Protect the indirect block */
-    if(NULL == (iblock = H5HF_man_iblock_protect(hdr, dxpl_id, iblock_addr, nrows, par_iblock, par_entry, FALSE, H5AC_READ, &did_protect)))
+    if(NULL == (iblock = H5HF_man_iblock_protect(hdr, dxpl_id, iblock_addr, nrows, par_iblock, par_entry, FALSE, H5AC__READ_ONLY_FLAG, &did_protect)))
         HGOTO_ERROR(H5E_HEAP, H5E_CANTLOAD, FAIL, "unable to load fractal heap indirect block")
 
     /* Accumulate size of this indirect block */
diff --git a/src/H5HFiter.c b/src/H5HFiter.c
index 137d0ee..262a9ee 100644
--- a/src/H5HFiter.c
+++ b/src/H5HFiter.c
@@ -217,7 +217,7 @@ H5HF_man_iter_start_offset(H5HF_hdr_t *hdr, hid_t dxpl_id,
         } /* end else */
 
         /* Load indirect block for this context location */
-        if(NULL == (iblock = H5HF_man_iblock_protect(hdr, dxpl_id, iblock_addr, iblock_nrows, iblock_parent, iblock_par_entry, FALSE, H5AC_WRITE, &did_protect)))
+        if(NULL == (iblock = H5HF_man_iblock_protect(hdr, dxpl_id, iblock_addr, iblock_nrows, iblock_parent, iblock_par_entry, FALSE, H5AC__NO_FLAGS_SET, &did_protect)))
             HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "unable to protect fractal heap indirect block")
 
         /* Make indirect block the context for the current location */
diff --git a/src/H5HFman.c b/src/H5HFman.c
index 58dab10..5f95a91 100644
--- a/src/H5HFman.c
+++ b/src/H5HFman.c
@@ -161,7 +161,7 @@ H5HF_man_insert(H5HF_hdr_t *hdr, hid_t dxpl_id, size_t obj_size, const void *obj
         HGOTO_ERROR(H5E_HEAP, H5E_CANTGET, FAIL, "can't retrieve direct block information")
 
     /* Lock direct block */
-    if(NULL == (dblock = H5HF_man_dblock_protect(hdr, dxpl_id, dblock_addr, dblock_size, sec_node->u.single.parent, sec_node->u.single.par_entry, H5AC_WRITE)))
+    if(NULL == (dblock = H5HF_man_dblock_protect(hdr, dxpl_id, dblock_addr, dblock_size, sec_node->u.single.parent, sec_node->u.single.par_entry, H5AC__NO_FLAGS_SET)))
         HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "unable to load fractal heap direct block")
 
     /* Insert object into block */
@@ -274,7 +274,11 @@ H5HF_man_op_real(H5HF_hdr_t *hdr, hid_t dxpl_id, const uint8_t *id,
     H5HF_operator_t op, void *op_data, unsigned op_flags)
 {
     H5HF_direct_t *dblock = NULL;       /* Pointer to direct block to query */
-    H5AC_protect_t dblock_access;       /* Access method for direct block */
+    unsigned dblock_access_flags;       /* Access method for direct block */
+                                        /* must equal either 
+                                         * H5AC__NO_FLAGS_SET or 
+                                         * H5AC__READ_ONLY_FLAG
+                                         */
     haddr_t dblock_addr;                /* Direct block address */
     size_t dblock_size;                 /* Direct block size */
     unsigned dblock_cache_flags;        /* Flags for unprotecting direct block */
@@ -298,11 +302,11 @@ H5HF_man_op_real(H5HF_hdr_t *hdr, hid_t dxpl_id, const uint8_t *id,
         /* Check pipeline */
         H5HF_MAN_WRITE_CHECK_PLINE(hdr)
 
-        dblock_access = H5AC_WRITE;
+        dblock_access_flags = H5AC__NO_FLAGS_SET;
         dblock_cache_flags = H5AC__DIRTIED_FLAG;
     } /* end if */
     else {
-        dblock_access = H5AC_READ;
+        dblock_access_flags = H5AC__READ_ONLY_FLAG;
         dblock_cache_flags = H5AC__NO_FLAGS_SET;
     } /* end else */
 
@@ -332,7 +336,7 @@ H5HF_man_op_real(H5HF_hdr_t *hdr, hid_t dxpl_id, const uint8_t *id,
         dblock_size = hdr->man_dtable.cparam.start_block_size;
 
         /* Lock direct block */
-        if(NULL == (dblock = H5HF_man_dblock_protect(hdr, dxpl_id, dblock_addr, dblock_size, NULL, 0, dblock_access)))
+        if(NULL == (dblock = H5HF_man_dblock_protect(hdr, dxpl_id, dblock_addr, dblock_size, NULL, 0, dblock_access_flags)))
             HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "unable to protect fractal heap direct block")
     } /* end if */
     else {
@@ -341,7 +345,7 @@ H5HF_man_op_real(H5HF_hdr_t *hdr, hid_t dxpl_id, const uint8_t *id,
         unsigned entry;                 /* Entry of block */
 
         /* Look up indirect block containing direct block */
-        if(H5HF_man_dblock_locate(hdr, dxpl_id, obj_off, &iblock, &entry, &did_protect, H5AC_READ) < 0)
+        if(H5HF_man_dblock_locate(hdr, dxpl_id, obj_off, &iblock, &entry, &did_protect, H5AC__READ_ONLY_FLAG) < 0)
             HGOTO_ERROR(H5E_HEAP, H5E_CANTCOMPUTE, FAIL, "can't compute row & column of section")
 
         /* Set direct block info */
@@ -359,7 +363,7 @@ H5HF_man_op_real(H5HF_hdr_t *hdr, hid_t dxpl_id, const uint8_t *id,
         } /* end if */
 
         /* Lock direct block */
-        if(NULL == (dblock = H5HF_man_dblock_protect(hdr, dxpl_id, dblock_addr, dblock_size, iblock, entry, dblock_access))) {
+        if(NULL == (dblock = H5HF_man_dblock_protect(hdr, dxpl_id, dblock_addr, dblock_size, iblock, entry, dblock_access_flags))) {
             /* Unlock indirect block */
             if(H5HF_man_iblock_unprotect(iblock, dxpl_id, H5AC__NO_FLAGS_SET, did_protect) < 0)
                 HGOTO_ERROR(H5E_HEAP, H5E_CANTUNPROTECT, FAIL, "unable to release fractal heap indirect block")
@@ -578,7 +582,7 @@ H5HF_man_remove(H5HF_hdr_t *hdr, hid_t dxpl_id, const uint8_t *id)
     } /* end if */
     else {
         /* Look up indirect block containing direct block */
-        if(H5HF_man_dblock_locate(hdr, dxpl_id, obj_off, &iblock, &dblock_entry, &did_protect, H5AC_WRITE) < 0)
+        if(H5HF_man_dblock_locate(hdr, dxpl_id, obj_off, &iblock, &dblock_entry, &did_protect, H5AC__NO_FLAGS_SET) < 0)
             HGOTO_ERROR(H5E_HEAP, H5E_CANTCOMPUTE, FAIL, "can't compute row & column of section")
 
         /* Check for offset of invalid direct block */
diff --git a/src/H5HFpkg.h b/src/H5HFpkg.h
index 63c1a3e..4655d83 100644
--- a/src/H5HFpkg.h
+++ b/src/H5HFpkg.h
@@ -341,7 +341,7 @@ typedef struct H5HF_hdr_t {
     size_t      rc;             /* Reference count of heap's components using heap header */
     haddr_t     heap_addr;      /* Address of heap header in the file */
     size_t      heap_size;      /* Size of heap header in the file */
-    H5AC_protect_t mode;        /* Access mode for heap */
+    unsigned    mode;           /* Access mode for heap */
     H5F_t      *f;              /* Pointer to file for heap */
     size_t      file_rc;        /* Reference count of files using heap header */
     hbool_t     pending_delete; /* Heap is pending deletion */
@@ -424,6 +424,31 @@ typedef struct H5HF_direct_t {
     size_t      size;           /* Size of direct block                       */
     hsize_t     file_size;      /* Size of direct block in file (only valid when block's space is being freed) */
     uint8_t     *blk;           /* Pointer to buffer containing block data    */
+    uint8_t	*write_buf;	/* Pointer to buffer containing the block data */
+                                /* in form ready to copy to the metadata       */
+                                /* cache's image buffer.                       */
+                                /*                                             */
+                                /* This field is used by                       */
+                                /* H5HF_cache_dblock_pre_serialize() to pass   */
+                                /* the serialized image of the direct block to */
+                                /* H5HF_cache_dblock_serialize().  It should   */
+                                /* NULL at all other times.                    */
+                                /*                                             */
+                                /* If I/O filters are enabled, the pre-        */
+                                /* the pre-serialize function will allocate    */
+                                /* a buffer, copy the filtered version of the  */
+                                /* direct block image into it, and place the   */
+                                /* base address of the buffer in this field.   */
+                                /* The serialize function must discard this    */
+                                /* buffer after it copies the contents into    */
+                                /* the image buffer provided by the metadata   */
+                                /* cache.                                      */
+                                /*                                             */
+                                /* If I/O filters are not enabled, the         */
+                                /* write_buf field is simply set equal to the  */
+                                /* blk field by the pre-serialize function,    */
+                                /* and back to NULL by the serialize function. */
+    size_t	write_size;     /* size of the buffer pointed to by write_buf. */
 
     /* Stored values */
     hsize_t     block_off;      /* Offset of the block within the heap's address space */
@@ -597,7 +622,7 @@ H5_DLL hsize_t H5HF_dtable_span_size(const H5HF_dtable_t *dtable, unsigned start
 H5_DLL H5HF_hdr_t * H5HF_hdr_alloc(H5F_t *f);
 H5_DLL haddr_t H5HF_hdr_create(H5F_t *f, hid_t dxpl_id, const H5HF_create_t *cparam);
 H5_DLL H5HF_hdr_t *H5HF_hdr_protect(H5F_t *f, hid_t dxpl_id, haddr_t addr,
-    H5AC_protect_t rw);
+    unsigned flags);
 H5_DLL herr_t H5HF_hdr_finish_init_phase1(H5HF_hdr_t *hdr);
 H5_DLL herr_t H5HF_hdr_finish_init_phase2(H5HF_hdr_t *hdr);
 H5_DLL herr_t H5HF_hdr_finish_init(H5HF_hdr_t *hdr);
@@ -638,7 +663,7 @@ H5_DLL herr_t H5HF_man_iblock_create(H5HF_hdr_t *hdr, hid_t dxpl_id,
 H5_DLL H5HF_indirect_t *H5HF_man_iblock_protect(H5HF_hdr_t *hdr, hid_t dxpl_id,
     haddr_t iblock_addr, unsigned iblock_nrows,
     H5HF_indirect_t *par_iblock, unsigned par_entry, hbool_t must_protect,
-    H5AC_protect_t rw, hbool_t *did_protect);
+    unsigned flags, hbool_t *did_protect);
 H5_DLL herr_t H5HF_man_iblock_unprotect(H5HF_indirect_t *iblock, hid_t dxpl_id,
     unsigned cache_flags, hbool_t did_protect);
 H5_DLL herr_t H5HF_man_iblock_attach(H5HF_indirect_t *iblock, unsigned entry,
@@ -664,10 +689,10 @@ H5_DLL herr_t H5HF_man_dblock_destroy(H5HF_hdr_t *hdr, hid_t dxpl_id,
 H5_DLL H5HF_direct_t *H5HF_man_dblock_protect(H5HF_hdr_t *hdr, hid_t dxpl_id,
     haddr_t dblock_addr, size_t dblock_size,
     H5HF_indirect_t *par_iblock, unsigned par_entry,
-    H5AC_protect_t rw);
+    unsigned flags);
 H5_DLL herr_t H5HF_man_dblock_locate(H5HF_hdr_t *hdr, hid_t dxpl_id,
     hsize_t obj_off, H5HF_indirect_t **par_iblock,
-    unsigned *par_entry, hbool_t *par_did_protect, H5AC_protect_t rw);
+    unsigned *par_entry, hbool_t *par_did_protect, unsigned flags);
 H5_DLL herr_t H5HF_man_dblock_delete(H5F_t *f, hid_t dxpl_id, haddr_t dblock_addr,
     hsize_t dblock_size);
 H5_DLL herr_t H5HF_man_dblock_dest(H5HF_direct_t *dblock);
diff --git a/src/H5HFsection.c b/src/H5HFsection.c
index 01a7b4a..c997119 100644
--- a/src/H5HFsection.c
+++ b/src/H5HFsection.c
@@ -555,7 +555,7 @@ H5HF_sect_single_locate_parent(H5HF_hdr_t *hdr, hid_t dxpl_id, hbool_t refresh,
     HDassert(sect);
 
     /* Look up indirect block containing direct blocks for range */
-    if(H5HF_man_dblock_locate(hdr, dxpl_id, sect->sect_info.addr, &sec_iblock, &sec_entry, &did_protect, H5AC_READ) < 0)
+    if(H5HF_man_dblock_locate(hdr, dxpl_id, sect->sect_info.addr, &sec_iblock, &sec_entry, &did_protect, H5AC__READ_ONLY_FLAG) < 0)
         HGOTO_ERROR(H5E_HEAP, H5E_CANTCOMPUTE, FAIL, "can't compute row & column of section")
 
     /* Increment reference count on indirect block that free section is in */
@@ -776,7 +776,7 @@ H5HF_sect_single_full_dblock(H5HF_hdr_t *hdr, hid_t dxpl_id,
             hdr->man_dtable.curr_root_rows > 0) {
         H5HF_direct_t *dblock;          /* Pointer to direct block for section */
 
-        if(NULL == (dblock = H5HF_man_dblock_protect(hdr, dxpl_id, dblock_addr, dblock_size, sect->u.single.parent, sect->u.single.par_entry, H5AC_WRITE)))
+        if(NULL == (dblock = H5HF_man_dblock_protect(hdr, dxpl_id, dblock_addr, dblock_size, sect->u.single.parent, sect->u.single.par_entry, H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "unable to load fractal heap direct block")
         HDassert(H5F_addr_eq(dblock->block_off + dblock_overhead, sect->sect_info.addr));
 
@@ -1094,7 +1094,7 @@ H5HF_sect_single_shrink(H5FS_section_info_t **_sect, void H5_ATTR_UNUSED *_udata
     /* (should be a root direct block) */
     HDassert(dblock_addr == hdr->man_dtable.table_addr);
     if(NULL == (dblock = H5HF_man_dblock_protect(hdr, dxpl_id, dblock_addr,
-            dblock_size, (*sect)->u.single.parent, (*sect)->u.single.par_entry, H5AC_WRITE)))
+            dblock_size, (*sect)->u.single.parent, (*sect)->u.single.par_entry, H5AC__NO_FLAGS_SET)))
         HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "unable to load fractal heap direct block")
     HDassert(H5F_addr_eq(dblock->block_off + dblock_size, (*sect)->sect_info.addr + (*sect)->sect_info.size));
 
@@ -1221,7 +1221,7 @@ H5HF_sect_single_valid(const H5FS_section_class_t H5_ATTR_UNUSED *cls, const H5F
                 H5HF_direct_t *dblock;      /* Direct block for section */
 
                 /* Protect the direct block for the section */
-                dblock = H5HF_man_dblock_protect(iblock->hdr, H5AC_dxpl_id, dblock_addr, dblock_size, iblock, sect->u.single.par_entry, H5AC_READ);
+                dblock = H5HF_man_dblock_protect(iblock->hdr, H5AC_dxpl_id, dblock_addr, dblock_size, iblock, sect->u.single.par_entry, H5AC__READ_ONLY_FLAG);
                 HDassert(dblock);
 
                 /* Sanity check settings for section */
@@ -2536,7 +2536,7 @@ H5HF_sect_indirect_init_rows(H5HF_hdr_t *hdr, hid_t dxpl_id,
 
                     /* If the child indirect block's address is defined, protect it */
                     if(H5F_addr_defined(child_iblock_addr)) {
-                        if(NULL == (child_iblock = H5HF_man_iblock_protect(hdr, dxpl_id, child_iblock_addr, child_nrows, sect->u.indirect.u.iblock, curr_entry, FALSE, H5AC_WRITE, &did_protect)))
+                        if(NULL == (child_iblock = H5HF_man_iblock_protect(hdr, dxpl_id, child_iblock_addr, child_nrows, sect->u.indirect.u.iblock, curr_entry, FALSE, H5AC__NO_FLAGS_SET, &did_protect)))
                             HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "unable to protect fractal heap indirect block")
                     } /* end if */
                     else
@@ -2771,7 +2771,7 @@ H5HF_sect_indirect_revive_row(H5HF_hdr_t *hdr, hid_t dxpl_id, H5HF_free_section_
     HDassert(sect->sect_info.state == H5FS_SECT_SERIALIZED);
 
     /* Look up indirect block containing indirect blocks for section */
-    if(H5HF_man_dblock_locate(hdr, dxpl_id, sect->sect_info.addr, &sec_iblock, NULL, &did_protect, H5AC_READ) < 0)
+    if(H5HF_man_dblock_locate(hdr, dxpl_id, sect->sect_info.addr, &sec_iblock, NULL, &did_protect, H5AC__READ_ONLY_FLAG) < 0)
         HGOTO_ERROR(H5E_HEAP, H5E_CANTCOMPUTE, FAIL, "can't compute row & column of section")
 
     /* Increment reference count on indirect block that free section is in */
diff --git a/src/H5HG.c b/src/H5HG.c
index ac8ed8d..46b535d 100644
--- a/src/H5HG.c
+++ b/src/H5HG.c
@@ -246,7 +246,7 @@ done:
  *-------------------------------------------------------------------------
  */
 H5HG_heap_t *
-H5HG_protect(H5F_t *f, hid_t dxpl_id, haddr_t addr, H5AC_protect_t rw)
+H5HG_protect(H5F_t *f, hid_t dxpl_id, haddr_t addr, unsigned flags)
 {
     H5HG_heap_t *heap;          /* Global heap */
     H5HG_heap_t *ret_value;     /* Return value */
@@ -257,8 +257,11 @@ H5HG_protect(H5F_t *f, hid_t dxpl_id, haddr_t addr, H5AC_protect_t rw)
     HDassert(f);
     HDassert(H5F_addr_defined(addr));
 
+    /* only H5AC__READ_ONLY_FLAG may appear in flags */
+    HDassert((flags & (unsigned)(~H5AC__READ_ONLY_FLAG)) == 0);
+
     /* Lock the heap into memory */
-    if(NULL == (heap = (H5HG_heap_t *)H5AC_protect(f, dxpl_id, H5AC_GHEAP, addr, f, rw)))
+    if(NULL == (heap = (H5HG_heap_t *)H5AC_protect(f, dxpl_id, H5AC_GHEAP, addr, f, flags)))
         HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, NULL, "unable to protect global heap")
 
     /* Set the heap's address */
@@ -440,7 +443,7 @@ H5HG_extend(H5F_t *f, hid_t dxpl_id, haddr_t addr, size_t need)
     HDassert(H5F_addr_defined(addr));
 
     /* Protect the heap */
-    if(NULL == (heap = H5HG_protect(f, dxpl_id, addr, H5AC_WRITE)))
+    if(NULL == (heap = H5HG_protect(f, dxpl_id, addr, H5AC__NO_FLAGS_SET)))
         HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "unable to protect global heap")
 
     /* Re-allocate the heap information in memory */
@@ -554,7 +557,7 @@ H5HG_insert(H5F_t *f, hid_t dxpl_id, size_t size, void *obj, H5HG_t *hobj/*out*/
     } /* end if */
     HDassert(H5F_addr_defined(addr));
 
-    if(NULL == (heap = H5HG_protect(f, dxpl_id, addr, H5AC_WRITE)))
+    if(NULL == (heap = H5HG_protect(f, dxpl_id, addr, H5AC__NO_FLAGS_SET)))
         HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "unable to protect global heap")
 
     /* Split the free space to make room for the new object */
@@ -618,7 +621,7 @@ H5HG_read(H5F_t *f, hid_t dxpl_id, H5HG_t *hobj, void *object/*out*/,
     HDassert(hobj);
 
     /* Load the heap */
-    if(NULL == (heap = H5HG_protect(f, dxpl_id, hobj->addr, H5AC_READ)))
+    if(NULL == (heap = H5HG_protect(f, dxpl_id, hobj->addr, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, NULL, "unable to protect global heap")
 
     HDassert(hobj->idx < heap->nused);
@@ -692,7 +695,7 @@ H5HG_link(H5F_t *f, hid_t dxpl_id, const H5HG_t *hobj, int adjust)
 	HGOTO_ERROR(H5E_HEAP, H5E_WRITEERROR, FAIL, "no write intent on file")
 
     /* Load the heap */
-    if(NULL == (heap = H5HG_protect(f, dxpl_id, hobj->addr, H5AC_WRITE)))
+    if(NULL == (heap = H5HG_protect(f, dxpl_id, hobj->addr, H5AC__NO_FLAGS_SET)))
         HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "unable to protect global heap")
 
     if(adjust != 0) {
@@ -755,7 +758,7 @@ H5HG_remove (H5F_t *f, hid_t dxpl_id, H5HG_t *hobj)
         HGOTO_ERROR(H5E_HEAP, H5E_WRITEERROR, FAIL, "no write intent on file")
 
     /* Load the heap */
-    if(NULL == (heap = H5HG_protect(f, dxpl_id, hobj->addr, H5AC_WRITE)))
+    if(NULL == (heap = H5HG_protect(f, dxpl_id, hobj->addr, H5AC__NO_FLAGS_SET)))
         HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "unable to protect global heap")
 
     HDassert(hobj->idx < heap->nused);
diff --git a/src/H5HGcache.c b/src/H5HGcache.c
index aac73ed..5c6bee1 100644
--- a/src/H5HGcache.c
+++ b/src/H5HGcache.c
@@ -62,12 +62,14 @@
 /********************/
 
 /* Metadata cache callbacks */
-static H5HG_heap_t *H5HG_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata);
-static herr_t H5HG_flush(H5F_t *f, hid_t dxpl_id, hbool_t dest, haddr_t addr,
-			 H5HG_heap_t *heap, unsigned H5_ATTR_UNUSED * flags_ptr);
-static herr_t H5HG_dest(H5F_t *f, H5HG_heap_t *heap);
-static herr_t H5HG_clear(H5F_t *f, H5HG_heap_t *heap, hbool_t destroy);
-static herr_t H5HG_size(const H5F_t *f, const H5HG_heap_t *heap, size_t *size_ptr);
+static herr_t H5HG__cache_heap_get_load_size(const void *udata, size_t *image_len);
+static void *H5HG__cache_heap_deserialize(const void *image, size_t len,
+    void *udata, hbool_t *dirty); 
+static herr_t H5HG__cache_heap_image_len(const void *thing, size_t *image_len,
+    hbool_t *compressed_ptr, size_t *compressed_image_len_ptr);
+static herr_t H5HG__cache_heap_serialize(const H5F_t *f, void *image,
+    size_t len, void *thing); 
+static herr_t H5HG__cache_heap_free_icr(void *thing);
 
 
 /*********************/
@@ -76,13 +78,19 @@ static herr_t H5HG_size(const H5F_t *f, const H5HG_heap_t *heap, size_t *size_pt
 
 /* H5HG inherits cache-like properties from H5AC */
 const H5AC_class_t H5AC_GHEAP[1] = {{
-    H5AC_GHEAP_ID,
-    (H5AC_load_func_t)H5HG_load,
-    (H5AC_flush_func_t)H5HG_flush,
-    (H5AC_dest_func_t)H5HG_dest,
-    (H5AC_clear_func_t)H5HG_clear,
-    (H5AC_notify_func_t)NULL,
-    (H5AC_size_func_t)H5HG_size,
+    H5AC_GHEAP_ID,                      /* Metadata client ID */
+    "global heap",                      /* Metadata client name (for debugging) */
+    H5FD_MEM_GHEAP,                     /* File space memory type for client */
+    H5AC__CLASS_SPECULATIVE_LOAD_FLAG,  /* Client class behavior flags */
+    H5HG__cache_heap_get_load_size,     /* 'get_load_size' callback */
+    H5HG__cache_heap_deserialize,       /* 'deserialize' callback */
+    H5HG__cache_heap_image_len,         /* 'image_len' callback */
+    NULL,                               /* 'pre_serialize' callback */
+    H5HG__cache_heap_serialize,         /* 'serialize' callback */
+    NULL,                               /* 'notify' callback */
+    H5HG__cache_heap_free_icr,          /* 'free_icr' callback */
+    NULL,                               /* 'clear' callback */
+    NULL,                               /* 'fsf_size' callback */
 }};
 
 
@@ -98,162 +106,204 @@ const H5AC_class_t H5AC_GHEAP[1] = {{
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HG_load
+ * Function:    H5HG__cache_heap_get_load_size()
  *
- * Purpose:	Loads a global heap collection from disk.
+ * Purpose:	Return the initial speculative read size to the metadata 
+ *		cache.  This size will be used in the initial attempt to read 
+ *		the global heap.  If this read is too small, the cache will 
+ *		try again with the correct value obtained from 
+ *		H5HG__cache_heap_image_len().
  *
- * Return:	Success:	Ptr to a global heap collection.
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
  *
- *		Failure:	NULL
+ * Programmer:  John Mainzer
+ *              7/27/14
  *
- * Programmer:	Robb Matzke
- *              Friday, March 27, 1998
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5HG__cache_heap_get_load_size(const void H5_ATTR_UNUSED *_udata, size_t *image_len)
+{
+    FUNC_ENTER_STATIC_NOERR
+
+    HDassert(image_len);
+
+    *image_len = (size_t)H5HG_MINSIZE;
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5HG__cache_heap_get_load_size() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5HG__cache_heap_deserialize
+ *
+ * Purpose:	Given a buffer containing the on disk image of the global 
+ *		heap, deserialize it, load its contents into a newly allocated
+ *		instance of H5HG_heap_t, and return a pointer to the new instance.
+ *
+ *		Note that this heap client uses speculative reads.  If the supplied
+ *		buffer is too small, we simply make note of the correct size, and 
+ *		wait for the metadata cache to try again.
+ *
+ * Return:      Success:        Pointer to in core representation
+ *              Failure:        NULL
+ *
+ * Programmer:  John Mainzer
+ *              7/27/14
  *
  *-------------------------------------------------------------------------
  */
-static H5HG_heap_t *
-H5HG_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata)
+static void *
+H5HG__cache_heap_deserialize(const void *_image, size_t len, void *_udata,
+    hbool_t H5_ATTR_UNUSED *dirty)
 {
-    H5HG_heap_t	*heap = NULL;
-    uint8_t	*p;
-    size_t	nalloc, need;
-    size_t      max_idx = 0;            /* The maximum index seen */
-    H5HG_heap_t	*ret_value = NULL;      /* Return value */
+    H5F_t       *f = (H5F_t *)_udata;   /* File pointer -- obtained from user data */
+    H5HG_heap_t *heap = NULL;   /* New global heap */
+    uint8_t     *image;         /* Pointer to image to decode */
+    void        *ret_value;     /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
-    /* check arguments */
+    /* Sanity checks */
+    HDassert(_image);
+    HDassert(len >= (size_t)H5HG_MINSIZE);
     HDassert(f);
-    HDassert(H5F_addr_defined(addr));
-    HDassert(udata);
+    HDassert(dirty);
 
-    /* Read the initial 4k page */
+    /* Allocate a new global heap */
     if(NULL == (heap = H5FL_CALLOC(H5HG_heap_t)))
         HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed")
     heap->shared = H5F_SHARED(f);
-    if(NULL == (heap->chunk = H5FL_BLK_MALLOC(gheap_chunk, (size_t)H5HG_MINSIZE)))
+    if(NULL == (heap->chunk = H5FL_BLK_MALLOC(gheap_chunk, len)))
         HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed")
-    if(H5F_block_read(f, H5FD_MEM_GHEAP, addr, (size_t)H5HG_MINSIZE, dxpl_id, heap->chunk) < 0)
-	HGOTO_ERROR(H5E_HEAP, H5E_READERROR, NULL, "unable to read global heap collection")
-    p = heap->chunk;
+
+    /* copy the image buffer into the newly allocate chunk */
+    HDmemcpy(heap->chunk, _image, len);
+
+    image = heap->chunk;
 
     /* Magic number */
-    if(HDmemcmp(p, H5HG_MAGIC, (size_t)H5_SIZEOF_MAGIC))
-	HGOTO_ERROR(H5E_HEAP, H5E_CANTLOAD, NULL, "bad global heap collection signature")
-    p += H5_SIZEOF_MAGIC;
+    if(HDmemcmp(image, H5HG_MAGIC, (size_t)H5_SIZEOF_MAGIC))
+        HGOTO_ERROR(H5E_HEAP, H5E_CANTLOAD, NULL, "bad global heap collection signature")
+    image += H5_SIZEOF_MAGIC;
 
     /* Version */
-    if(H5HG_VERSION != *p++)
-	HGOTO_ERROR(H5E_HEAP, H5E_CANTLOAD, NULL, "wrong version number in global heap")
+    if(H5HG_VERSION != *image++) 
+        HGOTO_ERROR(H5E_HEAP, H5E_CANTLOAD, NULL, "wrong version number in global heap")
 
     /* Reserved */
-    p += 3;
+    image += 3;
 
     /* Size */
-    H5F_DECODE_LENGTH(f, p, heap->size);
+    H5F_DECODE_LENGTH(f, image, heap->size);
     HDassert(heap->size >= H5HG_MINSIZE);
-
-    /*
-     * If we didn't read enough in the first try, then read the rest of the
-     * collection now.
-     */
-    if(heap->size > H5HG_MINSIZE) {
-	haddr_t next_addr = addr + (hsize_t)H5HG_MINSIZE;
-
-	if(NULL == (heap->chunk = H5FL_BLK_REALLOC(gheap_chunk, heap->chunk, heap->size)))
-	    HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed")
-	if(H5F_block_read(f, H5FD_MEM_GHEAP, next_addr, (heap->size - H5HG_MINSIZE), dxpl_id, heap->chunk + H5HG_MINSIZE) < 0)
-	    HGOTO_ERROR(H5E_HEAP, H5E_READERROR, NULL, "unable to read global heap collection")
-    } /* end if */
-
-    /* Decode each object */
-    p = heap->chunk + H5HG_SIZEOF_HDR(f);
-    nalloc = H5HG_NOBJS(f, heap->size);
-
-    /* Calloc the obj array because the file format spec makes no guarantee
-     * about the order of the objects, and unused slots must be set to zero.
-     */
-    if(NULL == (heap->obj = H5FL_SEQ_CALLOC(H5HG_obj_t, nalloc)))
-	HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed")
-
-    heap->nalloc = nalloc;
-    while(p < (heap->chunk + heap->size)) {
-	if((p + H5HG_SIZEOF_OBJHDR(f)) > (heap->chunk + heap->size)) {
-	    /*
-	     * The last bit of space is too tiny for an object header, so we
-	     * assume that it's free space.
-	     */
-	    HDassert(NULL == heap->obj[0].begin);
-	    heap->obj[0].size = (size_t)(((const uint8_t *)heap->chunk + heap->size) - p);
-	    heap->obj[0].begin = p;
-	    p += heap->obj[0].size;
-	} /* end if */
-        else {
-	    unsigned idx;
-	    uint8_t *begin = p;
-
-	    UINT16DECODE(p, idx);
-
-            /* Check if we need more room to store heap objects */
-            if(idx >= heap->nalloc) {
-                size_t new_alloc;       /* New allocation number */
-                H5HG_obj_t *new_obj;	/* New array of object descriptions */
-
-                /* Determine the new number of objects to index */
-                new_alloc = MAX(heap->nalloc * 2, (idx + 1));
-                HDassert(idx < new_alloc);
-
-                /* Reallocate array of objects */
-                if(NULL == (new_obj = H5FL_SEQ_REALLOC(H5HG_obj_t, heap->obj, new_alloc)))
-                    HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed")
-
-                /* Clear newly allocated space */
-                HDmemset(&new_obj[heap->nalloc], 0, (new_alloc - heap->nalloc) * sizeof(heap->obj[0]));
-
-                /* Update heap information */
-                heap->nalloc = new_alloc;
-                heap->obj = new_obj;
-                HDassert(heap->nalloc > heap->nused);
+    HDassert((len == H5HG_MINSIZE) /* first try */ || 
+             ((len == heap->size) && (len > H5HG_MINSIZE))); /* second try */
+    
+    if(len == heap->size) {     /* proceed with the deserialize */
+        size_t       max_idx = 0;
+        size_t       nalloc;
+
+        /* Decode each object */
+        image = heap->chunk + H5HG_SIZEOF_HDR(f);
+        nalloc = H5HG_NOBJS(f, heap->size);
+
+        /* Calloc the obj array because the file format spec makes no guarantee
+         * about the order of the objects, and unused slots must be set to zero.
+         */
+        if(NULL == (heap->obj = H5FL_SEQ_CALLOC(H5HG_obj_t, nalloc)))
+            HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed")
+        heap->nalloc = nalloc;
+
+        while(image < (heap->chunk + heap->size)) {
+            if((image + H5HG_SIZEOF_OBJHDR(f)) > (heap->chunk + heap->size)) {
+                /*
+                 * The last bit of space is too tiny for an object header, so
+                 * we assume that it's free space.
+                 */
+                HDassert(NULL == heap->obj[0].begin);
+                heap->obj[0].size = (size_t)(((const uint8_t *)heap->chunk + heap->size) - image);
+                heap->obj[0].begin = image;
+                image += heap->obj[0].size;
             } /* end if */
-
-	    UINT16DECODE(p, heap->obj[idx].nrefs);
-	    p += 4; /*reserved*/
-	    H5F_DECODE_LENGTH(f, p, heap->obj[idx].size);
-	    heap->obj[idx].begin = begin;
-
-	    /*
-	     * The total storage size includes the size of the object header
-	     * and is zero padded so the next object header is properly
-	     * aligned. The entire obj array was calloc'ed, so no need to zero
-	     * the space here. The last bit of space is the free space object
-	     * whose size is never padded and already includes the object
-	     * header.
-	     */
-	    if(idx > 0) {
-		need = H5HG_SIZEOF_OBJHDR(f) + H5HG_ALIGN(heap->obj[idx].size);
-
-                if(idx > max_idx)
-                    max_idx = idx;
-	    } /* end if */
-            else
-		need = heap->obj[idx].size;
-	    p = begin + need;
-	} /* end else */
-    } /* end while */
-    HDassert(p == heap->chunk + heap->size);
-    HDassert(H5HG_ISALIGNED(heap->obj[0].size));
-
-    /* Set the next index value to use */
-    if(max_idx > 0)
-        heap->nused = max_idx + 1;
+            else {
+                size_t need;
+                unsigned idx;
+                uint8_t *begin = image;
+
+                UINT16DECODE(image, idx);
+
+                /* Check if we need more room to store heap objects */
+                if(idx >= heap->nalloc) {
+                    size_t new_alloc;       /* New allocation number */
+                    H5HG_obj_t *new_obj;    /* New array of object   descriptions          */
+
+                    /* Determine the new number of objects to index */
+                    new_alloc = MAX(heap->nalloc * 2, (idx + 1));
+                    HDassert(idx < new_alloc);
+
+                    /* Reallocate array of objects */
+                    if(NULL == (new_obj = H5FL_SEQ_REALLOC(H5HG_obj_t, heap->obj, new_alloc)))
+                        HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed")
+
+                    /* Clear newly allocated space */
+                    HDmemset(&new_obj[heap->nalloc], 0, (new_alloc - heap->nalloc) * sizeof(heap->obj[0]));
+
+                    /* Update heap information */
+                    heap->nalloc = new_alloc;
+                    heap->obj = new_obj;
+                    HDassert(heap->nalloc > heap->nused);
+                } /* end if */
+
+                UINT16DECODE(image, heap->obj[idx].nrefs);
+                image += 4; /*reserved*/
+                H5F_DECODE_LENGTH(f, image, heap->obj[idx].size);
+                heap->obj[idx].begin = begin;
+
+                /*
+                 * The total storage size includes the size of the object 
+                 * header and is zero padded so the next object header is 
+                 * properly aligned. The entire obj array was calloc'ed, 
+                 * so no need to zero the space here. The last bit of space 
+                 * is the free space object whose size is never padded and 
+                 * already includes the object header.
+                 */
+                if(idx > 0) {
+                    need = H5HG_SIZEOF_OBJHDR(f) + H5HG_ALIGN(heap->obj[idx].size);
+                    if(idx > max_idx)
+                        max_idx = idx;
+                } /* end if */
+                else
+                    need = heap->obj[idx].size;
+
+                image = begin + need;
+            } /* end else */
+        } /* end while */
+
+        HDassert(image == heap->chunk + heap->size);
+        HDassert(H5HG_ISALIGNED(heap->obj[0].size));
+
+        /* Set the next index value to use */
+        if(max_idx > 0)
+            heap->nused = max_idx + 1;
+        else
+            heap->nused = 1;
+
+        HDassert(max_idx < heap->nused);
+
+        /* Add the new heap to the CWFS list for the file */
+        if(H5F_cwfs_add(f, heap) < 0)
+            HGOTO_ERROR(H5E_HEAP, H5E_CANTINIT, NULL, "unable to add global heap collection to file's CWFS")
+    } /* end if ( len == heap->size ) */
     else
-        heap->nused = 1;
-
-    HDassert(max_idx < heap->nused);
-
-    /* Add the new heap to the CWFS list for the file */
-    if(H5F_cwfs_add(f, heap) < 0)
-	HGOTO_ERROR(H5E_HEAP, H5E_CANTINIT, NULL, "unable to add global heap collection to file's CWFS")
+        /* if len is less than heap size, then the initial speculative 
+         * read was too small.  In this case we return without reporting
+         * failure.  H5C_load_entry() will call H5HG__cache_heap_image_len()
+         * to get the actual read size, and then repeat the read with the 
+         * correct size, and call this function a second time.
+         */
+        HDassert(len < heap->size);
 
     ret_value = heap;
 
@@ -263,154 +313,126 @@ done:
             HDONE_ERROR(H5E_HEAP, H5E_CANTFREE, NULL, "unable to destroy global heap collection")
 
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5HG_load() */
+} /* end H5HG__cache_heap_deserialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HG_flush
+ * Function:    H5HG__cache_heap_image_len
  *
- * Purpose:	Flushes a global heap collection from memory to disk if it's
- *		dirty.  Optionally deletes teh heap from memory.
+ * Purpose:	Return the on disk image size of the global heap to the 
+ *		metadata cache via the image_len.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
  *
- * Programmer:	Robb Matzke
- *              Friday, March 27, 1998
+ * Programmer:  John Mainzer
+ *              7/27/14
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5HG_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5HG_heap_t *heap, unsigned H5_ATTR_UNUSED * flags_ptr)
+H5HG__cache_heap_image_len(const void *_thing, size_t *image_len, 
+    hbool_t H5_ATTR_UNUSED *compressed_ptr, size_t H5_ATTR_UNUSED *compressed_image_len_ptr)
 {
-    herr_t ret_value = SUCCEED;       /* Return value */
+    const H5HG_heap_t *heap = (const H5HG_heap_t *)_thing;
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC_NOERR
 
-    /* Check arguments */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
-    HDassert(H5F_addr_eq(addr, heap->addr));
+    /* Sanity checks */
     HDassert(heap);
+    HDassert(heap->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(heap->cache_info.type == H5AC_GHEAP);
+    HDassert(heap->size >= H5HG_MINSIZE);
+    HDassert(image_len);
 
-    if(heap->cache_info.is_dirty) {
-	if(H5F_block_write(f, H5FD_MEM_GHEAP, addr, heap->size, dxpl_id, heap->chunk) < 0)
-	    HGOTO_ERROR(H5E_HEAP, H5E_WRITEERROR, FAIL, "unable to write global heap collection to file")
-	heap->cache_info.is_dirty = FALSE;
-    } /* end if */
+    *image_len = heap->size;
 
-    if(destroy)
-        if(H5HG_dest(f, heap) < 0)
-	    HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to destroy global heap collection")
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5HG__cache_heap_image_len() */
 
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5HG_flush() */
+/**************************************/
+/* no H5HG_cache_heap_pre_serialize() */
+/**************************************/
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HG_dest
+ * Function:    H5HG__cache_heap_serialize
+ *
+ * Purpose:	Given an appropriately sized buffer and an instance of 
+ *		H5HG_heap_t, serialize the global heap for writing to file,
+ *		and copy the serialized verion into the buffer.
  *
- * Purpose:	Destroys a global heap collection in memory
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
  *
- * Programmer:	Quincey Koziol
- *              Wednesday, January 15, 2003
+ * Programmer:  John Mainzer
+ *              7/27/14
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5HG_dest(H5F_t *f, H5HG_heap_t *heap)
+H5HG__cache_heap_serialize(const H5F_t *f, void *image, size_t len,
+    void *_thing)
 {
-    herr_t ret_value = SUCCEED;         /* Return value */
+    H5HG_heap_t *heap = (H5HG_heap_t *)_thing;
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC_NOERR
 
-    /* Check arguments */
+    HDassert(f);
+    HDassert(image);
     HDassert(heap);
+    HDassert(heap->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(heap->cache_info.type == H5AC_GHEAP);
+    HDassert(heap->size == len);
+    HDassert(heap->chunk);
 
-    /* Verify that node is clean */
-    HDassert(heap->cache_info.is_dirty == FALSE);
+    /* copy the image into the buffer */
+    HDmemcpy(image, heap->chunk, len);
 
-    /* If we're going to free the space on disk, the address must be valid */
-    HDassert(!heap->cache_info.free_file_space_on_destroy || H5F_addr_defined(heap->cache_info.addr));
-
-    /* Check for freeing file space for globalheap */
-    if(heap->cache_info.free_file_space_on_destroy) {
-        /* Release the space on disk */
-        /* (XXX: Nasty usage of internal DXPL value! -QAK) */
-        if(H5MF_xfree(f, H5FD_MEM_GHEAP, H5AC_dxpl_id, heap->cache_info.addr, (hsize_t)heap->size) < 0)
-            HGOTO_ERROR(H5E_BTREE, H5E_CANTFREE, FAIL, "unable to free global heap")
-    } /* end if */
-
-    /* Destroy global heap collection */
-    if(H5HG_free(heap) < 0)
-        HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to destroy global heap collection")
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5HG__cache_heap_serialize() */
 
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* H5HG_dest() */
+/****************************************/
+/* no H5HG_cache_heap_notify() function */
+/****************************************/
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HG_clear
+ * Function:    H5HG__cache_heap_free_icr
  *
- * Purpose:	Mark a global heap in memory as non-dirty.
+ * Purpose:	Free the in memory representation of the supplied global heap.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Note:	The metadata cache sets the object's cache_info.magic to
+ *		H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC before calling a free_icr
+ *		callback (checked in assert).
  *
- * Programmer:	Quincey Koziol
- *              Thursday, March 20, 2003
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
+ *
+ * Programmer:  John Mainzer
+ *              7/27/14
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5HG_clear(H5F_t *f, H5HG_heap_t *heap, hbool_t destroy)
+H5HG__cache_heap_free_icr(void *_thing)
 {
+    H5HG_heap_t *heap = (H5HG_heap_t *)_thing;
     herr_t      ret_value = SUCCEED;    /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
     /* Sanity checks */
     HDassert(heap);
+    HDassert(heap->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC);
+    HDassert(heap->cache_info.type == H5AC_GHEAP);
 
-    /* Mark heap as clean */
-    heap->cache_info.is_dirty = FALSE;
-
-    if(destroy)
-        if(H5HG_dest(f, heap) < 0)
-	    HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to destroy global heap collection")
+    /* Destroy global heap collection */
+    if(H5HG_free(heap) < 0)
+        HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to destroy global heap collection")
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* H5HG_clear() */
-
-
-/*-------------------------------------------------------------------------
- * Function:	H5HG_size
- *
- * Purpose:	Compute the size in bytes of the specified instance of
- *              H5HG_heap_t on disk, and return it in *len_ptr.  On failure,
- *              the value of *len_ptr is undefined.
- *
- * Return:	Non-negative on success/Negative on failure
- *
- * Programmer:	John Mainzer
- *              5/13/04
- *
- *-------------------------------------------------------------------------
- */
-static herr_t
-H5HG_size(const H5F_t H5_ATTR_UNUSED *f, const H5HG_heap_t *heap, size_t *size_ptr)
-{
-    FUNC_ENTER_NOAPI_NOINIT_NOERR
-
-    /* Check arguments */
-    HDassert(heap);
-    HDassert(size_ptr);
-
-    *size_ptr = heap->size;
-
-    FUNC_LEAVE_NOAPI(SUCCEED)
-} /* H5HG_size() */
+} /* end H5HG__cache_heap_free_icr() */
 
diff --git a/src/H5HGdbg.c b/src/H5HGdbg.c
index 16d8c49..c79aac8 100644
--- a/src/H5HGdbg.c
+++ b/src/H5HGdbg.c
@@ -103,7 +103,7 @@ H5HG_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE *stream, int indent,
     HDassert(indent >= 0);
     HDassert(fwidth >= 0);
 
-    if(NULL == (h = H5HG_protect(f, dxpl_id, addr, H5AC_READ)))
+    if(NULL == (h = H5HG_protect(f, dxpl_id, addr, H5AC__READ_ONLY_FLAG)))
         HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "unable to protect global heap collection");
 
     HDfprintf(stream, "%*sGlobal Heap Collection...\n", indent, "");
diff --git a/src/H5HGpkg.h b/src/H5HGpkg.h
index f3546a2..9137e7b 100644
--- a/src/H5HGpkg.h
+++ b/src/H5HGpkg.h
@@ -143,7 +143,7 @@ struct H5HG_heap_t {
 /* Package Private Prototypes */
 /******************************/
 H5_DLL herr_t H5HG_free(H5HG_heap_t *heap);
-H5_DLL H5HG_heap_t *H5HG_protect(H5F_t *f, hid_t dxpl_id, haddr_t addr, H5AC_protect_t rw);
+H5_DLL H5HG_heap_t *H5HG_protect(H5F_t *f, hid_t dxpl_id, haddr_t addr, unsigned flags);
 
 #endif /* _H5HGpkg_H */
 
diff --git a/src/H5HL.c b/src/H5HL.c
index b1b5b24..eae0482 100644
--- a/src/H5HL.c
+++ b/src/H5HL.c
@@ -441,7 +441,7 @@ done:
  *-------------------------------------------------------------------------
  */
 H5HL_t *
-H5HL_protect(H5F_t *f, hid_t dxpl_id, haddr_t addr, H5AC_protect_t rw)
+H5HL_protect(H5F_t *f, hid_t dxpl_id, haddr_t addr, unsigned flags)
 {
     H5HL_cache_prfx_ud_t prfx_udata; /* User data for protecting local heap prefix */
     H5HL_prfx_t *prfx = NULL;   /* Local heap prefix */
@@ -457,14 +457,19 @@ H5HL_protect(H5F_t *f, hid_t dxpl_id, haddr_t addr, H5AC_protect_t rw)
     HDassert(f);
     HDassert(H5F_addr_defined(addr));
 
+    /* only the H5AC__READ_ONLY_FLAG may appear in flags */
+    HDassert((flags & (unsigned)(~H5AC__READ_ONLY_FLAG)) == 0);
+
     /* Construct the user data for protect callback */
+    prfx_udata.made_attempt = FALSE;
     prfx_udata.sizeof_size = H5F_SIZEOF_SIZE(f);
     prfx_udata.sizeof_addr = H5F_SIZEOF_ADDR(f);
     prfx_udata.prfx_addr = addr;
     prfx_udata.sizeof_prfx = H5HL_SIZEOF_HDR(f);
+    prfx_udata.loaded = FALSE;
 
     /* Protect the local heap prefix */
-    if(NULL == (prfx = (H5HL_prfx_t *)H5AC_protect(f, dxpl_id, H5AC_LHEAP_PRFX, addr, &prfx_udata, rw)))
+    if(NULL == (prfx = (H5HL_prfx_t *)H5AC_protect(f, dxpl_id, H5AC_LHEAP_PRFX, addr, &prfx_udata, flags)))
         HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, NULL, "unable to load heap prefix")
 
     /* Get the pointer to the heap */
@@ -486,7 +491,7 @@ H5HL_protect(H5F_t *f, hid_t dxpl_id, haddr_t addr, H5AC_protect_t rw)
             dblk_udata.loaded = FALSE;
 
             /* Protect the local heap data block */
-            if(NULL == (dblk = (H5HL_dblk_t *)H5AC_protect(f, dxpl_id, H5AC_LHEAP_DBLK, heap->dblk_addr, &dblk_udata, rw)))
+            if(NULL == (dblk = (H5HL_dblk_t *)H5AC_protect(f, dxpl_id, H5AC_LHEAP_DBLK, heap->dblk_addr, &dblk_udata, flags)))
                 HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, NULL, "unable to load heap data block")
 
             /* Pin the prefix, if the data block was loaded from file */
@@ -1071,13 +1076,15 @@ H5HL_delete(H5F_t *f, hid_t dxpl_id, haddr_t addr)
     HDassert(H5F_addr_defined(addr));
 
     /* Construct the user data for protect callback */
+    prfx_udata.made_attempt = FALSE;
     prfx_udata.sizeof_size = H5F_SIZEOF_SIZE(f);
     prfx_udata.sizeof_addr = H5F_SIZEOF_ADDR(f);
     prfx_udata.prfx_addr = addr;
     prfx_udata.sizeof_prfx = H5HL_SIZEOF_HDR(f);
+    prfx_udata.loaded = FALSE;
 
     /* Protect the local heap prefix */
-    if(NULL == (prfx = (H5HL_prfx_t *)H5AC_protect(f, dxpl_id, H5AC_LHEAP_PRFX, addr, &prfx_udata, H5AC_WRITE)))
+    if(NULL == (prfx = (H5HL_prfx_t *)H5AC_protect(f, dxpl_id, H5AC_LHEAP_PRFX, addr, &prfx_udata, H5AC__NO_FLAGS_SET)))
         HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "unable to load heap prefix")
 
     /* Get the pointer to the heap */
@@ -1092,7 +1099,7 @@ H5HL_delete(H5F_t *f, hid_t dxpl_id, haddr_t addr)
         dblk_udata.loaded = FALSE;
 
         /* Protect the local heap data block */
-        if(NULL == (dblk = (H5HL_dblk_t *)H5AC_protect(f, dxpl_id, H5AC_LHEAP_DBLK, heap->dblk_addr, &dblk_udata, H5AC_WRITE)))
+        if(NULL == (dblk = (H5HL_dblk_t *)H5AC_protect(f, dxpl_id, H5AC_LHEAP_DBLK, heap->dblk_addr, &dblk_udata, H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "unable to load heap data block")
 
         /* Pin the prefix, if the data block was loaded from file */
@@ -1147,13 +1154,15 @@ H5HL_get_size(H5F_t *f, hid_t dxpl_id, haddr_t addr, size_t *size)
     HDassert(size);
 
     /* Construct the user data for protect callback */
+    prfx_udata.made_attempt = FALSE;
     prfx_udata.sizeof_size = H5F_SIZEOF_SIZE(f);
     prfx_udata.sizeof_addr = H5F_SIZEOF_ADDR(f);
     prfx_udata.prfx_addr = addr;
     prfx_udata.sizeof_prfx = H5HL_SIZEOF_HDR(f);
+    prfx_udata.loaded = FALSE;
 
     /* Protect the local heap prefix */
-    if(NULL == (prfx = (H5HL_prfx_t *)H5AC_protect(f, dxpl_id, H5AC_LHEAP_PRFX, addr, &prfx_udata, H5AC_READ)))
+    if(NULL == (prfx = (H5HL_prfx_t *)H5AC_protect(f, dxpl_id, H5AC_LHEAP_PRFX, addr, &prfx_udata, H5AC__READ_ONLY_FLAG)))
         HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "unable to load heap prefix")
 
     /* Get the pointer to the heap */
@@ -1199,13 +1208,15 @@ H5HL_heapsize(H5F_t *f, hid_t dxpl_id, haddr_t addr, hsize_t *heap_size)
     HDassert(heap_size);
 
     /* Construct the user data for protect callback */
+    prfx_udata.made_attempt = FALSE;
     prfx_udata.sizeof_size = H5F_SIZEOF_SIZE(f);
     prfx_udata.sizeof_addr = H5F_SIZEOF_ADDR(f);
     prfx_udata.prfx_addr = addr;
     prfx_udata.sizeof_prfx = H5HL_SIZEOF_HDR(f);
+    prfx_udata.loaded = FALSE;
 
     /* Protect the local heap prefix */
-    if(NULL == (prfx = (H5HL_prfx_t *)H5AC_protect(f, dxpl_id, H5AC_LHEAP_PRFX, addr, &prfx_udata, H5AC_READ)))
+    if(NULL == (prfx = (H5HL_prfx_t *)H5AC_protect(f, dxpl_id, H5AC_LHEAP_PRFX, addr, &prfx_udata, H5AC__READ_ONLY_FLAG)))
         HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "unable to load heap prefix")
 
     /* Get the pointer to the heap */
diff --git a/src/H5HLcache.c b/src/H5HLcache.c
index b2c764d..2054e34 100644
--- a/src/H5HLcache.c
+++ b/src/H5HLcache.c
@@ -69,18 +69,26 @@
 /********************/
 
 /* Metadata cache callbacks */
-static void *H5HL_prefix_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata);
-static herr_t H5HL_prefix_flush(H5F_t *f, hid_t dxpl_id, hbool_t dest, haddr_t addr,
-    void *thing, unsigned *flags_ptr);
-static herr_t H5HL_prefix_dest(H5F_t *f, void *thing);
-static herr_t H5HL_prefix_clear(H5F_t *f, void *thing, hbool_t destroy);
-static herr_t H5HL_prefix_size(const H5F_t *f, const void *thing, size_t *size_ptr);
-static void *H5HL_datablock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata);
-static herr_t H5HL_datablock_flush(H5F_t *f, hid_t dxpl_id, hbool_t dest, haddr_t addr,
-    void *thing, unsigned *flags_ptr);
-static herr_t H5HL_datablock_dest(H5F_t *f, void *thing);
-static herr_t H5HL_datablock_clear(H5F_t *f, void *thing, hbool_t destroy);
-static herr_t H5HL_datablock_size(const H5F_t *f, const void *thing, size_t *size_ptr);
+static herr_t H5HL__cache_prefix_get_load_size(const void *udata, size_t *image_len);
+static void *H5HL__cache_prefix_deserialize(const void *image, size_t len,
+    void *udata, hbool_t *dirty);
+static herr_t H5HL__cache_prefix_image_len(const void *thing, 
+    size_t *image_len, hbool_t *compressed_ptr, 
+    size_t *compressed_image_len_ptr);
+static herr_t H5HL__cache_prefix_serialize(const H5F_t *f, void *image,
+    size_t len, void *thing); 
+static herr_t H5HL__cache_prefix_free_icr(void *thing);
+
+static herr_t H5HL__cache_datablock_get_load_size(const void *udata,
+    size_t *image_len); 
+static void *H5HL__cache_datablock_deserialize(const void *image, size_t len,
+    void *udata, hbool_t *dirty); 
+static herr_t H5HL__cache_datablock_image_len(const void *thing, 
+    size_t *image_len, hbool_t *compressed_ptr, 
+    size_t *compressed_image_len_ptr);
+static herr_t H5HL__cache_datablock_serialize(const H5F_t *f, void *image,
+    size_t len, void *thing); 
+static herr_t H5HL__cache_datablock_free_icr(void *thing);
 
 
 /*********************/
@@ -89,23 +97,35 @@ static herr_t H5HL_datablock_size(const H5F_t *f, const void *thing, size_t *siz
 
 /* H5HL inherits cache-like properties from H5AC */
 const H5AC_class_t H5AC_LHEAP_PRFX[1] = {{
-    H5AC_LHEAP_PRFX_ID,
-    H5HL_prefix_load,
-    H5HL_prefix_flush,
-    H5HL_prefix_dest,
-    H5HL_prefix_clear,
-    NULL,
-    H5HL_prefix_size,
+    H5AC_LHEAP_PRFX_ID,                 /* Metadata client ID */
+    "local heap prefix",                /* Metadata client name (for debugging) */
+    H5FD_MEM_LHEAP,                     /* File space memory type for client */
+    H5AC__CLASS_SPECULATIVE_LOAD_FLAG,  /* Client class behavior flags */
+    H5HL__cache_prefix_get_load_size,   /* 'get_load_size' callback */
+    H5HL__cache_prefix_deserialize,     /* 'deserialize' callback */
+    H5HL__cache_prefix_image_len,       /* 'image_len' callback */
+    NULL,                               /* 'pre_serialize' callback */
+    H5HL__cache_prefix_serialize,       /* 'serialize' callback */
+    NULL,                               /* 'notify' callback */
+    H5HL__cache_prefix_free_icr,        /* 'free_icr' callback */
+    NULL,                               /* 'clear' callback */
+    NULL,                               /* 'fsf_size' callback */
 }};
 
 const H5AC_class_t H5AC_LHEAP_DBLK[1] = {{
-    H5AC_LHEAP_DBLK_ID,
-    H5HL_datablock_load,
-    H5HL_datablock_flush,
-    H5HL_datablock_dest,
-    H5HL_datablock_clear,
-    NULL,
-    H5HL_datablock_size,
+    H5AC_LHEAP_DBLK_ID,                 /* Metadata client ID */
+    "local heap datablock",             /* Metadata client name (for debugging) */
+    H5FD_MEM_LHEAP,                     /* File space memory type for client */
+    H5AC__CLASS_NO_FLAGS_SET,           /* Client class behavior flags */
+    H5HL__cache_datablock_get_load_size,/* 'get_load_size' callback */
+    H5HL__cache_datablock_deserialize,  /* 'deserialize' callback */
+    H5HL__cache_datablock_image_len,    /* 'image_len' callback */
+    NULL,                               /* 'pre_serialize' callback */
+    H5HL__cache_datablock_serialize,    /* 'serialize' callback */
+    NULL,                               /* 'notify' callback */
+    H5HL__cache_datablock_free_icr,     /* 'free_icr' callback */
+    NULL,                               /* 'clear' callback */
+    NULL,                               /* 'fsf_size' callback */
 }};
 
 
@@ -149,7 +169,7 @@ H5HL__fl_deserialize(H5HL_t *heap)
     /* Build free list */
     free_block = heap->free_block;
     while(H5HL_FREE_NULL != free_block) {
-        const uint8_t *p;               /* Pointer into image buffer */
+        const uint8_t *image;           /* Pointer into image buffer */
 
         /* Sanity check */
         if(free_block >= heap->dblk_size)
@@ -163,13 +183,13 @@ H5HL__fl_deserialize(H5HL_t *heap)
         fl->next = NULL;
 
         /* Decode offset of next free block */
-        p = heap->dblk_image + free_block;
-        H5F_DECODE_LENGTH_LEN(p, free_block, heap->sizeof_size);
+        image = heap->dblk_image + free_block;
+        H5F_DECODE_LENGTH_LEN(image, free_block, heap->sizeof_size);
         if(free_block == 0)
             HGOTO_ERROR(H5E_HEAP, H5E_BADVALUE, FAIL, "free block size is zero?")
 
         /* Decode length of this free block */
-        H5F_DECODE_LENGTH_LEN(p, fl->size, heap->sizeof_size);
+        H5F_DECODE_LENGTH_LEN(image, fl->size, heap->sizeof_size);
         if((fl->offset + fl->size) > heap->dblk_size)
             HGOTO_ERROR(H5E_HEAP, H5E_BADRANGE, FAIL, "bad heap free list")
 
@@ -217,17 +237,17 @@ H5HL__fl_serialize(const H5HL_t *heap)
 
     /* Serialize the free list into the heap data's image */
     for(fl = heap->freelist; fl; fl = fl->next) {
-        uint8_t     *p;                     /* Pointer into raw data buffer */
+        uint8_t     *image;     /* Pointer into raw data buffer */
 
         HDassert(fl->offset == H5HL_ALIGN(fl->offset));
-        p = heap->dblk_image + fl->offset;
+        image = heap->dblk_image + fl->offset;
 
         if(fl->next)
-            H5F_ENCODE_LENGTH_LEN(p, fl->next->offset, heap->sizeof_size)
+            H5F_ENCODE_LENGTH_LEN(image, fl->next->offset, heap->sizeof_size)
         else
-            H5F_ENCODE_LENGTH_LEN(p, H5HL_FREE_NULL, heap->sizeof_size)
+            H5F_ENCODE_LENGTH_LEN(image, H5HL_FREE_NULL, heap->sizeof_size)
 
-        H5F_ENCODE_LENGTH_LEN(p, fl->size, heap->sizeof_size)
+        H5F_ENCODE_LENGTH_LEN(image, fl->size, heap->sizeof_size)
     } /* end for */
 
     FUNC_LEAVE_NOAPI_VOID
@@ -235,69 +255,88 @@ H5HL__fl_serialize(const H5HL_t *heap)
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HL_prefix_load
+ * Function:    H5HL__cache_prefix_get_load_size()
  *
- * Purpose:	Loads a local heap prefix from disk.
+ * Purpose:	Return the size of the buffer the metadata cache should 
+ *		load from file and pass to the deserialize routine.
  *
- * Return:	Success:	Ptr to a local heap memory data structure.
- *		Failure:	NULL
+ *		The version 2 metadata cache callbacks included a test to 
+ *		ensure that the read did not pass the end of file, but this 
+ *		functionality has been moved to H5C_load_entry().  Thus 
+ *		all this function does is set *image_len equal to 
+ *		H5HL_SPEC_READ_SIZE, leaving it to the metadata cache to 
+ *		reduce the size of the read if appropriate.
  *
- * Programmer:	Robb Matzke
- *		matzke@llnl.gov
- *		Jul 17 1997
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
+ *
+ * Programmer:  John Mainzer
+ *              6/21/14
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5HL__cache_prefix_get_load_size(const void H5_ATTR_UNUSED *_udata, size_t *image_len)
+{
+    FUNC_ENTER_STATIC_NOERR
+
+    HDassert(image_len);
+
+    *image_len = H5HL_SPEC_READ_SIZE;
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5HL__cache_prefix_get_load_size() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5HL__cache_prefix_deserialize
+ *
+ * Purpose:	Given a buffer containing the on disk image of the local 
+ *		heap prefix, deserialize it, load its contents into a newly allocated
+ *		instance of H5HL_prfx_t, and return a pointer to the new instance.
+ *
+ * Return:      Success:        Pointer to in core representation
+ *              Failure:        NULL
+ *
+ * Programmer:  John Mainzer
+ *              6/21/14
  *
  *-------------------------------------------------------------------------
  */
 static void *
-H5HL_prefix_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
+H5HL__cache_prefix_deserialize(const void *_image, size_t len, void *_udata,
+    hbool_t H5_ATTR_UNUSED *dirty)
 {
-    H5HL_t *heap = NULL;            /* Local heap */
-    H5HL_prfx_t *prfx = NULL;       /* Heap prefix deserialized */
+    H5HL_t               *heap = NULL;  /* Local heap */
+    H5HL_prfx_t          *prfx = NULL;  /* Heap prefix deserialized */
+    const uint8_t        *image = (const uint8_t *)_image;      /* Pointer into decoding buffer */
     H5HL_cache_prfx_ud_t *udata = (H5HL_cache_prfx_ud_t *)_udata;       /* User data for callback */
-    uint8_t		buf[H5HL_SPEC_READ_SIZE];   /* Buffer for decoding */
-    size_t	        spec_read_size; /* Size of buffer to speculatively read in */
-    const uint8_t	*p;         /* Pointer into decoding buffer */
-    haddr_t             eoa;        /* Relative end of file address */
-    hsize_t min;                    /* temp min value to avoid macro nesting */
-    H5HL_prfx_t *ret_value;         /* Return value */
+    void                 *ret_value;    /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
-    /* check arguments */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
+    /* Check arguments */
+    HDassert(image);
+    HDassert(len > 0);
     HDassert(udata);
     HDassert(udata->sizeof_size > 0);
     HDassert(udata->sizeof_addr > 0);
     HDassert(udata->sizeof_prfx > 0);
-    HDassert(udata->sizeof_prfx <= sizeof(buf));
-
-    /* Make certain we don't speculatively read off the end of the file */
-    if(HADDR_UNDEF == (eoa = H5F_get_eoa(f, H5FD_MEM_LHEAP)))
-        HGOTO_ERROR(H5E_HEAP, H5E_CANTGET, NULL, "unable to determine file size")
-
-    /* Compute the size of the speculative local heap prefix buffer */
-    min = MIN(eoa - addr, H5HL_SPEC_READ_SIZE);
-    H5_CHECKED_ASSIGN(spec_read_size, size_t, min, hsize_t);
-    HDassert(spec_read_size >= udata->sizeof_prfx);
-
-    /* Attempt to speculatively read both local heap prefix and heap data */
-    if(H5F_block_read(f, H5FD_MEM_LHEAP, addr, spec_read_size, dxpl_id, buf) < 0)
-	HGOTO_ERROR(H5E_HEAP, H5E_READERROR, NULL, "unable to read local heap prefix")
-    p = buf;
+    HDassert(H5F_addr_defined(udata->prfx_addr));
+    HDassert(dirty);
 
     /* Check magic number */
-    if(HDmemcmp(p, H5HL_MAGIC, (size_t)H5_SIZEOF_MAGIC))
-	HGOTO_ERROR(H5E_HEAP, H5E_BADVALUE, NULL, "bad local heap signature")
-    p += H5_SIZEOF_MAGIC;
+    if(HDmemcmp(image, H5HL_MAGIC, (size_t)H5_SIZEOF_MAGIC)) 
+        HGOTO_ERROR(H5E_HEAP, H5E_BADVALUE, NULL, "bad local heap signature")
+    image += H5_SIZEOF_MAGIC;
 
     /* Version */
-    if(H5HL_VERSION != *p++)
-	HGOTO_ERROR(H5E_HEAP, H5E_BADVALUE, NULL, "wrong version number in local heap")
+    if(H5HL_VERSION != *image++) 
+        HGOTO_ERROR(H5E_HEAP, H5E_BADVALUE, NULL, "wrong version number in local heap")
 
     /* Reserved */
-    p += 3;
-
+    image += 3;
+    
     /* Allocate space in memory for the heap */
     if(NULL == (heap = H5HL_new(udata->sizeof_size, udata->sizeof_addr, udata->sizeof_prfx)))
         HGOTO_ERROR(H5E_HEAP, H5E_CANTALLOC, NULL, "can't allocate local heap structure")
@@ -311,16 +350,16 @@ H5HL_prefix_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
     heap->prfx_size = udata->sizeof_prfx;
 
     /* Heap data size */
-    H5F_DECODE_LENGTH_LEN(p, heap->dblk_size, udata->sizeof_size);
+    H5F_DECODE_LENGTH_LEN(image, heap->dblk_size, udata->sizeof_size);
 
     /* Free list head */
-    H5F_DECODE_LENGTH_LEN(p, heap->free_block, udata->sizeof_size);
+    H5F_DECODE_LENGTH_LEN(image, heap->free_block, udata->sizeof_size);
 
     if((heap->free_block != H5HL_FREE_NULL) && (heap->free_block >= heap->dblk_size))
         HGOTO_ERROR(H5E_HEAP, H5E_BADVALUE, NULL, "bad heap free list")
 
     /* Heap data address */
-    H5F_addr_decode_len(udata->sizeof_addr, &p, &(heap->dblk_addr));
+    H5F_addr_decode_len(udata->sizeof_addr, &image, &(heap->dblk_addr));
 
     /* Check if heap block exists */
     if(heap->dblk_size) {
@@ -329,35 +368,53 @@ H5HL_prefix_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
             /* Note that the heap should be a single object in the cache */
             heap->single_cache_obj = TRUE;
 
-            /* Allocate space for the heap data image */
-            if(NULL == (heap->dblk_image = H5FL_BLK_MALLOC(lheap_chunk, heap->dblk_size)))
-                HGOTO_ERROR(H5E_HEAP, H5E_CANTALLOC, NULL, "memory allocation failed")
+            /* Check if the current buffer from the speculative read 
+             * already has the heap data 
+             */
+            if(len >= (heap->prfx_size + heap->dblk_size)) {
+                /* Allocate space for the heap data image */
+                if(NULL == (heap->dblk_image = H5FL_BLK_MALLOC(lheap_chunk, heap->dblk_size)))
+                    HGOTO_ERROR(H5E_HEAP, H5E_CANTALLOC, NULL, "memory allocation failed")
 
-            /* Check if the current buffer from the speculative read already has the heap data */
-            if(spec_read_size >= (heap->prfx_size + heap->dblk_size)) {
-                /* Set p to the start of the data block.  This is necessary
+                /* Set image to the start of the data block.  This is necessary
                  * because there may be a gap between the used portion of the
                  * prefix and the data block due to alignment constraints. */
-                p = buf + heap->prfx_size;
+                image = ((const uint8_t *)_image) + heap->prfx_size;
 
                 /* Copy the heap data from the speculative read buffer */
-                HDmemcpy(heap->dblk_image, p, heap->dblk_size);
+                HDmemcpy(heap->dblk_image, image, heap->dblk_size);
+
+                /* Build free list */
+                if(H5HL__fl_deserialize(heap) < 0)
+                    HGOTO_ERROR(H5E_HEAP, H5E_CANTINIT, NULL, "can't initialize free list")
             } /* end if */
             else {
-                /* Read the local heap data block directly into buffer */
-                if(H5F_block_read(f, H5FD_MEM_LHEAP, heap->dblk_addr, heap->dblk_size, dxpl_id, heap->dblk_image) < 0)
-                    HGOTO_ERROR(H5E_HEAP, H5E_READERROR, NULL, "unable to read heap data")
-            } /* end else */
-
-            /* Build free list */
-            if(H5HL__fl_deserialize(heap) < 0)
-                HGOTO_ERROR(H5E_HEAP, H5E_CANTINIT, NULL, "can't initialize free list")
+		/* the supplied buffer is too small -- We have already made note
+                 * of the correct size, so simply return success.  H5C_load_entry()
+                 * will notice the size discrepency, and re-try the load.
+                 */
+
+                /* Make certain that this is the first try ... */
+                HDassert(!udata->made_attempt);
+
+                /* ... and mark the udata so that we know that we have used up
+                 * our first try.
+                 */
+                udata->made_attempt = TRUE;
+	    } /* end else */
         } /* end if */
-        else
-            /* Note that the heap should _NOT_ be a single object in the cache */
+        else {
+            /* Note that the heap should _NOT_ be a single 
+             * object in the cache 
+             */
             heap->single_cache_obj = FALSE;
+
+	} /* end else */
     } /* end if */
 
+    /* Set flag to indicate prefix from loaded from file */
+    udata->loaded = TRUE;
+
     /* Set return value */
     ret_value = prfx;
 
@@ -375,273 +432,269 @@ done:
     } /* end if */
 
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5HL_prefix_load() */
+} /* end H5HL__cache_prefix_deserialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HL_prefix_flush
+ * Function:    H5HL__cache_prefix_image_len
  *
- * Purpose:	Flushes a heap from memory to disk if it's dirty.  Optionally
- *		deletes the heap from memory.
+ * Purpose:	Return the on disk image size of a local heap prefix to the 
+ *		metadata cache via the image_len.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
  *
- * Programmer:	Robb Matzke
- *		matzke@llnl.gov
- *		Jul 17 1997
+ * Programmer:  John Mainzer
+ *              6/21/14
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5HL_prefix_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr,
-    void *thing, unsigned H5_ATTR_UNUSED *flags_ptr)
+H5HL__cache_prefix_image_len(const void *_thing, size_t *image_len,
+    hbool_t H5_ATTR_UNUSED *compressed_ptr, size_t H5_ATTR_UNUSED *compressed_image_len_ptr)
 {
-    H5HL_prfx_t *prfx = (H5HL_prfx_t *)thing;   /* Local heap prefix to flush */
-    H5WB_t *wb = NULL;                  /* Wrapped buffer for heap data */
-    uint8_t heap_buf[H5HL_SPEC_READ_SIZE]; /* Buffer for heap */
-    herr_t ret_value = SUCCEED;         /* Return value */
+    const H5HL_prfx_t *prfx = (const H5HL_prfx_t *)_thing;  /* Pointer to local heap prefix to query */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC_NOERR
 
-    /* check arguments */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
+    /* Check arguments */
     HDassert(prfx);
+    HDassert(prfx->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(prfx->cache_info.type == H5AC_LHEAP_PRFX);
+    HDassert(image_len);
 
-    if(prfx->cache_info.is_dirty) {
-        H5HL_t *heap = prfx->heap; /* Pointer to the local heap */
-        uint8_t *buf;           /* Pointer to heap buffer */
-        size_t buf_size;        /* Size of buffer for encoding & writing heap info */
-        uint8_t *p;             /* Pointer into raw data buffer */
-
-        /* Wrap the local buffer for serialized heap info */
-        if(NULL == (wb = H5WB_wrap(heap_buf, sizeof(heap_buf))))
-            HGOTO_ERROR(H5E_HEAP, H5E_CANTINIT, FAIL, "can't wrap buffer")
-
-        /* Compute the size of the buffer to encode & write */
-        buf_size = heap->prfx_size;
-        if(heap->single_cache_obj)
-            buf_size += heap->dblk_size;
-
-        /* Get a pointer to a buffer that's large enough for serialized heap */
-        if(NULL == (buf = (uint8_t *)H5WB_actual(wb, buf_size)))
-            HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, FAIL, "can't get actual buffer")
-
-        /* Update the free block value from the free list */
-        heap->free_block = heap->freelist ? heap->freelist->offset : H5HL_FREE_NULL;
-
-        /* Serialize the heap prefix */
-        p = buf;
-        HDmemcpy(p, H5HL_MAGIC, (size_t)H5_SIZEOF_MAGIC);
-        p += H5_SIZEOF_MAGIC;
-        *p++ = H5HL_VERSION;
-        *p++ = 0;	/*reserved*/
-        *p++ = 0;	/*reserved*/
-        *p++ = 0;	/*reserved*/
-        H5F_ENCODE_LENGTH_LEN(p, heap->dblk_size, heap->sizeof_size);
-        H5F_ENCODE_LENGTH_LEN(p, heap->free_block, heap->sizeof_size);
-        H5F_addr_encode_len(heap->sizeof_addr, &p, heap->dblk_addr);
-
-        /* Check if the local heap is a single object in cache */
-        if(heap->single_cache_obj) {
-            if((size_t)(p - buf) < heap->prfx_size) {
-                size_t gap;         /* Size of gap between prefix and data block */
-
-                /* Set p to the start of the data block.  This is necessary because
-                 * there may be a gap between the used portion of the prefix and the
-                 * data block due to alignment constraints. */
-                gap = heap->prfx_size - (size_t)(p - buf);
-                HDmemset(p, 0, gap);
-                p += gap;
-            } /* end if */
-
-            /* Serialize the free list into the heap data's image */
-            H5HL__fl_serialize(heap);
-
-            /* Copy the heap data block into the cache image */
-            HDmemcpy(p, heap->dblk_image, heap->dblk_size);
-        } /* end if */
-
-        /* Write the prefix [and possibly the data block] to the file */
-        if(H5F_block_write(f, H5FD_MEM_LHEAP, addr, buf_size, dxpl_id, buf) < 0)
-            HGOTO_ERROR(H5E_HEAP, H5E_WRITEERROR, FAIL, "unable to write heap header and data to file")
+    /* Set the prefix's size */
+    *image_len = prfx->heap->prfx_size;
 
-	prfx->cache_info.is_dirty = FALSE;
-    } /* end if */
+    /* If the heap is stored as a single object, add in the 
+     * data block size also 
+     */
+    if(prfx->heap->single_cache_obj)
+        *image_len += prfx->heap->dblk_size;
 
-    /* Should we destroy the memory version? */
-    if(destroy)
-        if(H5HL_prefix_dest(f, prfx) < 0)
-	    HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to destroy local heap prefix")
 
-done:
-    /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-        HDONE_ERROR(H5E_HEAP, H5E_CLOSEERROR, FAIL, "can't close wrapped buffer")
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5HL__cache_prefix_image_len() */
 
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5HL_prefix_flush() */
+/****************************************/
+/* no H5HL_cache_prefix_pre_serialize() */
+/****************************************/
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HL_prefix_dest
+ * Function:    H5HL__cache_prefix_serialize
  *
- * Purpose:	Destroys a heap prefix in memory.
+ * Purpose:	Given a pointer to an instance of H5HL_prfx_t and an 
+ *		appropriately sized buffer, serialize the contents of the 
+ *		instance for writing to disk, and copy the serialized data 
+ *		into the buffer.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Jan 15 2003
+ * Programmer:  John Mainzer
+ *              7/21/14
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5HL_prefix_dest(H5F_t *f, void *thing)
+H5HL__cache_prefix_serialize(const H5F_t *f, void *_image, size_t len,
+    void *_thing)
 {
-    H5HL_prfx_t *prfx = (H5HL_prfx_t *)thing;   /* Local heap prefix to destroy */
-    herr_t ret_value = SUCCEED;         /* Return value */
+    H5HL_prfx_t *prfx = (H5HL_prfx_t *)_thing;  /* Pointer to local heap prefix to query */
+    H5HL_t      *heap;          /* Pointer to the local heap */
+    uint8_t     *image = (uint8_t *)_image;     /* Pointer into image buffer */
+    size_t       buf_size;      /* expected size of the image buffer */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC_NOERR
 
-    /* check arguments */
+    /* Check arguments */
+    HDassert(f);
+    HDassert(image);
     HDassert(prfx);
-    HDassert(prfx->heap);
+    HDassert(prfx->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(prfx->cache_info.type == H5AC_LHEAP_PRFX);
     HDassert(H5F_addr_eq(prfx->cache_info.addr, prfx->heap->prfx_addr));
+    HDassert(prfx->heap);
 
-    /* Verify that entry is clean */
-    HDassert(prfx->cache_info.is_dirty == FALSE);
+    /* Get the pointer to the heap */
+    heap = prfx->heap;
+    HDassert(heap);
 
-    /* If we're going to free the space on disk, the address must be valid */
-    HDassert(!prfx->cache_info.free_file_space_on_destroy || H5F_addr_defined(prfx->cache_info.addr));
+    /* Compute the buffer size */
+    buf_size = heap->prfx_size;
+    if(heap->single_cache_obj)
+        buf_size += heap->dblk_size;
+    HDassert(len == buf_size);
+
+    /* Update the free block value from the free list */
+    heap->free_block = heap->freelist ? heap->freelist->offset : H5HL_FREE_NULL;
+
+    /* Serialize the heap prefix */
+    HDmemcpy(image, H5HL_MAGIC, (size_t)H5_SIZEOF_MAGIC);
+    image += H5_SIZEOF_MAGIC;
+    *image++ = H5HL_VERSION;
+    *image++ = 0;       /*reserved*/
+    *image++ = 0;       /*reserved*/
+    *image++ = 0;       /*reserved*/
+    H5F_ENCODE_LENGTH_LEN(image, heap->dblk_size, heap->sizeof_size);
+    H5F_ENCODE_LENGTH_LEN(image, heap->free_block, heap->sizeof_size);
+    H5F_addr_encode_len(heap->sizeof_addr, &image, heap->dblk_addr);
+
+    /* Check if the local heap is a single object in cache */
+    if(heap->single_cache_obj) {
+        if((size_t)(image - (uint8_t *)_image) < heap->prfx_size) {
+            size_t gap;         /* Size of gap between prefix and data block */
+
+            /* Set image to the start of the data block.  This is necessary 
+             * because there may be a gap between the used portion of 
+             * the prefix and the data block due to alignment constraints. 
+             */
+            gap = heap->prfx_size - (size_t)(image - (uint8_t *)_image);
+            HDmemset(image, 0, gap);
+            image += gap;
+        } /* end if */
 
-    /* Check for freeing file space for local heap prefix */
-    if(prfx->cache_info.free_file_space_on_destroy) {
-        hsize_t free_size;       /* Size of region to free in file */
+        /* Serialize the free list into the heap data's image */
+        H5HL__fl_serialize(heap);
 
-        /* Compute size to free for later */
-        free_size = prfx->heap->prfx_size;
-        if(prfx->heap->single_cache_obj)
-            free_size += prfx->heap->dblk_size;
+        /* Copy the heap data block into the cache image */
+        HDmemcpy(image, heap->dblk_image, heap->dblk_size);
 
-        /* Free the local heap prefix [and possible the data block] on disk */
-        /* (XXX: Nasty usage of internal DXPL value! -QAK) */
-        if(H5MF_xfree(f, H5FD_MEM_LHEAP, H5AC_dxpl_id, prfx->cache_info.addr, free_size) < 0)
-            HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to free local heap prefix")
+        /* Sanity check */
+        HDassert((size_t)(image - (uint8_t *)_image) + heap->dblk_size == len);
     } /* end if */
+    else {
+        /* Sanity check */
+        HDassert((size_t)(image - (uint8_t *)_image) <= len);
 
-    /* Destroy local heap prefix */
-    if(H5HL_prfx_dest(prfx) < 0)
-        HGOTO_ERROR(H5E_HEAP, H5E_CANTRELEASE, FAIL, "can't destroy local heap prefix")
+#ifdef H5_CLEAR_MEMORY
+        /* Clear rest of local heap */
+        HDmemset(image, 0, len - (size_t)(image - (uint8_t *)_image));
+#endif /* H5_CLEAR_MEMORY */
+    } /* end else */
 
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5HL_prefix_dest() */
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5HL__cache_prefix_serialize() */
+
+/******************************************/
+/* no H5HL_cache_prefix_notify() function */
+/******************************************/
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HL_prefix_clear
+ * Function:    H5HL__cache_prefix_free_icr
  *
- * Purpose:	Mark a local heap prefix in memory as non-dirty.
+ * Purpose:	Free the supplied in core representation of a local heap 
+ *		prefix.
  *
- * Return:	Non-negative on success/Negative on failure
+ *		Note that this function handles the partially initialize prefix 
+ *		from a failed speculative load attempt.  See comments below for 
+ *		details.
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Mar 20 2003
+ * Note:	The metadata cache sets the object's cache_info.magic to
+ *		H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC before calling a free_icr
+ *		callback (checked in assert).
+ *
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
+ *
+ * Programmer:  John Mainzer
+ *              6/21/14
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5HL_prefix_clear(H5F_t H5_ATTR_UNUSED *f, void *thing, hbool_t destroy)
+H5HL__cache_prefix_free_icr(void *_thing)
 {
-    H5HL_prfx_t *prfx = (H5HL_prfx_t *)thing;   /* The local heap prefix to operate on */
-    herr_t ret_value = SUCCEED;         /* Return value */
+    H5HL_prfx_t *prfx = (H5HL_prfx_t *)_thing;  /* Pointer to local heap prefix to query */
+    herr_t       ret_value = SUCCEED;    /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
-    /* check arguments */
+    /* Check arguments */
     HDassert(prfx);
+    HDassert(prfx->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC);
+    HDassert(prfx->cache_info.type == H5AC_LHEAP_PRFX);
+    HDassert(H5F_addr_eq(prfx->cache_info.addr, prfx->heap->prfx_addr));
 
-    /* Mark heap prefix as clean */
-    prfx->cache_info.is_dirty = FALSE;
-
-    if(destroy)
-        if(H5HL_prefix_dest(f, prfx) < 0)
-	    HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to destroy local heap prefix")
+    /* Destroy local heap prefix */
+    if(H5HL_prfx_dest(prfx) < 0)
+        HGOTO_ERROR(H5E_HEAP, H5E_CANTRELEASE, FAIL, "can't destroy local heap prefix")
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5HL_prefix_clear() */
+} /* end H5HL__cache_prefix_free_icr() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HL_prefix_size
+ * Function:    H5HL__cache_datablock_get_load_size()
  *
- * Purpose:	Compute the size in bytes of the heap prefix on disk,
- *              and return it in *len_ptr.  On failure, the value of *len_ptr
- *              is undefined.
+ * Purpose:	Tell the metadata cache how large a buffer to read from 
+ *		file when loading a datablock.  In this case, we simply lookup
+ *		the correct value in the user data, and return it in *image_len.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
  *
- * Programmer:	John Mainzer
- *		5/13/04
+ * Programmer:  John Mainzer
+ *              6/21/14
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5HL_prefix_size(const H5F_t H5_ATTR_UNUSED *f, const void *thing, size_t *size_ptr)
+H5HL__cache_datablock_get_load_size(const void *_udata, size_t *image_len)
 {
-    const H5HL_prfx_t *prfx = (const H5HL_prfx_t *)thing;   /* Pointer to local heap prefix to query */
+    const H5HL_cache_dblk_ud_t *udata = (const H5HL_cache_dblk_ud_t *)_udata; /* User data for callback */
 
-    FUNC_ENTER_NOAPI_NOINIT_NOERR
-
-    /* check arguments */
-    HDassert(prfx);
-    HDassert(prfx->heap);
-    HDassert(size_ptr);
+    FUNC_ENTER_STATIC_NOERR
 
-    /* Calculate size of prefix in cache */
-    *size_ptr = prfx->heap->prfx_size;
+    /* Check arguments */
+    HDassert(udata);
+    HDassert(udata->heap);
+    HDassert(udata->heap->dblk_size > 0);
+    HDassert(image_len);
 
-    /* If the heap is stored as a single object, add in the data block size also */
-    if(prfx->heap->single_cache_obj)
-        *size_ptr += prfx->heap->dblk_size;
+    *image_len = udata->heap->dblk_size;
 
     FUNC_LEAVE_NOAPI(SUCCEED)
-} /* H5HL_prefix_size() */
+} /* end H5HL__cache_datablock_get_load_size() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HL_datablock_load
+ * Function:    H5HL__cache_datablock_deserialize
  *
- * Purpose:	Loads a local heap data block from disk.
+ * Purpose:	Given a buffer containing the on disk image of a local 
+ *		heap data block, deserialize it, load its contents into a newly allocated
+ *		instance of H5HL_dblk_t, and return a pointer to the new instance.
  *
- * Return:	Success:	Ptr to a local heap data block memory data structure.
- *		Failure:	NULL
+ * Return:      Success:        Pointer to in core representation
+ *              Failure:        NULL
  *
- * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Jan  5 2010
+ * Programmer:  John Mainzer
+ *              6/21/14
  *
  *-------------------------------------------------------------------------
  */
 static void *
-H5HL_datablock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
+H5HL__cache_datablock_deserialize(const void *image, size_t len, void *_udata,
+    hbool_t H5_ATTR_UNUSED *dirty)
 {
-    H5HL_dblk_t *dblk = NULL;       /* Local heap data block deserialized */
-    H5HL_cache_dblk_ud_t *udata = (H5HL_cache_dblk_ud_t *)_udata;       /* User data for callback */
-    H5HL_dblk_t *ret_value;         /* Return value */
+    H5HL_dblk_t          *dblk = NULL;  /* Local heap data block deserialized */
+    H5HL_cache_dblk_ud_t *udata = (H5HL_cache_dblk_ud_t *)_udata; /* User data for callback */
+    void *                ret_value;    /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
     /* Check arguments */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
+    HDassert(image);
+    HDassert(len > 0);
     HDassert(udata);
     HDassert(udata->heap);
+    HDassert(udata->heap->dblk_size == len);
     HDassert(!udata->heap->single_cache_obj);
     HDassert(NULL == udata->heap->dblk);
+    HDassert(dirty);
 
     /* Allocate space in memory for the heap data block */
     if(NULL == (dblk = H5HL_dblk_new(udata->heap)))
@@ -653,9 +706,8 @@ H5HL_datablock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
         if(NULL == (udata->heap->dblk_image = H5FL_BLK_MALLOC(lheap_chunk, udata->heap->dblk_size)))
             HGOTO_ERROR(H5E_HEAP, H5E_CANTALLOC, NULL, "can't allocate data block image buffer")
 
-        /* Read local heap data block */
-        if(H5F_block_read(f, H5FD_MEM_LHEAP, udata->heap->dblk_addr, udata->heap->dblk_size, dxpl_id, udata->heap->dblk_image) < 0)
-            HGOTO_ERROR(H5E_HEAP, H5E_READERROR, NULL, "unable to read local heap data block")
+        /* copy the datablock from the read buffer */
+        HDmemcpy(udata->heap->dblk_image, image, len);
 
         /* Build free list */
         if(H5HL__fl_deserialize(udata->heap) < 0)
@@ -675,180 +727,134 @@ done:
             HDONE_ERROR(H5E_HEAP, H5E_CANTRELEASE, NULL, "unable to destroy local heap data block")
 
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5HL_datablock_load() */
+} /* end H5HL__cache_datablock_deserialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HL_datablock_flush
+ * Function:    H5HL__cache_datablock_image_len
  *
- * Purpose:	Flushes a heap's data block from memory to disk if it's dirty.
- *              Optionally deletes the heap data block from memory.
+ * Purpose:	Return the size of the on disk image of the datablock.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
  *
- * Programmer:	Robb Matzke
- *		matzke@llnl.gov
- *		Jul 17 1997
+ * Programmer:  John Mainzer
+ *              6/21/14
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5HL_datablock_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr,
-    void *_thing, unsigned H5_ATTR_UNUSED * flags_ptr)
+H5HL__cache_datablock_image_len(const void *_thing, size_t *image_len,
+    hbool_t H5_ATTR_UNUSED *compressed_ptr, size_t H5_ATTR_UNUSED *compressed_image_len_ptr)
 {
-    H5HL_dblk_t *dblk = (H5HL_dblk_t *)_thing; /* Pointer to the local heap data block */
-    herr_t ret_value = SUCCEED;         /* Return value */
+    const H5HL_dblk_t *dblk = (const H5HL_dblk_t *)_thing;    /* Pointer to the local heap data block */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC_NOERR
 
-    /* check arguments */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
+    /* Check arguments */
     HDassert(dblk);
+    HDassert(dblk->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(dblk->cache_info.type == H5AC_LHEAP_DBLK);
     HDassert(dblk->heap);
-    HDassert(!dblk->heap->single_cache_obj);
-
-    if(dblk->cache_info.is_dirty) {
-        H5HL_t *heap = dblk->heap;      /* Pointer to the local heap */
+    HDassert(dblk->heap->dblk_size > 0);
+    HDassert(image_len);
 
-        /* Update the free block value from the free list */
-        heap->free_block = heap->freelist ? heap->freelist->offset : H5HL_FREE_NULL;
+    *image_len = dblk->heap->dblk_size;
 
-        /* Serialize the free list into the heap data's image */
-        H5HL__fl_serialize(heap);
-
-        /* Write the data block to the file */
-        if(H5F_block_write(f, H5FD_MEM_LHEAP, heap->dblk_addr, heap->dblk_size, dxpl_id, heap->dblk_image) < 0)
-            HGOTO_ERROR(H5E_HEAP, H5E_WRITEERROR, FAIL, "unable to write heap data block to file")
-
-	dblk->cache_info.is_dirty = FALSE;
-    } /* end if */
-
-    /* Should we destroy the memory version? */
-    if(destroy)
-        if(H5HL_datablock_dest(f, dblk) < 0)
-	    HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to destroy local heap data block")
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5HL__cache_datablock_image_len() */
 
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5HL_datablock_flush() */
+/*******************************************/
+/* no H5HL_cache_datablock_pre_serialize() */
+/*******************************************/
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HL_datablock_dest
+ * Function:    H5HL__cache_datablock_serialize
  *
- * Purpose:	Destroys a local heap data block in memory.
+ * Purpose:	Serialize the supplied datablock, and copy the serialized
+ *		image into the supplied image buffer.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Jan 15 2003
+ * Programmer:  John Mainzer
+ *              6/21/14
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5HL_datablock_dest(H5F_t *f, void *_thing)
+H5HL__cache_datablock_serialize(const H5F_t *f, void *image, size_t len,
+    void *_thing)
 {
-    H5HL_dblk_t *dblk = (H5HL_dblk_t *)_thing; /* Pointer to the local heap data block */
-    herr_t ret_value = SUCCEED;         /* Return value */
+    H5HL_t      *heap;          /* Pointer to the local heap */
+    H5HL_dblk_t *dblk = (H5HL_dblk_t *)_thing;  /* Pointer to the local heap data block */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC_NOERR
 
     /* Check arguments */
+    HDassert(f);
+    HDassert(image);
     HDassert(dblk);
+    HDassert(dblk->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(dblk->cache_info.type == H5AC_LHEAP_DBLK);
     HDassert(dblk->heap);
-    HDassert(!dblk->heap->single_cache_obj);
-    HDassert(H5F_addr_eq(dblk->cache_info.addr, dblk->heap->dblk_addr));
+    heap = dblk->heap;
+    HDassert(heap->dblk_size == len);
+    HDassert(!heap->single_cache_obj);
 
-    /* Verify that entry is clean */
-    HDassert(dblk->cache_info.is_dirty == FALSE);
+    /* Update the free block value from the free list */
+    heap->free_block = heap->freelist ? heap->freelist->offset : H5HL_FREE_NULL;
 
-    /* If we're going to free the space on disk, the address must be valid */
-    HDassert(!dblk->cache_info.free_file_space_on_destroy || H5F_addr_defined(dblk->cache_info.addr));
+    /* Serialize the free list into the heap data's image */
+    H5HL__fl_serialize(heap);
 
-    /* Check for freeing file space for local heap data block */
-    if(dblk->cache_info.free_file_space_on_destroy) {
-        /* Free the local heap data block on disk */
-        /* (XXX: Nasty usage of internal DXPL value! -QAK) */
-        if(H5MF_xfree(f, H5FD_MEM_LHEAP, H5AC_dxpl_id, dblk->cache_info.addr, (hsize_t)dblk->heap->dblk_size) < 0)
-            HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to free local heap data block")
-    } /* end if */
+    /* Copy the heap's data block into the cache's image */
+    HDmemcpy(image, heap->dblk_image, heap->dblk_size);
 
-    /* Destroy local heap data block */
-    if(H5HL_dblk_dest(dblk) < 0)
-        HGOTO_ERROR(H5E_HEAP, H5E_CANTRELEASE, FAIL, "can't destroy local heap data block")
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5HL__cache_datablock_serialize() */
 
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5HL_datablock_dest() */
+/*********************************************/
+/* no H5HL_cache_datablock_notify() function */
+/*********************************************/
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HL_datablock_clear
+ * Function:    H5HL__cache_datablock_free_icr
  *
- * Purpose:	Mark a local heap data block in memory as non-dirty.
+ * Purpose:	Free the in memory representation of the supplied local heap data block.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Note:	The metadata cache sets the object's cache_info.magic to
+ *		H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC before calling a free_icr
+ *		callback (checked in assert).
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Mar 20 2003
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
+ *
+ * Programmer:  John Mainzer
+ *              6/21/14
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5HL_datablock_clear(H5F_t *f, void *_thing, hbool_t destroy)
+H5HL__cache_datablock_free_icr(void *_thing)
 {
     H5HL_dblk_t *dblk = (H5HL_dblk_t *)_thing; /* Pointer to the local heap data block */
-    herr_t ret_value = SUCCEED;         /* Return value */
+    herr_t       ret_value = SUCCEED;    /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
     /* Check arguments */
     HDassert(dblk);
+    HDassert(dblk->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC);
+    HDassert(dblk->cache_info.type == H5AC_LHEAP_DBLK);
 
-    /* Mark local heap data block as clean */
-    dblk->cache_info.is_dirty = FALSE;
-
-    if(destroy)
-        if(H5HL_datablock_dest(f, dblk) < 0)
-	    HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to destroy local heap data block")
+    /* Destroy the data block */
+    if(H5HL_dblk_dest(dblk) < 0)
+        HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to destroy local heap data block")
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5HL_datablock_clear() */
-
-
-/*-------------------------------------------------------------------------
- * Function:	H5HL_datablock_size
- *
- * Purpose:	Compute the size in bytes of the local heap data block on disk,
- *              and return it in *len_ptr.  On failure, the value of *len_ptr
- *              is undefined.
- *
- * Return:	Non-negative on success/Negative on failure
- *
- * Programmer:	John Mainzer
- *		5/13/04
- *
- *-------------------------------------------------------------------------
- */
-static herr_t
-H5HL_datablock_size(const H5F_t H5_ATTR_UNUSED *f, const void *_thing, size_t *size_ptr)
-{
-    const H5HL_dblk_t *dblk = (const H5HL_dblk_t *)_thing; /* Pointer to the local heap data block */
-
-    FUNC_ENTER_NOAPI_NOINIT_NOERR
-
-    /* check arguments */
-    HDassert(dblk);
-    HDassert(dblk->heap);
-    HDassert(size_ptr);
-
-    /* Set size of data block in cache */
-    *size_ptr = dblk->heap->dblk_size;
-
-    FUNC_LEAVE_NOAPI(SUCCEED)
-} /* H5HL_datablock_size() */
+} /* end H5HL__cache_datablock_free_icr() */
 
diff --git a/src/H5HLdbg.c b/src/H5HLdbg.c
index 4ac22b8..edddd65 100644
--- a/src/H5HLdbg.c
+++ b/src/H5HLdbg.c
@@ -69,7 +69,7 @@ H5HL_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE * stream, int indent, int
     HDassert(indent >= 0);
     HDassert(fwidth >= 0);
 
-    if(NULL == (h = (H5HL_t *)H5HL_protect(f, dxpl_id, addr, H5AC_READ)))
+    if(NULL == (h = (H5HL_t *)H5HL_protect(f, dxpl_id, addr, H5AC__READ_ONLY_FLAG)))
         HGOTO_ERROR(H5E_HEAP, H5E_CANTLOAD, FAIL, "unable to load heap")
 
     HDfprintf(stream, "%*sLocal Heap...\n", indent, "");
diff --git a/src/H5HLpkg.h b/src/H5HLpkg.h
index 880cc05..75c9959 100644
--- a/src/H5HLpkg.h
+++ b/src/H5HLpkg.h
@@ -122,12 +122,16 @@ struct H5HL_prfx_t {
 /* Callback information for loading local heap prefix from disk */
 typedef struct H5HL_cache_prfx_ud_t {
     /* Downwards */
+    hbool_t made_attempt;               /* Whether the deserialize routine */
+                                        /* was already attempted */
     size_t sizeof_size;                 /* Size of file sizes */
     size_t sizeof_addr;                 /* Size of file addresses */
     haddr_t prfx_addr;                  /* Address of prefix */
     size_t sizeof_prfx;                 /* Size of heap prefix */
 
     /* Upwards */
+    hbool_t loaded;                     /* Whether prefix was loaded */
+                                        /* from file */
 } H5HL_cache_prfx_ud_t;
 
 /* Callback information for loading local heap data block from disk */
diff --git a/src/H5HLprivate.h b/src/H5HLprivate.h
index 0b044b6..3035689 100644
--- a/src/H5HLprivate.h
+++ b/src/H5HLprivate.h
@@ -61,7 +61,7 @@ typedef struct H5HL_t H5HL_t;
  * Library prototypes...
  */
 H5_DLL herr_t H5HL_create(H5F_t *f, hid_t dxpl_id, size_t size_hint, haddr_t *addr/*out*/);
-H5_DLL H5HL_t *H5HL_protect(H5F_t *f, hid_t dxpl_id, haddr_t addr, H5AC_protect_t rw);
+H5_DLL H5HL_t *H5HL_protect(H5F_t *f, hid_t dxpl_id, haddr_t addr, unsigned flags);
 H5_DLL void *H5HL_offset_into(const H5HL_t *heap, size_t offset);
 H5_DLL herr_t H5HL_remove(H5F_t *f, hid_t dxpl_id, H5HL_t *heap, size_t offset,
     size_t size);
diff --git a/src/H5O.c b/src/H5O.c
index 22086fa..6b9852b 100644
--- a/src/H5O.c
+++ b/src/H5O.c
@@ -44,6 +44,9 @@
 #include "H5Iprivate.h"		/* IDs			  		*/
 #include "H5Lprivate.h"		/* Links				*/
 #include "H5MFprivate.h"	/* File memory management		*/
+#ifdef H5O_ENABLE_BOGUS
+#include "H5MMprivate.h"	/* Memory management			*/
+#endif /* H5O_ENABLE_BOGUS */
 #include "H5Opkg.h"             /* Object headers			*/
 #include "H5SMprivate.h"        /* Shared object header messages        */
 
@@ -196,10 +199,10 @@ H5O_init_interface(void)
     FUNC_ENTER_NOAPI_NOINIT_NOERR
 
     /* H5O interface sanity checks */
-    HDassert(H5O_MSG_TYPES == NELMTS(H5O_msg_class_g));
-    HDassert(sizeof(H5O_fheap_id_t) == H5O_FHEAP_ID_LEN);
+    HDcompile_assert(H5O_MSG_TYPES == NELMTS(H5O_msg_class_g));
+    HDcompile_assert(sizeof(H5O_fheap_id_t) == H5O_FHEAP_ID_LEN);
 
-    HDassert(H5O_UNKNOWN_ID < H5O_MSG_TYPES);
+    HDcompile_assert(H5O_UNKNOWN_ID < H5O_MSG_TYPES);
 
     FUNC_LEAVE_NOAPI(SUCCEED)
 } /* end H5O_init_interface() */
@@ -1652,7 +1655,7 @@ done:
  *-------------------------------------------------------------------------
  */
 H5O_t *
-H5O_protect(const H5O_loc_t *loc, hid_t dxpl_id, H5AC_protect_t prot)
+H5O_protect(const H5O_loc_t *loc, hid_t dxpl_id, unsigned prot_flags)
 {
     H5O_t *oh = NULL;           /* Object header protected */
     H5O_cache_ud_t udata;       /* User data for protecting object header */
@@ -1666,13 +1669,16 @@ H5O_protect(const H5O_loc_t *loc, hid_t dxpl_id, H5AC_protect_t prot)
     HDassert(loc);
     HDassert(loc->file);
 
+    /* prot_flags may only contain the H5AC__READ_ONLY_FLAG */
+    HDassert((prot_flags & (unsigned)(~H5AC__READ_ONLY_FLAG)) == 0);
+
     /* Check for valid address */
     if(!H5F_addr_defined(loc->addr))
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, NULL, "address undefined")
 
     /* Check for write access on the file */
     file_intent = H5F_INTENT(loc->file);
-    if((prot == H5AC_WRITE) && (0 == (file_intent & H5F_ACC_RDWR)))
+    if((0 == (prot_flags & H5AC__READ_ONLY_FLAG)) && (0 == (file_intent & H5F_ACC_RDWR)))
 	HGOTO_ERROR(H5E_OHDR, H5E_BADVALUE, NULL, "no write intent on file")
 
     /* Construct the user data for protect callback */
@@ -1688,7 +1694,7 @@ H5O_protect(const H5O_loc_t *loc, hid_t dxpl_id, H5AC_protect_t prot)
     udata.common.addr = loc->addr;
 
     /* Lock the object header into the cache */
-    if(NULL == (oh = (H5O_t *)H5AC_protect(loc->file, dxpl_id, H5AC_OHDR, loc->addr, &udata, prot)))
+    if(NULL == (oh = (H5O_t *)H5AC_protect(loc->file, dxpl_id, H5AC_OHDR, loc->addr, &udata, prot_flags)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, NULL, "unable to load object header")
 
     /* Check if there are any continuation messages to process */
@@ -1725,7 +1731,7 @@ H5O_protect(const H5O_loc_t *loc, hid_t dxpl_id, H5AC_protect_t prot)
             /* (which adds to the object header) */
             chk_udata.common.addr = cont_msg_info.msgs[curr_msg].addr;
             chk_udata.size = cont_msg_info.msgs[curr_msg].size;
-            if(NULL == (chk_proxy = (H5O_chunk_proxy_t *)H5AC_protect(loc->file, dxpl_id, H5AC_OHDR_CHK, cont_msg_info.msgs[curr_msg].addr, &chk_udata, prot)))
+            if(NULL == (chk_proxy = (H5O_chunk_proxy_t *)H5AC_protect(loc->file, dxpl_id, H5AC_OHDR_CHK, cont_msg_info.msgs[curr_msg].addr, &chk_udata, prot_flags)))
                 HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, NULL, "unable to load object header chunk")
 
             /* Sanity check */
@@ -1769,7 +1775,7 @@ H5O_protect(const H5O_loc_t *loc, hid_t dxpl_id, H5AC_protect_t prot)
             /* (object header will have been marked dirty during protect, if we
              *  have write access -QAK)
              */
-            if(prot != H5AC_WRITE)
+            if((prot_flags & H5AC__READ_ONLY_FLAG) != 0)
                 oh->prefix_modified = TRUE;
 #ifndef NDEBUG
             else {
@@ -1787,7 +1793,7 @@ H5O_protect(const H5O_loc_t *loc, hid_t dxpl_id, H5AC_protect_t prot)
         } /* end if */
 
         /* Check for any messages that were modified while being read in */
-        if(udata.common.mesgs_modified && prot != H5AC_WRITE)
+        if(udata.common.mesgs_modified && (0 == (prot_flags & H5AC__READ_ONLY_FLAG)))
             oh->mesgs_modified = TRUE;
 
         /* Reset the field that contained chunk 0's size during speculative load */
@@ -1797,7 +1803,7 @@ H5O_protect(const H5O_loc_t *loc, hid_t dxpl_id, H5AC_protect_t prot)
     /* Take care of loose ends for modifications made while bringing in the
      *      object header & chunks.
      */
-    if(prot == H5AC_WRITE) {
+    if(0 == (prot_flags & H5AC__READ_ONLY_FLAG)) {
         /* Check for the object header prefix being modified somehow */
         /* (usually through updating the # of object header messages) */
         if(oh->prefix_modified) {
@@ -1883,7 +1889,7 @@ H5O_pin(const H5O_loc_t *loc, hid_t dxpl_id)
     HDassert(loc);
 
     /* Get header */
-    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC_WRITE)))
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__NO_FLAGS_SET)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, NULL, "unable to protect object header")
 
     /* Increment the reference count on the object header */
@@ -2096,7 +2102,7 @@ H5O_touch(const H5O_loc_t *loc, hbool_t force, hid_t dxpl_id)
     HDassert(loc);
 
     /* Get the object header */
-    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC_WRITE)))
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__NO_FLAGS_SET)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to load object header")
 
     /* Create/Update the modification time message */
@@ -2212,7 +2218,7 @@ H5O_delete(H5F_t *f, hid_t dxpl_id, haddr_t addr)
     loc.holding_file = FALSE;
 
     /* Get the object header information */
-    if(NULL == (oh = H5O_protect(&loc, dxpl_id, H5AC_WRITE)))
+    if(NULL == (oh = H5O_protect(&loc, dxpl_id, H5AC__NO_FLAGS_SET)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to load object header")
 
     /* Delete object */
@@ -2296,7 +2302,7 @@ H5O_obj_type(const H5O_loc_t *loc, H5O_type_t *obj_type, hid_t dxpl_id)
     FUNC_ENTER_NOAPI_TAG(dxpl_id, loc->addr, FAIL)
 
     /* Load the object header */
-    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC_READ)))
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to load object header")
 
     /* Retrieve the type of the object */
@@ -2374,7 +2380,7 @@ H5O_obj_class(const H5O_loc_t *loc, hid_t dxpl_id)
     FUNC_ENTER_NOAPI_NOINIT_TAG(dxpl_id, loc->addr, NULL)
 
     /* Load the object header */
-    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC_READ)))
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, NULL, "unable to load object header")
 
     /* Test whether entry qualifies as a particular type of object */
@@ -2671,7 +2677,7 @@ H5O_get_hdr_info(const H5O_loc_t *loc, hid_t dxpl_id, H5O_hdr_info_t *hdr)
     HDmemset(hdr, 0, sizeof(*hdr));
 
     /* Get the object header */
-    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC_READ)))
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTLOAD, FAIL, "unable to load object header")
 
     /* Get the information for the object header */
@@ -2795,7 +2801,7 @@ H5O_get_info(const H5O_loc_t *loc, hid_t dxpl_id, hbool_t want_ih_info,
     HDassert(oinfo);
 
     /* Get the object header */
-    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC_READ)))
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to load object header")
 
     /* Reset the object info structure */
@@ -2916,7 +2922,7 @@ H5O_get_create_plist(const H5O_loc_t *loc, hid_t dxpl_id, H5P_genplist_t *oc_pli
     HDassert(oc_plist);
 
     /* Get the object header */
-    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC_READ)))
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to load object header")
 
     /* Set property values, if they were used for the object */
@@ -2971,7 +2977,7 @@ H5O_get_nlinks(const H5O_loc_t *loc, hid_t dxpl_id, hsize_t *nlinks)
     HDassert(nlinks);
 
     /* Get the object header */
-    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC_READ)))
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to load object header")
 
     /* Retrieve the # of link messages seen when the object header was loaded */
@@ -3088,7 +3094,7 @@ H5O_get_rc_and_type(const H5O_loc_t *loc, hid_t dxpl_id, unsigned *rc, H5O_type_
     HDassert(loc);
 
     /* Get the object header */
-    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC_READ)))
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to load object header")
 
     /* Set the object's reference count */
@@ -3461,7 +3467,7 @@ H5O_dec_rc_by_loc(const H5O_loc_t *loc, hid_t dxpl_id)
     HDassert(loc);
 
     /* Get header */
-    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC_READ)))
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__READ_ONLY_FLAG)))
        HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to protect object header")
 
     /* Decrement the reference count on the object header */
diff --git a/src/H5Oattribute.c b/src/H5Oattribute.c
index 46e7ce4..52f414b 100644
--- a/src/H5Oattribute.c
+++ b/src/H5Oattribute.c
@@ -483,7 +483,7 @@ H5O_attr_open_by_name(const H5O_loc_t *loc, const char *name, hid_t dxpl_id)
     HDassert(name);
 
     /* Protect the object header to iterate over */
-    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC_READ)))
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_ATTR, H5E_CANTPROTECT, NULL, "unable to load object header")
 
     /* Check for attribute info stored */
@@ -632,7 +632,7 @@ H5O_attr_open_by_idx(const H5O_loc_t *loc, H5_index_t idx_type,
         HGOTO_ERROR(H5E_ATTR, H5E_BADITER, NULL, "can't locate attribute")
 
     /* Protect the object header to iterate over */
-    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC_READ)))
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_ATTR, H5E_CANTPROTECT, NULL, "unable to load object header")
 
     /* Find out whether it has already been opened.  If it has, close the object
@@ -1283,7 +1283,7 @@ H5O_attr_iterate_real(hid_t loc_id, const H5O_loc_t *loc, hid_t dxpl_id,
     HDassert(attr_op);
 
     /* Protect the object header to iterate over */
-    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC_READ)))
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_ATTR, H5E_CANTPROTECT, FAIL, "unable to load object header")
 
     /* Check for attribute info stored */
@@ -1846,7 +1846,7 @@ H5O_attr_exists(const H5O_loc_t *loc, const char *name, hid_t dxpl_id)
     HDassert(name);
 
     /* Protect the object header to iterate over */
-    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC_READ)))
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_ATTR, H5E_CANTPROTECT, FAIL, "unable to load object header")
 
     /* Check for attribute info stored */
@@ -2000,7 +2000,7 @@ H5O_attr_count(const H5O_loc_t *loc, hid_t dxpl_id)
     HDassert(loc);
 
     /* Protect the object header to iterate over */
-    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC_READ)))
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_ATTR, H5E_CANTPROTECT, FAIL, "unable to load object header")
 
     /* Retrieve # of attributes on object */
diff --git a/src/H5Ocache.c b/src/H5Ocache.c
index 816e06a..203d0fc 100644
--- a/src/H5Ocache.c
+++ b/src/H5Ocache.c
@@ -68,17 +68,25 @@
 /********************/
 
 /* Metadata cache callbacks */
-static H5O_t *H5O_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata);
-static herr_t H5O_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5O_t *oh, unsigned H5_ATTR_UNUSED * flags_ptr);
-static herr_t H5O_dest(H5F_t *f, H5O_t *oh);
-static herr_t H5O_clear(H5F_t *f, H5O_t *oh, hbool_t destroy);
-static herr_t H5O_size(const H5F_t *f, const H5O_t *oh, size_t *size_ptr);
-
-static H5O_chunk_proxy_t *H5O_cache_chk_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata);
-static herr_t H5O_cache_chk_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5O_chunk_proxy_t *chk_proxy, unsigned H5_ATTR_UNUSED * flags_ptr);
-static herr_t H5O_cache_chk_dest(H5F_t *f, H5O_chunk_proxy_t *chk_proxy);
-static herr_t H5O_cache_chk_clear(H5F_t *f, H5O_chunk_proxy_t *chk_proxy, hbool_t destroy);
-static herr_t H5O_cache_chk_size(const H5F_t *f, const H5O_chunk_proxy_t *chk_proxy, size_t *size_ptr);
+static herr_t H5O__cache_get_load_size(const void *udata, size_t *image_len);
+static void *H5O__cache_deserialize(const void *image, size_t len,
+    void *udata, hbool_t *dirty); 
+static herr_t H5O__cache_image_len(const void *thing, size_t *image_len,
+    hbool_t *compressed_ptr, size_t *compressed_image_len_ptr);
+static herr_t H5O__cache_serialize(const H5F_t *f, void *image, size_t len,
+    void *thing); 
+static herr_t H5O__cache_free_icr(void *thing);
+static herr_t H5O__cache_clear(const H5F_t *f, void *thing, hbool_t about_to_destroy);
+
+static herr_t H5O__cache_chk_get_load_size(const void *udata, size_t *image_len);
+static void *H5O__cache_chk_deserialize(const void *image, size_t len,
+    void *udata, hbool_t *dirty); 
+static herr_t H5O__cache_chk_image_len(const void *thing, size_t *image_len,
+    hbool_t *compressed_ptr, size_t *compressed_image_len_ptr);
+static herr_t H5O__cache_chk_serialize(const H5F_t *f, void *image, size_t len,
+    void *thing);
+static herr_t H5O__cache_chk_free_icr(void *thing);
+static herr_t H5O__cache_chk_clear(const H5F_t *f, void *thing, hbool_t about_to_destroy);
 
 /* Chunk proxy routines */
 static herr_t H5O__chunk_proxy_dest(H5O_chunk_proxy_t *chunk_proxy);
@@ -99,24 +107,36 @@ static herr_t H5O__add_cont_msg(H5O_cont_msgs_t *cont_msg_info,
 
 /* H5O object header prefix inherits cache-like properties from H5AC */
 const H5AC_class_t H5AC_OHDR[1] = {{
-    H5AC_OHDR_ID,
-    (H5AC_load_func_t)H5O_load,
-    (H5AC_flush_func_t)H5O_flush,
-    (H5AC_dest_func_t)H5O_dest,
-    (H5AC_clear_func_t)H5O_clear,
-    (H5AC_notify_func_t)NULL,
-    (H5AC_size_func_t)H5O_size,
+    H5AC_OHDR_ID,                       /* Metadata client ID */
+    "object header",                    /* Metadata client name (for debugging) */
+    H5FD_MEM_OHDR,                      /* File space memory type for client */
+    H5AC__CLASS_SPECULATIVE_LOAD_FLAG,  /* Client class behavior flags */
+    H5O__cache_get_load_size,           /* 'get_load_size' callback */
+    H5O__cache_deserialize,             /* 'deserialize' callback */
+    H5O__cache_image_len,               /* 'image_len' callback */
+    NULL,                               /* 'pre_serialize' callback */
+    H5O__cache_serialize,               /* 'serialize' callback */
+    NULL,                               /* 'notify' callback */
+    H5O__cache_free_icr,                /* 'free_icr' callback */
+    H5O__cache_clear,                   /* 'clear' callback */
+    NULL,                               /* 'fsf_size' callback */
 }};
 
 /* H5O object header chunk inherits cache-like properties from H5AC */
 const H5AC_class_t H5AC_OHDR_CHK[1] = {{
-    H5AC_OHDR_CHK_ID,
-    (H5AC_load_func_t)H5O_cache_chk_load,
-    (H5AC_flush_func_t)H5O_cache_chk_flush,
-    (H5AC_dest_func_t)H5O_cache_chk_dest,
-    (H5AC_clear_func_t)H5O_cache_chk_clear,
-    (H5AC_notify_func_t)NULL,
-    (H5AC_size_func_t)H5O_cache_chk_size,
+    H5AC_OHDR_CHK_ID,                   /* Metadata client ID */
+    "object header continuation chunk", /* Metadata client name (for debugging) */
+    H5FD_MEM_OHDR,                      /* File space memory type for client */
+    H5AC__CLASS_NO_FLAGS_SET,           /* Client class behavior flags */
+    H5O__cache_chk_get_load_size,       /* 'get_load_size' callback */
+    H5O__cache_chk_deserialize,         /* 'deserialize' callback */
+    H5O__cache_chk_image_len,           /* 'image_len' callback */
+    NULL,                               /* 'pre_serialize' callback */
+    H5O__cache_chk_serialize,           /* 'serialize' callback */
+    NULL,                               /* 'notify' callback */
+    H5O__cache_chk_free_icr,            /* 'free_icr' callback */
+    H5O__cache_chk_clear,               /* 'clear' callback */
+    NULL,                               /* 'fsf_size' callback */
 }};
 
 /* Declare external the free list for H5O_unknown_t's */
@@ -141,55 +161,75 @@ H5FL_SEQ_DEFINE(H5O_cont_t);
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5O_load
+ * Function:    H5O__cache_get_load_size()
  *
- * Purpose:	Loads an object header from disk.
+ * Purpose:	Tell the metadata cache how much data to read from file in 
+ *		the first speculative read for the object header.  Note that we do 
+ *		not have to be concerned about reading past the end of file, as the 
+ *		cache will clamp the read to avoid this if needed.
  *
- * Return:	Success:	Pointer to the new object header.
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
  *
- *		Failure:	NULL
+ * Programmer:  John Mainzer
+ *              7/28/14
  *
- * Programmer:	Robb Matzke
- *		matzke@llnl.gov
- *		Aug  5 1997
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5O__cache_get_load_size(const void H5_ATTR_UNUSED *_udata, size_t *image_len)
+{
+    FUNC_ENTER_STATIC_NOERR
+
+    /* Check arguments */
+    HDassert(image_len);
+
+    *image_len = H5O_SPEC_READ_SIZE;
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5O__cache_get_load_size() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5O__cache_deserialize
+ *
+ * Purpose:	Attempt to deserialize the object header contained in the 
+ *		supplied buffer, load the data into an instance of H5O_t, and 
+ *		return a pointer to the new instance.
+ *
+ *		Note that the object header is read with with a speculative read.  
+ *		If the initial read is too small, make note of this fact and return 
+ *     		without error.  H5C_load_entry() will note the size discrepency
+ *		and retry the deserialize operation with the correct size read.
+ *
+ * Return:      Success:        Pointer to in core representation
+ *              Failure:        NULL
+ *
+ * Programmer:  John Mainzer
+ *              7/28/14
  *
  *-------------------------------------------------------------------------
  */
-static H5O_t *
-H5O_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
+static void *
+H5O__cache_deserialize(const void *_image, size_t len, void *_udata,
+    hbool_t *dirty)
 {
-    H5O_t	*oh = NULL;     /* Object header read in */
-    H5O_cache_ud_t *udata = (H5O_cache_ud_t *)_udata;       /* User data for callback */
-    H5WB_t      *wb = NULL;     /* Wrapped buffer for prefix data */
-    uint8_t     read_buf[H5O_SPEC_READ_SIZE];       /* Buffer for speculative read */
-    const uint8_t *p;           /* Pointer into buffer to decode */
-    uint8_t     *buf;           /* Buffer to decode */
-    size_t	spec_read_size; /* Size of buffer to speculatively read in */
-    size_t	prefix_size;    /* Size of object header prefix */
-    size_t	buf_size;       /* Size of prefix+chunk #0 buffer */
-    haddr_t     eoa;		/* Relative end of file address	*/
-    H5O_t	*ret_value;     /* Return value */
-
-    FUNC_ENTER_NOAPI_NOINIT
+    H5O_t          *oh = NULL;          /* Object header read in */
+    H5O_cache_ud_t *udata = (H5O_cache_ud_t *)_udata;   /* User data for callback */
+    const uint8_t  *image = (const uint8_t *)_image;    /* Pointer into buffer to decode */
+    size_t          prefix_size;        /* Size of object header prefix */
+    size_t          buf_size;           /* Size of prefix+chunk #0 buffer */
+    void *          ret_value = NULL;   /* Return value */
+
+    FUNC_ENTER_STATIC
 
     /* Check arguments */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
+    HDassert(image);
+    HDassert(len > 0); 
     HDassert(udata);
     HDassert(udata->common.f);
     HDassert(udata->common.cont_msg_info);
-
-    /* Make certain we don't speculatively read off the end of the file */
-    if(HADDR_UNDEF == (eoa = H5F_get_eoa(f, H5FD_MEM_OHDR)))
-        HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, NULL, "unable to determine file size")
-
-    /* Compute the size of the speculative object header buffer */
-    H5_CHECKED_ASSIGN(spec_read_size, size_t, MIN(eoa - addr, H5O_SPEC_READ_SIZE), hsize_t);
-
-    /* Attempt to speculatively read both object header prefix and first chunk */
-    if(H5F_block_read(f, H5FD_MEM_OHDR, addr, spec_read_size, dxpl_id, read_buf) < 0)
-	HGOTO_ERROR(H5E_OHDR, H5E_READERROR, NULL, "unable to read object header")
-    p = read_buf;
+    HDassert(dirty);
 
     /* Allocate space for the object header data structure */
     if(NULL == (oh = H5FL_CALLOC(H5O_t)))
@@ -201,18 +241,18 @@ H5O_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
 
     /* Check for presence of magic number */
     /* (indicates version 2 or later) */
-    if(!HDmemcmp(p, H5O_HDR_MAGIC, (size_t)H5_SIZEOF_MAGIC)) {
+    if(!HDmemcmp(image, H5O_HDR_MAGIC, (size_t)H5_SIZEOF_MAGIC)) {
         /* Magic number */
-        p += H5_SIZEOF_MAGIC;
+        image += H5_SIZEOF_MAGIC;
 
         /* Version */
-        oh->version = *p++;
-        if(H5O_VERSION_2 != oh->version)
+        oh->version = *image++;
+        if(H5O_VERSION_2 != oh->version) 
             HGOTO_ERROR(H5E_OHDR, H5E_VERSION, NULL, "bad object header version number")
 
         /* Flags */
-        oh->flags = *p++;
-        if(oh->flags & ~H5O_HDR_ALL_FLAGS)
+        oh->flags = *image++;
+        if(oh->flags & ~H5O_HDR_ALL_FLAGS) 
             HGOTO_ERROR(H5E_OHDR, H5E_BADVALUE, NULL, "unknown object header status flag(s)")
 
         /* Number of links to object (unless overridden by refcount message) */
@@ -222,13 +262,13 @@ H5O_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
         if(oh->flags & H5O_HDR_STORE_TIMES) {
             uint32_t tmp;       /* Temporary value */
 
-            UINT32DECODE(p, tmp);
+            UINT32DECODE(image, tmp);
             oh->atime = (time_t)tmp;
-            UINT32DECODE(p, tmp);
+            UINT32DECODE(image, tmp);
             oh->mtime = (time_t)tmp;
-            UINT32DECODE(p, tmp);
+            UINT32DECODE(image, tmp);
             oh->ctime = (time_t)tmp;
-            UINT32DECODE(p, tmp);
+            UINT32DECODE(image, tmp);
             oh->btime = (time_t)tmp;
         } /* end if */
         else
@@ -236,8 +276,9 @@ H5O_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
 
         /* Attribute fields */
         if(oh->flags & H5O_HDR_ATTR_STORE_PHASE_CHANGE) {
-            UINT16DECODE(p, oh->max_compact);
-            UINT16DECODE(p, oh->min_dense);
+            UINT16DECODE(image, oh->max_compact);
+            UINT16DECODE(image, oh->min_dense);
+
             if(oh->max_compact < oh->min_dense)
                 HGOTO_ERROR(H5E_OHDR, H5E_BADVALUE, NULL, "bad object header attribute phase change values")
         } /* end if */
@@ -249,19 +290,19 @@ H5O_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
         /* First chunk size */
         switch(oh->flags & H5O_HDR_CHUNK0_SIZE) {
             case 0:     /* 1 byte size */
-                oh->chunk0_size = *p++;
+                oh->chunk0_size = *image++;
                 break;
 
             case 1:     /* 2 byte size */
-                UINT16DECODE(p, oh->chunk0_size);
+                UINT16DECODE(image, oh->chunk0_size);
                 break;
 
             case 2:     /* 4 byte size */
-                UINT32DECODE(p, oh->chunk0_size);
+                UINT32DECODE(image, oh->chunk0_size);
                 break;
 
             case 3:     /* 8 byte size */
-                UINT64DECODE(p, oh->chunk0_size);
+                UINT64DECODE(image, oh->chunk0_size);
                 break;
 
             default:
@@ -272,7 +313,7 @@ H5O_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
     } /* end if */
     else {
         /* Version */
-        oh->version = *p++;
+        oh->version = *image++;
         if(H5O_VERSION_1 != oh->version)
             HGOTO_ERROR(H5E_OHDR, H5E_VERSION, NULL, "bad object header version number")
 
@@ -280,13 +321,13 @@ H5O_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
         oh->flags = H5O_CRT_OHDR_FLAGS_DEF;
 
         /* Reserved */
-        p++;
+        image++;
 
         /* Number of messages */
-        UINT16DECODE(p, udata->v1_pfx_nmesgs);
+        UINT16DECODE(image, udata->v1_pfx_nmesgs);
 
         /* Link count */
-        UINT32DECODE(p, oh->nlink);
+        UINT32DECODE(image, oh->nlink);
 
         /* Reset unused time fields */
         oh->atime = oh->mtime = oh->ctime = oh->btime = 0;
@@ -296,45 +337,36 @@ H5O_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
         oh->min_dense = 0;
 
         /* First chunk size */
-        UINT32DECODE(p, oh->chunk0_size);
-        if((udata->v1_pfx_nmesgs > 0 && oh->chunk0_size < H5O_SIZEOF_MSGHDR_OH(oh)) ||
-                (udata->v1_pfx_nmesgs == 0 && oh->chunk0_size > 0))
+        UINT32DECODE(image, oh->chunk0_size);
+
+        if((udata->v1_pfx_nmesgs > 0 && 
+                oh->chunk0_size < H5O_SIZEOF_MSGHDR_OH(oh)) ||
+                    (udata->v1_pfx_nmesgs == 0 && oh->chunk0_size > 0))
             HGOTO_ERROR(H5E_OHDR, H5E_BADVALUE, NULL, "bad object header chunk size")
 
         /* Reserved, in version 1 (for 8-byte alignment padding) */
-        p += 4;
+        image += 4;
     } /* end else */
 
     /* Determine object header prefix length */
-    prefix_size = (size_t)(p - (const uint8_t *)read_buf);
+    prefix_size = (size_t)(image - (const uint8_t *)_image);
     HDassert((size_t)prefix_size == (size_t)(H5O_SIZEOF_HDR(oh) - H5O_SIZEOF_CHKSUM_OH(oh)));
 
     /* Compute the size of the buffer used */
     buf_size = oh->chunk0_size + (size_t)H5O_SIZEOF_HDR(oh);
 
-    /* Check if the speculative read was large enough to parse the first chunk */
-    if(spec_read_size < buf_size) {
-        /* Wrap the local buffer for serialized header info */
-        if(NULL == (wb = H5WB_wrap(read_buf, sizeof(read_buf))))
-            HGOTO_ERROR(H5E_OHDR, H5E_CANTINIT, NULL, "can't wrap buffer")
-
-        /* Get a pointer to a buffer that's large enough for serialized header */
-        if(NULL == (buf = (uint8_t *)H5WB_actual(wb, buf_size)))
-            HGOTO_ERROR(H5E_OHDR, H5E_NOSPACE, NULL, "can't get actual buffer")
-
-        /* Copy existing raw data into new buffer */
-        HDmemcpy(buf, read_buf, spec_read_size);
-
-        /* Read rest of the raw data */
-        if(H5F_block_read(f, H5FD_MEM_OHDR, (addr + spec_read_size), (buf_size - spec_read_size), dxpl_id, (buf + spec_read_size)) < 0)
-            HGOTO_ERROR(H5E_OHDR, H5E_READERROR, NULL, "unable to read object header data")
+    /* Check to see if the buffer provided is large enough to contain both 
+     * the prefix and the first chunk.  If it isn't, make note of the desired
+     * size, but otherwise do nothing.  H5C_load_entry() will notice the 
+     * discrepency, load the correct size buffer, and retry the deserialize.
+     */
+    if(len >= buf_size) {
+        /* Parse the first chunk */
+        if(H5O__chunk_deserialize(oh, udata->common.addr, oh->chunk0_size, (const uint8_t *)_image, &(udata->common), dirty) < 0)
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTINIT, NULL, "can't deserialize first object header chunk")
     } /* end if */
     else
-        buf = read_buf;
-
-    /* Parse the first chunk */
-    if(H5O__chunk_deserialize(oh, udata->common.addr, oh->chunk0_size, buf, &(udata->common), &oh->cache_info.is_dirty) < 0)
-        HGOTO_ERROR(H5E_OHDR, H5E_CANTINIT, NULL, "can't deserialize first object header chunk")
+        HDassert(!udata->made_attempt);
 
     /* Note that we've loaded the object header from the file */
     udata->made_attempt = TRUE;
@@ -343,202 +375,234 @@ H5O_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
     ret_value = oh;
 
 done:
-    /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-        HDONE_ERROR(H5E_OHDR, H5E_CLOSEERROR, NULL, "can't close wrapped buffer")
-
     /* Release the [possibly partially initialized] object header on errors */
     if(!ret_value && oh)
         if(H5O_free(oh) < 0)
             HDONE_ERROR(H5E_OHDR, H5E_CANTRELEASE, NULL, "unable to destroy object header data")
 
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5O_load() */
+} /* end H5O__cache_deserialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5O_flush
+ * Function:    H5O__cache_image_len
  *
- * Purpose:	Flushes (and destroys) an object header.
+ * Purpose:	Compute the size in bytes of the specified instance of
+ *		H5O_t on disk, and return it in *image_len.  On failure,
+ *		the value of *image_len is undefined.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
  *
- * Programmer:	Robb Matzke
- *		matzke@llnl.gov
- *		Aug  5 1997
+ * Programmer:  John Mainzer
+ *              7/28/14
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5O_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t H5_ATTR_UNUSED addr, H5O_t *oh, unsigned H5_ATTR_UNUSED * flags_ptr)
+H5O__cache_image_len(const void *_thing, size_t *image_len,
+    hbool_t H5_ATTR_UNUSED *compressed_ptr, size_t H5_ATTR_UNUSED *compressed_image_len_ptr)
 {
-    herr_t ret_value = SUCCEED; /* Return value */
+    const H5O_t *oh = (const H5O_t *)_thing;    /* Object header to query */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC_NOERR
 
     /* Check arguments */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
     HDassert(oh);
+    HDassert(oh->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(oh->cache_info.type == H5AC_OHDR);
+    HDassert(image_len);
+
+    /* Report the object header's prefix+first chunk length */
+    if(oh->chunk0_size)
+       *image_len = (size_t)H5O_SIZEOF_HDR(oh) + oh->chunk0_size;
+    else
+       *image_len = oh->chunk[0].size;
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5O__cache_image_len() */
 
-    /* flush */
-    if(oh->cache_info.is_dirty) {
-        uint8_t	*p;             /* Pointer to object header prefix buffer */
+/********************************/
+/* no H5O_cache_pre_serialize() */
+/********************************/
 
+
+/*-------------------------------------------------------------------------
+ * Function:    H5O__cache_serialize
+ *
+ * Purpose:	Serialize the contents of the supplied object header, and
+ *		load this data into the supplied buffer.
+ *
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
+ *
+ * Programmer:  John Mainzer
+ *              7/28/14
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5O__cache_serialize(const H5F_t *f, void *image, size_t len, void *_thing)
+{
+    H5O_t      *oh = (H5O_t *)_thing;   /* Object header to encode */
+    uint8_t     *chunk_image;           /* Pointer to object header prefix buffer */
+    herr_t      ret_value = SUCCEED;    /* Return value */
+
+    FUNC_ENTER_STATIC
+
+    /* Check arguments */
+    HDassert(f);
+    HDassert(image);
+    HDassert(oh);
+    HDassert(oh->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(oh->cache_info.type == H5AC_OHDR);
+    HDassert(oh->chunk[0].size == len);
 #ifdef H5O_DEBUG
-H5O_assert(oh);
+    H5O_assert(oh);
 #endif /* H5O_DEBUG */
 
-        /* Point to raw data 'image' for first chunk, which has room for the prefix */
-        p = oh->chunk[0].image;
-
-        /* Later versions of object header prefix have different format and
-         * also require that chunk 0 always be updated, since the checksum
-         * on the entire block of memory needs to be updated if anything is
-         * modified */
-        if(oh->version > H5O_VERSION_1) {
-            uint64_t chunk0_size;       /* Size of chunk 0's data */
+    /* Point to raw data 'image' for first chunk, which 
+     * has room for the prefix 
+     */
+    chunk_image = oh->chunk[0].image;
 
-            HDassert(oh->chunk[0].size >= (size_t)H5O_SIZEOF_HDR(oh));
-            chunk0_size = oh->chunk[0].size - (size_t)H5O_SIZEOF_HDR(oh);
+    /* Later versions of object header prefix have different format and
+     * also require that chunk 0 always be updated, since the checksum
+     * on the entire block of memory needs to be updated if anything is
+     * modified 
+     */
+    if(oh->version > H5O_VERSION_1) {
+        uint64_t chunk0_size;       /* Size of chunk 0's data */
 
-            /* Verify magic number */
-            HDassert(!HDmemcmp(p, H5O_HDR_MAGIC, H5_SIZEOF_MAGIC));
-            p += H5_SIZEOF_MAGIC;
+        HDassert(oh->chunk[0].size >= (size_t)H5O_SIZEOF_HDR(oh));
+        chunk0_size = oh->chunk[0].size - (size_t)H5O_SIZEOF_HDR(oh);
 
-            /* Version */
-            *p++ = oh->version;
+        /* Verify magic number */
+        HDassert(!HDmemcmp(chunk_image, H5O_HDR_MAGIC, H5_SIZEOF_MAGIC));
+        chunk_image += H5_SIZEOF_MAGIC;
 
-            /* Flags */
-            *p++ = oh->flags;
+        /* Version */
+        *chunk_image++ = oh->version;
 
-            /* Time fields */
-            if(oh->flags & H5O_HDR_STORE_TIMES) {
-                UINT32ENCODE(p, oh->atime);
-                UINT32ENCODE(p, oh->mtime);
-                UINT32ENCODE(p, oh->ctime);
-                UINT32ENCODE(p, oh->btime);
-            } /* end if */
+        /* Flags */
+        *chunk_image++ = oh->flags;
 
-            /* Attribute fields */
-            if(oh->flags & H5O_HDR_ATTR_STORE_PHASE_CHANGE) {
-                UINT16ENCODE(p, oh->max_compact);
-                UINT16ENCODE(p, oh->min_dense);
-            } /* end if */
+        /* Time fields */
+        if(oh->flags & H5O_HDR_STORE_TIMES) {
+            UINT32ENCODE(chunk_image, oh->atime);
+            UINT32ENCODE(chunk_image, oh->mtime);
+            UINT32ENCODE(chunk_image, oh->ctime);
+            UINT32ENCODE(chunk_image, oh->btime);
+        } /* end if */
 
-            /* First chunk size */
-            switch(oh->flags & H5O_HDR_CHUNK0_SIZE) {
-                case 0:     /* 1 byte size */
-                    HDassert(chunk0_size < 256);
-                    *p++ = (uint8_t)chunk0_size;
-                    break;
-
-                case 1:     /* 2 byte size */
-                    HDassert(chunk0_size < 65536);
-                    UINT16ENCODE(p, chunk0_size);
-                    break;
-
-                case 2:     /* 4 byte size */
-		    /* use <= 2**32 -1 to stay within 4 bytes integer range */
-                    HDassert(chunk0_size <= 4294967295UL);
-                    UINT32ENCODE(p, chunk0_size);
-                    break;
-
-                case 3:     /* 8 byte size */
-                    UINT64ENCODE(p, chunk0_size);
-                    break;
-
-                default:
-                    HGOTO_ERROR(H5E_OHDR, H5E_BADVALUE, FAIL, "bad size for chunk 0")
-            } /* end switch */
+        /* Attribute fields */
+        if(oh->flags & H5O_HDR_ATTR_STORE_PHASE_CHANGE) {
+            UINT16ENCODE(chunk_image, oh->max_compact);
+            UINT16ENCODE(chunk_image, oh->min_dense);
         } /* end if */
-        else {
-            /* Version */
-            *p++ = oh->version;
 
-            /* Reserved */
-            *p++ = 0;
+        /* First chunk size */
+        switch(oh->flags & H5O_HDR_CHUNK0_SIZE) {
+            case 0:     /* 1 byte size */
+                HDassert(chunk0_size < 256);
+                *chunk_image++ = (uint8_t)chunk0_size;
+                break;
+
+            case 1:     /* 2 byte size */
+                HDassert(chunk0_size < 65536);
+                UINT16ENCODE(chunk_image, chunk0_size);
+                break;
+
+            case 2:     /* 4 byte size */
+                /* use <= 2**32 -1 to stay within 4 bytes integer range */
+                HDassert(chunk0_size <= 4294967295UL);
+                UINT32ENCODE(chunk_image, chunk0_size);
+                break;
 
-            /* Number of messages */
+            case 3:     /* 8 byte size */
+                UINT64ENCODE(chunk_image, chunk0_size);
+                break;
+
+            default:
+                HGOTO_ERROR(H5E_OHDR, H5E_BADVALUE, FAIL, "bad size for chunk 0")
+        } /* end switch */
+    } /* end if */
+    else {
+        /* Version */
+        *chunk_image++ = oh->version;
+
+        /* Reserved */
+        *chunk_image++ = 0;
+
+        /* Number of messages */
 #ifdef H5O_ENABLE_BAD_MESG_COUNT
-            if(oh->store_bad_mesg_count)
-                UINT16ENCODE(p, (oh->nmesgs - 1))
-            else
+        if(oh->store_bad_mesg_count)
+           UINT16ENCODE(chunk_image, (oh->nmesgs - 1))
+        else
 #endif /* H5O_ENABLE_BAD_MESG_COUNT */
-                UINT16ENCODE(p, oh->nmesgs);
-
-            /* Link count */
-            UINT32ENCODE(p, oh->nlink);
+            UINT16ENCODE(chunk_image, oh->nmesgs);
 
-            /* First chunk size */
-            UINT32ENCODE(p, (oh->chunk[0].size - (size_t)H5O_SIZEOF_HDR(oh)));
+        /* Link count */
+        UINT32ENCODE(chunk_image, oh->nlink);
 
-            /* Zero to alignment */
-            HDmemset(p, 0, (size_t)(H5O_SIZEOF_HDR(oh) - 12));
-            p += (size_t)(H5O_SIZEOF_HDR(oh) - 12);
-        } /* end else */
-        HDassert((size_t)(p - oh->chunk[0].image) == (size_t)(H5O_SIZEOF_HDR(oh) - H5O_SIZEOF_CHKSUM_OH(oh)));
+        /* First chunk size */
+        UINT32ENCODE(chunk_image, (oh->chunk[0].size - (size_t)H5O_SIZEOF_HDR(oh)));
 
-        /* Serialize messages for this chunk */
-        if(H5O__chunk_serialize(f, oh, (unsigned)0) < 0)
-            HGOTO_ERROR(H5E_OHDR, H5E_CANTSERIALIZE, FAIL, "unable to serialize first object header chunk")
+        /* Zero to alignment */
+        HDmemset(chunk_image, 0, (size_t)(H5O_SIZEOF_HDR(oh) - 12));
+        chunk_image += (size_t)(H5O_SIZEOF_HDR(oh) - 12);
+    } /* end else */
 
-        /* Write the chunk out */
-        HDassert(H5F_addr_defined(oh->chunk[0].addr));
-        if(H5F_block_write(f, H5FD_MEM_OHDR, oh->chunk[0].addr, oh->chunk[0].size, dxpl_id, oh->chunk[0].image) < 0)
-            HGOTO_ERROR(H5E_OHDR, H5E_WRITEERROR, FAIL, "unable to write object header chunk to disk")
+    HDassert((size_t)(chunk_image - oh->chunk[0].image) == (size_t)(H5O_SIZEOF_HDR(oh) - H5O_SIZEOF_CHKSUM_OH(oh)));
 
-        /* Mark object header as clean now */
-	oh->cache_info.is_dirty = FALSE;
-    } /* end if */
+    /* Serialize messages for this chunk */
+    if(H5O__chunk_serialize(f, oh, (unsigned)0) < 0) 
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTSERIALIZE, FAIL, "unable to serialize first object header chunk")
 
-    /* Destroy the object header, if requested */
-    if(destroy)
-        if(H5O_dest(f, oh) < 0)
-	    HGOTO_ERROR(H5E_OHDR, H5E_CANTFREE, FAIL, "unable to destroy object header data")
+    /* copy the chunk into the image -- this is potentially expensive.  
+     * Can we rework things so that the object header and the cache 
+     * share a buffer?
+     */
+    HDmemcpy(image, oh->chunk[0].image, len);
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5O_flush() */
+} /* end H5O__cache_serialize() */
+
+/**********************************/
+/* no H5O_cache_notify() function */
+/**********************************/
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5O_dest
+ * Function:    H5O__cache_free_icr
  *
- * Purpose:	Destroys an object header.
+ * Purpose:	Free the in core representation of the supplied object header.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Note:	The metadata cache sets the object's cache_info.magic to
+ *		H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC before calling a free_icr
+ *		callback (checked in assert).
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Jan 15 2003
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
+ *
+ * Programmer:  John Mainzer
+ *              7/28/14
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5O_dest(H5F_t *f, H5O_t *oh)
-{
-    herr_t ret_value = SUCCEED;         /* Return value */
+H5O__cache_free_icr(void *_thing)
+{ 
+    H5O_t      *oh = (H5O_t *)_thing;   /* Object header to destroy */
+    herr_t      ret_value = SUCCEED;    /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
     /* Check arguments */
     HDassert(oh);
-    HDassert(oh->rc == 0);
-
-    /* Verify that node is clean */
-    HDassert(!oh->cache_info.is_dirty);
-
-    /* If we're going to free the space on disk, the address must be valid */
-    HDassert(!oh->cache_info.free_file_space_on_destroy || H5F_addr_defined(oh->cache_info.addr));
-
-    /* Check for releasing file space for object header */
-    if(oh->chunk && oh->cache_info.free_file_space_on_destroy) {
-        /* Free main (first) object header "chunk" */
-        /* (XXX: Nasty usage of internal DXPL value! -QAK) */
-        if(H5MF_xfree(f, H5FD_MEM_OHDR, H5AC_dxpl_id, oh->chunk[0].addr, (hsize_t)oh->chunk[0].size) < 0)
-            HGOTO_ERROR(H5E_OHDR, H5E_CANTFREE, FAIL, "unable to free object header")
-    } /* end if */
+    HDassert(oh->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC);
+    HDassert(oh->cache_info.type == H5AC_OHDR);
 
     /* Destroy object header */
     if(H5O_free(oh) < 0)
@@ -546,170 +610,143 @@ H5O_dest(H5F_t *f, H5O_t *oh)
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5O_dest() */
+} /* end H5O__cache_free_icr() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5O_clear
+ * Function:    H5O__cache_clear
  *
- * Purpose:	Mark a object header in memory as non-dirty.
+ * Purpose: 	Clear all dirty bits associated with this cache entry.
  *
- * Return:	Non-negative on success/Negative on failure
+ *		This is ncessary as the object header cache client maintains 
+ *		its own dirty bits on individual messages.  These dirty bits 
+ *		used to be cleared by the old V2 metadata cache flush callback,
+ *		but now the metadata cache must clear them explicitly, as 
+ *		the serialize callback does not imply that the data has been
+ *		written to disk.
  *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Mar 20 2003
- *
- * Changes:     In the parallel case, there is the possibility that the
- *              the object header may be flushed by different processes
- *              over the life of the computation.  Thus we must ensure
- *              that the chunk images are up to date before we mark the
- *              messages clean -- as otherwise we may overwrite valid
- *              data with a blank section of a chunk image.
+ *		This callback is also necessary for the parallel case.
  *
- *              To deal with this, I have added code to call
- *              H5O_chunk_serialize() for all chunks before we
- *              mark all messages as clean if we are not destroying the
- *              object.  Do this in the parallel case only, as the problem
- *              can only occur in this context.
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
  *
- *                                              JRM -- 10/12/10
+ * Programmer:  John Mainzer
+ *              9/22/14
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5O_clear(H5F_t *f, H5O_t *oh, hbool_t destroy)
-{
-    unsigned	u;      /* Local index variable */
-    herr_t ret_value = SUCCEED;
+H5O__cache_clear(const H5F_t *f, void *_thing, hbool_t about_to_destroy)
+{ 
+    H5O_t      *oh = (H5O_t *)_thing;   /* Object header to reset */
+    unsigned    u;                      /* Local index variable */
+    herr_t      ret_value = SUCCEED;    /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
     /* Check arguments */
     HDassert(oh);
+    HDassert(oh->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(oh->cache_info.type == H5AC_OHDR);
 
 #ifdef H5_HAVE_PARALLEL
-    if ( ( oh->cache_info.is_dirty ) && ( ! destroy ) ) {
-
-        size_t i;
-
-        /* scan through all chunks associated with the object header,
-         * and cause them to update their images for all entries currently
-         * marked dirty.  Must do this in the parallel case, as it is possible
-         * that this processor may clear this object header several times
-         * before flushing it -- thus causing undefined sections of the image
-         * to be written to disk overwriting valid data.
+    if((oh->nchunks > 0) && (!about_to_destroy)) {
+        /* Scan through chunk 0 (the chunk stored contiguously with this 
+         * object header) and cause it to update its image of all entries 
+         * currently marked dirty.  Must do this in the parallel case, as 
+         * it is possible that this processor may clear this object header 
+         * several times before flushing it -- thus causing undefined 
+         * sections of the image to be written to disk overwriting valid data.
          */
-
-        for ( i = 0; i < oh->nchunks; i++ ) {
-
-            if(H5O__chunk_serialize(f, oh, i) < 0)
-                HGOTO_ERROR(H5E_OHDR, H5E_CANTSERIALIZE, FAIL, "unable to serialize object header chunk")
-        }
-    }
+        if(H5O__chunk_serialize(f, oh, 0) < 0)
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTSERIALIZE, FAIL, "unable to serialize object header chunk")
+    } /* end if */
 #endif /* H5_HAVE_PARALLEL */
 
     /* Mark messages stored with the object header (i.e. messages in chunk 0) as clean */
     for(u = 0; u < oh->nmesgs; u++)
-        oh->mesg[u].dirty = FALSE;
+        if(oh->mesg[u].chunkno == 0)
+            oh->mesg[u].dirty = FALSE;
 
 #ifndef NDEBUG
     /* Reset the number of messages dirtied by decoding */
     oh->ndecode_dirtied = 0;
 #endif /* NDEBUG */
 
-    /* Mark whole header as clean */
-    oh->cache_info.is_dirty = FALSE;
-
-    if(destroy)
-        if(H5O_dest(f, oh) < 0)
-            HGOTO_ERROR(H5E_OHDR, H5E_CANTFREE, FAIL, "unable to destroy object header data")
-
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5O_clear() */
+} /* end H5O__cache_clear() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5O_size
+ * Function:    H5O__cache_chk_get_load_size()
  *
- * Purpose:	Compute the size in bytes of the specified instance of
- *              H5O_t on disk, and return it in *len_ptr.  On failure,
- *              the value of *len_ptr is undefined.
+ * Purpose:	Tell the metadata cache how large the on disk image of the 
+ *		chunk proxy is, so it can load the image into a buffer for the 
+ *		deserialize call.  In this case, we simply look up the size in 
+ *		the user data, and return it in *image_len,
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
  *
- * Programmer:	John Mainzer
- *		5/13/04
+ * Programmer:  John Mainzer
+ *              7/28/14
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5O_size(const H5F_t H5_ATTR_UNUSED *f, const H5O_t *oh, size_t *size_ptr)
+H5O__cache_chk_get_load_size(const void *_udata, size_t *image_len)
 {
-    FUNC_ENTER_NOAPI_NOINIT_NOERR
+    const H5O_chk_cache_ud_t *udata = (const H5O_chk_cache_ud_t *)_udata;       /* User data for callback */
 
-    /* check args */
-    HDassert(oh);
-    HDassert(size_ptr);
+    FUNC_ENTER_STATIC_NOERR
 
-    /* Report the object header's prefix+first chunk length */
-    if(oh->chunk0_size)
-       *size_ptr = (size_t)H5O_SIZEOF_HDR(oh) + oh->chunk0_size;
-    else
-       *size_ptr = oh->chunk[0].size;
+    /* Check arguments */
+    HDassert(udata);
+    HDassert(udata->oh);
+    HDassert(image_len);
+
+    *image_len = udata->size;
 
     FUNC_LEAVE_NOAPI(SUCCEED)
-} /* H5O_size() */
+} /* end H5O__cache_chk_get_load_size() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5O_cache_chk_load
+ * Function:    H5O__cache_chk_deserialize
  *
- * Purpose:	Loads an object header continuation chunk from disk.
+ * Purpose:	Attempt to deserialize the object header continuation chunk
+ *		contained in the supplied buffer, load the data into an instance 
+ *		of H5O_chunk_proxy_t, and return a pointer to the new instance.
  *
- * Return:	Success:	Pointer to the new object header chunk proxy.
- *		Failure:	NULL
+ * Return:      Success:        Pointer to in core representation
+ *              Failure:        NULL
  *
- * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Jul 12 2008
+ * Programmer:  John Mainzer
+ *              7/28/14
  *
  *-------------------------------------------------------------------------
  */
-static H5O_chunk_proxy_t *
-H5O_cache_chk_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
+static void *
+H5O__cache_chk_deserialize(const void *image, size_t len, void *_udata,
+    hbool_t *dirty)
 {
-    H5O_chunk_proxy_t	*chk_proxy = NULL;     /* Chunk proxy object */
-    H5O_chk_cache_ud_t *udata = (H5O_chk_cache_ud_t *)_udata;       /* User data for callback */
-    H5WB_t      *wb = NULL;             /* Wrapped buffer for prefix data */
-    uint8_t     chunk_buf[H5O_SPEC_READ_SIZE];       /* Buffer for speculative read */
-    uint8_t     *buf;                   /* Buffer to decode */
-    H5O_chunk_proxy_t	*ret_value;     /* Return value */
+    H5O_chunk_proxy_t  *chk_proxy = NULL;     /* Chunk proxy object */
+    H5O_chk_cache_ud_t *udata = (H5O_chk_cache_ud_t *)_udata;   /* User data for callback */
+    void *              ret_value;      /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
     /* Check arguments */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
+    HDassert(image);
+    HDassert(len > 0);
     HDassert(udata);
     HDassert(udata->oh);
+    HDassert(dirty);
 
     /* Allocate space for the object header data structure */
-    if(NULL == (chk_proxy = H5FL_CALLOC(H5O_chunk_proxy_t)))
-	HGOTO_ERROR(H5E_OHDR, H5E_CANTALLOC, NULL, "memory allocation failed")
-
-    /* Wrap the local buffer for serialized header info */
-    if(NULL == (wb = H5WB_wrap(chunk_buf, sizeof(chunk_buf))))
-        HGOTO_ERROR(H5E_OHDR, H5E_CANTINIT, NULL, "can't wrap buffer")
-
-    /* Get a pointer to a buffer that's large enough for serialized header */
-    if(NULL == (buf = (uint8_t *)H5WB_actual(wb, udata->size)))
-        HGOTO_ERROR(H5E_OHDR, H5E_NOSPACE, NULL, "can't get actual buffer")
-
-    /* Read rest of the raw data */
-    if(H5F_block_read(f, H5FD_MEM_OHDR, addr, udata->size, dxpl_id, buf) < 0)
-        HGOTO_ERROR(H5E_OHDR, H5E_READERROR, NULL, "unable to read object header continuation chunk")
+    if(NULL == (chk_proxy = H5FL_CALLOC(H5O_chunk_proxy_t))) 
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTALLOC, NULL, "memory allocation failed")
 
     /* Check if we are still decoding the object header */
     /* (as opposed to bringing a piece of it back from the file) */
@@ -719,7 +756,7 @@ H5O_cache_chk_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
         HDassert(udata->common.cont_msg_info);
 
         /* Parse the chunk */
-        if(H5O__chunk_deserialize(udata->oh, udata->common.addr, udata->size, buf, &(udata->common), &chk_proxy->cache_info.is_dirty) < 0)
+        if(H5O__chunk_deserialize(udata->oh, udata->common.addr, udata->size, (const uint8_t *)image, &(udata->common), dirty) < 0)
             HGOTO_ERROR(H5E_OHDR, H5E_CANTINIT, NULL, "can't deserialize object header chunk")
 
         /* Set the fields for the chunk proxy */
@@ -737,7 +774,7 @@ H5O_cache_chk_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
         /* Sanity check that the chunk representation we have in memory is 
          * the same as the one being brought in from disk.
          */
-        HDassert(0 == HDmemcmp(buf, chk_proxy->oh->chunk[chk_proxy->chunkno].image, chk_proxy->oh->chunk[chk_proxy->chunkno].size));
+        HDassert(0 == HDmemcmp(image, chk_proxy->oh->chunk[chk_proxy->chunkno].image, chk_proxy->oh->chunk[chk_proxy->chunkno].size));
     } /* end else */
 
     /* Increment reference count of object header */
@@ -748,213 +785,195 @@ H5O_cache_chk_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
     ret_value = chk_proxy;
 
 done:
-    /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-        HDONE_ERROR(H5E_OHDR, H5E_CLOSEERROR, NULL, "can't close wrapped buffer")
-
-    /* Release the [possibly partially initialized] object header on errors */
-    if(!ret_value && chk_proxy)
-        if(H5O__chunk_proxy_dest(chk_proxy) < 0)
-	    HDONE_ERROR(H5E_OHDR, H5E_CANTRELEASE, NULL, "unable to destroy object header chunk proxy")
-
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5O_cache_chk_load() */
+} /* end H5O__cache_chk_deserialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5O_cache_chk_flush
+ * Function:    H5O__cache_chk_image_len
  *
- * Purpose:	Flushes (and destroys) an object header continuation chunk.
+ * Purpose:	Return the on disk image size of a object header chunk to the 
+ *		metadata cache via the image_len.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
  *
- * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Jul 12 2008
+ * Programmer:  John Mainzer
+ *              7/28/14
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5O_cache_chk_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr,
-    H5O_chunk_proxy_t *chk_proxy, unsigned H5_ATTR_UNUSED * flags_ptr)
+H5O__cache_chk_image_len(const void *_thing, size_t *image_len,
+    hbool_t H5_ATTR_UNUSED *compressed_ptr, size_t H5_ATTR_UNUSED *compressed_image_len_ptr)
 {
-    herr_t ret_value = SUCCEED; /* Return value */
-
-    FUNC_ENTER_NOAPI_NOINIT
+    const H5O_chunk_proxy_t * chk_proxy = (const H5O_chunk_proxy_t *)_thing;    /* Chunk proxy to query */
 
-    /* flush */
-    if(chk_proxy->cache_info.is_dirty) {
-        /* Serialize messages for this chunk */
-        if(H5O__chunk_serialize(f, chk_proxy->oh, chk_proxy->chunkno) < 0)
-            HGOTO_ERROR(H5E_OHDR, H5E_CANTSERIALIZE, FAIL, "unable to serialize object header continuation chunk")
+    FUNC_ENTER_STATIC_NOERR
 
-        /* Write the chunk out */
-        HDassert(H5F_addr_defined(chk_proxy->oh->chunk[chk_proxy->chunkno].addr));
-        HDassert(H5F_addr_eq(addr, chk_proxy->oh->chunk[chk_proxy->chunkno].addr));
-        if(H5F_block_write(f, H5FD_MEM_OHDR, addr, chk_proxy->oh->chunk[chk_proxy->chunkno].size, dxpl_id, chk_proxy->oh->chunk[chk_proxy->chunkno].image) < 0)
-            HGOTO_ERROR(H5E_OHDR, H5E_WRITEERROR, FAIL, "unable to write object header continuation chunk to disk")
+    /* Check arguments */
+    HDassert(chk_proxy);
+    HDassert(chk_proxy->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(chk_proxy->cache_info.type == H5AC_OHDR_CHK);
+    HDassert(chk_proxy->oh);
+    HDassert(image_len);
 
-        /* Mark object header as clean now */
-	chk_proxy->cache_info.is_dirty = FALSE;
-    } /* end if */
+    *image_len = chk_proxy->oh->chunk[chk_proxy->chunkno].size;
 
-    /* Destroy the object header, if requested */
-    if(destroy)
-        if(H5O_cache_chk_dest(f, chk_proxy) < 0)
-	    HGOTO_ERROR(H5E_OHDR, H5E_CANTFREE, FAIL, "unable to destroy object header continuation chunk data")
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5O__cache_chk_image_len() */
 
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5O_cache_chk_flush() */
+/************************************/
+/* no H5O_cache_chk_pre_serialize() */
+/************************************/
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5O_cache_chk_dest
+ * Function:    H5O__cache_chk_serialize
  *
- * Purpose:	Destroys an object header continuation chunk.
+ * Purpose:	Given a pointer to an instance of an object header chunk and an 
+ *		appropriately sized buffer, serialize the contents of the 
+ *		instance for writing to disk, and copy the serialized data 
+ *		into the buffer.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
  *
- * Programmer:	Quincey Koziol
- *              koziol@hdfgroup.org
- *              July 12, 2008
+ * Programmer:  John Mainzer
+ *              7/28/14
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5O_cache_chk_dest(H5F_t *f, H5O_chunk_proxy_t *chk_proxy)
+H5O__cache_chk_serialize(const H5F_t *f, void *image, size_t len, void *_thing)
 {
-    herr_t      ret_value = SUCCEED;    /* Return value */
+    H5O_chunk_proxy_t * chk_proxy = (H5O_chunk_proxy_t *)_thing;        /* Object header chunk to serialize */
+    herr_t              ret_value = SUCCEED;    /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
     /* Check arguments */
+    HDassert(f);
+    HDassert(image);
     HDassert(chk_proxy);
-    HDassert(chk_proxy->chunkno > 0);
-
-    /* Verify that node is clean */
-    HDassert(chk_proxy->cache_info.is_dirty == FALSE);
+    HDassert(chk_proxy->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(chk_proxy->cache_info.type == H5AC_OHDR_CHK);
+    HDassert(chk_proxy->oh);
+    HDassert(chk_proxy->oh->chunk[chk_proxy->chunkno].size == len);
 
-    /* If we're going to free the space on disk, the address must be valid */
-    HDassert(!chk_proxy->cache_info.free_file_space_on_destroy || H5F_addr_defined(chk_proxy->cache_info.addr));
-
-    /* Check for releasing file space for object header */
-    if(chk_proxy->cache_info.free_file_space_on_destroy) {
-        /* Release the space on disk */
-        /* (XXX: Nasty usage of internal DXPL value! -QAK) */
-        if(H5MF_xfree(f, H5FD_MEM_OHDR, H5AC_dxpl_id, chk_proxy->oh->chunk[chk_proxy->chunkno].addr, (hsize_t)chk_proxy->oh->chunk[chk_proxy->chunkno].size) < 0)
-            HGOTO_ERROR(H5E_OHDR, H5E_CANTFREE, FAIL, "unable to free object header continuation chunk")
-    } /* end if */
+    /* Serialize messages for this chunk */
+    if(H5O__chunk_serialize(f, chk_proxy->oh, chk_proxy->chunkno) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTSERIALIZE, FAIL, "unable to serialize object header continuation chunk")
 
-    /* Destroy object header chunk proxy */
-    if(H5O__chunk_proxy_dest(chk_proxy) < 0)
-        HGOTO_ERROR(H5E_OHDR, H5E_CANTRELEASE, FAIL, "unable to destroy object header chunk proxy")
+    /* copy the chunk into the image -- this is potentially expensive.
+     * Can we rework things so that the chunk and the cache share a buffer?
+     */
+    HDmemcpy(image, chk_proxy->oh->chunk[chk_proxy->chunkno].image, len);
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5O_cache_chk_dest() */
+} /* end H5O__cache_chk_serialize() */
+
+/**************************************/
+/* no H5O_cache_chk_notify() function */
+/**************************************/
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5O_cache_chk_clear
- *
- * Purpose:	Mark a object header continuation chunk in memory as non-dirty.
- *
- * Return:	Non-negative on success/Negative on failure
- *
- * Programmer:	Quincey Koziol
- *              koziol@hdfgroup.org
- *              July 12, 2008
+ * Function:    H5O__cache_chk_free_icr
  *
- * Changes:     In the parallel case, there is the possibility that the
- *              the object header chunk may be flushed by different
- *              processes over the life of the computation.  Thus we must
- *              ensure that the chunk image is up to date before we mark its
- *              messages clean -- as otherwise we may overwrite valid
- *              data with a blank section of a chunk image.
+ * Purpose:	Free the in core memory associated with the supplied object
+ *		header continuation chunk.
  *
- *              To deal with this, I have added code to call
- *              H5O_chunk_serialize() for this chunk before we
- *              mark all messages as clean if we are not destroying the
- *              chunk.
+ * Note:	The metadata cache sets the object's cache_info.magic to
+ *		H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC before calling a free_icr
+ *		callback (checked in assert).
  *
- *              Do this in the parallel case only, as the problem
- *              can only occur in this context.
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
  *
- *              Note that at present at least, it seems that this fix
- *              is not necessary, as we don't seem to be able to
- *              generate a dirty chunk without creating a dirty object
- *              header.  However, the object header code will be changing
- *              a lot in the near future, so I'll leave this fix in
- *              for now, unless Quincey requests otherwise.
- *
- *                                              JRM -- 10/12/10
+ * Programmer:  John Mainzer
+ *              7/28/14
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5O_cache_chk_clear(H5F_t *f, H5O_chunk_proxy_t *chk_proxy, hbool_t destroy)
+H5O__cache_chk_free_icr(void *_thing)
 {
-    unsigned	u;      /* Local index variable */
-    herr_t ret_value = SUCCEED;
+    H5O_chunk_proxy_t * chk_proxy = (H5O_chunk_proxy_t *)_thing;        /* Object header chunk proxy to release */
+    herr_t              ret_value = SUCCEED;    /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
     /* Check arguments */
     HDassert(chk_proxy);
+    HDassert(chk_proxy->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC);
+    HDassert(chk_proxy->cache_info.type == H5AC_OHDR_CHK);
 
-#ifdef H5_HAVE_PARALLEL
-    if((chk_proxy->oh->cache_info.is_dirty) && (!destroy))
-        if(H5O__chunk_serialize(f, chk_proxy->oh, chk_proxy->chunkno) < 0)
-            HGOTO_ERROR(H5E_OHDR, H5E_CANTSERIALIZE, FAIL, "unable to serialize object header chunk")
-#endif /* H5_HAVE_PARALLEL */
-
-    /* Mark messages in chunk as clean */
-    for(u = 0; u < chk_proxy->oh->nmesgs; u++)
-        if(chk_proxy->oh->mesg[u].chunkno == chk_proxy->chunkno)
-            chk_proxy->oh->mesg[u].dirty = FALSE;
-
-    /* Mark as clean */
-    chk_proxy->cache_info.is_dirty = FALSE;
-
-    if(destroy)
-        if(H5O_cache_chk_dest(f, chk_proxy) < 0)
-            HGOTO_ERROR(H5E_OHDR, H5E_CANTFREE, FAIL, "unable to destroy object header continuation chunk data")
+    /* Destroy object header chunk proxy */
+    if(H5O__chunk_proxy_dest(chk_proxy) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTRELEASE, FAIL, "unable to destroy object header chunk proxy")
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5O_cache_chk_clear() */
+} /* end H5O__cache_chk_free_icr() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5O_cache_chk_size
+ * Function:    H5O__cache_chk_clear
  *
- * Purpose:	Compute the size in bytes of the specified instance of
- *              an object header continuation chunk on disk, and return it in
- *              *len_ptr.  On failure, the value of *len_ptr is undefined.
+ * Purpose: 	Clear all dirty bits associated with this cache entry.
  *
- * Return:	Non-negative on success/Negative on failure
+ *		This is ncessary as the object header cache client maintains 
+ *		its own dirty bits on individual messages.  These dirty bits 
+ *		used to be cleared by the old V2 metadata cache flush callback,
+ *		but now the metadata cache must clear them explicitly, as 
+ *		the serialize callback does not imply that the data has been
+ *		written to disk.
  *
- * Programmer:	Quincey Koziol
- *              koziol@hdfgroup.org
- *              July 12, 2008
+ *		This callback is also necessary for the parallel case.
+ *
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
+ *
+ * Programmer:  John Mainzer
+ *              9/22/14
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5O_cache_chk_size(const H5F_t H5_ATTR_UNUSED *f, const H5O_chunk_proxy_t *chk_proxy, size_t *size_ptr)
-{
-    FUNC_ENTER_NOAPI_NOINIT_NOERR
+H5O__cache_chk_clear(const H5F_t *f, void *_thing, hbool_t about_to_destroy)
+{ 
+    H5O_chunk_proxy_t  *chk_proxy = (H5O_chunk_proxy_t *)_thing;        /* Object header chunk to reset */
+    H5O_t              *oh;                     /* Object header for chunk */
+    unsigned            u;                      /* Local index variable */
+    herr_t              ret_value = SUCCEED;    /* Return value */
 
-    /* check args */
+    FUNC_ENTER_STATIC
+
+    /* Check arguments */
     HDassert(chk_proxy);
-    HDassert(size_ptr);
+    HDassert(chk_proxy->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(chk_proxy->cache_info.type == H5AC_OHDR_CHK);
+    oh = chk_proxy->oh;
+    HDassert(oh);
+    HDassert(oh->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(oh->cache_info.type == H5AC_OHDR);
 
-    /* Report the object header continuation chunk's length */
-    *size_ptr = chk_proxy->oh->chunk[chk_proxy->chunkno].size;
+#ifdef H5_HAVE_PARALLEL
+    if((chk_proxy->oh->cache_info.is_dirty) && (!about_to_destroy))
+        if(H5O__chunk_serialize(f, chk_proxy->oh, chk_proxy->chunkno) < 0)
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTSERIALIZE, FAIL, "unable to serialize object header chunk")
+#endif /* H5_HAVE_PARALLEL */
 
-    FUNC_LEAVE_NOAPI(SUCCEED)
-} /* H5O_cache_chk_size() */
+    /* Mark messages in chunk as clean */
+    for(u = 0; u < chk_proxy->oh->nmesgs; u++)
+        if(chk_proxy->oh->mesg[u].chunkno == chk_proxy->chunkno)
+            chk_proxy->oh->mesg[u].dirty = FALSE;
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O__cache_chk_clear() */
 
 
 /*-------------------------------------------------------------------------
@@ -1024,7 +1043,7 @@ static herr_t
 H5O__chunk_deserialize(H5O_t *oh, haddr_t addr, size_t len, const uint8_t *image,
     H5O_common_cache_ud_t *udata, hbool_t *dirty)
 {
-    const uint8_t *p;           /* Pointer into buffer to decode */
+    const uint8_t *chunk_image; /* Pointer into buffer to decode */
     uint8_t *eom_ptr;           /* Pointer to end of messages for a chunk */
     size_t curmesg;             /* Current message being decoded in object header */
     unsigned merged_null_msgs = 0;  /* Number of null messages merged together */
@@ -1073,18 +1092,18 @@ H5O__chunk_deserialize(H5O_t *oh, haddr_t addr, size_t len, const uint8_t *image
     HDmemcpy(oh->chunk[chunkno].image, image, oh->chunk[chunkno].size);
 
     /* Point into chunk image to decode */
-    p = oh->chunk[chunkno].image;
+    chunk_image = oh->chunk[chunkno].image;
 
     /* Handle chunk 0 as special case */
     if(chunkno == 0)
         /* Skip over [already decoded] prefix */
-        p += (size_t)(H5O_SIZEOF_HDR(oh) - H5O_SIZEOF_CHKSUM_OH(oh));
+        chunk_image += (size_t)(H5O_SIZEOF_HDR(oh) - H5O_SIZEOF_CHKSUM_OH(oh));
     /* Check for magic # on chunks > 0 in later versions of the format */
     else if(chunkno > 0 && oh->version > H5O_VERSION_1) {
         /* Magic number */
-        if(HDmemcmp(p, H5O_CHK_MAGIC, (size_t)H5_SIZEOF_MAGIC))
+        if(HDmemcmp(chunk_image, H5O_CHK_MAGIC, (size_t)H5_SIZEOF_MAGIC))
             HGOTO_ERROR(H5E_OHDR, H5E_CANTLOAD, FAIL, "wrong object header chunk signature")
-        p += H5_SIZEOF_MAGIC;
+        chunk_image += H5_SIZEOF_MAGIC;
     } /* end if */
 
     /* Save # of messages already inspected */
@@ -1095,7 +1114,7 @@ H5O__chunk_deserialize(H5O_t *oh, haddr_t addr, size_t len, const uint8_t *image
 #ifndef NDEBUG
     nullcnt = 0;
 #endif /* NDEBUG */
-    while(p < eom_ptr) {
+    while(chunk_image < eom_ptr) {
         size_t mesgno;          /* Current message to operate on */
         size_t mesg_size;       /* Size of message read in */
         unsigned id;            /* ID (type) of current message */
@@ -1106,20 +1125,20 @@ H5O__chunk_deserialize(H5O_t *oh, haddr_t addr, size_t len, const uint8_t *image
 
         /* Version # */
         if(oh->version == H5O_VERSION_1)
-            UINT16DECODE(p, id)
+            UINT16DECODE(chunk_image, id)
         else
-            id = *p++;
+            id = *chunk_image++;
 
         /* Check for unknown message ID getting encoded in file */
-        if(id == H5O_UNKNOWN_ID)
+        if(id >= H5O_UNKNOWN_ID)
             HGOTO_ERROR(H5E_OHDR, H5E_CANTLOAD, FAIL, "'unknown' message ID encoded in file?!?")
 
         /* Message size */
-        UINT16DECODE(p, mesg_size);
+        UINT16DECODE(chunk_image, mesg_size);
         HDassert(mesg_size == H5O_ALIGN_OH(oh, mesg_size));
 
         /* Message flags */
-        flags = *p++;
+        flags = *chunk_image++;
         if(flags & ~H5O_MSG_FLAG_BITS)
             HGOTO_ERROR(H5E_OHDR, H5E_CANTLOAD, FAIL, "unknown flag for message")
         if((flags & H5O_MSG_FLAG_SHARED) && (flags & H5O_MSG_FLAG_DONTSHARE))
@@ -1131,17 +1150,17 @@ H5O__chunk_deserialize(H5O_t *oh, haddr_t addr, size_t len, const uint8_t *image
 
         /* Reserved bytes/creation index */
         if(oh->version == H5O_VERSION_1)
-            p += 3; /*reserved*/
+            chunk_image += 3; /*reserved*/
         else {
             /* Only decode creation index if they are being tracked */
             if(oh->flags & H5O_HDR_ATTR_CRT_ORDER_TRACKED)
-                UINT16DECODE(p, crt_idx);
+                UINT16DECODE(chunk_image, crt_idx);
         } /* end else */
 
         /* Try to detect invalidly formatted object header message that
          *  extends past end of chunk.
          */
-        if(p + mesg_size > eom_ptr)
+        if(chunk_image + mesg_size > eom_ptr)
             HGOTO_ERROR(H5E_OHDR, H5E_CANTINIT, FAIL, "corrupt object header")
 
 #ifndef NDEBUG
@@ -1177,7 +1196,7 @@ H5O__chunk_deserialize(H5O_t *oh, haddr_t addr, size_t len, const uint8_t *image
             oh->mesg[mesgno].flags = flags;
             oh->mesg[mesgno].crt_idx = crt_idx;
             oh->mesg[mesgno].native = NULL;
-            oh->mesg[mesgno].raw = (uint8_t *)p;        /* Casting away const OK - QAK */
+            oh->mesg[mesgno].raw = (uint8_t *)chunk_image;        /* Casting away const OK - QAK */
             oh->mesg[mesgno].raw_size = mesg_size;
             oh->mesg[mesgno].chunkno = chunkno;
 
@@ -1199,9 +1218,10 @@ H5O__chunk_deserialize(H5O_t *oh, haddr_t addr, size_t len, const uint8_t *image
                 /* Set message to "unknown" class */
                 oh->mesg[mesgno].type = H5O_msg_class_g[H5O_UNKNOWN_ID];
 
-                /* Check for "fail if unknown" message flag */
-                if((udata->file_intent & H5F_ACC_RDWR) && 
-                   (flags & H5O_MSG_FLAG_FAIL_IF_UNKNOWN_AND_OPEN_FOR_WRITE))
+                /* Check for "fail if unknown" message flags */
+                if(((udata->file_intent & H5F_ACC_RDWR) && 
+                       (flags & H5O_MSG_FLAG_FAIL_IF_UNKNOWN_AND_OPEN_FOR_WRITE))
+                        || (flags & H5O_MSG_FLAG_FAIL_IF_UNKNOWN_ALWAYS))
                     HGOTO_ERROR(H5E_OHDR, H5E_BADMESG, FAIL, "unknown message with 'fail if unknown' flag found")
                 /* Check for "mark if unknown" message flag, etc. */
                 else if((flags & H5O_MSG_FLAG_MARK_IF_UNKNOWN) &&
@@ -1233,10 +1253,10 @@ H5O__chunk_deserialize(H5O_t *oh, haddr_t addr, size_t len, const uint8_t *image
         } /* end else */
 
         /* Advance decode pointer past message */
-        p += mesg_size;
+        chunk_image += mesg_size;
 
         /* Check for 'gap' at end of chunk */
-        if((eom_ptr - p) > 0 && (eom_ptr - p) < H5O_SIZEOF_MSGHDR_OH(oh)) {
+        if((eom_ptr - chunk_image) > 0 && (eom_ptr - chunk_image) < H5O_SIZEOF_MSGHDR_OH(oh)) {
             /* Gaps can only occur in later versions of the format */
             HDassert(oh->version > H5O_VERSION_1);
 
@@ -1244,10 +1264,10 @@ H5O__chunk_deserialize(H5O_t *oh, haddr_t addr, size_t len, const uint8_t *image
             HDassert(nullcnt == 0);
 
             /* Set gap information for chunk */
-            oh->chunk[chunkno].gap = (size_t)(eom_ptr - p);
+            oh->chunk[chunkno].gap = (size_t)(eom_ptr - chunk_image);
 
             /* Increment location in chunk */
-            p += oh->chunk[chunkno].gap;
+            chunk_image += oh->chunk[chunkno].gap;
         } /* end if */
     } /* end while */
 
@@ -1257,7 +1277,7 @@ H5O__chunk_deserialize(H5O_t *oh, haddr_t addr, size_t len, const uint8_t *image
         uint32_t computed_chksum;   /* Checksum computed in memory */
 
         /* Metadata checksum */
-        UINT32DECODE(p, stored_chksum);
+        UINT32DECODE(chunk_image, stored_chksum);
 
         /* Compute checksum on chunk */
         computed_chksum = H5_checksum_metadata(oh->chunk[chunkno].image, (oh->chunk[chunkno].size - H5O_SIZEOF_CHKSUM), 0);
@@ -1268,7 +1288,7 @@ H5O__chunk_deserialize(H5O_t *oh, haddr_t addr, size_t len, const uint8_t *image
     } /* end if */
 
     /* Sanity check */
-    HDassert(p == oh->chunk[chunkno].image + oh->chunk[chunkno].size);
+    HDassert(chunk_image == oh->chunk[chunkno].image + oh->chunk[chunkno].size);
 
     /* Do some inspection/interpretation of new messages from this chunk */
     /* (detect continuation messages, ref. count messages, etc.) */
@@ -1390,7 +1410,7 @@ H5O__chunk_serialize(const H5F_t *f, H5O_t *oh, unsigned chunkno)
     /* Extra work, for later versions of the format */
     if(oh->version > H5O_VERSION_1) {
         uint32_t metadata_chksum;   /* Computed metadata checksum value */
-        uint8_t	*p;                 /* Pointer into object header chunk */
+        uint8_t	*chunk_image;       /* Pointer into object header chunk */
 
         /* Check for gap in chunk & zero it out */
         if(oh->chunk[chunkno].gap)
@@ -1401,8 +1421,8 @@ H5O__chunk_serialize(const H5F_t *f, H5O_t *oh, unsigned chunkno)
         metadata_chksum = H5_checksum_metadata(oh->chunk[chunkno].image, (oh->chunk[chunkno].size - H5O_SIZEOF_CHKSUM), 0);
 
         /* Metadata checksum */
-        p = oh->chunk[chunkno].image + (oh->chunk[chunkno].size - H5O_SIZEOF_CHKSUM);
-        UINT32ENCODE(p, metadata_chksum);
+        chunk_image = oh->chunk[chunkno].image + (oh->chunk[chunkno].size - H5O_SIZEOF_CHKSUM);
+        UINT32ENCODE(chunk_image, metadata_chksum);
     } /* end if */
 
 done:
@@ -1443,5 +1463,5 @@ H5O__chunk_proxy_dest(H5O_chunk_proxy_t *chk_proxy)
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* H5O_chunk_proxy_dest() */
+} /* H5O__chunk_proxy_dest() */
 
diff --git a/src/H5Ochunk.c b/src/H5Ochunk.c
index 41d3f66..bb82ad1 100644
--- a/src/H5Ochunk.c
+++ b/src/H5Ochunk.c
@@ -184,7 +184,7 @@ H5O_chunk_protect(H5F_t *f, hid_t dxpl_id, H5O_t *oh, unsigned idx)
         chk_udata.size = oh->chunk[idx].size;
 
         /* Get the chunk proxy */
-        if(NULL == (chk_proxy = (H5O_chunk_proxy_t *)H5AC_protect(f, dxpl_id, H5AC_OHDR_CHK, oh->chunk[idx].addr, &chk_udata, H5AC_WRITE)))
+        if(NULL == (chk_proxy = (H5O_chunk_proxy_t *)H5AC_protect(f, dxpl_id, H5AC_OHDR_CHK, oh->chunk[idx].addr, &chk_udata, H5AC__NO_FLAGS_SET)))
             HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, NULL, "unable to load object header chunk")
 
         /* Sanity check */
@@ -337,7 +337,7 @@ H5O_chunk_update_idx(H5F_t *f, hid_t dxpl_id, H5O_t *oh, unsigned idx)
     chk_udata.size = oh->chunk[idx].size;
 
     /* Get the chunk proxy */
-    if(NULL == (chk_proxy = (H5O_chunk_proxy_t *)H5AC_protect(f, dxpl_id, H5AC_OHDR_CHK, oh->chunk[idx].addr, &chk_udata, H5AC_WRITE)))
+    if(NULL == (chk_proxy = (H5O_chunk_proxy_t *)H5AC_protect(f, dxpl_id, H5AC_OHDR_CHK, oh->chunk[idx].addr, &chk_udata, H5AC__NO_FLAGS_SET)))
         HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to load object header chunk")
 
     /* Update index for chunk proxy in cache */
@@ -389,7 +389,7 @@ H5O_chunk_delete(H5F_t *f, hid_t dxpl_id, H5O_t *oh, unsigned idx)
     chk_udata.size = oh->chunk[idx].size;
 
     /* Get the chunk proxy */
-    if(NULL == (chk_proxy = (H5O_chunk_proxy_t *)H5AC_protect(f, dxpl_id, H5AC_OHDR_CHK, oh->chunk[idx].addr, &chk_udata, H5AC_WRITE)))
+    if(NULL == (chk_proxy = (H5O_chunk_proxy_t *)H5AC_protect(f, dxpl_id, H5AC_OHDR_CHK, oh->chunk[idx].addr, &chk_udata, H5AC__NO_FLAGS_SET)))
         HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to load object header chunk")
 
     /* Sanity check */
diff --git a/src/H5Ocopy.c b/src/H5Ocopy.c
index afd8e94..66322da 100644
--- a/src/H5Ocopy.c
+++ b/src/H5Ocopy.c
@@ -379,7 +379,7 @@ H5O_copy_header_real(const H5O_loc_t *oloc_src, H5O_loc_t *oloc_dst /*out*/,
     }
 
     /* Get source object header */
-    if(NULL == (oh_src = H5O_protect(oloc_src, dxpl_id, H5AC_READ)))
+    if(NULL == (oh_src = H5O_protect(oloc_src, dxpl_id, H5AC__READ_ONLY_FLAG)))
         HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to load object header")
 
     /* Retrieve user data for particular type of object to copy */
diff --git a/src/H5Odbg.c b/src/H5Odbg.c
index 0531a90..0388cd5 100644
--- a/src/H5Odbg.c
+++ b/src/H5Odbg.c
@@ -566,7 +566,7 @@ H5O_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE *stream, int indent, int f
     loc.addr = addr;
     loc.holding_file = FALSE;
 
-    if(NULL == (oh = H5O_protect(&loc, dxpl_id, H5AC_READ)))
+    if(NULL == (oh = H5O_protect(&loc, dxpl_id, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to load object header")
 
     /* debug */
diff --git a/src/H5Oefl.c b/src/H5Oefl.c
index e37e9b7..a7ce31a 100644
--- a/src/H5Oefl.c
+++ b/src/H5Oefl.c
@@ -128,7 +128,7 @@ H5O_efl_decode(H5F_t *f, hid_t dxpl_id, H5O_t H5_ATTR_UNUSED *open_oh,
 #ifndef NDEBUG
     HDassert(H5F_addr_defined(mesg->heap_addr));
 
-    if(NULL == (heap = H5HL_protect(f, dxpl_id, mesg->heap_addr, H5AC_READ)))
+    if(NULL == (heap = H5HL_protect(f, dxpl_id, mesg->heap_addr, H5AC__READ_ONLY_FLAG)))
         HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, NULL, "unable to read protect link value")
 
     s = (const char *)H5HL_offset_into(heap, 0);
@@ -145,7 +145,7 @@ H5O_efl_decode(H5F_t *f, hid_t dxpl_id, H5O_t H5_ATTR_UNUSED *open_oh,
     if(NULL == mesg->slot)
 	HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed")
 
-    if(NULL == (heap = H5HL_protect(f, dxpl_id, mesg->heap_addr, H5AC_READ)))
+    if(NULL == (heap = H5HL_protect(f, dxpl_id, mesg->heap_addr, H5AC__READ_ONLY_FLAG)))
         HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, NULL, "unable to read protect link value")
     for(u = 0; u < mesg->nused; u++) {
 	/* Name */
@@ -487,7 +487,7 @@ H5O_efl_copy_file(H5F_t H5_ATTR_UNUSED *file_src, void *mesg_src, H5F_t *file_ds
         HGOTO_ERROR(H5E_EFL, H5E_CANTINIT, NULL, "can't create heap")
 
     /* Pin the heap down in memory */
-    if(NULL == (heap = H5HL_protect(file_dst, dxpl_id, efl_dst->heap_addr, H5AC_WRITE)))
+    if(NULL == (heap = H5HL_protect(file_dst, dxpl_id, efl_dst->heap_addr, H5AC__NO_FLAGS_SET)))
         HGOTO_ERROR(H5E_EFL, H5E_PROTECT, NULL, "unable to protect EFL file name heap")
 
     /* Insert "empty" name first */
diff --git a/src/H5Omessage.c b/src/H5Omessage.c
index d361194..c2756ea 100644
--- a/src/H5Omessage.c
+++ b/src/H5Omessage.c
@@ -476,7 +476,7 @@ H5O_msg_read(const H5O_loc_t *loc, unsigned type_id, void *mesg,
     HDassert(type_id < NELMTS(H5O_msg_class_g));
 
     /* Get the object header */
-    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC_READ)))
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, NULL, "unable to protect object header")
 
     /* Call the "real" read routine */
@@ -802,7 +802,7 @@ H5O_msg_count(const H5O_loc_t *loc, unsigned type_id, hid_t dxpl_id)
     HDassert(type);
 
     /* Load the object header */
-    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC_READ)))
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to protect object header")
 
     /* Count the messages of the correct type */
@@ -884,7 +884,7 @@ H5O_msg_exists(const H5O_loc_t *loc, unsigned type_id, hid_t dxpl_id)
     HDassert(type_id < NELMTS(H5O_msg_class_g));
 
     /* Load the object header */
-    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC_READ)))
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to protect object header")
 
     /* Call the "real" exists routine */
@@ -1224,7 +1224,7 @@ H5O_msg_iterate(const H5O_loc_t *loc, unsigned type_id,
     HDassert(op);
 
     /* Protect the object header to iterate over */
-    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC_READ)))
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to protect object header")
 
     /* Call the "real" iterate routine */
@@ -2289,7 +2289,7 @@ H5O_msg_get_chunkno(const H5O_loc_t *loc, unsigned type_id, hid_t dxpl_id)
     HDassert(type);
 
     /* Get the object header */
-    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC_READ)))
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to protect object header")
 
     /* Locate message of correct type */
@@ -2344,7 +2344,7 @@ H5O_msg_lock(const H5O_loc_t *loc, unsigned type_id, hid_t dxpl_id)
     HDassert(type);
 
     /* Get the object header */
-    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC_READ)))
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to protect object header")
 
     /* Locate message of correct type */
@@ -2402,7 +2402,7 @@ H5O_msg_unlock(const H5O_loc_t *loc, unsigned type_id, hid_t dxpl_id)
     HDassert(type);
 
     /* Get the object header */
-    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC_READ)))
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to protect object header")
 
     /* Locate message of correct type */
diff --git a/src/H5Oprivate.h b/src/H5Oprivate.h
index cc262a0..dbe74f7 100644
--- a/src/H5Oprivate.h
+++ b/src/H5Oprivate.h
@@ -75,7 +75,8 @@ typedef struct H5O_t H5O_t;
 #define H5O_MSG_FLAG_MARK_IF_UNKNOWN 0x10u
 #define H5O_MSG_FLAG_WAS_UNKNOWN 0x20u
 #define H5O_MSG_FLAG_SHAREABLE  0x40u
-#define H5O_MSG_FLAG_BITS	(H5O_MSG_FLAG_CONSTANT|H5O_MSG_FLAG_SHARED|H5O_MSG_FLAG_DONTSHARE|H5O_MSG_FLAG_FAIL_IF_UNKNOWN_AND_OPEN_FOR_WRITE|H5O_MSG_FLAG_MARK_IF_UNKNOWN|H5O_MSG_FLAG_WAS_UNKNOWN|H5O_MSG_FLAG_SHAREABLE)
+#define H5O_MSG_FLAG_FAIL_IF_UNKNOWN_ALWAYS 0x80u
+#define H5O_MSG_FLAG_BITS	(H5O_MSG_FLAG_CONSTANT|H5O_MSG_FLAG_SHARED|H5O_MSG_FLAG_DONTSHARE|H5O_MSG_FLAG_FAIL_IF_UNKNOWN_AND_OPEN_FOR_WRITE|H5O_MSG_FLAG_MARK_IF_UNKNOWN|H5O_MSG_FLAG_WAS_UNKNOWN|H5O_MSG_FLAG_SHAREABLE|H5O_MSG_FLAG_FAIL_IF_UNKNOWN_ALWAYS)
 
 /* Flags for updating messages */
 #define H5O_UPDATE_TIME         0x01u
@@ -84,6 +85,9 @@ typedef struct H5O_t H5O_t;
 /* Hash value constants */
 #define H5O_HASH_SIZE 32
 
+/* Enable reading/writing "bogus" messages */
+/* #define H5O_ENABLE_BOGUS */
+
 /* ========= Object Creation properties ============ */
 #define H5O_CRT_ATTR_MAX_COMPACT_NAME	"max compact attr"      /* Max. # of attributes to store compactly */
 #define H5O_CRT_ATTR_MIN_DENSE_NAME	"min dense attr"	/* Min. # of attributes to store densely */
@@ -196,7 +200,6 @@ typedef struct H5O_copy_t {
 #define H5O_UNKNOWN_ID  0x0018          /* Placeholder message ID for unknown message.  */
                                         /* (this should never exist in a file) */
 
-
 /* Shared object message types.
  * Shared objects can be committed, in which case the shared message contains
  * the location of the object header that holds the message, or shared in the
@@ -439,9 +442,6 @@ typedef struct H5O_layout_t {
     H5O_storage_t storage;              /* Information for storing dataset elements */
 } H5O_layout_t;
 
-/* Enable reading/writing "bogus" messages */
-/* #define H5O_ENABLE_BOGUS */
-
 #ifdef H5O_ENABLE_BOGUS
 /*
  * "Bogus" Message.
@@ -564,6 +564,8 @@ typedef struct H5O_btreek_t {
  * (Data structure in memory)
  */
 typedef struct H5O_drvinfo_t {
+/* Information for H5AC cache functions, _must_ be first field in structure */
+    H5AC_info_t         cache_info;
     char                name[9];                /* Driver name */
     size_t		len;                    /* Length of encoded buffer */
     uint8_t            *buf;                    /* Buffer for encoded info */
@@ -659,7 +661,7 @@ H5_DLL herr_t H5O_create(H5F_t *f, hid_t dxpl_id, size_t size_hint,
 H5_DLL herr_t H5O_open(H5O_loc_t *loc);
 H5_DLL herr_t H5O_close(H5O_loc_t *loc);
 H5_DLL int H5O_link(const H5O_loc_t *loc, int adjust, hid_t dxpl_id);
-H5_DLL H5O_t *H5O_protect(const H5O_loc_t *loc, hid_t dxpl_id, H5AC_protect_t prot);
+H5_DLL H5O_t *H5O_protect(const H5O_loc_t *loc, hid_t dxpl_id, unsigned prot_flags);
 H5_DLL H5O_t *H5O_pin(const H5O_loc_t *loc, hid_t dxpl_id);
 H5_DLL herr_t H5O_unpin(H5O_t *oh);
 H5_DLL herr_t H5O_dec_rc_by_loc(const H5O_loc_t *loc, hid_t dxpl_id);
diff --git a/src/H5Oshared.h b/src/H5Oshared.h
index 3ec5709..2ac2a98 100644
--- a/src/H5Oshared.h
+++ b/src/H5Oshared.h
@@ -47,7 +47,7 @@
  *
  *-------------------------------------------------------------------------
  */
-static H5_inline void *
+static H5_INLINE void *
 H5O_SHARED_DECODE(H5F_t *f, hid_t dxpl_id, H5O_t *open_oh, unsigned mesg_flags,
     unsigned *ioflags, const uint8_t *p)
 {
@@ -107,7 +107,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-static H5_inline herr_t
+static H5_INLINE herr_t
 H5O_SHARED_ENCODE(H5F_t *f, hbool_t disable_shared, uint8_t *p, const void *_mesg)
 {
     const H5O_shared_t *sh_mesg = (const H5O_shared_t *)_mesg;     /* Pointer to shared message portion of actual message */
@@ -162,7 +162,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-static H5_inline size_t
+static H5_INLINE size_t
 H5O_SHARED_SIZE(const H5F_t *f, hbool_t disable_shared, const void *_mesg)
 {
     const H5O_shared_t *sh_mesg = (const H5O_shared_t *)_mesg;     /* Pointer to shared message portion of actual message */
@@ -215,7 +215,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-static H5_inline herr_t
+static H5_INLINE herr_t
 H5O_SHARED_DELETE(H5F_t *f, hid_t dxpl_id, H5O_t *open_oh, void *_mesg)
 {
     H5O_shared_t *sh_mesg = (H5O_shared_t *)_mesg;     /* Pointer to shared message portion of actual message */
@@ -267,7 +267,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-static H5_inline herr_t
+static H5_INLINE herr_t
 H5O_SHARED_LINK(H5F_t *f, hid_t dxpl_id, H5O_t *open_oh, void *_mesg)
 {
     H5O_shared_t *sh_mesg = (H5O_shared_t *)_mesg;     /* Pointer to shared message portion of actual message */
@@ -318,7 +318,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-static H5_inline void *
+static H5_INLINE void *
 H5O_SHARED_COPY_FILE(H5F_t *file_src, void *_native_src, H5F_t *file_dst,
     hbool_t *recompute_size, unsigned *mesg_flags, H5O_copy_t *cpy_info,
     void *udata, hid_t dxpl_id)
@@ -382,7 +382,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-static H5_inline herr_t
+static H5_INLINE herr_t
 H5O_SHARED_POST_COPY_FILE(const H5O_loc_t *oloc_src, const void *mesg_src,
     H5O_loc_t *oloc_dst, void *mesg_dst, unsigned *mesg_flags, hid_t dxpl_id,
     H5O_copy_t *cpy_info)
@@ -453,7 +453,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-static H5_inline herr_t
+static H5_INLINE herr_t
 H5O_SHARED_DEBUG(H5F_t *f, hid_t dxpl_id, const void *_mesg, FILE *stream,
     int indent, int fwidth)
 {
diff --git a/src/H5Otest.c b/src/H5Otest.c
index d1627ef..e7312ee 100644
--- a/src/H5Otest.c
+++ b/src/H5Otest.c
@@ -108,7 +108,7 @@ H5O_is_attr_dense_test(hid_t oid)
         HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, FAIL, "object not found")
 
     /* Get the object header */
-    if(NULL == (oh = H5O_protect(loc, H5AC_ind_dxpl_id, H5AC_READ)))
+    if(NULL == (oh = H5O_protect(loc, H5AC_ind_dxpl_id, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to load object header")
 
     /* Check for attribute info stored */
@@ -173,7 +173,7 @@ H5O_is_attr_empty_test(hid_t oid)
         HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, FAIL, "object not found")
 
     /* Get the object header */
-    if(NULL == (oh = H5O_protect(loc, H5AC_ind_dxpl_id, H5AC_READ)))
+    if(NULL == (oh = H5O_protect(loc, H5AC_ind_dxpl_id, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to load object header")
 
     /* Check for attribute info stored */
@@ -266,7 +266,7 @@ H5O_num_attrs_test(hid_t oid, hsize_t *nattrs)
         HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, FAIL, "object not found")
 
     /* Get the object header */
-    if(NULL == (oh = H5O_protect(loc, H5AC_ind_dxpl_id, H5AC_READ)))
+    if(NULL == (oh = H5O_protect(loc, H5AC_ind_dxpl_id, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to load object header")
 
     /* Check for attribute info stored */
@@ -361,7 +361,7 @@ H5O_attr_dense_info_test(hid_t oid, hsize_t *name_count, hsize_t *corder_count)
     H5_BEGIN_TAG(H5AC_ind_dxpl_id, loc->addr, FAIL);
 
     /* Get the object header */
-    if(NULL == (oh = H5O_protect(loc, H5AC_ind_dxpl_id, H5AC_READ)))
+    if(NULL == (oh = H5O_protect(loc, H5AC_ind_dxpl_id, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR_TAG(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to load object header")
 
     /* Check for attribute info stored */
@@ -452,7 +452,7 @@ H5O_check_msg_marked_test(hid_t oid, hbool_t flag_val)
         HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, FAIL, "object not found")
 
     /* Get the object header */
-    if(NULL == (oh = H5O_protect(loc, H5AC_ind_dxpl_id, H5AC_READ)))
+    if(NULL == (oh = H5O_protect(loc, H5AC_ind_dxpl_id, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to load object header")
 
     /* Locate "unknown" message  */
@@ -511,7 +511,7 @@ H5O_expunge_chunks_test(const H5O_loc_t *loc, hid_t dxpl_id)
     FUNC_ENTER_NOAPI(FAIL)
 
     /* Get the object header */
-    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC_WRITE)))
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__NO_FLAGS_SET)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to protect object header")
 
     /* Safety check */
@@ -571,7 +571,7 @@ H5O_get_rc(const H5O_loc_t *loc, hid_t dxpl_id, unsigned *rc)
     HDassert(rc);
 
     /* Get the object header */
-    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC_READ)))
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to protect object header")
 
     /* Save the refcount for the object header */
diff --git a/src/H5Plapl.c b/src/H5Plapl.c
index 87b96b6..e3b3c4f 100644
--- a/src/H5Plapl.c
+++ b/src/H5Plapl.c
@@ -237,7 +237,7 @@ H5P_lacc_elink_fapl_enc(const void *value, void **_pp, size_t *size)
     uint8_t **pp = (uint8_t **)_pp;
     H5P_genplist_t *fapl_plist;         /* Pointer to property list */
     hbool_t non_default_fapl = FALSE;   /* Whether the FAPL is non-default */
-    size_t enc_size = 0;                /* FAPL's encoded size */
+    size_t fapl_size = 0;                /* FAPL's encoded size */
     herr_t ret_value = SUCCEED;         /* Return value */
 
     FUNC_ENTER_NOAPI_NOINIT
@@ -257,13 +257,30 @@ H5P_lacc_elink_fapl_enc(const void *value, void **_pp, size_t *size)
     /* Encode the property list, if non-default */
     /* (if *pp == NULL, will only compute the size) */
     if(non_default_fapl) {
-        if(H5P__encode(fapl_plist, TRUE, *pp, &enc_size) < 0)
+        if(H5P__encode(fapl_plist, TRUE, NULL, &fapl_size) < 0)
             HGOTO_ERROR(H5E_PLIST, H5E_CANTENCODE, FAIL, "can't encode property list")
-        if(*pp)
-            *pp += enc_size;
+
+        if(*pp) {
+            uint64_t enc_value;
+            unsigned enc_size;
+
+            /* encode the length of the plist */
+            enc_value = (uint64_t)fapl_size;
+            enc_size = H5VM_limit_enc_size(enc_value);
+            HDassert(enc_size < 256);
+            *(*pp)++ = (uint8_t)enc_size;
+            UINT64ENCODE_VAR(*pp, enc_value, enc_size);
+
+            /* encode the plist */
+            if(H5P__encode(fapl_plist, TRUE, *pp, &fapl_size) < 0)
+                HGOTO_ERROR(H5E_PLIST, H5E_CANTENCODE, FAIL, "can't encode property list")
+
+            *pp += fapl_size;
+        }
+        fapl_size += (1 + H5VM_limit_enc_size((uint64_t)fapl_size));
     } /* end if */
 
-    *size += (1 + enc_size);      /* Non-default flag, plus encoded property list size */
+    *size += (1 + fapl_size);      /* Non-default flag, plus encoded property list size */
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
@@ -304,22 +321,21 @@ H5P_lacc_elink_fapl_dec(const void **_pp, void *_value)
     non_default_fapl = (hbool_t)*(*pp)++;
 
     if(non_default_fapl) {
-        H5P_genplist_t *fapl_plist;         /* Pointer to property list */
-        size_t enc_size = 0;                /* Encoded size of property list */
+        size_t fapl_size = 0;                /* Encoded size of property list */
+        unsigned enc_size;
+        uint64_t enc_value;
+
+        /* Decode the plist length */
+        enc_size = *(*pp)++;
+        HDassert(enc_size < 256);
+        UINT64DECODE_VAR(*pp, enc_value, enc_size);
+        fapl_size = (size_t)enc_value;
 
         /* Decode the property list */
         if((*elink_fapl = H5P__decode(*pp)) < 0)
             HGOTO_ERROR(H5E_PLIST, H5E_CANTDECODE, FAIL, "can't decode property")
 
-        /* Get the property list object */
-        if(NULL == (fapl_plist = (H5P_genplist_t *)H5P_object_verify(*elink_fapl, H5P_FILE_ACCESS)))
-            HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, FAIL, "can't get property list")
-
-        /* Compute the encoded size of the property list */
-        if(H5P__encode(fapl_plist, TRUE, NULL, &enc_size) < 0)
-            HGOTO_ERROR(H5E_PLIST, H5E_CANTENCODE, FAIL, "can't compute encoded property list size")
-
-        *pp += enc_size;
+        *pp += fapl_size;
     } /* end if */
     else
         *elink_fapl = H5P_DEFAULT;
@@ -578,7 +594,7 @@ H5P_lacc_elink_pref_dec(const void **_pp, void *_value)
 
     /* Decode the value */
     UINT64DECODE_VAR(*pp, enc_value, enc_size);
-    len = enc_value;
+    len = (size_t)enc_value;
 
     if(0 != len) {
         /* Make a copy of the user's prefix string */
diff --git a/src/H5SM.c b/src/H5SM.c
index abdb109..1d391f1 100644
--- a/src/H5SM.c
+++ b/src/H5SM.c
@@ -358,7 +358,7 @@ H5SM_type_shared(H5F_t *f, unsigned type_id, hid_t dxpl_id)
         /* Set up user data for callback */
         cache_udata.f = f;
 
-        if(NULL == (table = (H5SM_master_table_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_TABLE, H5F_SOHM_ADDR(f), &cache_udata, H5AC_READ)))
+        if(NULL == (table = (H5SM_master_table_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_TABLE, H5F_SOHM_ADDR(f), &cache_udata, H5AC__READ_ONLY_FLAG)))
             HGOTO_ERROR(H5E_SOHM, H5E_CANTPROTECT, FAIL, "unable to load SOHM master table")
     } /* end if */
     else
@@ -412,7 +412,7 @@ H5SM_get_fheap_addr(H5F_t *f, hid_t dxpl_id, unsigned type_id, haddr_t *fheap_ad
     cache_udata.f = f;
 
     /* Look up the master SOHM table */
-    if(NULL == (table = (H5SM_master_table_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_TABLE, H5F_SOHM_ADDR(f), &cache_udata, H5AC_READ)))
+    if(NULL == (table = (H5SM_master_table_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_TABLE, H5F_SOHM_ADDR(f), &cache_udata, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_SOHM, H5E_CANTPROTECT, FAIL, "unable to load SOHM master table")
 
     /* Look up index for message type */
@@ -831,7 +831,7 @@ H5SM_convert_btree_to_list(H5F_t * f, H5SM_index_header_t * header, hid_t dxpl_i
     cache_udata.header = header;
 
     /* Protect the SOHM list */
-    if(NULL == (list = (H5SM_list_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_LIST, header->index_addr, &cache_udata, H5AC_WRITE)))
+    if(NULL == (list = (H5SM_list_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_LIST, header->index_addr, &cache_udata, H5AC__NO_FLAGS_SET)))
         HGOTO_ERROR(H5E_SOHM, H5E_CANTPROTECT, FAIL, "unable to load SOHM list index")
 
     /* Delete the B-tree and have messages copy themselves to the
@@ -939,7 +939,7 @@ H5SM_can_share(H5F_t *f, hid_t dxpl_id, H5SM_master_table_t *table,
         /* Set up user data for callback */
         cache_udata.f = f;
 
-        if(NULL == (my_table = (H5SM_master_table_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_TABLE, H5F_SOHM_ADDR(f), &cache_udata, H5AC_READ)))
+        if(NULL == (my_table = (H5SM_master_table_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_TABLE, H5F_SOHM_ADDR(f), &cache_udata, H5AC__READ_ONLY_FLAG)))
             HGOTO_ERROR(H5E_SOHM, H5E_CANTPROTECT, FAIL, "unable to load SOHM master table")
     } /* end if */
 
@@ -1071,7 +1071,7 @@ H5SM_try_share(H5F_t *f, hid_t dxpl_id, H5O_t *open_oh, unsigned defer_flags,
     cache_udata.f = f;
 
     /* Look up the master SOHM table */
-    if(NULL == (table = (H5SM_master_table_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_TABLE, H5F_SOHM_ADDR(f), &cache_udata, H5AC_WRITE)))
+    if(NULL == (table = (H5SM_master_table_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_TABLE, H5F_SOHM_ADDR(f), &cache_udata, H5AC__NO_FLAGS_SET)))
 	HGOTO_ERROR(H5E_SOHM, H5E_CANTPROTECT, FAIL, "unable to load SOHM master table")
 
     /* "complex" sharing checks */
@@ -1277,7 +1277,7 @@ H5SM_write_mesg(H5F_t *f, hid_t dxpl_id, H5O_t *open_oh,
         cache_udata.header = header;
 
         /* The index is a list; get it from the cache */
-        if(NULL == (list = (H5SM_list_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_LIST, header->index_addr, &cache_udata, defer ? H5AC_READ : H5AC_WRITE)))
+        if(NULL == (list = (H5SM_list_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_LIST, header->index_addr, &cache_udata, defer ? H5AC__READ_ONLY_FLAG : H5AC__NO_FLAGS_SET)))
 	    HGOTO_ERROR(H5E_SOHM, H5E_CANTPROTECT, FAIL, "unable to load SOHM index")
 
         /* See if the message is already in the index and get its location.
@@ -1530,7 +1530,7 @@ H5SM_delete(H5F_t *f, hid_t dxpl_id, H5O_t *open_oh, H5O_shared_t *sh_mesg)
     cache_udata.f = f;
 
     /* Look up the master SOHM table */
-    if(NULL == (table = (H5SM_master_table_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_TABLE, H5F_SOHM_ADDR(f), &cache_udata, H5AC_WRITE)))
+    if(NULL == (table = (H5SM_master_table_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_TABLE, H5F_SOHM_ADDR(f), &cache_udata, H5AC__NO_FLAGS_SET)))
 	HGOTO_ERROR(H5E_SOHM, H5E_CANTPROTECT, FAIL, "unable to load SOHM master table")
 
     /* Find the correct index and try to delete from it */
@@ -1799,7 +1799,7 @@ H5SM_delete_from_index(H5F_t *f, hid_t dxpl_id, H5O_t *open_oh,
         cache_udata.header = header;
 
         /* If the index is stored as a list, get it from the cache */
-        if(NULL == (list = (H5SM_list_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_LIST, header->index_addr, &cache_udata, H5AC_WRITE)))
+        if(NULL == (list = (H5SM_list_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_LIST, header->index_addr, &cache_udata, H5AC__NO_FLAGS_SET)))
 	    HGOTO_ERROR(H5E_SOHM, H5E_CANTPROTECT, FAIL, "unable to load SOHM index")
 
         /* Find the message in the list */
@@ -1970,7 +1970,7 @@ H5SM_get_info(const H5O_loc_t *ext_loc, H5P_genplist_t *fc_plist, hid_t dxpl_id)
         cache_udata.f = f;
 
         /* Read the rest of the SOHM table information from the cache */
-        if(NULL == (table = (H5SM_master_table_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_TABLE, H5F_SOHM_ADDR(f), &cache_udata, H5AC_READ)))
+        if(NULL == (table = (H5SM_master_table_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_TABLE, H5F_SOHM_ADDR(f), &cache_udata, H5AC__READ_ONLY_FLAG)))
             HGOTO_ERROR(H5E_SOHM, H5E_CANTPROTECT, FAIL, "unable to load SOHM master table")
 
         /* Get index conversion limits */
@@ -2133,7 +2133,7 @@ H5SM_get_refcount(H5F_t *f, hid_t dxpl_id, unsigned type_id,
     tbl_cache_udata.f = f;
 
     /* Look up the master SOHM table */
-    if(NULL == (table = (H5SM_master_table_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_TABLE, H5F_SOHM_ADDR(f), &tbl_cache_udata, H5AC_READ)))
+    if(NULL == (table = (H5SM_master_table_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_TABLE, H5F_SOHM_ADDR(f), &tbl_cache_udata, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_SOHM, H5E_CANTPROTECT, FAIL, "unable to load SOHM master table")
 
     /* Find the correct index and find the message in it */
@@ -2172,7 +2172,7 @@ H5SM_get_refcount(H5F_t *f, hid_t dxpl_id, unsigned type_id,
         lst_cache_udata.header = header;
 
         /* If the index is stored as a list, get it from the cache */
-        if(NULL == (list = (H5SM_list_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_LIST, header->index_addr, &lst_cache_udata, H5AC_READ)))
+        if(NULL == (list = (H5SM_list_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_LIST, header->index_addr, &lst_cache_udata, H5AC__READ_ONLY_FLAG)))
 	    HGOTO_ERROR(H5E_SOHM, H5E_CANTPROTECT, FAIL, "unable to load SOHM index")
 
         /* Find the message in the list */
@@ -2375,7 +2375,7 @@ H5SM_read_mesg(H5F_t *f, const H5SM_sohm_t *mesg, H5HF_t *fheap,
 	        HGOTO_ERROR(H5E_SOHM, H5E_CANTLOAD, FAIL, "unable to open object header")
 
             /* Load the object header from the cache */
-            if(NULL == (oh = H5O_protect(&oloc, dxpl_id, H5AC_READ)))
+            if(NULL == (oh = H5O_protect(&oloc, dxpl_id, H5AC__READ_ONLY_FLAG)))
 	        HGOTO_ERROR(H5E_SOHM, H5E_CANTPROTECT, FAIL, "unable to load object header")
         } /* end if */
         else
@@ -2530,7 +2530,7 @@ H5SM_table_debug(H5F_t *f, hid_t dxpl_id, haddr_t table_addr,
     cache_udata.f = f;
 
     /* Look up the master SOHM table */
-    if(NULL == (table = (H5SM_master_table_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_TABLE, table_addr, &cache_udata, H5AC_READ)))
+    if(NULL == (table = (H5SM_master_table_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_TABLE, table_addr, &cache_udata, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_SOHM, H5E_CANTPROTECT, FAIL, "unable to load SOHM master table")
 
     HDfprintf(stream, "%*sShared Message Master Table...\n", indent, "");
@@ -2616,7 +2616,7 @@ H5SM_list_debug(H5F_t *f, hid_t dxpl_id, haddr_t list_addr,
     cache_udata.header = &header;
 
     /* Get the list from the cache */
-    if(NULL == (list = (H5SM_list_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_LIST, list_addr, &cache_udata, H5AC_READ)))
+    if(NULL == (list = (H5SM_list_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_LIST, list_addr, &cache_udata, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_SOHM, H5E_CANTPROTECT, FAIL, "unable to load SOHM index")
 
     HDfprintf(stream, "%*sShared Message List Index...\n", indent, "");
@@ -2693,7 +2693,7 @@ H5SM_ih_size(H5F_t *f, hid_t dxpl_id, hsize_t *hdr_size, H5_ih_info_t *ih_info)
     cache_udata.f = f;
 
     /* Look up the master SOHM table */
-    if(NULL == (table = (H5SM_master_table_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_TABLE, H5F_SOHM_ADDR(f), &cache_udata, H5AC_READ)))
+    if(NULL == (table = (H5SM_master_table_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_TABLE, H5F_SOHM_ADDR(f), &cache_udata, H5AC__READ_ONLY_FLAG)))
 	HGOTO_ERROR(H5E_SOHM, H5E_CANTPROTECT, FAIL, "unable to load SOHM master table")
 
     /* Get SOHM header size */
diff --git a/src/H5SMcache.c b/src/H5SMcache.c
index eaeb889..293088c 100644
--- a/src/H5SMcache.c
+++ b/src/H5SMcache.c
@@ -47,12 +47,6 @@
 /* Local Macros */
 /****************/
 
-/* Size of stack buffer for serialized tables */
-#define H5SM_TBL_BUF_SIZE       1024
-
-/* Size of stack buffer for serialized list indices */
-#define H5SM_LST_BUF_SIZE       1024
-
 
 /******************/
 /* Local Typedefs */
@@ -64,16 +58,23 @@
 /********************/
 
 /* Metadata cache (H5AC) callbacks */
-static H5SM_master_table_t *H5SM_table_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata);
-static herr_t H5SM_table_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5SM_master_table_t *table);
-static herr_t H5SM_table_dest(H5F_t *f, H5SM_master_table_t* table);
-static herr_t H5SM_table_clear(H5F_t *f, H5SM_master_table_t *table, hbool_t destroy);
-static herr_t H5SM_table_size(const H5F_t *f, const H5SM_master_table_t *table, size_t *size_ptr);
-static H5SM_list_t *H5SM_list_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *udata);
-static herr_t H5SM_list_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5SM_list_t *list);
-static herr_t H5SM_list_dest(H5F_t *f, H5SM_list_t* list);
-static herr_t H5SM_list_clear(H5F_t *f, H5SM_list_t *list, hbool_t destroy);
-static herr_t H5SM_list_size(const H5F_t *f, const H5SM_list_t H5_ATTR_UNUSED *list, size_t *size_ptr);
+static herr_t H5SM__cache_table_get_load_size(const void *udata, size_t *image_len);
+static void *H5SM__cache_table_deserialize(const void *image, size_t len,
+    void *udata, hbool_t *dirty); 
+static herr_t H5SM__cache_table_image_len(const void *thing, size_t *image_len,
+    hbool_t *compressed_ptr, size_t *compressed_image_len_ptr);
+static herr_t H5SM__cache_table_serialize(const H5F_t *f, void *image,
+    size_t len, void *thing); 
+static herr_t H5SM__cache_table_free_icr(void *thing);
+
+static herr_t H5SM__cache_list_get_load_size(const void *udata, size_t *image_len);
+static void *H5SM__cache_list_deserialize(const void *image, size_t len,
+    void *udata, hbool_t *dirty); 
+static herr_t H5SM__cache_list_image_len(const void *thing, size_t *image_len,
+    hbool_t *compressed_ptr, size_t *compressed_image_len_ptr);
+static herr_t H5SM__cache_list_serialize(const H5F_t *f, void *image,
+    size_t len, void *thing);
+static herr_t H5SM__cache_list_free_icr(void *thing);
 
 
 /*********************/
@@ -82,23 +83,35 @@ static herr_t H5SM_list_size(const H5F_t *f, const H5SM_list_t H5_ATTR_UNUSED *l
 
 /* H5SM inherits cache-like properties from H5AC */
 const H5AC_class_t H5AC_SOHM_TABLE[1] = {{
-    H5AC_SOHM_TABLE_ID,
-    (H5AC_load_func_t)H5SM_table_load,
-    (H5AC_flush_func_t)H5SM_table_flush,
-    (H5AC_dest_func_t)H5SM_table_dest,
-    (H5AC_clear_func_t)H5SM_table_clear,
-    (H5AC_notify_func_t)NULL,
-    (H5AC_size_func_t)H5SM_table_size,
+    H5AC_SOHM_TABLE_ID,                 /* Metadata client ID */
+    "shared message table",             /* Metadata client name (for debugging) */
+    H5FD_MEM_SOHM_TABLE,                /* File space memory type for client */
+    H5AC__CLASS_NO_FLAGS_SET,           /* Client class behavior flags */
+    H5SM__cache_table_get_load_size,    /* 'get_load_size' callback */
+    H5SM__cache_table_deserialize,      /* 'deserialize' callback */
+    H5SM__cache_table_image_len,        /* 'image_len' callback */
+    NULL,                               /* 'pre_serialize' callback */
+    H5SM__cache_table_serialize,        /* 'serialize' callback */
+    NULL,                               /* 'notify' callback */
+    H5SM__cache_table_free_icr,         /* 'free_icr' callback */
+    NULL,			        /* 'clear' callback */
+    NULL,                               /* 'fsf_size' callback */
 }};
 
 const H5AC_class_t H5AC_SOHM_LIST[1] = {{
-    H5AC_SOHM_LIST_ID,
-    (H5AC_load_func_t)H5SM_list_load,
-    (H5AC_flush_func_t)H5SM_list_flush,
-    (H5AC_dest_func_t)H5SM_list_dest,
-    (H5AC_clear_func_t)H5SM_list_clear,
-    (H5AC_notify_func_t)NULL,
-    (H5AC_size_func_t)H5SM_list_size,
+    H5AC_SOHM_LIST_ID,                  /* Metadata client ID */
+    "shared message list",              /* Metadata client name (for debugging) */
+    H5FD_MEM_SOHM_TABLE,                /* File space memory type for client */
+    H5AC__CLASS_NO_FLAGS_SET,           /* Client class behavior flags */
+    H5SM__cache_list_get_load_size,     /* 'get_load_size' callback */
+    H5SM__cache_list_deserialize,       /* 'deserialize' callback */
+    H5SM__cache_list_image_len,         /* 'image_len' callback */
+    NULL,                               /* 'pre_serialize' callback */
+    H5SM__cache_list_serialize,         /* 'serialize' callback */
+    NULL,                               /* 'notify' callback */
+    H5SM__cache_list_free_icr,          /* 'free_icr' callback */
+    NULL,			        /* 'clear' callback */
+    NULL,                               /* 'fsf_size' callback */
 }};
 
 
@@ -114,32 +127,76 @@ const H5AC_class_t H5AC_SOHM_LIST[1] = {{
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5SM_table_load
+ * Function:    H5SM__cache_table_get_load_size()
+ *
+ * Purpose:	Return the size of the master table of Shared Object Header 
+ *		Message indexes on disk.  As this cache client doesn't use 
+ *		speculative reads, this value should be accurate.
+ *
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
+ *
+ * Programmer:  John Mainzer
+ *              7/28/14
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5SM__cache_table_get_load_size(const void *_udata, size_t *image_len)
+{
+    const H5SM_table_cache_ud_t *udata = (const H5SM_table_cache_ud_t *)_udata;     /* User data for callback */
+
+    FUNC_ENTER_STATIC_NOERR
+
+    /* Check arguments */
+    HDassert(udata);
+    HDassert(udata->f);
+    HDassert(image_len);
+
+    *image_len = H5SM_TABLE_SIZE(udata->f);
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5SM__cache_table_get_load_size() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5SM__cache_table_deserialize
  *
- * Purpose:	Loads the master table of Shared Object Header Message
- *              indexes.
+ * Purpose:	Given a buffer containing the on disk representation of the 
+ *		master table of Shared Object Header Message indexes, deserialize
+ *		the table, copy the contents into a newly allocated instance of 
+ *		H5SM_master_table_t, and return a pointer to the new instance.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Success:        Pointer to in core representation
+ *              Failure:        NULL
  *
- * Programmer:	James Laird
- *		November 6, 2006
+ * Programmer:  John Mainzer
+ *              7/28/14
  *
  *-------------------------------------------------------------------------
  */
-static H5SM_master_table_t *
-H5SM_table_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void H5_ATTR_UNUSED *udata)
+static void *
+H5SM__cache_table_deserialize(const void *_image, size_t len, void *_udata,
+    hbool_t H5_ATTR_UNUSED *dirty)
 {
-    H5SM_master_table_t *table = NULL;
-    H5WB_t        *wb = NULL;         /* Wrapped buffer for table data */
-    uint8_t       tbl_buf[H5SM_TBL_BUF_SIZE]; /* Buffer for table */
-    uint8_t       *buf;               /* Reading buffer */
-    const uint8_t *p;                 /* Pointer into input buffer */
-    uint32_t      stored_chksum;      /* Stored metadata checksum value */
-    uint32_t      computed_chksum;    /* Computed metadata checksum value */
-    size_t        u;                  /* Counter variable for index headers */
-    H5SM_master_table_t *ret_value;
-
-    FUNC_ENTER_NOAPI_NOINIT
+    H5F_t		   *f;                  /* File pointer -- from user data */
+    H5SM_master_table_t    *table = NULL;       /* Shared message table that we deserializing */
+    H5SM_table_cache_ud_t  *udata = (H5SM_table_cache_ud_t *)_udata;    /* Pointer to user data */
+    const uint8_t          *image = (const uint8_t *)_image;    /* Pointer into input buffer */
+    uint32_t                stored_chksum;      /* Stored metadata checksum value */
+    uint32_t                computed_chksum;    /* Computed metadata checksum value */
+    size_t                  u;                  /* Counter variable for index headers */
+    void *                  ret_value;          /* Return value */
+
+    FUNC_ENTER_STATIC
+
+    /* Check arguments */
+    HDassert(image);
+    HDassert(len > 0);
+    HDassert(udata);
+    HDassert(udata->f);
+    f = udata->f;
+    HDassert(dirty);
 
     /* Verify that we're reading version 0 of the table; this is the only
      * version defined so far.
@@ -152,35 +209,18 @@ H5SM_table_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void H5_ATTR_UNUSED *udat
 
     /* Read number of indexes and version from file superblock */
     table->num_indexes = H5F_SOHM_NINDEXES(f);
-
-    HDassert(addr == H5F_SOHM_ADDR(f));
-    HDassert(addr != HADDR_UNDEF);
     HDassert(table->num_indexes > 0);
 
-    /* Wrap the local buffer for serialized table info */
-    if(NULL == (wb = H5WB_wrap(tbl_buf, sizeof(tbl_buf))))
-        HGOTO_ERROR(H5E_SOHM, H5E_CANTINIT, NULL, "can't wrap buffer")
-
     /* Compute the size of the SOHM table header on disk.  This is the "table"
      * itself plus each index within the table
      */
     table->table_size = H5SM_TABLE_SIZE(f);
-
-    /* Get a pointer to a buffer that's large enough for serialized table */
-    if(NULL == (buf = (uint8_t *)H5WB_actual(wb, table->table_size)))
-        HGOTO_ERROR(H5E_SOHM, H5E_NOSPACE, NULL, "can't get actual buffer")
-
-    /* Read header from disk */
-    if(H5F_block_read(f, H5FD_MEM_SOHM_TABLE, addr, table->table_size, dxpl_id, buf) < 0)
-	HGOTO_ERROR(H5E_SOHM, H5E_READERROR, NULL, "can't read SOHM table")
-
-    /* Get temporary pointer to serialized table */
-    p = buf;
+    HDassert(table->table_size == len);
 
     /* Check magic number */
-    if(HDmemcmp(p, H5SM_TABLE_MAGIC, (size_t)H5_SIZEOF_MAGIC))
-	HGOTO_ERROR(H5E_SOHM, H5E_CANTLOAD, NULL, "bad SOHM table signature")
-    p += H5_SIZEOF_MAGIC;
+    if(HDmemcmp(image, H5SM_TABLE_MAGIC, (size_t)H5_SIZEOF_MAGIC))
+        HGOTO_ERROR(H5E_SOHM, H5E_CANTLOAD, NULL, "bad SOHM table signature")
+    image += H5_SIZEOF_MAGIC;
 
     /* Allocate space for the index headers in memory*/
     if(NULL == (table->indexes = (H5SM_index_header_t *)H5FL_ARR_MALLOC(H5SM_index_header_t, (size_t)table->num_indexes)))
@@ -189,45 +229,45 @@ H5SM_table_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void H5_ATTR_UNUSED *udat
     /* Read in the index headers */
     for(u = 0; u < table->num_indexes; ++u) {
         /* Verify correct version of index list */
-        if(H5SM_LIST_VERSION != *p++)
+        if(H5SM_LIST_VERSION != *image++) 
             HGOTO_ERROR(H5E_SOHM, H5E_VERSION, NULL, "bad shared message list version number")
 
         /* Type of the index (list or B-tree) */
-        table->indexes[u].index_type= (H5SM_index_type_t)*p++;
+        table->indexes[u].index_type= (H5SM_index_type_t)*image++;
 
         /* Type of messages in the index */
-        UINT16DECODE(p, table->indexes[u].mesg_types);
+        UINT16DECODE(image, table->indexes[u].mesg_types);
 
         /* Minimum size of message to share */
-        UINT32DECODE(p, table->indexes[u].min_mesg_size);
+        UINT32DECODE(image, table->indexes[u].min_mesg_size);
 
         /* List cutoff; fewer than this number and index becomes a list */
-        UINT16DECODE(p, table->indexes[u].list_max);
+        UINT16DECODE(image, table->indexes[u].list_max);
 
         /* B-tree cutoff; more than this number and index becomes a B-tree */
-        UINT16DECODE(p, table->indexes[u].btree_min);
+        UINT16DECODE(image, table->indexes[u].btree_min);
 
         /* Number of messages shared */
-        UINT16DECODE(p, table->indexes[u].num_messages);
+        UINT16DECODE(image, table->indexes[u].num_messages);
 
         /* Address of the actual index */
-        H5F_addr_decode(f, &p, &(table->indexes[u].index_addr));
+        H5F_addr_decode(f, &image, &(table->indexes[u].index_addr));
 
         /* Address of the index's heap */
-        H5F_addr_decode(f, &p, &(table->indexes[u].heap_addr));
+        H5F_addr_decode(f, &image, &(table->indexes[u].heap_addr));
 
         /* Compute the size of a list index for this SOHM index */
         table->indexes[u].list_size = H5SM_LIST_SIZE(f, table->indexes[u].list_max);
     } /* end for */
 
     /* Read in checksum */
-    UINT32DECODE(p, stored_chksum);
+    UINT32DECODE(image, stored_chksum);
 
     /* Sanity check */
-    HDassert((size_t)(p - (const uint8_t *)buf) == table->table_size);
+    HDassert((size_t)(image - (const uint8_t *)_image) == table->table_size);
 
     /* Compute checksum on entire header */
-    computed_chksum = H5_checksum_metadata(buf, (table->table_size - H5SM_SIZEOF_CHECKSUM), 0);
+    computed_chksum = H5_checksum_metadata(_image, (table->table_size - H5SM_SIZEOF_CHECKSUM), 0);
 
     /* Verify checksum */
     if(stored_chksum != computed_chksum)
@@ -237,147 +277,169 @@ H5SM_table_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void H5_ATTR_UNUSED *udat
     ret_value = table;
 
 done:
-    /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-        HDONE_ERROR(H5E_SOHM, H5E_CLOSEERROR, NULL, "can't close wrapped buffer")
     if(!ret_value && table)
         if(H5SM_table_free(table) < 0)
             HDONE_ERROR(H5E_SOHM, H5E_CANTFREE, NULL, "unable to destroy sohm table")
 
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5SM_table_load() */
+} /* end H5SM__cache_table_deserialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5SM_table_flush
+ * Function:    H5SM__cache_table_image_len
  *
- * Purpose:	Flushes (and destroys) the table of Shared Object Header
- *              Message indexes.
+ * Purpose:	Compute the size in bytes of the specified instance of
+ *		H5SM_master_table_t on disk, and return it in *image_len.
+ *		On failure, the value of *image_len is undefined.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
  *
- * Programmer:	James Laird
- *		November 6, 2006
+ * Programmer:  John Mainzer
+ *              7/28/14
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5SM_table_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5SM_master_table_t *table)
+H5SM__cache_table_image_len(const void *_thing, size_t *image_len,
+    hbool_t H5_ATTR_UNUSED *compressed_ptr, size_t H5_ATTR_UNUSED *compressed_image_len_ptr)
 {
-    H5WB_t *wb = NULL;                  /* Wrapped buffer for table data */
-    uint8_t tbl_buf[H5SM_TBL_BUF_SIZE]; /* Buffer for table */
-    herr_t ret_value = SUCCEED;  /* Return value */
+    const H5SM_master_table_t *table = (const H5SM_master_table_t *)_thing;     /* Shared message table to query */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC_NOERR
 
-    /* check arguments */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
+    /* Check arguments */
     HDassert(table);
+    HDassert(table->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(table->cache_info.type == H5AC_SOHM_TABLE);
+    HDassert(image_len);
 
-    if(table->cache_info.is_dirty) {
-        uint8_t  *buf;               /* Temporary buffer */
-        uint8_t  *p;                 /* Pointer into raw data buffer */
-        uint32_t computed_chksum;    /* Computed metadata checksum value */
-        size_t   u;                  /* Counter variable */
+    *image_len = table->table_size;
 
-        /* Verify that we're writing version 0 of the table; this is the only
-         * version defined so far.
-         */
-        HDassert(H5F_SOHM_VERS(f) == HDF5_SHAREDHEADER_VERSION);
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5SM__cache_table_image_len() */
 
-        /* Wrap the local buffer for serialized header info */
-        if(NULL == (wb = H5WB_wrap(tbl_buf, sizeof(tbl_buf))))
-            HGOTO_ERROR(H5E_SOHM, H5E_CANTINIT, FAIL, "can't wrap buffer")
+/***************************************/
+/* no H5SM_cache_table_pre_serialize() */
+/***************************************/
 
-        /* Get a pointer to a buffer that's large enough for serialized table */
-        if(NULL == (buf = (uint8_t *)H5WB_actual(wb, table->table_size)))
-            HGOTO_ERROR(H5E_SOHM, H5E_NOSPACE, FAIL, "can't get actual buffer")
+
+/*-------------------------------------------------------------------------
+ * Function:    H5SM__cache_table_serialize
+ *
+ * Purpose:	Serialize the contents of the supplied shared message table, and
+ *		load this data into the supplied buffer.
+ *
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
+ *
+ * Programmer:  John Mainzer
+ *              7/28/14
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5SM__cache_table_serialize(const H5F_t *f, void *_image, size_t len,
+    void *_thing)
+{
+    H5SM_master_table_t *table = (H5SM_master_table_t *)_thing; /* Shared message table to encode */
+    uint8_t            *image = (uint8_t *)_image;      /* Pointer into raw data buffer */
+    uint32_t            computed_chksum;    /* Computed metadata checksum value */
+    size_t              u;                  /* Counter variable */
 
-        /* Get temporary pointer to buffer for serialized table */
-        p = buf;
+    FUNC_ENTER_STATIC_NOERR
 
-        /* Encode magic number */
-        HDmemcpy(p, H5SM_TABLE_MAGIC, (size_t)H5_SIZEOF_MAGIC);
-        p += H5_SIZEOF_MAGIC;
+    /* Check arguments */
+    HDassert(f);
+    HDassert(image);
+    HDassert(table);
+    HDassert(table->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(table->cache_info.type == H5AC_SOHM_TABLE);
+    HDassert(table->table_size == len);
 
-        /* Encode each index header */
-        for(u = 0; u < table->num_indexes; ++u) {
-            /* Version for this list */
-            *p++ = H5SM_LIST_VERSION;
+    /* Verify that we're writing version 0 of the table; this is the only
+     * version defined so far.
+     */
+    HDassert(H5F_SOHM_VERS(f) == HDF5_SHAREDHEADER_VERSION);
 
-            /* Is message index a list or a B-tree? */
-            *p++ = table->indexes[u].index_type;
+    /* Encode magic number */
+    HDmemcpy(image, H5SM_TABLE_MAGIC, (size_t)H5_SIZEOF_MAGIC);
+    image += H5_SIZEOF_MAGIC;
 
-            /* Type of messages in the index */
-            UINT16ENCODE(p, table->indexes[u].mesg_types);
+    /* Encode each index header */
+   for(u = 0; u < table->num_indexes; ++u) {
+        /* Version for this list */
+        *image++ = H5SM_LIST_VERSION;
 
-            /* Minimum size of message to share */
-            UINT32ENCODE(p, table->indexes[u].min_mesg_size);
+        /* Is message index a list or a B-tree? */
+        *image++ = table->indexes[u].index_type;
 
-            /* List cutoff; fewer than this number and index becomes a list */
-            UINT16ENCODE(p, table->indexes[u].list_max);
+        /* Type of messages in the index */
+        UINT16ENCODE(image, table->indexes[u].mesg_types);
 
-            /* B-tree cutoff; more than this number and index becomes a B-tree */
-            UINT16ENCODE(p, table->indexes[u].btree_min);
+        /* Minimum size of message to share */
+        UINT32ENCODE(image, table->indexes[u].min_mesg_size);
 
-            /* Number of messages shared */
-            UINT16ENCODE(p, table->indexes[u].num_messages);
+        /* List cutoff; fewer than this number and index becomes a list */
+        UINT16ENCODE(image, table->indexes[u].list_max);
 
-            /* Address of the actual index */
-            H5F_addr_encode(f, &p, table->indexes[u].index_addr);
+        /* B-tree cutoff; more than this number and index becomes a B-tree */
+        UINT16ENCODE(image, table->indexes[u].btree_min);
 
-            /* Address of the index's heap */
-            H5F_addr_encode(f, &p, table->indexes[u].heap_addr);
-        } /* end for */
+        /* Number of messages shared */
+        UINT16ENCODE(image, table->indexes[u].num_messages);
 
-        /* Compute checksum on buffer */
-        computed_chksum = H5_checksum_metadata(buf, (table->table_size - H5SM_SIZEOF_CHECKSUM), 0);
-        UINT32ENCODE(p, computed_chksum);
+        /* Address of the actual index */
+        H5F_addr_encode(f, &image, table->indexes[u].index_addr);
 
-        /* Write the table to disk */
-        HDassert((size_t)(p - buf) == table->table_size);
-	if(H5F_block_write(f, H5FD_MEM_SOHM_TABLE, addr, table->table_size, dxpl_id, buf) < 0)
-	    HGOTO_ERROR(H5E_SOHM, H5E_CANTFLUSH, FAIL, "unable to save sohm table to disk")
+        /* Address of the index's heap */
+        H5F_addr_encode(f, &image, table->indexes[u].heap_addr);
+    } /* end for */
 
-	table->cache_info.is_dirty = FALSE;
-    } /* end if */
+    /* Compute checksum on buffer */
+    computed_chksum = H5_checksum_metadata(_image, (table->table_size - H5SM_SIZEOF_CHECKSUM), 0);
+    UINT32ENCODE(image, computed_chksum);
 
-    if(destroy)
-        if(H5SM_table_dest(f, table) < 0)
-	    HGOTO_ERROR(H5E_SOHM, H5E_CANTFREE, FAIL, "unable to destroy sohm table")
+    /* sanity check */
+    HDassert((size_t)(image - ((uint8_t *)_image)) == table->table_size);
 
-done:
-    /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-        HDONE_ERROR(H5E_SOHM, H5E_CLOSEERROR, FAIL, "can't close wrapped buffer")
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5SM__cache_table_serialize() */
 
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5SM_table_flush() */
+/*****************************************/
+/* no H5SM_cache_table_notify() function */
+/*****************************************/
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5SM_table_dest
+ * Function:    H5SM__cache_table_free_icr
  *
- * Purpose:	Frees memory used by the SOHM table.
+ * Purpose:	Free memory used by the SOHM table.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Note:	The metadata cache sets the object's cache_info.magic to
+ *		H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC before calling a free_icr
+ *		callback (checked in assert).
  *
- * Programmer:	James Laird
- *		November 6, 2006
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
+ *
+ * Programmer:  John Mainzer
+ *              7/28/14
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5SM_table_dest(H5F_t H5_ATTR_UNUSED *f, H5SM_master_table_t* table)
+H5SM__cache_table_free_icr(void *_thing)
 {
-    herr_t ret_value = SUCCEED;         /* Return value */
+    H5SM_master_table_t *table = (H5SM_master_table_t *)_thing;  /* Shared message table to release */
+    herr_t               ret_value = SUCCEED;    /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
     /* Check arguments */
     HDassert(table);
-    HDassert(table->indexes);
+    HDassert(table->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC);
+    HDassert(table->cache_info.type == H5AC_SOHM_TABLE);
 
     /* Destroy Shared Object Header Message table */
     if(H5SM_table_free(table) < 0)
@@ -385,105 +447,80 @@ H5SM_table_dest(H5F_t H5_ATTR_UNUSED *f, H5SM_master_table_t* table)
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5SM_table_dest() */
+} /* end H5SM_cache_table_free_icr() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5SM_table_clear
+ * Function:    H5SM__cache_list_get_load_size()
  *
- * Purpose:	Mark this table as no longer being dirty.
+ * Purpose:	Return the on disk size of list of SOHM messages.  In this case,
+ *		we simply look up the size in the user data, and return that value
+ *		in *image_len.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
  *
- * Programmer:	James Laird
- *		November 6, 2006
+ * Programmer:  John Mainzer
+ *              7/28/14
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5SM_table_clear(H5F_t *f, H5SM_master_table_t *table, hbool_t destroy)
+H5SM__cache_list_get_load_size(const void *_udata, size_t *image_len)
 {
-    herr_t ret_value = SUCCEED;         /* Return value */
-
-    FUNC_ENTER_NOAPI_NOINIT
-
-    /*
-     * Check arguments.
-     */
-    HDassert(table);
-
-    /* Reset the dirty flag.  */
-    table->cache_info.is_dirty = FALSE;
-
-    if(destroy)
-        if(H5SM_table_dest(f, table) < 0)
-	    HGOTO_ERROR(H5E_SOHM, H5E_CANTFREE, FAIL, "unable to delete SOHM master table")
-
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5SM_table_clear() */
+    const H5SM_list_cache_ud_t *udata = (const H5SM_list_cache_ud_t *)_udata;        /* User data for callback */
 
-
-/*-------------------------------------------------------------------------
- * Function:	H5SM_table_size
- *
- * Purpose:	Returns the size of the table encoded on disk.
- *
- * Return:	Non-negative on success/Negative on failure
- *
- * Programmer:	James Laird
- *		November 6, 2006
- *
- *-------------------------------------------------------------------------
- */
-static herr_t
-H5SM_table_size(const H5F_t H5_ATTR_UNUSED *f, const H5SM_master_table_t *table, size_t *size_ptr)
-{
-    FUNC_ENTER_NOAPI_NOINIT_NOERR
+    FUNC_ENTER_STATIC_NOERR
 
     /* Check arguments */
-    HDassert(f);
-    HDassert(table);
-    HDassert(size_ptr);
+    HDassert(udata);
+    HDassert(udata->header);
+    HDassert(udata->header->list_size > 0);
+    HDassert(image_len);
 
-    /* Set size value */
-    *size_ptr = table->table_size;
+    *image_len = udata->header->list_size;
 
     FUNC_LEAVE_NOAPI(SUCCEED)
-} /* end H5SM_table_size() */
+} /* end H5SM__cache_list_get_load_size() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5SM_list_load
+ * Function:    H5SM__cache_list_deserialize
  *
- * Purpose:	Loads a list of SOHM messages.
+ * Purpose:	Given a buffer containing the on disk image of a list of 
+ *		SOHM message, deserialize the list, load it into a newly allocated 
+ *		instance of H5SM_list_t, and return a pointer to same.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Success:        Pointer to in core representation
+ *              Failure:        NULL
  *
- * Programmer:	James Laird
- *		November 6, 2006
+ * Programmer:  John Mainzer
+ *              7/28/14
  *
  *-------------------------------------------------------------------------
  */
-static H5SM_list_t *
-H5SM_list_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
+static void *
+H5SM__cache_list_deserialize(const void *_image, size_t len, void *_udata,
+    hbool_t H5_ATTR_UNUSED *dirty)
 {
-    H5SM_list_t *list;          /* The SOHM list being read in */
-    H5SM_list_cache_ud_t *udata = (H5SM_list_cache_ud_t *)_udata; /* User data for callback */
-    H5SM_bt2_ctx_t ctx;         /* Message encoding context */
-    H5WB_t *wb = NULL;          /* Wrapped buffer for list index data */
-    uint8_t lst_buf[H5SM_LST_BUF_SIZE]; /* Buffer for list index */
-    uint8_t *buf;               /* Reading buffer */
-    uint8_t *p;                 /* Pointer into input buffer */
-    uint32_t stored_chksum;     /* Stored metadata checksum value */
-    uint32_t computed_chksum;   /* Computed metadata checksum value */
-    size_t u;                   /* Counter variable for messages in list */
-    H5SM_list_t *ret_value;     /* Return value */
+    H5SM_list_t          *list = NULL;     /* The SOHM list being read in */
+    H5SM_list_cache_ud_t *udata = (H5SM_list_cache_ud_t *)_udata;    /* User data for callback */
+    H5SM_bt2_ctx_t        ctx;             /* Message encoding context */
+    const uint8_t        *image = (const uint8_t *)_image;      /* Pointer into input buffer */
+    uint32_t              stored_chksum;   /* Stored metadata checksum value */
+    uint32_t              computed_chksum; /* Computed metadata checksum value */
+    size_t                u;               /* Counter variable for messages in list */
+    void *                ret_value;       /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
     /* Check arguments */
+    HDassert(image);
+    HDassert(len > 0);
+    HDassert(udata);
     HDassert(udata->header);
+    HDassert(udata->header->list_size == len);
+    HDassert(dirty);
 
     /* Allocate space for the SOHM list data structure */
     if(NULL == (list = H5FL_MALLOC(H5SM_list_t)))
@@ -495,42 +532,28 @@ H5SM_list_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
         HGOTO_ERROR(H5E_SOHM, H5E_NOSPACE, NULL, "file allocation failed for SOHM list")
     list->header = udata->header;
 
-    /* Wrap the local buffer for serialized list index info */
-    if(NULL == (wb = H5WB_wrap(lst_buf, sizeof(lst_buf))))
-        HGOTO_ERROR(H5E_SOHM, H5E_CANTINIT, NULL, "can't wrap buffer")
-
-    /* Get a pointer to a buffer that's large enough for serialized list index */
-    if(NULL == (buf = (uint8_t *)H5WB_actual(wb, udata->header->list_size)))
-        HGOTO_ERROR(H5E_SOHM, H5E_NOSPACE, NULL, "can't get actual buffer")
-
-    /* Read list from disk */
-    if(H5F_block_read(f, H5FD_MEM_SOHM_INDEX, addr, udata->header->list_size, dxpl_id, buf) < 0)
-	HGOTO_ERROR(H5E_SOHM, H5E_READERROR, NULL, "can't read SOHM list")
-
-    /* Get temporary pointer to serialized list index */
-    p = buf;
-
     /* Check magic number */
-    if(HDmemcmp(p, H5SM_LIST_MAGIC, (size_t)H5_SIZEOF_MAGIC))
+    if(HDmemcmp(image, H5SM_LIST_MAGIC, (size_t)H5_SIZEOF_MAGIC))
         HGOTO_ERROR(H5E_SOHM, H5E_CANTLOAD, NULL, "bad SOHM list signature")
-    p += H5_SIZEOF_MAGIC;
+    image += H5_SIZEOF_MAGIC;
 
     /* Read messages into the list array */
     ctx.sizeof_addr = H5F_SIZEOF_ADDR(udata->f);
     for(u = 0; u < udata->header->num_messages; u++) {
-        if(H5SM_message_decode(p, &(list->messages[u]), &ctx) < 0)
+        if(H5SM_message_decode(image, &(list->messages[u]), &ctx) < 0)
             HGOTO_ERROR(H5E_SOHM, H5E_CANTLOAD, NULL, "can't decode shared message")
-        p += H5SM_SOHM_ENTRY_SIZE(udata->f);
+
+        image += H5SM_SOHM_ENTRY_SIZE(udata->f);
     } /* end for */
 
     /* Read in checksum */
-    UINT32DECODE(p, stored_chksum);
+    UINT32DECODE(image, stored_chksum);
 
     /* Sanity check */
-    HDassert((size_t)(p - buf) <= udata->header->list_size);
+    HDassert((size_t)(image - (const uint8_t *)_image) <= udata->header->list_size);
 
     /* Compute checksum on entire header */
-    computed_chksum = H5_checksum_metadata(buf, ((size_t)(p - buf) - H5SM_SIZEOF_CHECKSUM), 0);
+    computed_chksum = H5_checksum_metadata(_image, ((size_t)(image - (const uint8_t *)_image) - H5SM_SIZEOF_CHECKSUM), 0);
 
     /* Verify checksum */
     if(stored_chksum != computed_chksum)
@@ -544,9 +567,6 @@ H5SM_list_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_udata)
     ret_value = list;
 
 done:
-    /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-        HDONE_ERROR(H5E_SOHM, H5E_CLOSEERROR, NULL, "can't close wrapped buffer")
     if(!ret_value && list) {
         if(list->messages)
             list->messages = H5FL_ARR_FREE(H5SM_sohm_t, list->messages);
@@ -554,205 +574,158 @@ done:
     } /* end if */
 
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5SM_list_load() */
+} /* end H5SM__cache_list_deserialize() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5SM_list_flush
+ * Function:    H5SM__cache_list_image_len
  *
- * Purpose:	Flush this list index.
+ * Purpose:	Get the size of the shared message list on disk.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
  *
- * Programmer:	James Laird
- *		November 6, 2006
+ * Programmer:  John Mainzer
+ *              7/28/14
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5SM_list_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5SM_list_t *list)
+H5SM__cache_list_image_len(const void *_thing, size_t *image_len,
+    hbool_t H5_ATTR_UNUSED *compressed_ptr, size_t H5_ATTR_UNUSED *compressed_image_len_ptr)
 {
-    H5WB_t *wb = NULL;                  /* Wrapped buffer for list index data */
-    uint8_t lst_buf[H5SM_LST_BUF_SIZE]; /* Buffer for list index */
-    herr_t ret_value = SUCCEED;         /* Return value */
+    const H5SM_list_t *list = (const H5SM_list_t *)_thing;      /* Shared message list to query */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC_NOERR
 
-    /* check arguments */
-    HDassert(f);
-    HDassert(H5F_addr_defined(addr));
+    /* Check arguments */
     HDassert(list);
+    HDassert(list->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(list->cache_info.type == H5AC_SOHM_LIST);
     HDassert(list->header);
+    HDassert(image_len);
 
-    if(list->cache_info.is_dirty) {
-        H5SM_bt2_ctx_t ctx;         /* Message encoding context */
-        uint8_t *buf;               /* Temporary buffer */
-        uint8_t *p;                 /* Pointer into raw data buffer */
-        uint32_t computed_chksum;   /* Computed metadata checksum value */
-        size_t mesgs_written;       /* Number of messages written to list */
-        size_t u;                   /* Local index variable */
-
-        /* Wrap the local buffer for serialized list index info */
-        if(NULL == (wb = H5WB_wrap(lst_buf, sizeof(lst_buf))))
-            HGOTO_ERROR(H5E_SOHM, H5E_CANTINIT, FAIL, "can't wrap buffer")
-
-        /* Get a pointer to a buffer that's large enough for serialized list index */
-        if(NULL == (buf = (uint8_t *)H5WB_actual(wb, list->header->list_size)))
-            HGOTO_ERROR(H5E_SOHM, H5E_NOSPACE, FAIL, "can't get actual buffer")
-
-        /* Get temporary pointer to buffer for serialized list index */
-        p = buf;
-
-        /* Encode magic number */
-        HDmemcpy(p, H5SM_LIST_MAGIC, (size_t)H5_SIZEOF_MAGIC);
-        p += H5_SIZEOF_MAGIC;
-
-        /* Write messages from the messages array to disk */
-        mesgs_written = 0;
-        ctx.sizeof_addr = H5F_SIZEOF_ADDR(f);
-        for(u = 0; u < list->header->list_max && mesgs_written < list->header->num_messages; u++) {
-            if(list->messages[u].location != H5SM_NO_LOC) {
-                if(H5SM_message_encode(p, &(list->messages[u]), &ctx) < 0)
-                    HGOTO_ERROR(H5E_SOHM, H5E_CANTFLUSH, FAIL, "unable to write shared message to disk")
-
-                p += H5SM_SOHM_ENTRY_SIZE(f);
-                ++mesgs_written;
-            } /* end if */
-        } /* end for */
-        HDassert(mesgs_written == list->header->num_messages);
-
-        /* Compute checksum on buffer */
-        computed_chksum = H5_checksum_metadata(buf, (size_t)(p - buf), 0);
-        UINT32ENCODE(p, computed_chksum);
-#ifdef H5_CLEAR_MEMORY
-HDmemset(p, 0, (list->header->list_size - (size_t)(p - buf)));
-#endif /* H5_CLEAR_MEMORY */
+    *image_len = list->header->list_size;
 
-        /* Write the list to disk */
-        HDassert((size_t)(p - buf) <= list->header->list_size);
-	if(H5F_block_write(f, H5FD_MEM_SOHM_INDEX, addr, list->header->list_size, dxpl_id, buf) < 0)
-	    HGOTO_ERROR(H5E_SOHM, H5E_CANTFLUSH, FAIL, "unable to save sohm table to disk")
-
-        list->cache_info.is_dirty = FALSE;
-    } /* end if */
-
-    if(destroy)
-        if(H5SM_list_dest(f, list) < 0)
-	    HGOTO_ERROR(H5E_SOHM, H5E_CANTFREE, FAIL, "unable to destroy list")
-
-done:
-    /* Release resources */
-    if(wb && H5WB_unwrap(wb) < 0)
-        HDONE_ERROR(H5E_SOHM, H5E_CLOSEERROR, FAIL, "can't close wrapped buffer")
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5SM__cache_list_image_len() */
 
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5SM_list_flush() */
+/**************************************/
+/* no H5SM_cache_list_pre_serialize() */
+/**************************************/
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5SM_list_dest
+ * Function:    H5SM__cache_list_serialize
  *
- * Purpose:	Frees all memory used by the list.
+ * Purpose:	Serialize the contents of the supplied shared message list, and
+ *		load this data into the supplied buffer.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
  *
- * Programmer:	James Laird
- *		November 6, 2006
+ * Programmer:  John Mainzer
+ *              7/28/14
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5SM_list_dest(H5F_t *f, H5SM_list_t* list)
+H5SM__cache_list_serialize(const H5F_t *f, void *_image, size_t len,
+    void *_thing)
 {
-    herr_t ret_value = SUCCEED;         /* Return value */
+    H5SM_list_t *list = (H5SM_list_t *)_thing ;   /* Instance being serialized */
+    H5SM_bt2_ctx_t ctx;         /* Message encoding context */
+    uint8_t *image = (uint8_t *)_image;         /* Pointer into raw data buffer */
+    uint32_t computed_chksum;   /* Computed metadata checksum value */
+    size_t mesgs_serialized;    /* Number of messages serialized */
+    size_t u;                   /* Local index variable */
+    herr_t       ret_value = SUCCEED;    /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
-    /* Sanity check */
+    /* Check arguments */
+    HDassert(f);
+    HDassert(image);
     HDassert(list);
+    HDassert(list->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(list->cache_info.type == H5AC_SOHM_LIST);
     HDassert(list->header);
-    HDassert(list->messages);
+    HDassert(list->header->list_size == len);
+
+    /* Encode magic number */
+    HDmemcpy(image, H5SM_LIST_MAGIC, (size_t)H5_SIZEOF_MAGIC);
+    image += H5_SIZEOF_MAGIC;
+
+    /* serialize messages from the messages array */
+    mesgs_serialized = 0;
+    ctx.sizeof_addr = H5F_SIZEOF_ADDR(f);
+    for(u = 0; ((u < list->header->list_max) && (mesgs_serialized < list->header->num_messages)); u++) {
+        if(list->messages[u].location != H5SM_NO_LOC) {
+            if(H5SM_message_encode(image, &(list->messages[u]), &ctx) < 0)
+                HGOTO_ERROR(H5E_SOHM, H5E_CANTFLUSH, FAIL, "unable to serialize shared message")
+
+            image += H5SM_SOHM_ENTRY_SIZE(f);
+            ++mesgs_serialized;
+        } /* end if */
+    } /* end for */
 
-    /* If we're going to free the space on disk, the address must be valid */
-    HDassert(!list->cache_info.free_file_space_on_destroy || H5F_addr_defined(list->cache_info.addr));
+    HDassert(mesgs_serialized == list->header->num_messages);
 
-    /* Check for freeing file space for shared message index list */
-    if(list->cache_info.free_file_space_on_destroy) {
-        /* Release the space on disk */
-        /* (XXX: Nasty usage of internal DXPL value! -QAK) */
-        if(H5MF_xfree(f, H5FD_MEM_SOHM_INDEX, H5AC_dxpl_id, list->cache_info.addr, (hsize_t)list->header->list_size) < 0)
-            HGOTO_ERROR(H5E_SOHM, H5E_NOSPACE, FAIL, "unable to free shared message list")
-    } /* end if */
+    /* Compute checksum on buffer */
+    computed_chksum = H5_checksum_metadata(_image, (size_t)(image - (uint8_t *)_image), 0);
+    UINT32ENCODE(image, computed_chksum);
 
-    /* Destroy Shared Object Header Message list */
-    if(H5SM_list_free(list) < 0)
-        HGOTO_ERROR(H5E_SOHM, H5E_CANTRELEASE, FAIL, "unable to free shared message list")
+    /* sanity check */
+    HDassert((size_t)(image - (uint8_t *)_image) <= list->header->list_size);
+
+#ifdef H5_CLEAR_MEMORY
+    HDmemset(image, 0, (list->header->list_size - (size_t)(image - (uint8_t *)_image)));
+#endif /* H5_CLEAR_MEMORY */
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5SM_list_dest() */
+} /* end H5SM__cache_list_serialize() */
+
+/****************************************/
+/* no H5SM_cache_list_notify() function */
+/****************************************/
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5SM_list_clear
+ * Function:    H5SM__cache_list_free_icr
  *
- * Purpose:	Marks a list as not dirty.
+ * Purpose:	Free all memory used by the list.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Note:	The metadata cache sets the object's cache_info.magic to
+ *		H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC before calling a free_icr
+ *		callback (checked in assert).
  *
- * Programmer:	James Laird
- *		November 6, 2006
+ * Return:      Success:        SUCCEED
+ *              Failure:        FAIL
+ *
+ * Programmer:  John Mainzer
+ *              7/28/14
  *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5SM_list_clear(H5F_t *f, H5SM_list_t *list, hbool_t destroy)
+H5SM__cache_list_free_icr(void *_thing)
 {
-    herr_t ret_value = SUCCEED;         /* Return value */
+    H5SM_list_t *list = (H5SM_list_t *)_thing;  /* Shared message list to release */
+    herr_t       ret_value = SUCCEED;    /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT
+    FUNC_ENTER_STATIC
 
     /* Check arguments */
     HDassert(list);
+    HDassert(list->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC);
+    HDassert(list->cache_info.type == H5AC_SOHM_LIST);
 
-    /* Reset the dirty flag.  */
-    list->cache_info.is_dirty = FALSE;
-
-    if(destroy)
-        if(H5SM_list_dest(f, list) < 0)
-	    HGOTO_ERROR(H5E_SOHM, H5E_CANTFREE, FAIL, "unable to destroy SOHM list")
+    /* Destroy Shared Object Header Message list */
+    if(H5SM_list_free(list) < 0)
+        HGOTO_ERROR(H5E_SOHM, H5E_CANTRELEASE, FAIL, "unable to free shared message list")
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end of H5SM_list_clear() */
-
-
-/*-------------------------------------------------------------------------
- * Function:	H5SM_list_size
- *
- * Purpose:	Gets the size of a list on disk.
- *
- * Return:	Non-negative on success/Negative on failure
- *
- * Programmer:	James Laird
- *		November 6, 2006
- *
- *-------------------------------------------------------------------------
- */
-static herr_t
-H5SM_list_size(const H5F_t H5_ATTR_UNUSED *f, const H5SM_list_t *list, size_t *size_ptr)
-{
-    FUNC_ENTER_NOAPI_NOINIT_NOERR
-
-    /* check arguments */
-    HDassert(f);
-    HDassert(list);
-    HDassert(list->header);
-    HDassert(size_ptr);
-
-    /* Set size value */
-    *size_ptr = list->header->list_size;
-
-    FUNC_LEAVE_NOAPI(SUCCEED)
-} /* end H5SM_list_size() */
+} /* end H5O_cache_list_free_icr() */
 
diff --git a/src/H5SMtest.c b/src/H5SMtest.c
index 12ed766..c4e02bc 100644
--- a/src/H5SMtest.c
+++ b/src/H5SMtest.c
@@ -98,7 +98,7 @@ H5SM_get_mesg_count_test(H5F_t *f, hid_t dxpl_id, unsigned type_id,
         cache_udata.f = f;
 
         /* Look up the master SOHM table */
-        if(NULL == (table = (H5SM_master_table_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_TABLE, H5F_SOHM_ADDR(f), &cache_udata, H5AC_READ)))
+        if(NULL == (table = (H5SM_master_table_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_TABLE, H5F_SOHM_ADDR(f), &cache_udata, H5AC__READ_ONLY_FLAG)))
             HGOTO_ERROR(H5E_SOHM, H5E_CANTPROTECT, FAIL, "unable to load SOHM master table")
 
         /* Find the correct index for this message type */
diff --git a/src/H5VMprivate.h b/src/H5VMprivate.h
index 33f2b28..bf4e3ca 100644
--- a/src/H5VMprivate.h
+++ b/src/H5VMprivate.h
@@ -125,7 +125,7 @@ H5_DLL ssize_t H5VM_memcpyvv(void *_dst,
  *
  *-------------------------------------------------------------------------
  */
-static H5_inline hsize_t H5_ATTR_UNUSED
+static H5_INLINE hsize_t H5_ATTR_UNUSED
 H5VM_vector_reduce_product(unsigned n, const hsize_t *v)
 {
     hsize_t                  ret_value = 1;
@@ -157,7 +157,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-static H5_inline htri_t H5_ATTR_UNUSED
+static H5_INLINE htri_t H5_ATTR_UNUSED
 H5VM_vector_zerop_u(int n, const hsize_t *v)
 {
     htri_t      ret_value=TRUE;       /* Return value */
@@ -192,7 +192,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-static H5_inline htri_t H5_ATTR_UNUSED
+static H5_INLINE htri_t H5_ATTR_UNUSED
 H5VM_vector_zerop_s(int n, const hssize_t *v)
 {
     htri_t      ret_value=TRUE;       /* Return value */
@@ -229,7 +229,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-static H5_inline int H5_ATTR_UNUSED
+static H5_INLINE int H5_ATTR_UNUSED
 H5VM_vector_cmp_u (unsigned n, const hsize_t *v1, const hsize_t *v2)
 {
     int ret_value=0;    /* Return value */
@@ -271,7 +271,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-static H5_inline int H5_ATTR_UNUSED
+static H5_INLINE int H5_ATTR_UNUSED
 H5VM_vector_cmp_s (unsigned n, const hssize_t *v1, const hssize_t *v2)
 {
     int ret_value=0;    /* Return value */
@@ -308,7 +308,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-static H5_inline void H5_ATTR_UNUSED
+static H5_INLINE void H5_ATTR_UNUSED
 H5VM_vector_inc(int n, hsize_t *v1, const hsize_t *v2)
 {
     while (n--) *v1++ += *v2++;
@@ -355,7 +355,7 @@ static const unsigned char LogTable256[] =
  *
  *-------------------------------------------------------------------------
  */
-static H5_inline unsigned H5_ATTR_UNUSED
+static H5_INLINE unsigned H5_ATTR_UNUSED
 H5VM_log2_gen(uint64_t n)
 {
     unsigned r;                         /* r will be log2(n) */
@@ -403,7 +403,7 @@ static const unsigned MultiplyDeBruijnBitPosition[32] =
  *
  *-------------------------------------------------------------------------
  */
-static H5_inline unsigned H5_ATTR_UNUSED
+static H5_INLINE unsigned H5_ATTR_UNUSED
 H5VM_log2_of2(uint32_t n)
 {
 #ifndef NDEBUG
@@ -424,7 +424,7 @@ H5VM_log2_of2(uint32_t n)
  *
  *-------------------------------------------------------------------------
  */
-static H5_inline hsize_t H5_ATTR_UNUSED
+static H5_INLINE hsize_t H5_ATTR_UNUSED
 H5VM_power2up(hsize_t n)
 {
     hsize_t     ret_value = 1;  /* Return value */
@@ -449,7 +449,7 @@ H5VM_power2up(hsize_t n)
  *
  *-------------------------------------------------------------------------
  */
-static H5_inline unsigned H5_ATTR_UNUSED
+static H5_INLINE unsigned H5_ATTR_UNUSED
 H5VM_limit_enc_size(uint64_t limit)
 {
     return (H5VM_log2_gen(limit) / 8) + 1;
@@ -478,7 +478,7 @@ static const unsigned char H5VM_bit_clear_g[8] = {0x7F, 0xBF, 0xDF, 0xEF, 0xF7,
  *
  *-------------------------------------------------------------------------
  */
-static H5_inline hbool_t H5_ATTR_UNUSED
+static H5_INLINE hbool_t H5_ATTR_UNUSED
 H5VM_bit_get(const unsigned char *buf, size_t offset)
 {
     /* Test the appropriate bit in the buffer */
@@ -505,7 +505,7 @@ H5VM_bit_get(const unsigned char *buf, size_t offset)
  *
  *-------------------------------------------------------------------------
  */
-static H5_inline void H5_ATTR_UNUSED
+static H5_INLINE void H5_ATTR_UNUSED
 H5VM_bit_set(unsigned char *buf, size_t offset, hbool_t val)
 {
     /* Set/reset the appropriate bit in the buffer */
diff --git a/src/H5config.h.in b/src/H5config.h.in
index 02dc75d..dfc4f44 100644
--- a/src/H5config.h.in
+++ b/src/H5config.h.in
@@ -172,6 +172,9 @@
 /* Define to 1 if you have the `get_fpc_csr' function. */
 #undef HAVE_GET_FPC_CSR
 
+/* Define if the compiler understands inline */
+#undef HAVE_INLINE
+
 /* Define if library will contain instrumentation to detect correct
    optimization operation */
 #undef HAVE_INSTRUMENTED_LIBRARY
@@ -398,6 +401,12 @@
 /* Define to 1 if you have the `_scrsize' function. */
 #undef HAVE__SCRSIZE
 
+/* Define if the compiler understands __inline */
+#undef HAVE___INLINE
+
+/* Define if the compiler understands __inline__ */
+#undef HAVE___INLINE__
+
 /* Define if HDF5's high-level library headers should be included in hdf5.h */
 #undef INCLUDE_HL
 
@@ -623,12 +632,6 @@
 /* Define to empty if `const' does not conform to ANSI C. */
 #undef const
 
-/* Define to `__inline__' or `__inline' if that's what the C compiler
-   calls it, or to nothing if 'inline' is not supported under any name.  */
-#ifndef __cplusplus
-#undef inline
-#endif
-
 /* Define to `long int' if <sys/types.h> does not define. */
 #undef off_t
 
diff --git a/src/H5private.h b/src/H5private.h
index f7a4171..9efd145 100644
--- a/src/H5private.h
+++ b/src/H5private.h
@@ -183,11 +183,22 @@
 
 #endif /*H5_HAVE_WIN32_API*/
 
-/* H5_inline */
-#ifndef H5_inline
-#define H5_inline
-#endif /* H5_inline */
-
+/* Various ways that inline functions can be declared */
+#if defined(H5_HAVE___INLINE__)
+    /* GNU (alternative form) */
+    #define H5_INLINE __inline__
+#elif defined(H5_HAVE___INLINE)
+    /* Visual Studio */
+    #define H5_INLINE __inline
+#elif defined(H5_HAVE_INLINE)
+    /* GNU, C++
+     * Use "inline" as a last resort on the off-chance that there will
+     * be C++ problems.
+     */
+    #define H5_INLINE inline
+#else
+    #define H5_INLINE
+#endif /* inline choices */
 
 #ifndef F_OK
 #   define F_OK  00
diff --git a/src/H5public.h b/src/H5public.h
index e625367..6cec869 100644
--- a/src/H5public.h
+++ b/src/H5public.h
@@ -94,10 +94,10 @@ extern "C" {
 /* Version numbers */
 #define H5_VERS_MAJOR	1	/* For major interface/format changes  	     */
 #define H5_VERS_MINOR	9	/* For minor interface/format changes  	     */
-#define H5_VERS_RELEASE	222	/* For tweaks, bug-fixes, or development     */
+#define H5_VERS_RELEASE	223	/* For tweaks, bug-fixes, or development     */
 #define H5_VERS_SUBRELEASE ""	/* For pre-releases like snap0       */
 				/* Empty string for real releases.           */
-#define H5_VERS_INFO    "HDF5 library version: 1.9.222"      /* Full version string */
+#define H5_VERS_INFO    "HDF5 library version: 1.9.223"      /* Full version string */
 
 #define H5check()	H5check_version(H5_VERS_MAJOR,H5_VERS_MINOR,	      \
 				        H5_VERS_RELEASE)
diff --git a/src/Makefile.am b/src/Makefile.am
index 2df095e..b6c4dad 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -42,9 +42,11 @@ DISTCLEANFILES=H5pubconf.h
 # library sources
 libhdf5_la_SOURCES= H5.c H5checksum.c H5dbg.c H5system.c H5timer.c H5trace.c \
         H5A.c H5Abtree2.c H5Adense.c H5Adeprec.c H5Aint.c H5Atest.c \
-        H5AC.c H5B.c H5Bcache.c H5Bdbg.c \
+        H5AC.c H5ACmpio.c \
+        H5B.c H5Bcache.c H5Bdbg.c \
         H5B2.c H5B2cache.c H5B2dbg.c H5B2hdr.c H5B2int.c H5B2stat.c H5B2test.c \
-        H5C.c H5CS.c \
+        H5C.c H5Cmpio.c \
+        H5CS.c \
         H5D.c H5Dbtree.c H5Dchunk.c H5Dcompact.c H5Dcontig.c H5Ddbg.c \
         H5Ddeprec.c H5Defl.c H5Dfill.c H5Dint.c \
         H5Dio.c H5Dlayout.c \
diff --git a/src/Makefile.in b/src/Makefile.in
index ffa6fa9..4459f6f 100644
--- a/src/Makefile.in
+++ b/src/Makefile.in
@@ -150,9 +150,9 @@ LTLIBRARIES = $(lib_LTLIBRARIES)
 libhdf5_la_LIBADD =
 am_libhdf5_la_OBJECTS = H5.lo H5checksum.lo H5dbg.lo H5system.lo \
 	H5timer.lo H5trace.lo H5A.lo H5Abtree2.lo H5Adense.lo \
-	H5Adeprec.lo H5Aint.lo H5Atest.lo H5AC.lo H5B.lo H5Bcache.lo \
+	H5Adeprec.lo H5Aint.lo H5Atest.lo H5AC.lo H5ACmpio.lo H5B.lo H5Bcache.lo \
 	H5Bdbg.lo H5B2.lo H5B2cache.lo H5B2dbg.lo H5B2hdr.lo \
-	H5B2int.lo H5B2stat.lo H5B2test.lo H5C.lo H5CS.lo H5D.lo \
+	H5B2int.lo H5B2stat.lo H5B2test.lo H5C.lo H5Cmpio.lo H5CS.lo H5D.lo \
 	H5Dbtree.lo H5Dchunk.lo H5Dcompact.lo H5Dcontig.lo H5Ddbg.lo \
 	H5Ddeprec.lo H5Defl.lo H5Dfill.lo H5Dint.lo H5Dio.lo \
 	H5Dlayout.lo H5Dmpio.lo H5Doh.lo H5Dscatgath.lo H5Dselect.lo \
@@ -741,7 +741,7 @@ CHECK_CLEANFILES = *.chkexe *.chklog *.clog *.clog2
 # After making changes, run bin/reconfigure to update other configure related
 # files like Makefile.in.
 LT_VERS_INTERFACE = 6
-LT_VERS_REVISION = 212
+LT_VERS_REVISION = 213
 LT_VERS_AGE = 0
 
 # Our main target, the HDF5 library
@@ -758,9 +758,9 @@ DISTCLEANFILES = H5pubconf.h
 # library sources
 libhdf5_la_SOURCES = H5.c H5checksum.c H5dbg.c H5system.c H5timer.c H5trace.c \
         H5A.c H5Abtree2.c H5Adense.c H5Adeprec.c H5Aint.c H5Atest.c \
-        H5AC.c H5B.c H5Bcache.c H5Bdbg.c \
+        H5AC.c H5ACmpio.c H5B.c H5Bcache.c H5Bdbg.c \
         H5B2.c H5B2cache.c H5B2dbg.c H5B2hdr.c H5B2int.c H5B2stat.c H5B2test.c \
-        H5C.c H5CS.c \
+        H5C.c H5Cmpio.c H5CS.c \
         H5D.c H5Dbtree.c H5Dchunk.c H5Dcompact.c H5Dcontig.c H5Ddbg.c \
         H5Ddeprec.c H5Defl.c H5Dfill.c H5Dint.c \
         H5Dio.c H5Dlayout.c \
@@ -981,6 +981,7 @@ distclean-compile:
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5A.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5AC.Plo@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5ACmpio.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5Abtree2.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5Adense.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5Adeprec.Plo@am__quote@
@@ -997,6 +998,7 @@ distclean-compile:
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5Bcache.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5Bdbg.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5C.Plo@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5Cmpio.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5CS.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5D.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5Dbtree.Plo@am__quote@