[svn-r14064] Implemented function allowing the user to cork the metadata cache.

Also implemented associated test code.

6 files changed, 266 insertions, 59 deletions

diff --git a/src/H5AC.c b/src/H5AC.c
index 31f757f..3389dc6 100644
--- a/src/H5AC.c
+++ b/src/H5AC.c
@@ -2537,6 +2537,15 @@ done:
  *		JRM - 6/8/06
  *		Added support for the new trace file related fields.
  *
+ *		JRM - 7/28/07
+ *		Added support for the new evictions enabled related fields.
+ *		
+ *		Observe that H5AC_get_cache_auto_resize_config() and 
+ *		H5AC_set_cache_auto_resize_config() are becoming generic
+ *		metadata cache configuration routines as they gain 
+ *		switches for functions that are only tenuously related 
+ *		to auto resize configuration.
+ *
  *-------------------------------------------------------------------------
  */
 
@@ -2546,6 +2555,7 @@ H5AC_get_cache_auto_resize_config(H5AC_t * cache_ptr,
 {
     herr_t result;
     herr_t ret_value = SUCCEED;      /* Return value */
+    hbool_t evictions_enabled;
     H5C_auto_size_ctl_t internal_config;
 
     FUNC_ENTER_NOAPI(H5AC_get_cache_auto_resize_config, FAIL)
@@ -2581,6 +2591,14 @@ H5AC_get_cache_auto_resize_config(H5AC_t * cache_ptr,
                     "H5C_get_cache_auto_resize_config() failed.")
     }
 
+    result = H5C_get_evictions_enabled((H5C_t *)cache_ptr, &evictions_enabled);
+
+    if ( result < 0 ) {
+
+        HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, \
+		    "H5C_get_resize_enabled() failed.")
+    }
+
     if ( internal_config.rpt_fcn == NULL ) {
 
         config_ptr->rpt_fcn_enabled = FALSE;
@@ -2593,6 +2611,8 @@ H5AC_get_cache_auto_resize_config(H5AC_t * cache_ptr,
     config_ptr->open_trace_file        = FALSE;
     config_ptr->close_trace_file       = FALSE;
     config_ptr->trace_file_name[0]     = '\0';
+    config_ptr->set_evictions_enabled  = FALSE;
+    config_ptr->evictions_enabled      = evictions_enabled;
     config_ptr->set_initial_size       = internal_config.set_initial_size;
     config_ptr->initial_size           = internal_config.initial_size;
     config_ptr->min_clean_fraction     = internal_config.min_clean_fraction;
@@ -2788,6 +2808,15 @@ done:
  *		John Mainzer -- 6/7/06
  *		Added trace file support.
  *
+ *		John Mainzer -- 7/28/07
+ *		Added support for the new evictions enabled related fields.
+ *		
+ *		Observe that H5AC_get_cache_auto_resize_config() and 
+ *		H5AC_set_cache_auto_resize_config() are becoming generic
+ *		metadata cache configuration routines as they gain 
+ *		switches for functions that are only tenuously related 
+ *		to auto resize configuration.
+ *
  *-------------------------------------------------------------------------
  */
 
@@ -2835,56 +2864,11 @@ H5AC_set_cache_auto_resize_config(H5AC_t * cache_ptr,
         HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "bad cache_ptr on entry.")
     }
 
-    if ( config_ptr == NULL ) {
-
-        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "NULL config_ptr on entry.")
-    }
-
-    if ( config_ptr->version != H5AC__CURR_CACHE_CONFIG_VERSION ) {
-
-        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "Unknown config version.")
-    }
-
-    if ( ( config_ptr->rpt_fcn_enabled != TRUE ) &&
-         ( config_ptr->rpt_fcn_enabled != FALSE ) ) {
-
-        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, \
-                    "config_ptr->rpt_fcn_enabled must be either TRUE or FALSE.")
-    }
-
-    if ( ( config_ptr->open_trace_file != TRUE ) &&
-         ( config_ptr->open_trace_file != FALSE ) ) {
-
-        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, \
-                    "config_ptr->open_trace_file must be either TRUE or FALSE.")
-    }
-
-    if ( ( config_ptr->close_trace_file != TRUE ) &&
-         ( config_ptr->close_trace_file != FALSE ) ) {
-
-        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, \
-                  "config_ptr->close_trace_file must be either TRUE or FALSE.")
-    }
-
-    /* don't bother to test trace_file_name unless open_trace_file is TRUE */
-    if ( config_ptr->open_trace_file ) {
-
-        /* Can't really test the trace_file_name field without trying to
-         * open the file, so we will content ourselves with a couple of
-         * sanity checks on the length of the file name.
-         */
-        name_len = HDstrlen(config_ptr->trace_file_name);
-
-        if ( name_len <= 0 ) {
-
-            HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, \
-                        "config_ptr->trace_file_name is empty.")
+    result = H5AC_validate_config(config_ptr);
 
-        } else if ( name_len > H5AC__MAX_TRACE_FILE_NAME_LEN ) {
+    if ( result != SUCCEED ) {
 
-            HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, \
-                        "config_ptr->trace_file_name too long.")
-        }
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "Bad cache configuration");
     }
 
     if ( config_ptr->open_trace_file ) {
@@ -2957,6 +2941,18 @@ H5AC_set_cache_auto_resize_config(H5AC_t * cache_ptr,
                     "H5C_set_cache_auto_resize_config() failed.")
     }
 
+    if ( config_ptr->set_evictions_enabled ) {
+
+        result = H5C_set_evictions_enabled((H5C_t *)cache_ptr,
+			                   config_ptr->evictions_enabled);
+
+	if ( result < 0 ) {
+
+            HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, \
+                        "H5C_set_evictions_enabled() failed.")
+	}
+    }
+
 #ifdef H5_HAVE_PARALLEL
     if ( cache_ptr->aux_ptr != NULL ) {
 
@@ -2977,13 +2973,15 @@ done:
          ( trace_file_ptr != NULL ) ) {
 
 	HDfprintf(trace_file_ptr, 
-                  "%s %d %d %d %d \"%s\" %d %d %f %d %d %ld %d %f %f %d %d %d %f %f %d %d %d %d %f %d %d\n", 
+                  "%s %d %d %d %d \"%s\" %d %d %d %d %f %d %d %ld %d %f %f %d %d %d %f %f %d %d %d %d %f %d %d\n", 
 		  "H5AC_set_cache_auto_resize_config",
 		  trace_config.version,
 		  (int)(trace_config.rpt_fcn_enabled),
 		  (int)(trace_config.open_trace_file),
 		  (int)(trace_config.close_trace_file),
 		  trace_config.trace_file_name,
+		  (int)(trace_config.set_evictions_enabled),
+		  (int)(trace_config.evictions_enabled),
 		  (int)(trace_config.set_initial_size),
 		  (int)(trace_config.initial_size),
 		  trace_config.min_clean_fraction,
@@ -3041,6 +3039,13 @@ done:
  *              are applied.
  *              					JRM - 5/15/06
  *
+ *	      - Added code testing the evictions enabled field.  At 
+ *	        present this consists of verifying that if 
+ *	        set_evictions_enabled is TRUE and evictions_enabled
+ *	        is FALSE, then automatic cache resizing in disabled.
+ *
+ *	        					JRM - 7/28/07
+ *
  *-------------------------------------------------------------------------
  */
 
@@ -3107,6 +3112,29 @@ H5AC_validate_config(H5AC_cache_config_t * config_ptr)
 	}
     }
 
+    if ( ( config_ptr->set_evictions_enabled != TRUE ) &&
+         ( config_ptr->set_evictions_enabled != FALSE ) ) {
+
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, \
+            "config_ptr->set_evictions_enabled must be either TRUE or FALSE.")
+    }
+
+    if ( ( config_ptr->evictions_enabled != TRUE ) &&
+         ( config_ptr->evictions_enabled != FALSE ) ) {
+
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, \
+            "config_ptr->evictions_enabled must be either TRUE or FALSE.")
+    }
+
+    if ( ( config_ptr->set_evictions_enabled == TRUE ) &&
+         ( config_ptr->evictions_enabled == FALSE ) &&
+	 ( ( config_ptr->incr_mode != H5C_incr__off ) || 
+	   ( config_ptr->incr_mode != H5C_decr__off ) ) ) {
+
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, \
+                    "Can't disable evictions while auto-resize is enabled.")
+    }
+
     if ( config_ptr->dirty_bytes_threshold < H5AC__MIN_DIRTY_BYTES_THRESHOLD ) {
 
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL,
diff --git a/src/H5ACprivate.h b/src/H5ACprivate.h
index 34ca4ef..0d10c88 100644
--- a/src/H5ACprivate.h
+++ b/src/H5ACprivate.h
@@ -201,6 +201,8 @@ extern hid_t H5AC_ind_dxpl_id;
   /* hbool_t     open_trace_file        = */ FALSE,                           \
   /* hbool_t     close_trace_file       = */ FALSE,                           \
   /* char        trace_file_name[]      = */ "",                              \
+  /* hbool_t     set_evictions_enabled  = */ FALSE,                           \
+  /* hbool_t     evictions_enabled      = */ TRUE,                            \
   /* hbool_t     set_initial_size       = */ TRUE,                            \
   /* size_t      initial_size           = */ ( 1 * 1024 * 1024),              \
   /* double      min_clean_fraction     = */ 0.5,                             \
diff --git a/src/H5ACpublic.h b/src/H5ACpublic.h
index 362b14f..76e5530 100644
--- a/src/H5ACpublic.h
+++ b/src/H5ACpublic.h
@@ -107,6 +107,30 @@ extern "C" {
  * 	The length of the path must not exceed H5AC__MAX_TRACE_FILE_NAME_LEN
  * 	characters.
  *
+ * set_evictions_enabled: Boolean flag indicating whether the cache
+ * 	evictions_enabled flag is to be set to the value specified
+ * 	in the evictions_enabled field below.
+ *
+ * evictions_enabled:  Boolean field used to either report the current
+ * 	evictions enabled status of the cache, or, when 
+ * 	set_evictions_enabled is TRUE, to set the cache's evictions
+ * 	enabled status.
+ *
+ * 	In general, the metadata cache should always be allowed to 
+ * 	evict entries.  However, in some cases it is advantageous to 
+ * 	disable evictions briefly, and thereby postpone metadata 
+ * 	writes.  However, this must be done with care, as the cache
+ * 	can grow quickly.  If you do this, re-enable evictions as
+ * 	soon as possible and monitor cache size.
+ *
+ * 	At present, evictions can only be disabled if automatic
+ * 	cache resizing is also disabled (that is, ( incr_mode ==
+ *	H5C_incr__off ) && ( decr_mode == H5C_decr__off )).  There
+ *	is no logical reason why this should be so, but it simplifies
+ *	implementation and testing, and I can't think of any reason
+ *	why it would be desireable.  If you can think of one, I'll
+ *	revisit the issue.
+ *
  * set_initial_size: Boolean flag indicating whether the size of the
  *      initial size of the cache is to be set to the value given in
  *      the initial_size field.  If set_initial_size is FALSE, the
@@ -160,6 +184,9 @@ extern "C" {
  *              at its maximum size, or if the cache is not already using
  *              all available space.
  *
+ *      Note that you must set decr_mode to H5C_incr__off if you 
+ *      disable metadata cache entry evictions.
+ *
  * lower_hr_threshold: Lower hit rate threshold.  If the increment mode
  *      (incr_mode) is H5C_incr__threshold and the hit rate drops below the
  *      value supplied in this field in an epoch, increment the cache size by
@@ -217,6 +244,9 @@ extern "C" {
  *              over the last epoch exceeds the value provided in the
  *              upper_hr_threshold field.
  *
+ *      Note that you must set decr_mode to H5C_decr__off if you 
+ *      disable metadata cache entry evictions.
+ *
  * upper_hr_threshold: Upper hit rate threshold.  The use of this field
  *      varies according to the current decr_mode:
  *
@@ -316,6 +346,9 @@ typedef struct H5AC_cache_config_t
     hbool_t                  close_trace_file;
     char                     trace_file_name[H5AC__MAX_TRACE_FILE_NAME_LEN + 1];
 
+    hbool_t                  set_evictions_enabled;
+    hbool_t                  evictions_enabled;
+
     hbool_t                  set_initial_size;
     size_t                   initial_size;
 
diff --git a/src/H5C.c b/src/H5C.c
index d9951fe..8ac9929 100644
--- a/src/H5C.c
+++ b/src/H5C.c
@@ -2835,6 +2835,10 @@ done:
  *		Added initialization for the new is_read_only and 
  *		ro_ref_count fields.
  *
+ *		JRM -- 7/27/07
+*		Added initialization for the new evictions_enabled 
+*		field of H5C_t.
+ *
  *-------------------------------------------------------------------------
  */
 
@@ -2906,6 +2910,8 @@ H5C_create(size_t		      max_cache_size,
 
     cache_ptr->log_flush			= log_flush;
 
+    cache_ptr->evictions_enabled		= TRUE;
+
     cache_ptr->index_len			= 0;
     cache_ptr->index_size			= (size_t)0;
 
@@ -4260,6 +4266,52 @@ done:
 
 
 /*-------------------------------------------------------------------------
+ * Function:    H5C_get_evictions_enabled()
+ *
+ * Purpose:	Copy the current value of cache_ptr->evictions_enabled into
+ * 		*evictions_enabled_ptr.
+ *
+ * Return:      SUCCEED on success, and FAIL on failure.
+ *
+ * Programmer:  John Mainzer
+ *		7/27/07
+ *
+ * Modifications:
+ *
+ *		None.
+ *
+ *-------------------------------------------------------------------------
+ */
+
+herr_t
+H5C_get_evictions_enabled(H5C_t * cache_ptr,
+                          hbool_t * evictions_enabled_ptr)
+{
+    herr_t ret_value = SUCCEED;      /* Return value */
+
+    FUNC_ENTER_NOAPI(H5C_get_evictions_enabled, FAIL)
+
+    if ( ( cache_ptr == NULL ) || ( cache_ptr->magic != H5C__H5C_T_MAGIC ) ) {
+
+        HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Bad cache_ptr on entry.")
+    }
+
+    if ( evictions_enabled_ptr == NULL ) {
+
+        HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, \
+		    "Bad evictions_enabled_ptr on entry.")
+    }
+
+    *evictions_enabled_ptr = cache_ptr->evictions_enabled;
+
+done:
+
+    FUNC_LEAVE_NOAPI(ret_value)
+
+} /* H5C_get_evictions_enabled() */
+
+
+/*-------------------------------------------------------------------------
  * Function:    H5C_get_trace_file_ptr
  *
  * Purpose:     Get the trace_file_ptr field from the cache.
@@ -4378,6 +4430,10 @@ done:
  *		Added initialization for the new is_read_only and 
  *		ro_ref_count fields.
  *
+ *		JRM -- 8/1/07
+ *		Added code to disable evictions when the new 
+ *		evictions_enabled field is FALSE.
+ *
  *-------------------------------------------------------------------------
  */
 
@@ -4468,7 +4524,9 @@ H5C_insert_entry(H5F_t * 	     f,
 
     H5C__RESET_CACHE_ENTRY_STATS(entry_ptr)
 
-    if ((cache_ptr->index_size + entry_ptr->size) > cache_ptr->max_cache_size) {
+    if ( ( cache_ptr->evictions_enabled ) &&
+         ( (cache_ptr->index_size + entry_ptr->size) > 
+	    cache_ptr->max_cache_size ) ) {
 
         size_t space_needed;
 
@@ -5545,6 +5603,10 @@ done:
  * 		Also added code to allow multiple read only protects
  * 		of cache entries.
  *
+ * 		JRM -- 7/27/07
+ * 		Added code supporting the new evictions_enabled fieled
+ * 		in H5C_t.
+ *
  *-------------------------------------------------------------------------
  */
 
@@ -5616,9 +5678,10 @@ H5C_protect(H5F_t *	        f,
 
         entry_ptr = (H5C_cache_entry_t *)thing;
 
-        /* try to free up some space if necessary */
-        if ( (cache_ptr->index_size + entry_ptr->size) >
-              cache_ptr->max_cache_size ) {
+        /* try to free up some space if necessary and if evictions are permitted */
+        if ( ( cache_ptr->evictions_enabled ) &&
+	     ( (cache_ptr->index_size + entry_ptr->size) > 
+	       cache_ptr->max_cache_size ) ) {
 
             size_t space_needed;
 
@@ -5754,10 +5817,11 @@ H5C_protect(H5F_t *	        f,
 
     ret_value = thing;
 
-    if ( ( cache_ptr->size_decreased ) ||
-         ( ( cache_ptr->resize_enabled ) &&
-           ( cache_ptr->cache_accesses >=
-             (cache_ptr->resize_ctl).epoch_length ) ) ) {
+    if ( ( cache_ptr->evictions_enabled ) &&
+	 ( ( cache_ptr->size_decreased ) ||
+           ( ( cache_ptr->resize_enabled ) &&
+             ( cache_ptr->cache_accesses >=
+               (cache_ptr->resize_ctl).epoch_length ) ) ) ) {
 
         if ( ! have_write_permitted ) {
 
@@ -6140,6 +6204,66 @@ done:
 
 
 /*-------------------------------------------------------------------------
+ * Function:    H5C_set_evictions_enabled()
+ *
+ * Purpose:	Set cache_ptr->evictions_enabled to the value of the 
+ * 		evictions enabled parameter.
+ *
+ * Return:      SUCCEED on success, and FAIL on failure.
+ *
+ * Programmer:  John Mainzer
+ *		7/27/07
+ *
+ * Modifications:
+ *
+ *		None.
+ *
+ *-------------------------------------------------------------------------
+ */
+
+herr_t
+H5C_set_evictions_enabled(H5C_t * cache_ptr,
+                          hbool_t evictions_enabled)
+{
+    herr_t ret_value = SUCCEED;      /* Return value */
+
+    FUNC_ENTER_NOAPI(H5C_set_evictions_enabled, FAIL)
+
+    if ( ( cache_ptr == NULL ) || ( cache_ptr->magic != H5C__H5C_T_MAGIC ) ) {
+
+        HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Bad cache_ptr on entry.")
+    }
+
+    if ( ( evictions_enabled != TRUE ) && ( evictions_enabled != FALSE ) ) {
+
+        HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, \
+		    "Bad evictions_enabled on entry.")
+    }
+
+    /* There is no fundamental reason why we should not permit 
+     * evictions to be disabled while automatic resize is enabled.
+     * However, I can't think of any good reason why one would 
+     * want to, and allowing it would greatly complicate testing
+     * the feature.  Hence the following:
+     */
+    if ( ( evictions_enabled != TRUE ) &&
+         ( ( cache_ptr->resize_ctl.incr_mode != H5C_incr__off ) ||
+	   ( cache_ptr->resize_ctl.decr_mode != H5C_decr__off ) ) ) {
+
+        HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, \
+		    "Can't disable evictions when auto resize enabled.")
+    }
+
+    cache_ptr->evictions_enabled = evictions_enabled;
+
+done:
+
+    FUNC_LEAVE_NOAPI(ret_value)
+
+} /* H5C_set_evictions_enabled() */
+
+
+/*-------------------------------------------------------------------------
  * Function:    H5C_set_prefix
  *
  * Purpose:     Set the values of the prefix field of H5C_t.  This
diff --git a/src/H5Cpkg.h b/src/H5Cpkg.h
index 3b8d650..949f923 100644
--- a/src/H5Cpkg.h
+++ b/src/H5Cpkg.h
@@ -176,6 +176,18 @@
  *		entry is flushed to disk.
  *
  *
+ * In cases where memory is plentiful, and performance is an issue, it
+ * is useful to disable all cache evictions, and thereby postpone metadata
+ * writes.  The following field is used to implement this.
+ *
+ * evictions_enabled:  Boolean flag that is initialized to TRUE.  When
+ * 		this flag is set to FALSE, the metadata cache will not 
+ * 		attempt to evict entries to make space for newly protected
+ * 		entries, and instead the will grow without limit.
+ * 		
+ * 		Needless to say, this feature must be used with care.
+ *
+ *
  * The cache requires an index to facilitate searching for entries.  The
  * following fields support that index.
  *
@@ -802,6 +814,8 @@ struct H5C_t
 
     H5C_log_flush_func_t	log_flush;
 
+    hbool_t			evictions_enabled;
+
     int32_t                     index_len;
     size_t                      index_size;
     H5C_cache_entry_t *		(index[H5C__HASH_TABLE_LEN]);
diff --git a/src/H5Cprivate.h b/src/H5Cprivate.h
index d3fcbeb..e169bd6 100644
--- a/src/H5Cprivate.h
+++ b/src/H5Cprivate.h
@@ -37,7 +37,7 @@
 #include "H5Fprivate.h"		/* File access				*/
 
 
-#define H5C_DO_SANITY_CHECKS		0
+#define H5C_DO_SANITY_CHECKS		1
 #define H5C_DO_EXTREME_SANITY_CHECKS	0
 
 /* This sanity checking constant was picked out of the air.  Increase
@@ -51,7 +51,7 @@
 /* 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
+#define H5C_COLLECT_CACHE_STATS	1
 
 /* H5C_COLLECT_CACHE_ENTRY_STATS controls collection of statistics
  * in individual cache entries.
@@ -901,6 +901,9 @@ H5_DLL herr_t H5C_get_entry_status(H5C_t *   cache_ptr,
                                    hbool_t * is_protected_ptr,
 				   hbool_t * is_pinned_ptr);
 
+H5_DLL herr_t H5C_get_evictions_enabled(H5C_t * cache_ptr,
+                                        hbool_t * evictions_enabled_ptr);
+
 H5_DLL herr_t H5C_get_trace_file_ptr(H5C_t * cache_ptr,
 		                     FILE ** trace_file_ptr_ptr);
 
@@ -955,6 +958,9 @@ H5_DLL herr_t H5C_resize_pinned_entry(H5C_t * cache_ptr,
 H5_DLL herr_t H5C_set_cache_auto_resize_config(H5C_t * cache_ptr,
                                                H5C_auto_size_ctl_t *config_ptr);
 
+H5_DLL herr_t H5C_set_evictions_enabled(H5C_t * cache_ptr,
+                                        hbool_t evictions_enabled);
+
 H5_DLL herr_t H5C_set_prefix(H5C_t * cache_ptr, char * prefix);
 
 H5_DLL herr_t H5C_set_skip_flags(H5C_t * cache_ptr,