[svn-r12592] Description:

    Several changes, all mooshed together:
        - Add support for "tiny" objects - which can be stored in the heap
            ID itself, instead of in the heap data blocks.
        - Flesh out support for compressed direct blocks, but comment it
            out until John's got some metadata cache changes in place to
            support it.
        - Add support for applying I/O pipeline filters to 'huge' objects
        - Refactor 'huge' object code to store information for 'huge' objects
            directly in the heap ID, when there are I/O pipeline filters
            applied to the heap (and the heap ID is large enough to hold the
            information)
        - Update h5debug tool to correctly handle 'huge' & 'tiny' objects.
        - Misc. other code cleanups, etc.

Tested on:
    FreeBSD/32 4.11 (sleipnir)
    Linux/64 2.4 (mir)
    Solaris/64 2.9 (shanti)

15 files changed, 2363 insertions, 361 deletions

diff --git a/src/H5HF.c b/src/H5HF.c
index 20d1aef..12822d5 100644
--- a/src/H5HF.c
+++ b/src/H5HF.c
@@ -334,11 +334,18 @@ HDfprintf(stderr, "%s: size = %Zu\n", FUNC, size);
     /* Get the fractal heap header */
     hdr = fh->hdr;
 
-    /* Check if object is large enough to be standalone */
+    /* Check for 'huge' object */
     if(size > hdr->max_man_size) {
         /* Store 'huge' object in heap */
-        if(H5HF_huge_insert(hdr, dxpl_id, size, obj, id) < 0)
-            HGOTO_ERROR(H5E_HEAP, H5E_CANTALLOC, FAIL, "can't allocate space for 'managed' object in fractal heap")
+        /* (Casting away const OK - QAK) */
+        if(H5HF_huge_insert(hdr, dxpl_id, size, (void *)obj, id) < 0)
+            HGOTO_ERROR(H5E_HEAP, H5E_CANTINSERT, FAIL, "can't store 'huge' object in fractal heap")
+    } /* end if */
+    /* Check for 'tiny' object */
+    else if(size <= hdr->tiny_max_len) {
+        /* Store 'tiny' object in heap */
+        if(H5HF_tiny_insert(hdr, size, obj, id) < 0)
+            HGOTO_ERROR(H5E_HEAP, H5E_CANTINSERT, FAIL, "can't store 'tiny' object in fractal heap")
     } /* end if */
     else {
         /* Check if we are in "append only" mode, or if there's enough room for the object */
@@ -348,7 +355,7 @@ HGOTO_ERROR(H5E_HEAP, H5E_UNSUPPORTED, FAIL, "'write once' managed blocks not su
         else {
             /* Allocate space for object in 'managed' heap */
             if(H5HF_man_insert(hdr, dxpl_id, size, obj, id) < 0)
-                HGOTO_ERROR(H5E_HEAP, H5E_CANTALLOC, FAIL, "can't allocate space for 'managed' object in fractal heap")
+                HGOTO_ERROR(H5E_HEAP, H5E_CANTINSERT, FAIL, "can't store 'managed' object in fractal heap")
         } /* end else */
     } /* end else */
 
@@ -390,7 +397,7 @@ H5HF_get_obj_len(H5HF_t *fh, hid_t dxpl_id, const void *_id, size_t *obj_len_p)
     HDassert(obj_len_p);
 
     /* Get the ID flags */
-    id_flags = *id++;
+    id_flags = *id;
 
     /* Check for correct heap ID version */
     if((id_flags & H5HF_ID_VERS_MASK) != H5HF_ID_VERS_CURR)
@@ -398,6 +405,9 @@ H5HF_get_obj_len(H5HF_t *fh, hid_t dxpl_id, const void *_id, size_t *obj_len_p)
 
     /* Check type of object in heap */
     if((id_flags & H5HF_ID_TYPE_MASK) == H5HF_ID_TYPE_MAN) {
+        /* Skip over the flag byte */
+        id++;
+
         /* Skip over object offset */
         id += fh->hdr->heap_off_size;
 
@@ -408,6 +418,10 @@ H5HF_get_obj_len(H5HF_t *fh, hid_t dxpl_id, const void *_id, size_t *obj_len_p)
         if(H5HF_huge_get_obj_len(fh->hdr, dxpl_id, id, obj_len_p) < 0)
             HGOTO_ERROR(H5E_HEAP, H5E_CANTGET, FAIL, "can't get 'huge' object's length")
     } /* end if */
+    else if((id_flags & H5HF_ID_TYPE_MASK) == H5HF_ID_TYPE_TINY) {
+        if(H5HF_tiny_get_obj_len(fh->hdr, id, obj_len_p) < 0)
+            HGOTO_ERROR(H5E_HEAP, H5E_CANTGET, FAIL, "can't get 'tiny' object's length")
+    } /* end if */
     else {
 HDfprintf(stderr, "%s: Heap ID type not supported yet!\n", FUNC);
 HGOTO_ERROR(H5E_HEAP, H5E_UNSUPPORTED, FAIL, "heap ID type not supported yet")
@@ -448,7 +462,7 @@ H5HF_read(H5HF_t *fh, hid_t dxpl_id, const void *_id, void *obj/*out*/)
     HDassert(obj);
 
     /* Get the ID flags */
-    id_flags = *id++;
+    id_flags = *id;
 
     /* Check for correct heap ID version */
     if((id_flags & H5HF_ID_VERS_MASK) != H5HF_ID_VERS_CURR)
@@ -465,6 +479,11 @@ H5HF_read(H5HF_t *fh, hid_t dxpl_id, const void *_id, void *obj/*out*/)
         if(H5HF_huge_read(fh->hdr, dxpl_id, id, obj) < 0)
             HGOTO_ERROR(H5E_HEAP, H5E_CANTGET, FAIL, "can't read 'huge' object from fractal heap")
     } /* end if */
+    else if((id_flags & H5HF_ID_TYPE_MASK) == H5HF_ID_TYPE_TINY) {
+        /* Read 'tiny' object from file */
+        if(H5HF_tiny_read(fh->hdr, id, obj) < 0)
+            HGOTO_ERROR(H5E_HEAP, H5E_CANTGET, FAIL, "can't read 'tiny' object from fractal heap")
+    } /* end if */
     else {
 HDfprintf(stderr, "%s: Heap ID type not supported yet!\n", FUNC);
 HGOTO_ERROR(H5E_HEAP, H5E_UNSUPPORTED, FAIL, "heap ID type not supported yet")
@@ -505,7 +524,7 @@ H5HF_remove(H5HF_t *fh, hid_t dxpl_id, const void *_id)
     HDassert(id);
 
     /* Get the ID flags */
-    id_flags = *id++;
+    id_flags = *id;
 
     /* Check for correct heap ID version */
     if((id_flags & H5HF_ID_VERS_MASK) != H5HF_ID_VERS_CURR)
@@ -522,6 +541,11 @@ H5HF_remove(H5HF_t *fh, hid_t dxpl_id, const void *_id)
         if(H5HF_huge_remove(fh->hdr, dxpl_id, id) < 0)
             HGOTO_ERROR(H5E_HEAP, H5E_CANTREMOVE, FAIL, "can't remove 'huge' object from fractal heap")
     } /* end if */
+    else if((id_flags & H5HF_ID_TYPE_MASK) == H5HF_ID_TYPE_TINY) {
+        /* Remove 'tiny' object from heap statistics */
+        if(H5HF_tiny_remove(fh->hdr, id) < 0)
+            HGOTO_ERROR(H5E_HEAP, H5E_CANTREMOVE, FAIL, "can't remove 'tiny' object from fractal heap")
+    } /* end if */
     else {
 HDfprintf(stderr, "%s: Heap ID type not supported yet!\n", FUNC);
 HGOTO_ERROR(H5E_HEAP, H5E_UNSUPPORTED, FAIL, "heap ID type not supported yet")
@@ -596,7 +620,7 @@ HDfprintf(stderr, "%s; After iterator reset fh->hdr->rc = %Zu\n", FUNC, fh->hdr-
         /* Shut down the huge object information */
         /* (Can't put this in header "destroy" routine, because it has
          *      has the address of an object in the file, which might be
-         *      by the shutdown routine - QAK)
+         *      modified by the shutdown routine - QAK)
          */
         if(H5HF_huge_term(fh->hdr, dxpl_id) < 0)
             HGOTO_ERROR(H5E_HEAP, H5E_CANTRELEASE, FAIL, "can't release 'huge' object info")
@@ -693,7 +717,7 @@ HDfprintf(stderr, "%s: hdr->huge_bt2_addr = %a\n", FUNC, hdr->huge_bt2_addr);
     } /* end if */
 
     /* Release header's disk space */
-    if(H5MF_xfree(f, H5FD_MEM_FHEAP_HDR, dxpl_id, fh_addr, (hsize_t)H5HF_HEADER_SIZE(hdr)) < 0)
+    if(H5MF_xfree(f, H5FD_MEM_FHEAP_HDR, dxpl_id, fh_addr, (hsize_t)hdr->heap_size) < 0)
         HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to release fractal heap header")
 
     /* Finished deleting header */
diff --git a/src/H5HFbtree2.c b/src/H5HFbtree2.c
index 4a324aa..43fafd1 100644
--- a/src/H5HFbtree2.c
+++ b/src/H5HFbtree2.c
@@ -59,34 +59,104 @@
 /********************/
 
 /* v2 B-tree function callbacks */
-herr_t H5HF_huge_bt2_found(const void *nrecord, void *op_data);
-herr_t H5HF_huge_bt2_remove(const void *nrecord, void *op_data);
+herr_t H5HF_huge_bt2_indir_found(const void *nrecord, void *op_data);
+herr_t H5HF_huge_bt2_indir_remove(const void *nrecord, void *op_data);
+herr_t H5HF_huge_bt2_filt_indir_found(const void *nrecord, void *op_data);
+herr_t H5HF_huge_bt2_filt_indir_remove(const void *nrecord, void *op_data);
+herr_t H5HF_huge_bt2_dir_remove(const void *nrecord, void *op_data);
+herr_t H5HF_huge_bt2_filt_dir_found(const void *nrecord, void *op_data);
+herr_t H5HF_huge_bt2_filt_dir_remove(const void *nrecord, void *op_data);
 
 /* v2 B-tree driver callbacks */
-static herr_t H5HF_huge_btree2_store(const H5B2_class_t *cls, void *native, const void *udata);
-static herr_t H5HF_huge_btree2_retrieve(const H5B2_class_t *cls, void *udata, const void *native);
-static herr_t H5HF_huge_btree2_compare(const H5B2_class_t *cls, const void *rec1, const void *rec2);
-static herr_t H5HF_huge_btree2_encode(const H5F_t *f, const H5B2_class_t *cls, uint8_t *raw,
+static herr_t H5HF_huge_btree2_indir_store(void *native, const void *udata);
+static herr_t H5HF_huge_btree2_indir_retrieve(void *udata, const void *native);
+static herr_t H5HF_huge_btree2_indir_compare(const void *rec1, const void *rec2);
+static herr_t H5HF_huge_btree2_indir_encode(const H5F_t *f, uint8_t *raw,
     const void *native);
-static herr_t H5HF_huge_btree2_decode(const H5F_t *f, const H5B2_class_t *cls, const uint8_t *raw,
+static herr_t H5HF_huge_btree2_indir_decode(const H5F_t *f, const uint8_t *raw,
     void *native);
-static herr_t H5HF_huge_btree2_debug(FILE *stream, const H5F_t *f, hid_t dxpl_id,
-    int indent, int fwidth, const H5B2_class_t *cls, const void *record, const void *_udata);
+static herr_t H5HF_huge_btree2_indir_debug(FILE *stream, const H5F_t *f, hid_t dxpl_id,
+    int indent, int fwidth, const void *record, const void *_udata);
+
+static herr_t H5HF_huge_btree2_filt_indir_store(void *native, const void *udata);
+static herr_t H5HF_huge_btree2_filt_indir_retrieve(void *udata, const void *native);
+static herr_t H5HF_huge_btree2_filt_indir_compare(const void *rec1, const void *rec2);
+static herr_t H5HF_huge_btree2_filt_indir_encode(const H5F_t *f, uint8_t *raw,
+    const void *native);
+static herr_t H5HF_huge_btree2_filt_indir_decode(const H5F_t *f, const uint8_t *raw,
+    void *native);
+static herr_t H5HF_huge_btree2_filt_indir_debug(FILE *stream, const H5F_t *f, hid_t dxpl_id,
+    int indent, int fwidth, const void *record, const void *_udata);
+
+static herr_t H5HF_huge_btree2_dir_store(void *native, const void *udata);
+static herr_t H5HF_huge_btree2_dir_retrieve(void *udata, const void *native);
+static herr_t H5HF_huge_btree2_dir_compare(const void *rec1, const void *rec2);
+static herr_t H5HF_huge_btree2_dir_encode(const H5F_t *f, uint8_t *raw,
+    const void *native);
+static herr_t H5HF_huge_btree2_dir_decode(const H5F_t *f, const uint8_t *raw,
+    void *native);
+static herr_t H5HF_huge_btree2_dir_debug(FILE *stream, const H5F_t *f, hid_t dxpl_id,
+    int indent, int fwidth, const void *record, const void *_udata);
+
+static herr_t H5HF_huge_btree2_filt_dir_store(void *native, const void *udata);
+static herr_t H5HF_huge_btree2_filt_dir_retrieve(void *udata, const void *native);
+static herr_t H5HF_huge_btree2_filt_dir_compare(const void *rec1, const void *rec2);
+static herr_t H5HF_huge_btree2_filt_dir_encode(const H5F_t *f, uint8_t *raw,
+    const void *native);
+static herr_t H5HF_huge_btree2_filt_dir_decode(const H5F_t *f, const uint8_t *raw,
+    void *native);
+static herr_t H5HF_huge_btree2_filt_dir_debug(FILE *stream, const H5F_t *f, hid_t dxpl_id,
+    int indent, int fwidth, const void *record, const void *_udata);
 
 /*********************/
 /* Package Variables */
 /*********************/
-const H5B2_class_t H5HF_BTREE2[1]={{     /* B-tree class information */
-    H5B2_FHEAP_ID,              /* Type of B-tree */
-    0,                          /* Size of native record */
-                                /* (computed at run-time for each heap) */
-    NULL,                       /* Class private information */
-    H5HF_huge_btree2_store,          /* Record storage callback */
-    H5HF_huge_btree2_retrieve,       /* Record retrieval callback */
-    H5HF_huge_btree2_compare,        /* Record comparison callback */
-    H5HF_huge_btree2_encode,         /* Record encoding callback */
-    H5HF_huge_btree2_decode,         /* Record decoding callback */
-    H5HF_huge_btree2_debug           /* Record debugging callback */
+/* v2 B-tree class for indirectly accessed 'huge' objects */
+const H5B2_class_t H5HF_BT2_INDIR[1]={{     /* B-tree class information */
+    H5B2_FHEAP_HUGE_INDIR_ID,           /* Type of B-tree */
+    sizeof(H5HF_huge_bt2_indir_rec_t),  /* Size of native record */
+    H5HF_huge_btree2_indir_store,       /* Record storage callback */
+    H5HF_huge_btree2_indir_retrieve,    /* Record retrieval callback */
+    H5HF_huge_btree2_indir_compare,     /* Record comparison callback */
+    H5HF_huge_btree2_indir_encode,      /* Record encoding callback */
+    H5HF_huge_btree2_indir_decode,      /* Record decoding callback */
+    H5HF_huge_btree2_indir_debug        /* Record debugging callback */
+}};
+
+/* v2 B-tree class for indirectly accessed, filtered 'huge' objects */
+const H5B2_class_t H5HF_BT2_FILT_INDIR[1]={{     /* B-tree class information */
+    H5B2_FHEAP_HUGE_FILT_INDIR_ID,              /* Type of B-tree */
+    sizeof(H5HF_huge_bt2_filt_indir_rec_t),     /* Size of native record */
+    H5HF_huge_btree2_filt_indir_store,          /* Record storage callback */
+    H5HF_huge_btree2_filt_indir_retrieve,       /* Record retrieval callback */
+    H5HF_huge_btree2_filt_indir_compare,        /* Record comparison callback */
+    H5HF_huge_btree2_filt_indir_encode,         /* Record encoding callback */
+    H5HF_huge_btree2_filt_indir_decode,         /* Record decoding callback */
+    H5HF_huge_btree2_filt_indir_debug           /* Record debugging callback */
+}};
+
+/* v2 B-tree class for directly accessed 'huge' objects */
+const H5B2_class_t H5HF_BT2_DIR[1]={{     /* B-tree class information */
+    H5B2_FHEAP_HUGE_DIR_ID,             /* Type of B-tree */
+    sizeof(H5HF_huge_bt2_dir_rec_t),    /* Size of native record */
+    H5HF_huge_btree2_dir_store,         /* Record storage callback */
+    H5HF_huge_btree2_dir_retrieve,      /* Record retrieval callback */
+    H5HF_huge_btree2_dir_compare,       /* Record comparison callback */
+    H5HF_huge_btree2_dir_encode,        /* Record encoding callback */
+    H5HF_huge_btree2_dir_decode,        /* Record decoding callback */
+    H5HF_huge_btree2_dir_debug          /* Record debugging callback */
+}};
+
+/* v2 B-tree class for directly accessed, filtered 'huge' objects */
+const H5B2_class_t H5HF_BT2_FILT_DIR[1]={{     /* B-tree class information */
+    H5B2_FHEAP_HUGE_FILT_DIR_ID,        /* Type of B-tree */
+    sizeof(H5HF_huge_bt2_filt_dir_rec_t),/* Size of native record */
+    H5HF_huge_btree2_filt_dir_store,    /* Record storage callback */
+    H5HF_huge_btree2_filt_dir_retrieve, /* Record retrieval callback */
+    H5HF_huge_btree2_filt_dir_compare,  /* Record comparison callback */
+    H5HF_huge_btree2_filt_dir_encode,   /* Record encoding callback */
+    H5HF_huge_btree2_filt_dir_decode,   /* Record decoding callback */
+    H5HF_huge_btree2_filt_dir_debug     /* Record debugging callback */
 }};
 
 /*****************************/
@@ -100,10 +170,10 @@ const H5B2_class_t H5HF_BTREE2[1]={{     /* B-tree class information */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HF_huge_bt2_found
+ * Function:	H5HF_huge_bt2_indir_found
  *
- * Purpose:	Retrieve record for 'huge' object, when it's found in the
- *              v2 B-tree
+ * Purpose:	Retrieve record for indirectly accessed 'huge' object, when
+ *              it's found in the v2 B-tree
  *
  * Return:	Success:	non-negative
  *		Failure:	negative
@@ -114,26 +184,27 @@ const H5B2_class_t H5HF_BTREE2[1]={{     /* B-tree class information */
  *-------------------------------------------------------------------------
  */
 herr_t
-H5HF_huge_bt2_found(const void *nrecord, void *op_data)
+H5HF_huge_bt2_indir_found(const void *nrecord, void *op_data)
 {
-    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_bt2_found)
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_bt2_indir_found)
 
 #ifdef QAK
-HDfprintf(stderr, "%s: nrecord = {%a, %Hu, %Hu}\n", "H5HF_huge_bt2_store",
-        ((const H5HF_huge_bt2_rec_t *)nrecord)->addr,
-        ((const H5HF_huge_bt2_rec_t *)nrecord)->len,
-        ((const H5HF_huge_bt2_rec_t *)nrecord)->id);
+HDfprintf(stderr, "%s: nrecord = {%a, %Hu, %Hu}\n", "H5HF_huge_bt2_indir_found",
+        ((const H5HF_huge_bt2_indir_rec_t *)nrecord)->addr,
+        ((const H5HF_huge_bt2_indir_rec_t *)nrecord)->len,
+        ((const H5HF_huge_bt2_indir_rec_t *)nrecord)->id);
 #endif /* QAK */
-    *(H5HF_huge_bt2_rec_t *)op_data = *(const H5HF_huge_bt2_rec_t *)nrecord;
+    *(H5HF_huge_bt2_indir_rec_t *)op_data = *(const H5HF_huge_bt2_indir_rec_t *)nrecord;
 
     FUNC_LEAVE_NOAPI(SUCCEED)
-} /* H5HF_huge_bt2_found() */
+} /* H5HF_huge_bt2_indir_found() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HF_huge_bt2_remove
+ * Function:	H5HF_huge_bt2_indir_remove
  *
- * Purpose:	Free space for 'huge' object, as v2 B-tree is being deleted
+ * Purpose:	Free space for indirectly accessed 'huge' object, as v2 B-tree
+ *              is being deleted or v2 B-tree node is removed
  *
  * Return:	Success:	non-negative
  *		Failure:	negative
@@ -144,32 +215,55 @@ HDfprintf(stderr, "%s: nrecord = {%a, %Hu, %Hu}\n", "H5HF_huge_bt2_store",
  *-------------------------------------------------------------------------
  */
 herr_t
-H5HF_huge_bt2_remove(const void *nrecord, void *_udata)
+H5HF_huge_bt2_indir_remove(const void *nrecord, void *_udata)
 {
     H5HF_huge_remove_ud1_t *udata = (H5HF_huge_remove_ud1_t *)_udata;   /* User callback data */
     herr_t ret_value = SUCCEED;         /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT(H5HF_huge_bt2_remove)
+    FUNC_ENTER_NOAPI_NOINIT(H5HF_huge_bt2_indir_remove)
 
     /* Free the space in the file for the object being removed */
-    if(H5MF_xfree(udata->hdr->f, H5FD_MEM_FHEAP_HUGE_OBJ, udata->dxpl_id, ((const H5HF_huge_bt2_rec_t *)nrecord)->addr, ((const H5HF_huge_bt2_rec_t *)nrecord)->len) < 0)
+    if(H5MF_xfree(udata->hdr->f, H5FD_MEM_FHEAP_HUGE_OBJ, udata->dxpl_id, ((const H5HF_huge_bt2_indir_rec_t *)nrecord)->addr, ((const H5HF_huge_bt2_indir_rec_t *)nrecord)->len) < 0)
         HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to free space for huge object on disk")
 
     /* Set the length of the object removed */
-    udata->obj_len = ((const H5HF_huge_bt2_rec_t *)nrecord)->len;
+    udata->obj_len = ((const H5HF_huge_bt2_indir_rec_t *)nrecord)->len;
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* H5HF_huge_bt2_remove() */
+} /* H5HF_huge_bt2_indir_remove() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HF_huge_btree2_store
+ * Function:	H5HF_huge_btree2_indir_store
  *
  * Purpose:	Store native information into record for v2 B-tree
  *
  * Return:	Success:	non-negative
+ *		Failure:	negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Monday, August  7, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5HF_huge_btree2_indir_store(void *nrecord, const void *udata)
+{
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_btree2_indir_store)
+
+    *(H5HF_huge_bt2_indir_rec_t *)nrecord = *(const H5HF_huge_bt2_indir_rec_t *)udata;
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* H5HF_huge_btree2_indir_store() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_huge_btree2_indir_retrieve
+ *
+ * Purpose:	Retrieve native information from record for v2 B-tree
  *
+ * Return:	Success:	non-negative
  *		Failure:	negative
  *
  * Programmer:	Quincey Koziol
@@ -178,23 +272,319 @@ done:
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5HF_huge_btree2_store(const H5B2_class_t UNUSED *cls, void *nrecord, const void *udata)
+H5HF_huge_btree2_indir_retrieve(void *udata, const void *nrecord)
 {
-    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_btree2_store)
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_btree2_indir_retrieve)
 
-    *(H5HF_huge_bt2_rec_t *)nrecord = *(const H5HF_huge_bt2_rec_t *)udata;
+    *(H5HF_huge_bt2_indir_rec_t *)udata = *(const H5HF_huge_bt2_indir_rec_t *)nrecord;
 
     FUNC_LEAVE_NOAPI(SUCCEED)
-} /* H5HF_huge_btree2_store() */
+} /* H5HF_huge_btree2_indir_retrieve() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_huge_btree2_indir_compare
+ *
+ * Purpose:	Compare two native information records, according to some key
+ *
+ * Return:	<0 if rec1 < rec2
+ *              =0 if rec1 == rec2
+ *              >0 if rec1 > rec2
+ *
+ * Programmer:	Quincey Koziol
+ *              Monday, August  7, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5HF_huge_btree2_indir_compare(const void *_rec1, const void *_rec2)
+{
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_btree2_indir_compare)
+
+#ifdef QAK
+{
+const H5HF_huge_bt2_indir_rec_t *rec1 = (const H5HF_huge_bt2_indir_rec_t *)_rec1;
+const H5HF_huge_bt2_indir_rec_t *rec2 = (const H5HF_huge_bt2_indir_rec_t *)_rec2;
+
+HDfprintf(stderr, "%s: rec1 = {%a, %Hu, %Hu}\n", "H5HF_huge_btree2_indir_compare", rec1->addr, rec1->len, rec1->id);
+HDfprintf(stderr, "%s: rec2 = {%a, %Hu, %Hu}\n", "H5HF_huge_btree2_indir_compare", rec2->addr, rec2->len, rec2->id);
+}
+#endif /* QAK */
+    FUNC_LEAVE_NOAPI((herr_t)(((const H5HF_huge_bt2_indir_rec_t *)_rec1)->id - ((const H5HF_huge_bt2_indir_rec_t *)_rec2)->id))
+} /* H5HF_huge_btree2_indir_compare() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HF_huge_btree2_retrieve
+ * Function:	H5HF_huge_btree2_indir_encode
+ *
+ * Purpose:	Encode native information into raw form for storing on disk
+ *
+ * Return:	Success:	non-negative
+ *		Failure:	negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Monday, August  7, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5HF_huge_btree2_indir_encode(const H5F_t *f, uint8_t *raw, const void *_nrecord)
+{
+    const H5HF_huge_bt2_indir_rec_t *nrecord = (const H5HF_huge_bt2_indir_rec_t *)_nrecord;
+
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_btree2_indir_encode)
+
+    /* Encode the record's fields */
+    H5F_addr_encode(f, &raw, nrecord->addr);
+    H5F_ENCODE_LENGTH(f, raw, nrecord->len);
+    H5F_ENCODE_LENGTH(f, raw, nrecord->id);
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* H5HF_huge_btree2_indir_encode() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_huge_btree2_indir_decode
+ *
+ * Purpose:	Decode raw disk form of record into native form
+ *
+ * Return:	Success:	non-negative
+ *		Failure:	negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Monday, August  7, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5HF_huge_btree2_indir_decode(const H5F_t *f, const uint8_t *raw, void *_nrecord)
+{
+    H5HF_huge_bt2_indir_rec_t *nrecord = (H5HF_huge_bt2_indir_rec_t *)_nrecord;
+
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_btree2_indir_decode)
+
+    /* Decode the record's fields */
+    H5F_addr_decode(f, &raw, &nrecord->addr);
+    H5F_DECODE_LENGTH(f, raw, nrecord->len);
+    H5F_DECODE_LENGTH(f, raw, nrecord->id);
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* H5HF_huge_btree2_indir_decode() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_huge_btree2_indir_debug
+ *
+ * Purpose:	Debug native form of record
+ *
+ * Return:	Success:	non-negative
+ *		Failure:	negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Monday, August  7, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5HF_huge_btree2_indir_debug(FILE *stream, const H5F_t UNUSED *f, hid_t UNUSED dxpl_id,
+    int indent, int fwidth, const void *_nrecord,
+    const void UNUSED *_udata)
+{
+    const H5HF_huge_bt2_indir_rec_t *nrecord = (const H5HF_huge_bt2_indir_rec_t *)_nrecord;
+
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_btree2_indir_debug)
+
+    HDfprintf(stream, "%*s%-*s {%a, %Hu, %Hu}\n", indent, "", fwidth, "Record:",
+        nrecord->addr, nrecord->len, nrecord->id);
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* H5HF_huge_btree2_indir_debug() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_huge_bt2_filt_indir_found
+ *
+ * Purpose:	Retrieve record for indirectly accessed, filtered 'huge' object,
+ *              when it's found in the v2 B-tree
+ *
+ * Return:	Success:	non-negative
+ *		Failure:	negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Tuesday, August  8, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5HF_huge_bt2_filt_indir_found(const void *nrecord, void *op_data)
+{
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_bt2_filt_indir_found)
+
+#ifdef QAK
+HDfprintf(stderr, "%s: nrecord = {%a, %Hu, %x, %Hu, %Hu}\n", "H5HF_huge_bt2_filt_indir_found",
+        ((const H5HF_huge_bt2_filt_indir_rec_t *)nrecord)->addr,
+        ((const H5HF_huge_bt2_filt_indir_rec_t *)nrecord)->len,
+        ((const H5HF_huge_bt2_filt_indir_rec_t *)nrecord)->filter_mask,
+        ((const H5HF_huge_bt2_filt_indir_rec_t *)nrecord)->obj_size,
+        ((const H5HF_huge_bt2_filt_indir_rec_t *)nrecord)->id);
+#endif /* QAK */
+    *(H5HF_huge_bt2_filt_indir_rec_t *)op_data = *(const H5HF_huge_bt2_filt_indir_rec_t *)nrecord;
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* H5HF_huge_bt2_filt_indir_found() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_huge_bt2_filt_indir_remove
+ *
+ * Purpose:	Free space for indirectly accessed, filtered 'huge' object, as
+ *              v2 B-tree is being deleted or v2 B-tree node is removed
+ *
+ * Return:	Success:	non-negative
+ *		Failure:	negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Tuesday, August  8, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5HF_huge_bt2_filt_indir_remove(const void *nrecord, void *_udata)
+{
+    H5HF_huge_remove_ud1_t *udata = (H5HF_huge_remove_ud1_t *)_udata;   /* User callback data */
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT(H5HF_huge_bt2_filt_indir_remove)
+
+    /* Free the space in the file for the object being removed */
+    if(H5MF_xfree(udata->hdr->f, H5FD_MEM_FHEAP_HUGE_OBJ, udata->dxpl_id, ((const H5HF_huge_bt2_filt_indir_rec_t *)nrecord)->addr, ((const H5HF_huge_bt2_filt_indir_rec_t *)nrecord)->len) < 0)
+        HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to free space for huge object on disk")
+
+    /* Set the length of the object removed */
+    udata->obj_len = ((const H5HF_huge_bt2_filt_indir_rec_t *)nrecord)->obj_size;
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5HF_huge_bt2_filt_indir_remove() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_huge_btree2_filt_indir_store
+ *
+ * Purpose:	Store native information into record for v2 B-tree
+ *
+ * Return:	Success:	non-negative
+ *		Failure:	negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Monday, August  7, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5HF_huge_btree2_filt_indir_store(void *nrecord, const void *udata)
+{
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_btree2_filt_indir_store)
+
+    *(H5HF_huge_bt2_filt_indir_rec_t *)nrecord = *(const H5HF_huge_bt2_filt_indir_rec_t *)udata;
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* H5HF_huge_btree2_filt_indir_store() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_huge_btree2_filt_indir_retrieve
  *
  * Purpose:	Retrieve native information from record for v2 B-tree
  *
  * Return:	Success:	non-negative
+ *		Failure:	negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Monday, August  7, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5HF_huge_btree2_filt_indir_retrieve(void *udata, const void *nrecord)
+{
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_btree2_filt_indir_retrieve)
+
+    *(H5HF_huge_bt2_filt_indir_rec_t *)udata = *(const H5HF_huge_bt2_filt_indir_rec_t *)nrecord;
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* H5HF_huge_btree2_filt_indir_retrieve() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_huge_btree2_filt_indir_compare
+ *
+ * Purpose:	Compare two native information records, according to some key
+ *
+ * Return:	<0 if rec1 < rec2
+ *              =0 if rec1 == rec2
+ *              >0 if rec1 > rec2
+ *
+ * Programmer:	Quincey Koziol
+ *              Monday, August  7, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5HF_huge_btree2_filt_indir_compare(const void *_rec1, const void *_rec2)
+{
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_btree2_filt_indir_compare)
+
+#ifdef QAK
+{
+const H5HF_huge_bt2_filt_indir_rec_t *rec1 = (const H5HF_huge_bt2_filt_indir_rec_t *)_rec1;
+const H5HF_huge_bt2_filt_indir_rec_t *rec2 = (const H5HF_huge_bt2_filt_indir_rec_t *)_rec2;
+
+HDfprintf(stderr, "%s: rec1 = {%a, %Hu, %x, %Hu, %Hu}\n", "H5HF_huge_btree2_filt_indir_compare", rec1->addr, rec1->len, rec1->filter_mask, rec1->obj_size, rec1->id);
+HDfprintf(stderr, "%s: rec2 = {%a, %Hu, %x, %Hu, %Hu}\n", "H5HF_huge_btree2_filt_indir_compare", rec2->addr, rec2->len, rec2->filter_mask, rec2->obj_size, rec2->id);
+}
+#endif /* QAK */
+    FUNC_LEAVE_NOAPI((herr_t)(((const H5HF_huge_bt2_filt_indir_rec_t *)_rec1)->id - ((const H5HF_huge_bt2_filt_indir_rec_t *)_rec2)->id))
+} /* H5HF_huge_btree2_filt_indir_compare() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_huge_btree2_filt_indir_encode
+ *
+ * Purpose:	Encode native information into raw form for storing on disk
+ *
+ * Return:	Success:	non-negative
+ *		Failure:	negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Monday, August  7, 2006
  *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5HF_huge_btree2_filt_indir_encode(const H5F_t *f, uint8_t *raw, const void *_nrecord)
+{
+    const H5HF_huge_bt2_filt_indir_rec_t *nrecord = (const H5HF_huge_bt2_filt_indir_rec_t *)_nrecord;
+
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_btree2_filt_indir_encode)
+
+    /* Encode the record's fields */
+    H5F_addr_encode(f, &raw, nrecord->addr);
+    H5F_ENCODE_LENGTH(f, raw, nrecord->len);
+    UINT32ENCODE(raw, nrecord->filter_mask);
+    H5F_ENCODE_LENGTH(f, raw, nrecord->obj_size);
+    H5F_ENCODE_LENGTH(f, raw, nrecord->id);
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* H5HF_huge_btree2_filt_indir_encode() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_huge_btree2_filt_indir_decode
+ *
+ * Purpose:	Decode raw disk form of record into native form
+ *
+ * Return:	Success:	non-negative
  *		Failure:	negative
  *
  * Programmer:	Quincey Koziol
@@ -203,18 +593,136 @@ H5HF_huge_btree2_store(const H5B2_class_t UNUSED *cls, void *nrecord, const void
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5HF_huge_btree2_retrieve(const H5B2_class_t UNUSED *cls, void *udata, const void *nrecord)
+H5HF_huge_btree2_filt_indir_decode(const H5F_t *f, const uint8_t *raw, void *_nrecord)
 {
-    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_btree2_retrieve)
+    H5HF_huge_bt2_filt_indir_rec_t *nrecord = (H5HF_huge_bt2_filt_indir_rec_t *)_nrecord;
+
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_btree2_filt_indir_decode)
 
-    *(H5HF_huge_bt2_rec_t *)udata = *(const H5HF_huge_bt2_rec_t *)nrecord;
+    /* Decode the record's fields */
+    H5F_addr_decode(f, &raw, &nrecord->addr);
+    H5F_DECODE_LENGTH(f, raw, nrecord->len);
+    UINT32DECODE(raw, nrecord->filter_mask);
+    H5F_DECODE_LENGTH(f, raw, nrecord->obj_size);
+    H5F_DECODE_LENGTH(f, raw, nrecord->id);
 
     FUNC_LEAVE_NOAPI(SUCCEED)
-} /* H5HF_huge_btree2_retrieve() */
+} /* H5HF_huge_btree2_filt_indir_decode() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HF_huge_btree2_compare
+ * Function:	H5HF_huge_btree2_filt_indir_debug
+ *
+ * Purpose:	Debug native form of record
+ *
+ * Return:	Success:	non-negative
+ *		Failure:	negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Monday, August  7, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5HF_huge_btree2_filt_indir_debug(FILE *stream, const H5F_t UNUSED *f, hid_t UNUSED dxpl_id,
+    int indent, int fwidth, const void *_nrecord,
+    const void UNUSED *_udata)
+{
+    const H5HF_huge_bt2_filt_indir_rec_t *nrecord = (const H5HF_huge_bt2_filt_indir_rec_t *)_nrecord;
+
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_btree2_filt_indir_debug)
+
+    HDfprintf(stream, "%*s%-*s {%a, %Hu, %x, %Hu, %Hu}\n", indent, "", fwidth, "Record:",
+        nrecord->addr, nrecord->len, nrecord->filter_mask, nrecord->obj_size, nrecord->id);
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* H5HF_huge_btree2_filt_indir_debug() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_huge_bt2_dir_remove
+ *
+ * Purpose:	Free space for directly accessed 'huge' object, as v2 B-tree
+ *              is being deleted or v2 B-tree node is being removed
+ *
+ * Return:	Success:	non-negative
+ *		Failure:	negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Tuesday, August  8, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5HF_huge_bt2_dir_remove(const void *nrecord, void *_udata)
+{
+    H5HF_huge_remove_ud1_t *udata = (H5HF_huge_remove_ud1_t *)_udata;   /* User callback data */
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT(H5HF_huge_bt2_dir_remove)
+
+    /* Free the space in the file for the object being removed */
+    if(H5MF_xfree(udata->hdr->f, H5FD_MEM_FHEAP_HUGE_OBJ, udata->dxpl_id, ((const H5HF_huge_bt2_indir_rec_t *)nrecord)->addr, ((const H5HF_huge_bt2_indir_rec_t *)nrecord)->len) < 0)
+        HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to free space for huge object on disk")
+
+    /* Set the length of the object removed */
+    udata->obj_len = ((const H5HF_huge_bt2_indir_rec_t *)nrecord)->len;
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5HF_huge_bt2_dir_remove() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_huge_btree2_dir_store
+ *
+ * Purpose:	Store native information into record for v2 B-tree
+ *
+ * Return:	Success:	non-negative
+ *		Failure:	negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Monday, August  7, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5HF_huge_btree2_dir_store(void *nrecord, const void *udata)
+{
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_btree2_dir_store)
+
+    *(H5HF_huge_bt2_dir_rec_t *)nrecord = *(const H5HF_huge_bt2_dir_rec_t *)udata;
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* H5HF_huge_btree2_dir_store() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_huge_btree2_dir_retrieve
+ *
+ * Purpose:	Retrieve native information from record for v2 B-tree
+ *
+ * Return:	Success:	non-negative
+ *		Failure:	negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Monday, August  7, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5HF_huge_btree2_dir_retrieve(void *udata, const void *nrecord)
+{
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_btree2_dir_retrieve)
+
+    *(H5HF_huge_bt2_dir_rec_t *)udata = *(const H5HF_huge_bt2_dir_rec_t *)nrecord;
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* H5HF_huge_btree2_dir_retrieve() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_huge_btree2_dir_compare
  *
  * Purpose:	Compare two native information records, according to some key
  *
@@ -228,47 +736,39 @@ H5HF_huge_btree2_retrieve(const H5B2_class_t UNUSED *cls, void *udata, const voi
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5HF_huge_btree2_compare(const H5B2_class_t *cls, const void *_rec1, const void *_rec2)
+H5HF_huge_btree2_dir_compare(const void *_rec1, const void *_rec2)
 {
-    const H5HF_huge_bt2_rec_t *rec1 = (const H5HF_huge_bt2_rec_t *)_rec1;
-    const H5HF_huge_bt2_rec_t *rec2 = (const H5HF_huge_bt2_rec_t *)_rec2;
-    const H5HF_hdr_t *hdr = (const H5HF_hdr_t *)cls->cls_private;
+    const H5HF_huge_bt2_dir_rec_t *rec1 = (const H5HF_huge_bt2_dir_rec_t *)_rec1;
+    const H5HF_huge_bt2_dir_rec_t *rec2 = (const H5HF_huge_bt2_dir_rec_t *)_rec2;
     herr_t ret_value;           /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_btree2_compare)
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_btree2_dir_compare)
 
 #ifdef QAK
-HDfprintf(stderr, "%s: hdr->huge_ids_direct = %t\n", "H5HF_huge_btree2_compare", hdr->huge_ids_direct);
-HDfprintf(stderr, "%s: rec1 = {%a, %Hu, %Hu}\n", "H5HF_huge_btree2_compare", rec1->addr, rec1->len, rec1->id);
-HDfprintf(stderr, "%s: rec2 = {%a, %Hu, %Hu}\n", "H5HF_huge_btree2_compare", rec2->addr, rec2->len, rec2->id);
+HDfprintf(stderr, "%s: rec1 = {%a, %Hu}\n", "H5HF_huge_btree2_dir_compare", rec1->addr, rec1->len);
+HDfprintf(stderr, "%s: rec2 = {%a, %Hu}\n", "H5HF_huge_btree2_dir_compare", rec2->addr, rec2->len);
 #endif /* QAK */
-    /* Sort differently, depending on whether 'huge' object directly reference disk */
-    if(hdr->huge_ids_direct) {
-        if(rec1->addr < rec2->addr)
-            ret_value = -1;
-        else if(rec1->addr > rec2->addr)
-            ret_value = 1;
-        else if(rec1->len < rec2->len)
-            ret_value = -1;
-        else if(rec1->len > rec2->len)
-            ret_value = 1;
-        else
-            ret_value = 0;
-    } /* end if */
+    if(rec1->addr < rec2->addr)
+        ret_value = -1;
+    else if(rec1->addr > rec2->addr)
+        ret_value = 1;
+    else if(rec1->len < rec2->len)
+        ret_value = -1;
+    else if(rec1->len > rec2->len)
+        ret_value = 1;
     else
-        ret_value = (herr_t)(rec1->id - rec2->id);
+        ret_value = 0;
 
-    FUNC_LEAVE_NOAPI(ret_value);
-} /* H5HF_huge_btree2_compare() */
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5HF_huge_btree2_dir_compare() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HF_huge_btree2_encode
+ * Function:	H5HF_huge_btree2_dir_encode
  *
  * Purpose:	Encode native information into raw form for storing on disk
  *
  * Return:	Success:	non-negative
- *
  *		Failure:	negative
  *
  * Programmer:	Quincey Koziol
@@ -277,32 +777,26 @@ HDfprintf(stderr, "%s: rec2 = {%a, %Hu, %Hu}\n", "H5HF_huge_btree2_compare", rec
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5HF_huge_btree2_encode(const H5F_t *f, const H5B2_class_t *cls, uint8_t *raw, const void *_nrecord)
+H5HF_huge_btree2_dir_encode(const H5F_t *f, uint8_t *raw, const void *_nrecord)
 {
-    const H5HF_huge_bt2_rec_t *nrecord = (const H5HF_huge_bt2_rec_t *)_nrecord;
-    const H5HF_hdr_t *hdr = (const H5HF_hdr_t *)cls->cls_private;
+    const H5HF_huge_bt2_dir_rec_t *nrecord = (const H5HF_huge_bt2_dir_rec_t *)_nrecord;
 
-    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_btree2_encode)
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_btree2_dir_encode)
 
-    /* Encode the record's common fields */
+    /* Encode the record's fields */
     H5F_addr_encode(f, &raw, nrecord->addr);
     H5F_ENCODE_LENGTH(f, raw, nrecord->len);
 
-    /* If 'huge' objects in this heap are not accessed directly, encode the ID also */
-    if(!hdr->huge_ids_direct)
-        UINT64ENCODE_VAR(raw, nrecord->id, hdr->huge_id_size)
-
     FUNC_LEAVE_NOAPI(SUCCEED)
-} /* H5HF_huge_btree2_encode() */
+} /* H5HF_huge_btree2_dir_encode() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HF_huge_btree2_decode
+ * Function:	H5HF_huge_btree2_dir_decode
  *
  * Purpose:	Decode raw disk form of record into native form
  *
  * Return:	Success:	non-negative
- *
  *		Failure:	negative
  *
  * Programmer:	Quincey Koziol
@@ -311,34 +805,26 @@ H5HF_huge_btree2_encode(const H5F_t *f, const H5B2_class_t *cls, uint8_t *raw, c
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5HF_huge_btree2_decode(const H5F_t *f, const H5B2_class_t *cls, const uint8_t *raw, void *_nrecord)
+H5HF_huge_btree2_dir_decode(const H5F_t *f, const uint8_t *raw, void *_nrecord)
 {
-    H5HF_huge_bt2_rec_t *nrecord = (H5HF_huge_bt2_rec_t *)_nrecord;
-    const H5HF_hdr_t *hdr = (const H5HF_hdr_t *)cls->cls_private;
+    H5HF_huge_bt2_dir_rec_t *nrecord = (H5HF_huge_bt2_dir_rec_t *)_nrecord;
 
-    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_btree2_decode)
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_btree2_dir_decode)
 
-    /* Decode the record's common fields */
+    /* Decode the record's fields */
     H5F_addr_decode(f, &raw, &nrecord->addr);
     H5F_DECODE_LENGTH(f, raw, nrecord->len);
 
-    /* If 'huge' objects in this heap are not accessed directly, decode the ID also */
-    if(!hdr->huge_ids_direct)
-        UINT64DECODE_VAR(raw, nrecord->id, hdr->huge_id_size)
-    else
-        nrecord->id = 0;
-
     FUNC_LEAVE_NOAPI(SUCCEED)
-} /* H5HF_huge_btree2_decode() */
+} /* H5HF_huge_btree2_dir_decode() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HF_huge_btree2_debug
+ * Function:	H5HF_huge_btree2_dir_debug
  *
  * Purpose:	Debug native form of record
  *
  * Return:	Success:	non-negative
- *
  *		Failure:	negative
  *
  * Programmer:	Quincey Koziol
@@ -347,24 +833,261 @@ H5HF_huge_btree2_decode(const H5F_t *f, const H5B2_class_t *cls, const uint8_t *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5HF_huge_btree2_debug(FILE *stream, const H5F_t UNUSED *f, hid_t UNUSED dxpl_id,
-    int indent, int fwidth, const H5B2_class_t *cls, const void *_nrecord,
+H5HF_huge_btree2_dir_debug(FILE *stream, const H5F_t UNUSED *f, hid_t UNUSED dxpl_id,
+    int indent, int fwidth, const void *_nrecord,
     const void UNUSED *_udata)
 {
-    const H5HF_huge_bt2_rec_t *nrecord = (const H5HF_huge_bt2_rec_t *)_nrecord;
-    const H5HF_hdr_t *hdr = (const H5HF_hdr_t *)cls->cls_private;
+    const H5HF_huge_bt2_dir_rec_t *nrecord = (const H5HF_huge_bt2_dir_rec_t *)_nrecord;
+
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_btree2_dir_debug)
+
+    HDfprintf(stream, "%*s%-*s {%a, %Hu}\n", indent, "", fwidth, "Record:",
+        nrecord->addr, nrecord->len);
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* H5HF_huge_btree2_dir_debug() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_huge_bt2_filt_dir_found
+ *
+ * Purpose:	Retrieve record for directly accessed, filtered 'huge' object,
+ *              when it's found in the v2 B-tree
+ *
+ * Return:	Success:	non-negative
+ *		Failure:	negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Tuesday, August 15, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5HF_huge_bt2_filt_dir_found(const void *nrecord, void *op_data)
+{
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_bt2_filt_dir_found)
+
+#ifdef QAK
+HDfprintf(stderr, "%s: nrecord = {%a, %Hu, %x, %Hu}\n", "H5HF_huge_bt2_filt_dir_found",
+        ((const H5HF_huge_bt2_filt_dir_rec_t *)nrecord)->addr,
+        ((const H5HF_huge_bt2_filt_dir_rec_t *)nrecord)->len,
+        ((const H5HF_huge_bt2_filt_dir_rec_t *)nrecord)->filter_mask,
+        ((const H5HF_huge_bt2_filt_dir_rec_t *)nrecord)->obj_size);
+#endif /* QAK */
+    *(H5HF_huge_bt2_filt_dir_rec_t *)op_data = *(const H5HF_huge_bt2_filt_dir_rec_t *)nrecord;
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* H5HF_huge_bt2_filt_dir_found() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_huge_bt2_filt_dir_remove
+ *
+ * Purpose:	Free space for directly accessed, filtered 'huge' object, as
+ *              v2 B-tree is being deleted or v2 B-tree node is removed
+ *
+ * Return:	Success:	non-negative
+ *		Failure:	negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Tuesday, August 15, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5HF_huge_bt2_filt_dir_remove(const void *nrecord, void *_udata)
+{
+    H5HF_huge_remove_ud1_t *udata = (H5HF_huge_remove_ud1_t *)_udata;   /* User callback data */
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT(H5HF_huge_bt2_filt_dir_remove)
+
+    /* Free the space in the file for the object being removed */
+    if(H5MF_xfree(udata->hdr->f, H5FD_MEM_FHEAP_HUGE_OBJ, udata->dxpl_id, ((const H5HF_huge_bt2_filt_dir_rec_t *)nrecord)->addr, ((const H5HF_huge_bt2_filt_dir_rec_t *)nrecord)->len) < 0)
+        HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to free space for huge object on disk")
+
+    /* Set the length of the object removed */
+    udata->obj_len = ((const H5HF_huge_bt2_filt_dir_rec_t *)nrecord)->obj_size;
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5HF_huge_bt2_filt_dir_remove() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_huge_btree2_filt_dir_store
+ *
+ * Purpose:	Store native information into record for v2 B-tree
+ *
+ * Return:	Success:	non-negative
+ *		Failure:	negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Tuesday, August 15, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5HF_huge_btree2_filt_dir_store(void *nrecord, const void *udata)
+{
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_btree2_filt_dir_store)
+
+    *(H5HF_huge_bt2_filt_dir_rec_t *)nrecord = *(const H5HF_huge_bt2_filt_dir_rec_t *)udata;
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* H5HF_huge_btree2_filt_dir_store() */
 
-    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_btree2_debug)
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_huge_btree2_filt_dir_retrieve
+ *
+ * Purpose:	Retrieve native information from record for v2 B-tree
+ *
+ * Return:	Success:	non-negative
+ *		Failure:	negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Tuesday, August 15, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5HF_huge_btree2_filt_dir_retrieve(void *udata, const void *nrecord)
+{
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_btree2_filt_dir_retrieve)
+
+    *(H5HF_huge_bt2_filt_dir_rec_t *)udata = *(const H5HF_huge_bt2_filt_dir_rec_t *)nrecord;
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* H5HF_huge_btree2_filt_dir_retrieve() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_huge_btree2_filt_dir_compare
+ *
+ * Purpose:	Compare two native information records, according to some key
+ *
+ * Return:	<0 if rec1 < rec2
+ *              =0 if rec1 == rec2
+ *              >0 if rec1 > rec2
+ *
+ * Programmer:	Quincey Koziol
+ *              Tuesday, August 15, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5HF_huge_btree2_filt_dir_compare(const void *_rec1, const void *_rec2)
+{
+    const H5HF_huge_bt2_filt_dir_rec_t *rec1 = (const H5HF_huge_bt2_filt_dir_rec_t *)_rec1;
+    const H5HF_huge_bt2_filt_dir_rec_t *rec2 = (const H5HF_huge_bt2_filt_dir_rec_t *)_rec2;
+    herr_t ret_value;           /* Return value */
 
-    HDassert(nrecord);
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_btree2_filt_dir_compare)
 
-    if(hdr->huge_ids_direct)
-        HDfprintf(stream, "%*s%-*s {%a, %Hu}\n", indent, "", fwidth, "Record:",
-            nrecord->addr, nrecord->len);
+#ifdef QAK
+HDfprintf(stderr, "%s: rec1 = {%a, %Hu, %x, %Hu}\n", "H5HF_huge_btree2_filt_dir_compare", rec1->addr, rec1->len, rec1->filter_mask, rec1->obj_size);
+HDfprintf(stderr, "%s: rec2 = {%a, %Hu, %x, %Hu}\n", "H5HF_huge_btree2_filt_dir_compare", rec2->addr, rec2->len, rec2->filter_mask, rec2->obj_size);
+#endif /* QAK */
+    if(rec1->addr < rec2->addr)
+        ret_value = -1;
+    else if(rec1->addr > rec2->addr)
+        ret_value = 1;
+    else if(rec1->len < rec2->len)
+        ret_value = -1;
+    else if(rec1->len > rec2->len)
+        ret_value = 1;
     else
-        HDfprintf(stream, "%*s%-*s {%a, %Hu, %Hu}\n", indent, "", fwidth, "Record:",
-            nrecord->addr, nrecord->len, nrecord->id);
+        ret_value = 0;
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5HF_huge_btree2_filt_dir_compare() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_huge_btree2_filt_dir_encode
+ *
+ * Purpose:	Encode native information into raw form for storing on disk
+ *
+ * Return:	Success:	non-negative
+ *		Failure:	negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Tuesday, August 15, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5HF_huge_btree2_filt_dir_encode(const H5F_t *f, uint8_t *raw, const void *_nrecord)
+{
+    const H5HF_huge_bt2_filt_dir_rec_t *nrecord = (const H5HF_huge_bt2_filt_dir_rec_t *)_nrecord;
+
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_btree2_filt_dir_encode)
+
+    /* Encode the record's fields */
+    H5F_addr_encode(f, &raw, nrecord->addr);
+    H5F_ENCODE_LENGTH(f, raw, nrecord->len);
+    UINT32ENCODE(raw, nrecord->filter_mask);
+    H5F_ENCODE_LENGTH(f, raw, nrecord->obj_size);
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* H5HF_huge_btree2_filt_dir_encode() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_huge_btree2_filt_dir_decode
+ *
+ * Purpose:	Decode raw disk form of record into native form
+ *
+ * Return:	Success:	non-negative
+ *		Failure:	negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Tuesday, August 15, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5HF_huge_btree2_filt_dir_decode(const H5F_t *f, const uint8_t *raw, void *_nrecord)
+{
+    H5HF_huge_bt2_filt_dir_rec_t *nrecord = (H5HF_huge_bt2_filt_dir_rec_t *)_nrecord;
+
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_btree2_filt_dir_decode)
+
+    /* Decode the record's fields */
+    H5F_addr_decode(f, &raw, &nrecord->addr);
+    H5F_DECODE_LENGTH(f, raw, nrecord->len);
+    UINT32DECODE(raw, nrecord->filter_mask);
+    H5F_DECODE_LENGTH(f, raw, nrecord->obj_size);
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* H5HF_huge_btree2_filt_dir_decode() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_huge_btree2_filt_dir_debug
+ *
+ * Purpose:	Debug native form of record
+ *
+ * Return:	Success:	non-negative
+ *		Failure:	negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Tuesday, August 15, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5HF_huge_btree2_filt_dir_debug(FILE *stream, const H5F_t UNUSED *f, hid_t UNUSED dxpl_id,
+    int indent, int fwidth, const void *_nrecord, const void UNUSED *_udata)
+{
+    const H5HF_huge_bt2_filt_dir_rec_t *nrecord = (const H5HF_huge_bt2_filt_dir_rec_t *)_nrecord;
+
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_huge_btree2_filt_dir_debug)
+
+    HDfprintf(stream, "%*s%-*s {%a, %Hu, %x, %Hu}\n", indent, "", fwidth, "Record:",
+        nrecord->addr, nrecord->len, nrecord->filter_mask, nrecord->obj_size);
 
     FUNC_LEAVE_NOAPI(SUCCEED)
-} /* H5HF_huge_btree2_debug() */
+} /* H5HF_huge_btree2_filt_dir_debug() */
 
diff --git a/src/H5HFcache.c b/src/H5HFcache.c
index e174260..63e4e46 100644
--- a/src/H5HFcache.c
+++ b/src/H5HFcache.c
@@ -35,6 +35,7 @@
 #include "H5private.h"		/* Generic Functions			*/
 #include "H5Eprivate.h"		/* Error handling		  	*/
 #include "H5HFpkg.h"		/* Fractal heaps			*/
+#include "H5MMprivate.h"	/* Memory management			*/
 #include "H5Vprivate.h"		/* Vectors and arrays 			*/
 
 /****************/
@@ -309,8 +310,9 @@ HDfprintf(stderr, "%s: Load heap header, addr = %a\n", FUNC, addr);
     if(metadata_chksum != 0)
 	HGOTO_ERROR(H5E_HEAP, H5E_CANTLOAD, NULL, "incorrect metadata checksum for fractal heap header")
 
-    /* Heap ID length */
-    UINT16DECODE(p, hdr->id_len);
+    /* General heap information */
+    UINT16DECODE(p, hdr->id_len);               /* Heap ID length */
+    UINT16DECODE(p, hdr->filter_len);           /* I/O filters' encoded length */
 
     /* Heap status flags */
     /* (bit 0: "huge" object IDs have wrapped) */
@@ -333,13 +335,62 @@ HDfprintf(stderr, "%s: Load heap header, addr = %a\n", FUNC, addr);
     H5F_DECODE_LENGTH(f, p, hdr->man_nobjs);
     H5F_DECODE_LENGTH(f, p, hdr->huge_size);
     H5F_DECODE_LENGTH(f, p, hdr->huge_nobjs);
+    H5F_DECODE_LENGTH(f, p, hdr->tiny_size);
+    H5F_DECODE_LENGTH(f, p, hdr->tiny_nobjs);
 
     /* Managed objects' doubling-table info */
     if(H5HF_dtable_decode(hdr->f, &p, &(hdr->man_dtable)) < 0)
         HGOTO_ERROR(H5E_HEAP, H5E_CANTENCODE, NULL, "unable to encode managed obj. doubling table info")
 
+    /* Sanity check */
     HDassert((size_t)(p - buf) == size);
 
+    /* Check for I/O filter information to decode */
+    if(hdr->filter_len > 0) {
+        size_t filter_info_size;        /* Size of filter information */
+        H5O_pline_t *pline;     /* Pipeline information from the header on disk */
+
+        /* Compute the size of the extra filter information */
+        filter_info_size = hdr->sizeof_size     /* Size of size for filtered root direct block */
+            + 4                                 /* Size of filter mask for filtered root direct block */
+            + hdr->filter_len;                  /* Size of encoded I/O filter info */
+
+        /* Check if the current buffer can be re-used, or needs to be re-sized */
+        if(filter_info_size > size) {
+            if((buf = H5FL_BLK_REALLOC(header_block, buf, filter_info_size)) == NULL)
+                HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, NULL, "can't allocate space to decode I/O pipeline filters")
+        } /* end if */
+
+        /* Read in I/O filter information */
+        if(H5F_block_read(f, H5FD_MEM_FHEAP_HDR, (addr + size), filter_info_size, dxpl_id, buf) < 0)
+            HGOTO_ERROR(H5E_HEAP, H5E_READERROR, NULL, "can't read fractal heap header's I/O pipeline filter info")
+
+        p = buf;
+
+        /* Decode the size of a filtered root direct block */
+        H5F_DECODE_LENGTH(f, p, hdr->pline_root_direct_size);
+
+        /* Decode the filter mask for a filtered root direct block */
+        UINT32DECODE(p, hdr->pline_root_direct_filter_mask);
+
+        /* Decode I/O filter information */
+        if(NULL == (pline = H5O_decode(hdr->f, p, H5O_PLINE_ID)))
+            HGOTO_ERROR(H5E_HEAP, H5E_CANTDECODE, NULL, "can't decode I/O pipeline filters")
+
+        /* Copy the information into the header's I/O pipeline structure */
+        if(NULL == H5O_copy(H5O_PLINE_ID, pline, &(hdr->pline)))
+            HGOTO_ERROR(H5E_HEAP, H5E_CANTCOPY, NULL, "can't copy I/O filter pipeline")
+
+        /* Release the space allocated for the I/O pipeline filters */
+        H5O_free(H5O_PLINE_ID, pline);
+
+        /* Compute the heap header's size */
+        hdr->heap_size = size + filter_info_size;
+    } /* end if */
+    else 
+        /* Set the heap header's size */
+        hdr->heap_size = size;
+
     /* Finish initialization of heap header */
     if(H5HF_hdr_finish_init(hdr) < 0)
 	HGOTO_ERROR(H5E_RESOURCE, H5E_CANTINIT, NULL, "can't finish initializing shared fractal heap header")
@@ -398,7 +449,7 @@ HDfprintf(stderr, "%s: Flushing heap header, addr = %a, destroy = %u\n", FUNC, a
         HDassert(hdr->dirty);
 
         /* Compute the size of the heap header on disk */
-        size = H5HF_HEADER_SIZE(hdr);
+        size = hdr->heap_size;
 
         /* Allocate temporary buffer */
         if((buf = H5FL_BLK_MALLOC(header_block, size)) == NULL)
@@ -422,8 +473,9 @@ HDfprintf(stderr, "%s: Flushing heap header, addr = %a, destroy = %u\n", FUNC, a
         HDmemset(p, 0, (size_t)4);
         p += 4;
 
-        /* Heap ID length */
-        UINT16ENCODE(p, hdr->id_len);
+        /* 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) */
@@ -447,11 +499,27 @@ HDfprintf(stderr, "%s: Flushing heap header, addr = %a, destroy = %u\n", FUNC, a
         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);
+
+            /* Encode the filter mask for a filtered root direct block */
+            UINT32ENCODE(p, hdr->pline_root_direct_filter_mask);
+
+            /* Encode I/O filter information */
+            if(H5O_encode(hdr->f, p, &(hdr->pline), H5O_PLINE_ID) < 0)
+                HGOTO_ERROR(H5E_HEAP, H5E_CANTENCODE, FAIL, "can't encode I/O pipeline fiters")
+            p += hdr->filter_len;
+        } /* end if */
+
 	/* 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)
@@ -500,6 +568,10 @@ H5HF_cache_hdr_dest(H5F_t UNUSED *f, H5HF_hdr_t *hdr)
     /* Free the block size lookup table for the doubling table */
     H5HF_dtable_dest(&hdr->man_dtable);
 
+    /* Release any I/O pipeline filter information */
+    if(hdr->pline.nused)
+        H5O_reset(H5O_PLINE_ID, &(hdr->pline));
+
     /* Free the shared info itself */
     H5FL_FREE(H5HF_hdr_t, hdr);
 
@@ -570,7 +642,7 @@ H5HF_cache_hdr_size(const H5F_t UNUSED *f, const H5HF_hdr_t *hdr, size_t *size_p
     HDassert(size_ptr);
 
     /* Set size value */
-    *size_ptr = H5HF_HEADER_SIZE(hdr);
+    *size_ptr = hdr->heap_size;
 
     FUNC_LEAVE_NOAPI(SUCCEED)
 } /* H5HF_cache_hdr_size() */
@@ -595,6 +667,7 @@ static H5HF_direct_t *
 H5HF_cache_dblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, const void *_size, void *_par_info)
 {
     const size_t        *size = (const size_t *)_size;         /* Size of block */
+    H5HF_hdr_t          *hdr;           /* Shared fractal heap information */
     H5HF_parent_t       *par_info = (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 */
@@ -614,11 +687,22 @@ H5HF_cache_dblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, const void *_size,
 	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 */
+    hdr = par_info->hdr;
+
     /* Share common heap information */
-    dblock->hdr = par_info->hdr;
-    if(H5HF_hdr_incr(dblock->hdr) < 0)
+    dblock->hdr = hdr;
+    if(H5HF_hdr_incr(hdr) < 0)
 	HGOTO_ERROR(H5E_HEAP, H5E_CANTINC, NULL, "can't increment reference count on shared heap header")
 
+#ifdef LATER
+    /* Check for I/O filters on this heap */
+    if(hdr->filter_len > 0) {
+HDfprintf(stderr, "%s: I/O filters not supported yet!\n", FUNC);
+HGOTO_ERROR(H5E_HEAP, H5E_UNSUPPORTED, NULL, "I/O filters not supported yet")
+    } /* end if */
+#endif /* LATER */
+
     /* Set block's internal information */
     dblock->size = *size;
     dblock->blk_off_size = H5HF_SIZEOF_OFFSET_LEN(dblock->size);
@@ -656,7 +740,7 @@ H5HF_cache_dblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, const void *_size,
 
     /* Address of heap that owns this block (skip) */
     H5F_addr_decode(f, &p, &heap_addr);
-    if(H5F_addr_ne(heap_addr, dblock->hdr->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")
 
     /* Address of parent block */
@@ -669,7 +753,7 @@ H5HF_cache_dblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, const void *_size,
     } /* end if */
 
     /* Offset of heap within the heap's address space */
-    UINT64DECODE_VAR(p, dblock->block_off, dblock->hdr->heap_off_size);
+    UINT64DECODE_VAR(p, dblock->block_off, hdr->heap_off_size);
 
     /* Set return value */
     ret_value = dblock;
@@ -709,6 +793,8 @@ H5HF_cache_dblock_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr,
 
     if(dblock->cache_info.is_dirty) {
         H5HF_hdr_t *hdr;        /* Shared fractal heap information */
+        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 */
 
         /* Get the pointer to the shared heap header */
@@ -742,10 +828,46 @@ H5HF_cache_dblock_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr,
         /* Sanity check */
         HDassert((size_t)(p - dblock->blk) == H5HF_MAN_ABS_DIRECT_OVERHEAD(hdr));
 
+#ifdef LATER
+        /* 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;               /* Filter mask for 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);
+
+            /* 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")
+HDfprintf(stderr, "%s: nbytes = %Zu, write_size = %Zu, write_buf = %p\n", FUNC, nbytes, write_size, write_buf);
+HDfprintf(stderr, "%s: dblock->size = %Zu, dblock->blk = %p\n", FUNC, dblock->size, dblock->blk);
+
+HDfprintf(stderr, "%s: I/O filters not supported yet!\n", FUNC);
+HGOTO_ERROR(H5E_HEAP, H5E_UNSUPPORTED, FAIL, "I/O filters not supported yet")
+        } /* end if */
+        else {
+#endif /* LATER */
+            write_buf = dblock->blk;
+            write_size = dblock->size;
+#ifdef LATER
+        } /* end else */
+#endif /* LATER */
+
 	/* Write the direct block */
-	if(H5F_block_write(f, H5FD_MEM_FHEAP_DBLOCK, addr, (size_t)dblock->size, dxpl_id, dblock->blk) < 0)
+	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")
 
+        /* Release the write buffer, if it was allocated */
+        if(write_buf != dblock->blk)
+            H5MM_xfree(write_buf);
+
 	dblock->cache_info.is_dirty = FALSE;
     } /* end if */
 
@@ -892,6 +1014,7 @@ H5HF_cache_dblock_size(const H5F_t UNUSED *f, const H5HF_direct_t *dblock, size_
 static H5HF_indirect_t *
 H5HF_cache_iblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, const void *_nrows, void *_par_info)
 {
+    H5HF_hdr_t          *hdr;           /* Shared fractal heap information */
     const unsigned      *nrows = (const unsigned *)_nrows;     /* # of rows in indirect block */
     H5HF_parent_t       *par_info = (H5HF_parent_t *)_par_info;     /* Shared parent information */
     H5HF_indirect_t	*iblock = NULL; /* Indirect block info */
@@ -917,9 +1040,12 @@ HDfprintf(stderr, "%s: Load indirect block, addr = %a\n", FUNC, addr);
 	HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed")
     HDmemset(&iblock->cache_info, 0, sizeof(H5AC_info_t));
 
+    /* Get the pointer to the shared heap header */
+    hdr = par_info->hdr;
+
     /* Share common heap information */
-    iblock->hdr = par_info->hdr;
-    if(H5HF_hdr_incr(iblock->hdr) < 0)
+    iblock->hdr = hdr;
+    if(H5HF_hdr_incr(hdr) < 0)
 	HGOTO_ERROR(H5E_HEAP, H5E_CANTINC, NULL, "can't increment reference count on shared heap header")
 
     /* Set block's internal information */
@@ -929,7 +1055,7 @@ HDfprintf(stderr, "%s: Load indirect block, addr = %a\n", FUNC, addr);
     iblock->nchildren = 0;
 
     /* Compute size of indirect block */
-    iblock->size = H5HF_MAN_INDIRECT_SIZE(iblock->hdr, iblock);
+    iblock->size = H5HF_MAN_INDIRECT_SIZE(hdr, iblock);
 
     /* Allocate buffer to decode block */
 /* XXX: Use free list factories? */
@@ -964,7 +1090,7 @@ HDfprintf(stderr, "%s: Load indirect block, addr = %a\n", FUNC, addr);
 
     /* Address of heap that owns this block */
     H5F_addr_decode(f, &p, &heap_addr);
-    if(H5F_addr_ne(heap_addr, iblock->hdr->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")
 
     /* Address of parent block */
@@ -980,31 +1106,59 @@ HDfprintf(stderr, "%s: Load indirect block, addr = %a\n", FUNC, addr);
     } /* end if */
     else {
         /* Set max. # of rows in this block */
-        iblock->max_rows = iblock->hdr->man_dtable.max_root_rows;
+        iblock->max_rows = hdr->man_dtable.max_root_rows;
     } /* end else */
 
     /* Offset of heap within the heap's address space */
-    UINT64DECODE_VAR(p, iblock->block_off, iblock->hdr->heap_off_size);
+    UINT64DECODE_VAR(p, iblock->block_off, hdr->heap_off_size);
 
-    /* Allocate & decode indirect block entry tables */
+    /* Allocate & decode child block entry tables */
     HDassert(iblock->nrows > 0);
-    if(NULL == (iblock->ents = H5FL_SEQ_MALLOC(H5HF_indirect_ent_t, (size_t)(iblock->nrows * iblock->hdr->man_dtable.cparam.width))))
+    if(NULL == (iblock->ents = H5FL_SEQ_MALLOC(H5HF_indirect_ent_t, (size_t)(iblock->nrows * hdr->man_dtable.cparam.width))))
 	HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed for direct entries")
-    for(u = 0; u < (iblock->nrows * iblock->hdr->man_dtable.cparam.width); u++) {
+    if(hdr->filter_len > 0) {
+        unsigned dir_rows;      /* Number of direct rows in this indirect block */
+
+        /* Compute the number of direct rows for this indirect block */
+        dir_rows = MIN(iblock->nrows, hdr->man_dtable.max_direct_rows);
+
+        /* Allocate indirect block filtered entry array */
+        if(NULL == (iblock->filt_ents = H5FL_SEQ_MALLOC(H5HF_indirect_filt_ent_t, (size_t)(dir_rows * hdr->man_dtable.cparam.width))))
+            HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed for block entries")
+    } /* end if */
+    else
+        iblock->filt_ents = NULL;
+    for(u = 0; u < (iblock->nrows * hdr->man_dtable.cparam.width); u++) {
         /* Decode child block address */
         H5F_addr_decode(f, &p, &(iblock->ents[u].addr));
 
+        /* Check for heap with I/O filters */
+        if(hdr->filter_len > 0) {
+            /* Sanity check */
+            HDassert(iblock->filt_ents);
+
+            /* 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(f, p, iblock->filt_ents[u].size);
+
+                /* 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));
+
+                /* I/O filter mask for filtered direct block */
+                UINT32DECODE(p, iblock->filt_ents[u].filter_mask);
+            } /* end if */
+        } /* end if */
+
         /* Count child blocks */
         if(H5F_addr_defined(iblock->ents[u].addr)) {
             iblock->nchildren++;
             iblock->max_child = u;
         } /* end if */
-
-#ifdef LATER
-        /* Decode direct & indirect blocks differently (later, when direct blocks can be compressed) */
-        if(u < (iblock->hdr->man_dtable.max_direct_rows * iblock->hdr->man_dtable.cparam.width))
-            UINT32DECODE_VAR(p, iblock->ents[u].free_space, iblock->hdr->man_dtable.max_dir_blk_off_size)
-#endif /* LATER */
 #ifdef QAK
 HDfprintf(stderr, "%s: iblock->ents[%Zu] = {%a}\n", FUNC, u, iblock->ents[u].addr);
 #endif /* QAK */
@@ -1113,6 +1267,31 @@ HDfprintf(stderr, "%s: iblock->ents[%Zu] = {%a}\n", FUNC, u, iblock->ents[u].add
             /* Encode child block address */
             H5F_addr_encode(f, &p, 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)) {
+#ifdef QAK
+HDfprintf(stderr, "%s: iblock->filt_ents[%Zu] = {%Zu, %x}\n", FUNC, u, iblock->filt_ents[u].size, iblock->filt_ents[u].filter_mask);
+#endif /* QAK */
+                    /* 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, p, iblock->filt_ents[u].size);
+
+                    /* I/O filter mask for filtered direct block */
+                    UINT32ENCODE(p, iblock->filt_ents[u].filter_mask);
+                } /* end if */
+            } /* end if */
+
 #ifndef NDEBUG
             /* Count child blocks */
             if(H5F_addr_defined(iblock->ents[u].addr)) {
@@ -1121,12 +1300,6 @@ HDfprintf(stderr, "%s: iblock->ents[%Zu] = {%a}\n", FUNC, u, iblock->ents[u].add
                     max_child = u;
             } /* end if */
 #endif /* NDEBUG */
-
-#ifdef LATER
-            /* Encode direct & indirect blocks differently (when direct blocks can be compressed) */
-            if(u < (hdr->man_dtable.max_direct_rows * hdr->man_dtable.cparam.width))
-                UINT32ENCODE_VAR(p, iblock->ents[u].free_space, hdr->man_dtable.max_dir_blk_off_size)
-#endif /* LATER */
         } /* end for */
 
         /* Sanity check */
@@ -1197,6 +1370,8 @@ HDfprintf(stderr, "%s: Destroying indirect block\n", FUNC);
     /* Release entry tables */
     if(iblock->ents)
         H5FL_SEQ_FREE(H5HF_indirect_ent_t, iblock->ents);
+    if(iblock->filt_ents)
+        H5FL_SEQ_FREE(H5HF_indirect_filt_ent_t, iblock->filt_ents);
 
     /* Free fractal heap indirect block info */
     H5FL_FREE(H5HF_indirect_t, iblock);
diff --git a/src/H5HFdbg.c b/src/H5HFdbg.c
index cfff2ca..b7d8b79 100644
--- a/src/H5HFdbg.c
+++ b/src/H5HFdbg.c
@@ -216,9 +216,6 @@ H5HF_hdr_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE *stream, int indent,
 	      "Objects stored in 'debugging' format:",
 	      hdr->debug_objs);
     HDfprintf(stream, "%*s%-*s %t\n", indent, "", fwidth,
-	      "I/O filters present:",
-	      hdr->have_io_filter);
-    HDfprintf(stream, "%*s%-*s %t\n", indent, "", fwidth,
 	      "'Write once' flag:",
 	      hdr->write_once);
     HDfprintf(stream, "%*s%-*s %t\n", indent, "", fwidth,
@@ -257,9 +254,22 @@ H5HF_hdr_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE *stream, int indent,
     HDfprintf(stream, "%*s%-*s %Hu\n", indent, "", fwidth,
 	      "Address of v2 B-tree for 'huge' objects:",
 	      hdr->huge_bt2_addr);
+    HDfprintf(stream, "%*s%-*s %Hu\n", indent, "", fwidth,
+	      "'Tiny' object space used:",
+	      hdr->tiny_size);
+    HDfprintf(stream, "%*s%-*s %Hu\n", indent, "", fwidth,
+	      "Number of 'tiny' objects in heap:",
+	      hdr->tiny_nobjs);
 
     HDfprintf(stream, "%*sManaged Objects Doubling-Table Info...\n", indent, "");
-    H5HF_dtable_debug(&hdr->man_dtable, stream, indent + 3, MAX(0, fwidth -3));
+    H5HF_dtable_debug(&hdr->man_dtable, stream, indent + 3, MAX(0, fwidth - 3));
+
+    /* Print information about I/O filters */
+    if(hdr->filter_len > 0) {
+        HDfprintf(stream, "%*sI/O filter Info...\n", indent, "");
+        H5O_debug_id(H5O_PLINE_ID, f, dxpl_id, &(hdr->pline), stream,
+                             indent + 3, MAX(0, fwidth - 3));
+    } /* end if */
 
 done:
     if(hdr && H5AC_unprotect(f, dxpl_id, H5AC_FHEAP_HDR, addr, hdr, H5AC__NO_FLAGS_SET) < 0)
diff --git a/src/H5HFhdr.c b/src/H5HFhdr.c
index a0af4b1..8376da4 100644
--- a/src/H5HFhdr.c
+++ b/src/H5HFhdr.c
@@ -232,7 +232,7 @@ done:
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HF_hdr_finish_init_pahse2
+ * Function:	H5HF_hdr_finish_init_phase2
  *
  * Purpose:	Second phase to finish initializing info in shared heap header
  *
@@ -281,7 +281,11 @@ HDfprintf(stderr, "%s: row_max_dblock_free[%Zu] = %Zu\n", FUNC, u, hdr->man_dtab
 
     /* Initialize the information for tracking 'huge' objects */
     if(H5HF_huge_init(hdr) < 0)
-        HGOTO_ERROR(H5E_HEAP, H5E_CANTINIT, FAIL, "can't informan for tracking huge objects")
+        HGOTO_ERROR(H5E_HEAP, H5E_CANTINIT, FAIL, "can't initialize info for tracking huge objects")
+
+    /* Initialize the information for tracking 'tiny' objects */
+    if(H5HF_tiny_init(hdr) < 0)
+        HGOTO_ERROR(H5E_HEAP, H5E_CANTINIT, FAIL, "can't initialize info for tracking tiny objects")
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
@@ -343,7 +347,6 @@ haddr_t
 H5HF_hdr_create(H5F_t *f, hid_t dxpl_id, const H5HF_create_t *cparam)
 {
     H5HF_hdr_t *hdr = NULL;     /* The new fractal heap header information */
-    haddr_t hdr_addr;           /* Heap header address */
     size_t dblock_overhead;     /* Direct block's overhead */
     haddr_t ret_value;          /* Return value */
 
@@ -388,12 +391,7 @@ H5HF_hdr_create(H5F_t *f, hid_t dxpl_id, const H5HF_create_t *cparam)
 	HGOTO_ERROR(H5E_HEAP, H5E_BADVALUE, HADDR_UNDEF, "max. heap size too large for file")
 #endif /* NDEBUG */
 
-    /* Allocate space for the header on disk */
-    if(HADDR_UNDEF == (hdr_addr = H5MF_alloc(f, H5FD_MEM_FHEAP_HDR, dxpl_id, (hsize_t)H5HF_HEADER_SIZE(hdr))))
-	HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, HADDR_UNDEF, "file allocation failed for fractal heap header")
-
     /* Set the creation parameters for the heap */
-    hdr->heap_addr = hdr_addr;
     hdr->max_man_size = cparam->max_man_size;
     HDmemcpy(&(hdr->man_dtable.cparam), &(cparam->managed), sizeof(H5HF_dtable_cparam_t));
 
@@ -410,9 +408,37 @@ H5HF_hdr_create(H5F_t *f, hid_t dxpl_id, const H5HF_create_t *cparam)
     hdr->dirty = TRUE;
 
     /* First phase of header final initialization */
+    /* (doesn't need ID length set up) */
     if(H5HF_hdr_finish_init_phase1(hdr) < 0)
 	HGOTO_ERROR(H5E_HEAP, H5E_CANTINIT, HADDR_UNDEF, "can't finish phase #1 of header final initialization")
 
+    /* Copy any I/O filter pipeline */
+    /* (This code is not in the "finish init phase" routines because those 
+     *  routines are also called from the cache 'load' callback, and the filter
+     *  length is already set in that case (its stored in the header on disk))
+     */
+    if(cparam->pline.nused > 0) {
+        /* Copy the I/O filter pipeline from the creation parameters to the header */
+        if(NULL == H5O_copy(H5O_PLINE_ID, &(cparam->pline), &(hdr->pline)))
+            HGOTO_ERROR(H5E_HEAP, H5E_CANTCOPY, HADDR_UNDEF, "can't copy I/O filter pipeline")
+
+        /* Compute the I/O filters' encoded size */
+        if(0 == (hdr->filter_len = H5O_raw_size(H5O_PLINE_ID, hdr->f, &(hdr->pline))))
+            HGOTO_ERROR(H5E_HEAP, H5E_CANTGETSIZE, HADDR_UNDEF, "can't get I/O filter pipeline size")
+#ifdef QAK
+HDfprintf(stderr, "%s: hdr->filter_len = %u\n", FUNC, hdr->filter_len);
+#endif /* QAK */
+
+        /* Compute size of header on disk */
+        hdr->heap_size = H5HF_HEADER_SIZE(hdr)  /* Base header size */
+            + hdr->sizeof_size                  /* Size of size for filtered root direct block */
+            + 4                                 /* Size of filter mask for filtered root direct block */
+            + hdr->filter_len;                  /* Size of encoded I/O filter info */
+    } /* end if */
+    else
+        /* Set size of header on disk */
+        hdr->heap_size = H5HF_HEADER_SIZE(hdr);
+
     /* Set the length of IDs in the heap */
     /* (This code is not in the "finish init phase" routines because those 
      *  routines are also called from the cache 'load' callback, and the ID
@@ -423,39 +449,55 @@ H5HF_hdr_create(H5F_t *f, hid_t dxpl_id, const H5HF_create_t *cparam)
             hdr->id_len = 1 + hdr->heap_off_size + hdr->heap_len_size;
             break;
 
-        case 1: /* Set the length of heap IDs to just enough to hold the file offset & length of 'huge' objects in the heap */
-            hdr->id_len = 1 + hdr->sizeof_size + hdr->sizeof_addr;
+        case 1: /* Set the length of heap IDs to just enough to hold the information needed to directly access 'huge' objects in the heap */
+            if(hdr->filter_len > 0)
+                hdr->id_len = 1         /* ID flags */
+                    + hdr->sizeof_addr  /* Address of filtered object */
+                    + hdr->sizeof_size  /* Length of filtered object */
+                    + 4                 /* Filter mask for filtered object */
+                    + hdr->sizeof_size; /* Size of de-filtered object in memory */
+            else
+                hdr->id_len = 1         /* ID flags */
+                    + hdr->sizeof_addr  /* Address of object */
+                    + hdr->sizeof_size; /* Length of object */
             break;
 
         default:    /* Use the requested size for the heap ID */
-/* XXX: Limit heap ID length to 4096 + 1, due to # of bits required to store
- *      length of 'tiny' objects (12 bits)
- */
-HDfprintf(stderr, "%s: Varying size of heap IDs not supported yet!\n", FUNC);
-HGOTO_ERROR(H5E_HEAP, H5E_UNSUPPORTED, HADDR_UNDEF, "varying size of heap IDs not supported yet")
+            /* Check boundaries */
+            if(cparam->id_len < (1 + hdr->heap_off_size + hdr->heap_len_size))
+                HGOTO_ERROR(H5E_HEAP, H5E_BADRANGE, HADDR_UNDEF, "ID length not large enough to hold object IDs")
+            else if(cparam->id_len > H5HF_MAX_ID_LEN)
+                HGOTO_ERROR(H5E_HEAP, H5E_BADRANGE, HADDR_UNDEF, "ID length too large to store tiny object lengths")
+
+            /* Use the requested size for the heap ID */
+            hdr->id_len = cparam->id_len;
             break;
     } /* end switch */
+#ifdef QAK
+HDfprintf(stderr, "%s: hdr->id_len = %Zu\n", FUNC, hdr->id_len);
+#endif /* QAK */
 
     /* Second phase of header final initialization */
+    /* (needs ID and filter lengths set up) */
     if(H5HF_hdr_finish_init_phase2(hdr) < 0)
 	HGOTO_ERROR(H5E_HEAP, H5E_CANTINIT, HADDR_UNDEF, "can't finish phase #2 of header final initialization")
 
-#ifdef QAK
-HDfprintf(stderr, "%s: hdr->id_len = %Zu\n", FUNC, hdr->id_len);
-#endif /* QAK */
-
     /* Extra checking for possible gap between max. direct block size minus
      * overhead and "huge" object size */
     dblock_overhead = H5HF_MAN_ABS_DIRECT_OVERHEAD(hdr);
     if((cparam->managed.max_direct_size - dblock_overhead) < cparam->max_man_size)
 	HGOTO_ERROR(H5E_HEAP, H5E_BADVALUE, HADDR_UNDEF, "max. direct block size not large enough to hold all managed blocks")
 
+    /* Allocate space for the header on disk */
+    if(HADDR_UNDEF == (hdr->heap_addr = H5MF_alloc(f, H5FD_MEM_FHEAP_HDR, dxpl_id, (hsize_t)hdr->heap_size)))
+	HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, HADDR_UNDEF, "file allocation failed for fractal heap header")
+
     /* Cache the new fractal heap header */
-    if(H5AC_set(f, dxpl_id, H5AC_FHEAP_HDR, hdr_addr, hdr, H5AC__NO_FLAGS_SET) < 0)
+    if(H5AC_set(f, dxpl_id, H5AC_FHEAP_HDR, hdr->heap_addr, hdr, H5AC__NO_FLAGS_SET) < 0)
 	HGOTO_ERROR(H5E_HEAP, H5E_CANTINIT, HADDR_UNDEF, "can't add fractal heap header to cache")
 
     /* Set address of heap header to return */
-    ret_value = hdr_addr;
+    ret_value = hdr->heap_addr;
 
 done:
     if(!H5F_addr_defined(ret_value))
diff --git a/src/H5HFhuge.c b/src/H5HFhuge.c
index 7a47dba..cc5b824 100644
--- a/src/H5HFhuge.c
+++ b/src/H5HFhuge.c
@@ -37,6 +37,7 @@
 #include "H5Eprivate.h"		/* Error handling		  	*/
 #include "H5HFpkg.h"		/* Fractal heaps			*/
 #include "H5MFprivate.h"	/* File memory management		*/
+#include "H5MMprivate.h"	/* Memory management			*/
 
 
 /****************/
@@ -63,20 +64,25 @@
 /* Local Prototypes */
 /********************/
 
-/* local v2 B-tree operations */
+/* Local v2 B-tree operations */
 static herr_t H5HF_huge_bt2_create(H5HF_hdr_t *hdr, hid_t dxpl_id);
 
 /* v2 B-tree function callbacks (in H5HFbtree2.c) */
-herr_t H5HF_huge_bt2_found(const void *nrecord, void *op_data);
-herr_t H5HF_huge_bt2_remove(const void *nrecord, void *op_data);
+herr_t H5HF_huge_bt2_indir_found(const void *nrecord, void *op_data);
+herr_t H5HF_huge_bt2_indir_remove(const void *nrecord, void *op_data);
+herr_t H5HF_huge_bt2_filt_indir_found(const void *nrecord, void *op_data);
+herr_t H5HF_huge_bt2_filt_indir_remove(const void *nrecord, void *op_data);
+herr_t H5HF_huge_bt2_dir_remove(const void *nrecord, void *op_data);
+herr_t H5HF_huge_bt2_filt_dir_found(const void *nrecord, void *op_data);
+herr_t H5HF_huge_bt2_filt_dir_remove(const void *nrecord, void *op_data);
+
+/* Local 'huge' object support routines */
+static hsize_t H5HF_huge_new_id(H5HF_hdr_t *hdr);
 
 /*********************/
 /* Package Variables */
 /*********************/
 
-/* The v2 B-tree class for tracking huge objects */
-H5_DLLVAR const H5B2_class_t H5HF_BTREE2[1];
-
 
 /*****************************/
 /* Library Private Variables */
@@ -104,6 +110,7 @@ H5_DLLVAR const H5B2_class_t H5HF_BTREE2[1];
 static herr_t
 H5HF_huge_bt2_create(H5HF_hdr_t *hdr, hid_t dxpl_id)
 {
+    const H5B2_class_t *bt2_class;      /* v2 B-tree class to use */
     size_t rrec_size;                   /* Size of 'raw' records on disk */
     herr_t ret_value = SUCCEED;         /* Return value */
 
@@ -115,13 +122,45 @@ H5HF_huge_bt2_create(H5HF_hdr_t *hdr, hid_t dxpl_id)
     HDassert(hdr);
 
     /* Compute the size of 'raw' records on disk */
-    if(hdr->huge_ids_direct)
-        rrec_size = hdr->sizeof_addr + hdr->sizeof_size;
-    else
-        rrec_size = hdr->sizeof_addr + hdr->sizeof_size + hdr->huge_id_size;
+    /* (Note: the size for huge IDs could be set to 'huge_id_size', instead
+     *  of 'sizeof_size', but that would make the v2 B-tree callback routines
+     *  depend on the heap header, which makes the v2 B-tree flush routines
+     *  difficult to write.  "Waste" an extra byte or for small heaps (where
+     *  the 'huge_id_size' is < 'sizeof_size' in order to make this easier -QAK)
+     */
+    if(hdr->huge_ids_direct) {
+        if(hdr->filter_len > 0) {
+            rrec_size = hdr->sizeof_addr    /* Address of object */
+                + hdr->sizeof_size          /* Length of object */
+                + 4                         /* Filter mask for filtered object */
+                + hdr->sizeof_size;         /* Size of de-filtered object in memory */
+            bt2_class = H5HF_BT2_FILT_DIR;
+        } /* end if */
+        else {
+            rrec_size = hdr->sizeof_addr    /* Address of object */
+                + hdr->sizeof_size;         /* Length of object */
+            bt2_class = H5HF_BT2_DIR;
+        } /* end else */
+    } /* end if */
+    else {
+        if (hdr->filter_len > 0) {
+            rrec_size = hdr->sizeof_addr    /* Address of filtered object */
+                + hdr->sizeof_size          /* Length of filtered object */
+                + 4                         /* Filter mask for filtered object */
+                + hdr->sizeof_size          /* Size of de-filtered object in memory */
+                + hdr->sizeof_size;         /* Unique ID for object */
+            bt2_class = H5HF_BT2_FILT_INDIR;
+        } /* end if */
+        else {
+            rrec_size = hdr->sizeof_addr    /* Address of object */
+                + hdr->sizeof_size          /* Length of object */
+                + hdr->sizeof_size;         /* Unique ID for object */
+            bt2_class = H5HF_BT2_INDIR;
+        } /* end else */
+    } /* end else */
 
     /* Create v2 B-tree for tracking 'huge' objects */
-    if(H5B2_create(hdr->f, dxpl_id, &hdr->huge_bt2_class, (size_t)H5HF_HUGE_BT2_NODE_SIZE, rrec_size,
+    if(H5B2_create(hdr->f, dxpl_id, bt2_class, (size_t)H5HF_HUGE_BT2_NODE_SIZE, rrec_size,
             H5HF_HUGE_BT2_SPLIT_PERC, H5HF_HUGE_BT2_MERGE_PERC, &hdr->huge_bt2_addr/*out*/) < 0)
         HGOTO_ERROR(H5E_HEAP, H5E_CANTCREATE, FAIL, "can't create v2 B-tree for tracking 'huge' heap objects")
 
@@ -156,22 +195,38 @@ H5HF_huge_init(H5HF_hdr_t *hdr)
     /* Compute information about 'huge' objects for the heap */
 
     /* Check if we can completely hold the 'huge' object's offset & length in
-     *  the file in the heap ID (which will speed up accessing it)
+     *  the file in the heap ID (which will speed up accessing it) and we don't
+     *  have any I/O pipeline filters.
      */
 #ifdef QAK
 HDfprintf(stderr, "%s: hdr->id_len = %u\n", "H5HF_huge_init", (unsigned)hdr->id_len);
+HDfprintf(stderr, "%s: hdr->filter_len = %u\n", "H5HF_huge_init", (unsigned)hdr->filter_len);
 #endif /* QAK */
-    if((hdr->sizeof_addr + hdr->sizeof_size) <= (hdr->id_len - 1)) {
-        /* Indicate that v2 B-tree doesn't have to be used to locate object */
-        hdr->huge_ids_direct = TRUE;
-
-        /* Set the size of 'huge' object IDs */
-        hdr->huge_id_size = hdr->sizeof_addr + hdr->sizeof_size;
+    if(hdr->filter_len > 0) {
+        if((hdr->id_len - 1) >= (hdr->sizeof_addr + hdr->sizeof_size + 4 + hdr->sizeof_size)) {
+            /* Indicate that v2 B-tree doesn't have to be used to locate object */
+            hdr->huge_ids_direct = TRUE;
+
+            /* Set the size of 'huge' object IDs */
+            hdr->huge_id_size = hdr->sizeof_addr + hdr->sizeof_size + hdr->sizeof_size;
+        } /* end if */
+        else
+            /* Indicate that v2 B-tree must be used to access object */
+            hdr->huge_ids_direct = FALSE;
     } /* end if */
     else {
-        /* Indicate that v2 B-tree must be used to locate object */
-        hdr->huge_ids_direct = FALSE;
-
+        if((hdr->sizeof_addr + hdr->sizeof_size) <= (hdr->id_len - 1)) {
+            /* Indicate that v2 B-tree doesn't have to be used to locate object */
+            hdr->huge_ids_direct = TRUE;
+
+            /* Set the size of 'huge' object IDs */
+            hdr->huge_id_size = hdr->sizeof_addr + hdr->sizeof_size;
+        } /* end if */
+        else
+            /* Indicate that v2 B-tree must be used to locate object */
+            hdr->huge_ids_direct = FALSE;
+    } /* end else */
+    if(!hdr->huge_ids_direct) {
         /* Set the size and maximum value of 'huge' object ID */
         if((hdr->id_len - 1) < sizeof(hsize_t)) {
             hdr->huge_id_size = hdr->id_len - 1;
@@ -181,28 +236,65 @@ HDfprintf(stderr, "%s: hdr->id_len = %u\n", "H5HF_huge_init", (unsigned)hdr->id_
             hdr->huge_id_size = sizeof(hsize_t);
             hdr->huge_max_id = HSIZET_MAX;
         } /* end else */
-    } /* end else */
+    } /* end if */
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5HF_huge_init() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_huge_new_id
+ *
+ * Purpose:	Determine a new ID for an indirectly accessed 'huge' object
+ *              (either filtered or not)
+ *
+ * Return:	SUCCEED/FAIL
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@hdfgroup.org
+ *		Aug 15 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+static hsize_t
+H5HF_huge_new_id(H5HF_hdr_t *hdr)
+{
+    hsize_t new_id;             /* New object's ID */
+    hsize_t ret_value;          /* Return value */
 
+    FUNC_ENTER_NOAPI_NOINIT(H5HF_huge_new_id)
 
-    /* Set up the v2 B-tree for tracking 'huge' objects in the heap */
+    /*
+     * Check arguments.
+     */
+    HDassert(hdr);
 
-    /* Copy the standard v2 B-tree class */
-    HDmemcpy(&hdr->huge_bt2_class, H5HF_BTREE2, sizeof(H5B2_class_t));
+    /* Check for wrapping around 'huge' object ID space */
+    if(hdr->huge_ids_wrapped)
+        /* Fail for now - eventually should iterate through v2 B-tree, looking for available ID */
+        HGOTO_ERROR(H5E_HEAP, H5E_UNSUPPORTED, 0, "wrapping 'huge' object IDs not supported yet")
+    else {
+        /* Get new 'huge' object ID to use for object */
+        /* (avoids using ID 0) */
+        new_id = ++hdr->huge_next_id;
 
-    /* Set the native record size for the v2 B-tree */
-    hdr->huge_bt2_class.nrec_size = sizeof(H5HF_huge_bt2_rec_t);
+        /* Check for wrapping 'huge' object IDs around */
+        if(hdr->huge_next_id == hdr->huge_max_id)
+            hdr->huge_ids_wrapped = TRUE;
+    } /* end else */
 
-    /* Set v2 B-tree class's "class private" pointer to the heap header */
-    hdr->huge_bt2_class.cls_private = hdr;
+    /* Set return value */
+    ret_value = new_id;
 
-    FUNC_LEAVE_NOAPI(SUCCEED)
-} /* end H5HF_huge_init() */
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5HF_huge_new_id() */
 
 
 /*-------------------------------------------------------------------------
  * Function:	H5HF_huge_insert
  *
- * Purpose:	Insert a huge object into the file and track it
+ * Purpose:	Insert a 'huge' object into the file and track it
  *
  * Return:	SUCCEED/FAIL
  *
@@ -213,12 +305,14 @@ HDfprintf(stderr, "%s: hdr->id_len = %u\n", "H5HF_huge_init", (unsigned)hdr->id_
  *-------------------------------------------------------------------------
  */
 herr_t
-H5HF_huge_insert(H5HF_hdr_t *hdr, hid_t dxpl_id, size_t obj_size, const void *obj,
+H5HF_huge_insert(H5HF_hdr_t *hdr, hid_t dxpl_id, size_t obj_size, void *obj,
     void *_id)
 {
-    H5HF_huge_bt2_rec_t obj_rec;        /* Record for tracking object */
     uint8_t *id = (uint8_t *)_id;       /* Pointer to ID buffer */
     haddr_t obj_addr;                   /* Address of object in the file */
+    void *write_buf;                    /* Pointer to buffer to write */
+    size_t write_size;                  /* Size of [possibly filtered] object written to file */
+    unsigned filter_mask = 0;           /* Filter mask for object (only used for filtered objects) */
     herr_t ret_value = SUCCEED;         /* Return value */
 
     FUNC_ENTER_NOAPI_NOINIT(H5HF_huge_insert)
@@ -239,54 +333,142 @@ HDfprintf(stderr, "%s: obj_size = %Zu\n", FUNC, obj_size);
         if(H5HF_huge_bt2_create(hdr, dxpl_id) < 0)
             HGOTO_ERROR(H5E_HEAP, H5E_CANTCREATE, FAIL, "can't create v2 B-tree for tracking 'huge' heap objects")
 
+    /* Check for I/O pipeline filter on heap */
+    if(hdr->filter_len > 0) {
+        H5Z_cb_t filter_cb = {NULL, NULL};  /* Filter callback structure */
+        size_t nbytes;                      /* Number of bytes used */
+
+        /* Allocate buffer to perform I/O filtering on */
+        write_size = obj_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, obj, write_size);
+
+        /* Push direct block data through I/O filter pipeline */
+        nbytes = write_size;
+        if(H5Z_pipeline(&(hdr->pline), 0, &filter_mask, H5Z_NO_EDC,
+                 filter_cb, &nbytes, &write_size, &write_buf) < 0)
+            HGOTO_ERROR(H5E_HEAP, H5E_CANTFILTER, FAIL, "output pipeline failed")
+#ifdef QAK
+HDfprintf(stderr, "%s: nbytes = %Zu, write_size = %Zu, write_buf = %p\n", FUNC, nbytes, write_size, write_buf);
+HDfprintf(stderr, "%s: obj_size = %Zu, obj = %p\n", FUNC, obj_size, obj);
+#endif /* QAK */
+
+        /* Update size of object on disk */
+        write_size = nbytes;
+    } /* end if */
+    else {
+        write_buf = obj;
+        write_size = obj_size;
+    } /* end else */
+
     /* Allocate space in the file for storing the 'huge' object */
-    if(HADDR_UNDEF == (obj_addr = H5MF_alloc(hdr->f, H5FD_MEM_FHEAP_HUGE_OBJ, dxpl_id, (hsize_t)obj_size)))
+    if(HADDR_UNDEF == (obj_addr = H5MF_alloc(hdr->f, H5FD_MEM_FHEAP_HUGE_OBJ, dxpl_id, (hsize_t)write_size)))
         HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, FAIL, "file allocation failed for fractal heap huge object")
 
     /* Write the object's data to disk */
-    if(H5F_block_write(hdr->f, H5FD_MEM_FHEAP_HUGE_OBJ, obj_addr, obj_size, dxpl_id, obj) < 0)
+    if(H5F_block_write(hdr->f, H5FD_MEM_FHEAP_HUGE_OBJ, obj_addr, write_size, dxpl_id, write_buf) < 0)
         HGOTO_ERROR(H5E_HEAP, H5E_WRITEERROR, FAIL, "writing 'huge' object to file failed")
 
-    /* Initialize shared part of record for tracking object in v2 B-tree */
-    obj_rec.addr = obj_addr;
-    obj_rec.len = obj_size;
+    /* Release buffer for writing, if we had one */
+    if(write_buf != obj) {
+        HDassert(hdr->filter_len > 0);
+        H5MM_xfree(write_buf);
+    } /* end if */
+
+    /* Perform different actions for directly & indirectly accessed 'huge' objects */
+    if(hdr->huge_ids_direct) {
+        if(hdr->filter_len > 0) {
+            H5HF_huge_bt2_filt_dir_rec_t obj_rec;        /* Record for tracking object */
+
+            /* Initialize record for tracking object in v2 B-tree */
+            obj_rec.addr = obj_addr;
+            obj_rec.len = write_size;
+            obj_rec.filter_mask = filter_mask;
+            obj_rec.obj_size = obj_size;
+#ifdef QAK
+HDfprintf(stderr, "%s: obj_rec = {%a, %Hu, %x, %Hu}\n", FUNC, obj_rec.addr, obj_rec.len, obj_rec.filter_mask, obj_rec.obj_size);
+#endif /* QAK */
 
-    /* If the 'huge' object will be indirectly accessed, through the v2 B-tree,
-     *  create an ID for it, otherwise put a zero in for ID
-     */
-    if(hdr->huge_ids_direct)
-        obj_rec.id = 0;
-    else {
-        /* Check for wrapping around 'huge' object ID space */
-        if(hdr->huge_ids_wrapped)
-            /* Fail for now - eventually should iterate through v2 B-tree, looking for available ID */
-            HGOTO_ERROR(H5E_HEAP, H5E_UNSUPPORTED, FAIL, "wrapping 'huge' object IDs not supported yet")
+            /* Insert record for object in v2 B-tree */
+            if(H5B2_insert(hdr->f, dxpl_id, H5HF_BT2_FILT_DIR, hdr->huge_bt2_addr, &obj_rec) < 0)
+                HGOTO_ERROR(H5E_HEAP, H5E_CANTINSERT, FAIL, "couldn't insert object tracking record in v2 B-tree")
+
+            /* Encode ID for user */
+            *id++ = H5HF_ID_VERS_CURR | H5HF_ID_TYPE_HUGE;
+            H5F_addr_encode(hdr->f, &id, obj_addr);
+            H5F_ENCODE_LENGTH(hdr->f, id, (hsize_t)write_size);
+            UINT32ENCODE(id, filter_mask);
+            H5F_ENCODE_LENGTH(hdr->f, id, (hsize_t)obj_size);
+        } /* end if */
         else {
-            /* Get new 'huge' object ID to use for object */
-            /* (avoid using ID 0) */
-            obj_rec.id = ++hdr->huge_next_id;
+            H5HF_huge_bt2_dir_rec_t obj_rec;        /* Record for tracking object */
 
-            /* Check for wrapping 'huge' object IDs around */
-            if(hdr->huge_next_id == hdr->huge_max_id)
-                hdr->huge_ids_wrapped = TRUE;
-        } /* end else */
-    } /* end else */
+            /* Initialize record for tracking object in v2 B-tree */
+            obj_rec.addr = obj_addr;
+            obj_rec.len = write_size;
 #ifdef QAK
-HDfprintf(stderr, "%s: obj_rec = {%a, %Hu, %Hu}\n", FUNC, obj_rec.addr, obj_rec.len, obj_rec.id);
+HDfprintf(stderr, "%s: obj_rec = {%a, %Hu}\n", FUNC, obj_rec.addr, obj_rec.len);
 #endif /* QAK */
 
-    /* Insert record for object in v2 B-tree */
-    if(H5B2_insert(hdr->f, dxpl_id, &hdr->huge_bt2_class, hdr->huge_bt2_addr, &obj_rec) < 0)
-        HGOTO_ERROR(H5E_HEAP, H5E_CANTINSERT, FAIL, "couldn't insert object tracking record in v2 B-tree")
+            /* Insert record for object in v2 B-tree */
+            if(H5B2_insert(hdr->f, dxpl_id, H5HF_BT2_DIR, hdr->huge_bt2_addr, &obj_rec) < 0)
+                HGOTO_ERROR(H5E_HEAP, H5E_CANTINSERT, FAIL, "couldn't insert object tracking record in v2 B-tree")
 
-    /* Encode ID for user */
-    *id++ = H5HF_ID_VERS_CURR | H5HF_ID_TYPE_HUGE;
-    if(hdr->huge_ids_direct) {
-        H5F_addr_encode(hdr->f, &id, obj_addr);
-        H5F_ENCODE_LENGTH(hdr->f, id, (hsize_t)obj_size);
+            /* Encode ID for user */
+            *id++ = H5HF_ID_VERS_CURR | H5HF_ID_TYPE_HUGE;
+            H5F_addr_encode(hdr->f, &id, obj_addr);
+            H5F_ENCODE_LENGTH(hdr->f, id, (hsize_t)write_size);
+        } /* end if */
     } /* end if */
-    else
-        UINT64ENCODE_VAR(id, obj_rec.id, hdr->huge_id_size)
+    else {
+        H5HF_huge_bt2_filt_indir_rec_t filt_indir_rec;      /* Record for tracking filtered object */
+        H5HF_huge_bt2_indir_rec_t indir_rec;    /* Record for tracking non-filtered object */
+        const H5B2_class_t *bt2_class;          /* v2 B-tree class to use */
+        void *ins_rec;          /* Pointer to record to insert */
+        hsize_t new_id;         /* New ID for object */
+
+        /* Get new ID for object */
+        if(0 == (new_id = H5HF_huge_new_id(hdr)))
+            HGOTO_ERROR(H5E_HEAP, H5E_CANTINIT, FAIL, "can't generate new ID for object")
+
+        if(hdr->filter_len > 0) {
+            /* Initialize record for object in v2 B-tree */
+            filt_indir_rec.addr = obj_addr;
+            filt_indir_rec.len = write_size;
+            filt_indir_rec.filter_mask = filter_mask;
+            filt_indir_rec.obj_size = obj_size;
+            filt_indir_rec.id = new_id;
+#ifdef QAK
+HDfprintf(stderr, "%s: filt_indir_rec = {%a, %Hu, %x, %Hu, %Hu}\n", FUNC, filt_indir_rec.addr, filt_indir_rec.len, filt_indir_rec.filter_mask, filt_indir_rec.obj_size, filt_indir_rec.id);
+#endif /* QAK */
+
+            /* Set pointer to record to insert */
+            ins_rec = &filt_indir_rec;
+            bt2_class = H5HF_BT2_FILT_INDIR;
+        } /* end if */
+        else {
+            /* Initialize record for object in v2 B-tree */
+            indir_rec.addr = obj_addr;
+            indir_rec.len = write_size;
+            indir_rec.id = new_id;
+#ifdef QAK
+HDfprintf(stderr, "%s: indir_rec = {%a, %Hu, %Hu}\n", FUNC, indir_rec.addr, indir_rec.len, indir_rec.id);
+#endif /* QAK */
+
+            /* Set pointer to record to insert */
+            ins_rec = &indir_rec;
+            bt2_class = H5HF_BT2_INDIR;
+        } /* end else */
+
+        /* Insert record for tracking object in v2 B-tree */
+        if(H5B2_insert(hdr->f, dxpl_id, bt2_class, hdr->huge_bt2_addr, ins_rec) < 0)
+            HGOTO_ERROR(H5E_HEAP, H5E_CANTINSERT, FAIL, "couldn't insert object tracking record in v2 B-tree")
+
+        /* Encode ID for user */
+        *id++ = H5HF_ID_VERS_CURR | H5HF_ID_TYPE_HUGE;
+        UINT64ENCODE_VAR(id, new_id, hdr->huge_id_size)
+    } /* end else */
 
     /* Update statistics about heap */
     hdr->huge_size += obj_size;
@@ -320,7 +502,7 @@ H5HF_huge_get_obj_len(H5HF_hdr_t *hdr, hid_t dxpl_id, const uint8_t *id,
 {
     herr_t ret_value = SUCCEED;         /* Return value */
 
-    FUNC_ENTER_NOAPI(H5HF_huge_get_obj_len, FAIL)
+    FUNC_ENTER_NOAPI_NOINIT(H5HF_huge_get_obj_len)
 
     /*
      * Check arguments.
@@ -330,28 +512,57 @@ H5HF_huge_get_obj_len(H5HF_hdr_t *hdr, hid_t dxpl_id, const uint8_t *id,
     HDassert(id);
     HDassert(obj_len_p);
 
+    /* Skip over the flag byte */
+    id++;
+
     /* Check if 'huge' object ID encodes address & length directly */
     if(hdr->huge_ids_direct) {
-        /* Skip over object offset in file */
-        id += hdr->sizeof_addr;
+        if(hdr->filter_len > 0) {
+            /* Skip over filtered object info */
+            id += hdr->sizeof_addr + hdr->sizeof_size + 4;
+
+            /* Retrieve the object's length */
+            H5F_DECODE_LENGTH(hdr->f, id, *obj_len_p);
+        } /* end if */
+        else {
+            /* Skip over object offset in file */
+            id += hdr->sizeof_addr;
 
-        /* Retrieve the object's length */
-        H5F_DECODE_LENGTH(hdr->f, id, *obj_len_p);
+            /* Retrieve the object's length */
+            H5F_DECODE_LENGTH(hdr->f, id, *obj_len_p);
+        } /* end else */
     } /* end if */
     else {
-        H5HF_huge_bt2_rec_t found_rec;  /* Record found from tracking object */
-        H5HF_huge_bt2_rec_t search_rec; /* Record for searching for object */
+        if(hdr->filter_len > 0) {
+            H5HF_huge_bt2_filt_indir_rec_t found_rec;  /* Record found from tracking object */
+            H5HF_huge_bt2_filt_indir_rec_t search_rec; /* Record for searching for object */
+
+            /* Get ID for looking up 'huge' object in v2 B-tree */
+            UINT64DECODE_VAR(id, search_rec.id, hdr->huge_id_size)
+
+            /* Look up object in v2 B-tree */
+            if(H5B2_find(hdr->f, dxpl_id, H5HF_BT2_FILT_INDIR, hdr->huge_bt2_addr,
+                        &search_rec, H5HF_huge_bt2_filt_indir_found, &found_rec) < 0)
+                HGOTO_ERROR(H5E_HEAP, H5E_NOTFOUND, FAIL, "can't find object in B-tree")
+
+            /* Retrieve the object's length */
+            *obj_len_p = (size_t)found_rec.obj_size;
+        } /* end if */
+        else {
+            H5HF_huge_bt2_indir_rec_t found_rec;  /* Record found from tracking object */
+            H5HF_huge_bt2_indir_rec_t search_rec; /* Record for searching for object */
 
-        /* Get ID for looking up 'huge' object in v2 B-tree */
-        UINT64DECODE_VAR(id, search_rec.id, hdr->huge_id_size)
+            /* Get ID for looking up 'huge' object in v2 B-tree */
+            UINT64DECODE_VAR(id, search_rec.id, hdr->huge_id_size)
 
-        /* Look up object in v2 B-tree */
-        if(H5B2_find(hdr->f, dxpl_id, &hdr->huge_bt2_class, hdr->huge_bt2_addr,
-                    &search_rec, H5HF_huge_bt2_found, &found_rec) < 0)
-            HGOTO_ERROR(H5E_HEAP, H5E_NOTFOUND, FAIL, "can't find object in B-tree")
+            /* Look up object in v2 B-tree */
+            if(H5B2_find(hdr->f, dxpl_id, H5HF_BT2_INDIR, hdr->huge_bt2_addr,
+                        &search_rec, H5HF_huge_bt2_indir_found, &found_rec) < 0)
+                HGOTO_ERROR(H5E_HEAP, H5E_NOTFOUND, FAIL, "can't find object in B-tree")
 
-        /* Retrieve the object's length */
-        *obj_len_p = (size_t)found_rec.len;
+            /* Retrieve the object's length */
+            *obj_len_p = (size_t)found_rec.len;
+        } /* end else */
     } /* end else */
 
 done:
@@ -375,8 +586,10 @@ done:
 herr_t
 H5HF_huge_read(H5HF_hdr_t *hdr, hid_t dxpl_id, const uint8_t *id, void *obj)
 {
+    void *read_buf;                     /* Pointer to buffer for reading */
     haddr_t obj_addr;                   /* Object's address in the file */
     hsize_t obj_size = 0;               /* Object's size in the file */
+    unsigned filter_mask = 0;           /* Filter mask for object (only used for filtered objects) */
     herr_t ret_value = SUCCEED;         /* Return value */
 
     FUNC_ENTER_NOAPI_NOINIT(H5HF_huge_read)
@@ -388,33 +601,85 @@ H5HF_huge_read(H5HF_hdr_t *hdr, hid_t dxpl_id, const uint8_t *id, void *obj)
     HDassert(id);
     HDassert(obj);
 
+    /* Skip over the flag byte */
+    id++;
+
     /* Check for 'huge' object ID that encodes address & length directly */
     if(hdr->huge_ids_direct) {
-        /* Retrieve the object's address and length */
+        /* Retrieve the object's address and length (common) */
         H5F_addr_decode(hdr->f, &id, &obj_addr);
         H5F_DECODE_LENGTH(hdr->f, id, obj_size);
+
+        /* Retrieve extra information needed for filtered objects */
+        if(hdr->filter_len > 0)
+            UINT32DECODE(id, filter_mask);
     } /* end if */
     else {
-        H5HF_huge_bt2_rec_t found_rec;  /* Record found from tracking object */
-        H5HF_huge_bt2_rec_t search_rec; /* Record for searching for object */
+        if(hdr->filter_len > 0) {
+            H5HF_huge_bt2_filt_indir_rec_t found_rec;  /* Record found from tracking object */
+            H5HF_huge_bt2_filt_indir_rec_t search_rec; /* Record for searching for object */
+
+            /* Get ID for looking up 'huge' object in v2 B-tree */
+            UINT64DECODE_VAR(id, search_rec.id, hdr->huge_id_size)
+
+            /* Look up object in v2 B-tree */
+            if(H5B2_find(hdr->f, dxpl_id, H5HF_BT2_FILT_INDIR, hdr->huge_bt2_addr,
+                        &search_rec, H5HF_huge_bt2_filt_indir_found, &found_rec) < 0)
+                HGOTO_ERROR(H5E_HEAP, H5E_NOTFOUND, FAIL, "can't find object in B-tree")
+
+            /* Retrieve the object's address & length */
+            obj_addr = found_rec.addr;
+            obj_size = found_rec.len;
+            filter_mask = found_rec.filter_mask;
+        } /* end if */
+        else {
+            H5HF_huge_bt2_indir_rec_t found_rec;  /* Record found from tracking object */
+            H5HF_huge_bt2_indir_rec_t search_rec; /* Record for searching for object */
 
-        /* Get ID for looking up 'huge' object in v2 B-tree */
-        UINT64DECODE_VAR(id, search_rec.id, hdr->huge_id_size)
+            /* Get ID for looking up 'huge' object in v2 B-tree */
+            UINT64DECODE_VAR(id, search_rec.id, hdr->huge_id_size)
 
-        /* Look up object in v2 B-tree */
-        if(H5B2_find(hdr->f, dxpl_id, &hdr->huge_bt2_class, hdr->huge_bt2_addr,
-                    &search_rec, H5HF_huge_bt2_found, &found_rec) < 0)
-            HGOTO_ERROR(H5E_HEAP, H5E_NOTFOUND, FAIL, "can't find object in B-tree")
+            /* Look up object in v2 B-tree */
+            if(H5B2_find(hdr->f, dxpl_id, H5HF_BT2_INDIR, hdr->huge_bt2_addr,
+                        &search_rec, H5HF_huge_bt2_indir_found, &found_rec) < 0)
+                HGOTO_ERROR(H5E_HEAP, H5E_NOTFOUND, FAIL, "can't find object in B-tree")
 
-        /* Retrieve the object's address & length */
-        obj_addr = found_rec.addr;
-        obj_size = found_rec.len;
+            /* Retrieve the object's address & length */
+            obj_addr = found_rec.addr;
+            obj_size = found_rec.len;
+        } /* end else */
     } /* end else */
 
-    /* Read the object's data from the file */
-    if (H5F_block_read(hdr->f, H5FD_MEM_FHEAP_HUGE_OBJ, obj_addr, (size_t)obj_size, dxpl_id, obj) < 0)
+    /* Set up buffer for reading */
+    if(hdr->filter_len > 0) {
+        if(NULL == (read_buf = H5MM_malloc((size_t)obj_size)))
+            HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, FAIL, "memory allocation failed for pipeline buffer")
+    } /* end if */
+    else
+        read_buf = obj;
+
+    /* Read the object's (possibly filtered) data from the file */
+    if(H5F_block_read(hdr->f, H5FD_MEM_FHEAP_HUGE_OBJ, obj_addr, (size_t)obj_size, dxpl_id, read_buf) < 0)
         HGOTO_ERROR(H5E_HEAP, H5E_READERROR, FAIL, "can't read 'huge' object's data from the file")
 
+    /* Check for I/O pipeline filter on heap */
+    if(hdr->filter_len > 0) {
+        H5Z_cb_t filter_cb = {NULL, NULL};  /* Filter callback structure */
+        size_t read_size;                   /* Object's size in the file */
+        size_t nbytes;                      /* Number of bytes used */
+
+        /* De-filter the object */
+        read_size = nbytes = obj_size;
+        if(H5Z_pipeline(&(hdr->pline), H5Z_FLAG_REVERSE, &filter_mask, H5Z_NO_EDC, filter_cb, &nbytes, &read_size, &read_buf) < 0)
+            HGOTO_ERROR(H5E_HEAP, H5E_CANTFILTER, FAIL, "input filter failed")
+
+        /* Copy object to user's buffer */
+        HDmemcpy(obj, read_buf, nbytes);
+
+        /* Release read buffer */
+        H5MM_xfree(read_buf);
+    } /* end if */
+
 done:
     FUNC_LEAVE_NOAPI(ret_value)
 } /* end H5HF_huge_read() */
@@ -436,7 +701,6 @@ done:
 herr_t
 H5HF_huge_remove(H5HF_hdr_t *hdr, hid_t dxpl_id, const uint8_t *id)
 {
-    H5HF_huge_bt2_rec_t search_rec;     /* Record for searching for object */
     H5HF_huge_remove_ud1_t udata;       /* User callback data for v2 B-tree remove call */
     herr_t ret_value = SUCCEED;         /* Return value */
 
@@ -448,26 +712,70 @@ H5HF_huge_remove(H5HF_hdr_t *hdr, hid_t dxpl_id, const uint8_t *id)
     HDassert(hdr);
     HDassert(id);
 
+    /* Skip over the flag byte */
+    id++;
+
+    /* Set up the common callback info */
+    udata.hdr = hdr;
+    udata.dxpl_id = dxpl_id;
+
     /* Check for 'huge' object ID that encodes address & length directly */
     if(hdr->huge_ids_direct) {
-        /* Retrieve the object's address and length */
-        /* (used as key in v2 B-tree record) */
-        H5F_addr_decode(hdr->f, &id, &search_rec.addr);
-        H5F_DECODE_LENGTH(hdr->f, id, search_rec.len);
+        if(hdr->filter_len > 0) {
+            H5HF_huge_bt2_filt_dir_rec_t search_rec;     /* Record for searching for object */
+
+            /* Retrieve the object's address and length */
+            /* (used as key in v2 B-tree record) */
+            H5F_addr_decode(hdr->f, &id, &search_rec.addr);
+            H5F_DECODE_LENGTH(hdr->f, id, search_rec.len);
+
+            /* Remove the record for tracking the 'huge' object from the v2 B-tree */
+            /* (space in the file for the object is freed in the 'remove' callback) */
+            if(H5B2_remove(hdr->f, dxpl_id, H5HF_BT2_FILT_DIR, hdr->huge_bt2_addr,
+                        &search_rec, H5HF_huge_bt2_filt_dir_remove, &udata) < 0)
+                HGOTO_ERROR(H5E_HEAP, H5E_CANTREMOVE, FAIL, "can't remove object from B-tree")
+        } /* end if */
+        else {
+            H5HF_huge_bt2_dir_rec_t search_rec;     /* Record for searching for object */
+
+            /* Retrieve the object's address and length */
+            /* (used as key in v2 B-tree record) */
+            H5F_addr_decode(hdr->f, &id, &search_rec.addr);
+            H5F_DECODE_LENGTH(hdr->f, id, search_rec.len);
+
+            /* Remove the record for tracking the 'huge' object from the v2 B-tree */
+            /* (space in the file for the object is freed in the 'remove' callback) */
+            if(H5B2_remove(hdr->f, dxpl_id, H5HF_BT2_DIR, hdr->huge_bt2_addr,
+                        &search_rec, H5HF_huge_bt2_dir_remove, &udata) < 0)
+                HGOTO_ERROR(H5E_HEAP, H5E_CANTREMOVE, FAIL, "can't remove object from B-tree")
+        } /* end else */
     } /* end if */
-    else
-        /* Get ID for looking up 'huge' object in v2 B-tree */
-        UINT64DECODE_VAR(id, search_rec.id, hdr->huge_id_size)
+    else {
+        if(hdr->filter_len > 0) {
+            H5HF_huge_bt2_filt_indir_rec_t search_rec;     /* Record for searching for object */
+
+            /* Get ID for looking up 'huge' object in v2 B-tree */
+            UINT64DECODE_VAR(id, search_rec.id, hdr->huge_id_size)
+
+            /* Remove the record for tracking the 'huge' object from the v2 B-tree */
+            /* (space in the file for the object is freed in the 'remove' callback) */
+            if(H5B2_remove(hdr->f, dxpl_id, H5HF_BT2_FILT_INDIR, hdr->huge_bt2_addr,
+                        &search_rec, H5HF_huge_bt2_filt_indir_remove, &udata) < 0)
+                HGOTO_ERROR(H5E_HEAP, H5E_CANTREMOVE, FAIL, "can't remove object from B-tree")
+        } /* end if */
+        else {
+            H5HF_huge_bt2_indir_rec_t search_rec;     /* Record for searching for object */
 
-    /* Set up the callback info */
-    udata.hdr = hdr;
-    udata.dxpl_id = dxpl_id;
+            /* Get ID for looking up 'huge' object in v2 B-tree */
+            UINT64DECODE_VAR(id, search_rec.id, hdr->huge_id_size)
 
-    /* Remove the record for tracking the 'huge' object from the v2 B-tree */
-    /* (space in the file for the object is freed in the 'remove' callback) */
-    if(H5B2_remove(hdr->f, dxpl_id, &hdr->huge_bt2_class, hdr->huge_bt2_addr,
-                &search_rec, H5HF_huge_bt2_remove, &udata) < 0)
-        HGOTO_ERROR(H5E_HEAP, H5E_CANTREMOVE, FAIL, "can't remove object from B-tree")
+            /* Remove the record for tracking the 'huge' object from the v2 B-tree */
+            /* (space in the file for the object is freed in the 'remove' callback) */
+            if(H5B2_remove(hdr->f, dxpl_id, H5HF_BT2_INDIR, hdr->huge_bt2_addr,
+                        &search_rec, H5HF_huge_bt2_indir_remove, &udata) < 0)
+                HGOTO_ERROR(H5E_HEAP, H5E_CANTREMOVE, FAIL, "can't remove object from B-tree")
+        } /* end else */
+    } /* end else */
 
     /* Update statistics about heap */
     hdr->huge_size -= udata.obj_len;
@@ -515,7 +823,8 @@ H5HF_huge_term(H5HF_hdr_t *hdr, hid_t dxpl_id)
         HDassert(hdr->huge_size == 0);
 
         /* Delete the v2 B-tree */
-        if(H5B2_delete(hdr->f, dxpl_id, &hdr->huge_bt2_class, hdr->huge_bt2_addr, NULL, NULL) < 0)
+        /* (any v2 B-tree class will work here) */
+        if(H5B2_delete(hdr->f, dxpl_id, H5HF_BT2_INDIR, hdr->huge_bt2_addr, NULL, NULL) < 0)
             HGOTO_ERROR(H5E_HEAP, H5E_CANTDELETE, FAIL, "can't delete v2 B-tree")
 
         /* Reset the information about 'huge' objects in the file */
@@ -568,8 +877,26 @@ H5HF_huge_delete(H5HF_hdr_t *hdr, hid_t dxpl_id)
     udata.dxpl_id = dxpl_id;
 
     /* Delete the v2 B-tree */
-    if(H5B2_delete(hdr->f, dxpl_id, &hdr->huge_bt2_class, hdr->huge_bt2_addr, H5HF_huge_bt2_remove, &udata) < 0)
-        HGOTO_ERROR(H5E_HEAP, H5E_CANTDELETE, FAIL, "can't delete v2 B-tree")
+    if(hdr->huge_ids_direct) {
+        if(hdr->filter_len > 0) {
+            if(H5B2_delete(hdr->f, dxpl_id, H5HF_BT2_FILT_DIR, hdr->huge_bt2_addr, H5HF_huge_bt2_filt_dir_remove, &udata) < 0)
+                HGOTO_ERROR(H5E_HEAP, H5E_CANTDELETE, FAIL, "can't delete v2 B-tree")
+        } /* end if */
+        else {
+            if(H5B2_delete(hdr->f, dxpl_id, H5HF_BT2_DIR, hdr->huge_bt2_addr, H5HF_huge_bt2_dir_remove, &udata) < 0)
+                HGOTO_ERROR(H5E_HEAP, H5E_CANTDELETE, FAIL, "can't delete v2 B-tree")
+        } /* end else */
+    } /* end if */
+    else {
+        if(hdr->filter_len > 0) {
+            if(H5B2_delete(hdr->f, dxpl_id, H5HF_BT2_FILT_INDIR, hdr->huge_bt2_addr, H5HF_huge_bt2_filt_indir_remove, &udata) < 0)
+                HGOTO_ERROR(H5E_HEAP, H5E_CANTDELETE, FAIL, "can't delete v2 B-tree")
+        } /* end if */
+        else {
+            if(H5B2_delete(hdr->f, dxpl_id, H5HF_BT2_INDIR, hdr->huge_bt2_addr, H5HF_huge_bt2_indir_remove, &udata) < 0)
+                HGOTO_ERROR(H5E_HEAP, H5E_CANTDELETE, FAIL, "can't delete v2 B-tree")
+        } /* end else */
+    } /* end else */
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
diff --git a/src/H5HFiblock.c b/src/H5HFiblock.c
index 7bb7884..70e3aac 100644
--- a/src/H5HFiblock.c
+++ b/src/H5HFiblock.c
@@ -70,6 +70,9 @@ H5FL_DEFINE(H5HF_indirect_t);
 /* Declare a free list to manage the H5HF_indirect_ent_t sequence information */
 H5FL_SEQ_DEFINE(H5HF_indirect_ent_t);
 
+/* Declare a free list to manage the H5HF_indirect_filt_ent_t sequence information */
+H5FL_SEQ_DEFINE(H5HF_indirect_filt_ent_t);
+
 
 /*****************************/
 /* Library Private Variables */
@@ -154,24 +157,12 @@ HDfprintf(stderr, "%s: iblock->block_off = %Hu\n", FUNC, iblock->block_off);
 
     /* Mark block as evictable again when no child blocks depend on it */
     if(iblock->rc == 0) {
-        H5HF_indirect_t *tmp_iblock = NULL;     /* Temporary pointer to indirect block */
-
 #ifdef QAK
 HDfprintf(stderr, "%s: indirect block ref. count at zero, iblock->addr = %a\n", FUNC, iblock->addr);
 #endif /* QAK */
-        /* Lock indirect block */
-        if(iblock->nchildren == 0) {
-            if(NULL == (tmp_iblock = H5HF_man_iblock_protect(iblock->hdr, H5AC_dxpl_id, iblock->addr, iblock->nrows, NULL, 0, H5AC_WRITE)))
-                HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "unable to protect fractal heap indirect block")
-            HDassert(tmp_iblock == iblock);
-        } /* end if */
-
         if(H5AC_unpin_entry(iblock->hdr->f, iblock) < 0)
             HGOTO_ERROR(H5E_HEAP, H5E_CANTUNPIN, FAIL, "unable to unpin fractal heap indirect block")
 
-/* XXX: If the indirect block has no children, delete indirect block's entry
- *      from cache.
- */
         if(iblock->nchildren == 0) {
 #ifdef QAK
 HDfprintf(stderr, "%s: Removing indirect block from cache, iblock->addr = %a\n", FUNC, iblock->addr);
@@ -200,10 +191,9 @@ HDfprintf(stderr, "%s: Removing indirect block from cache, iblock->addr = %a\n",
             if(H5MF_xfree(iblock->hdr->f, H5FD_MEM_FHEAP_IBLOCK, H5AC_dxpl_id, iblock->addr, (hsize_t)iblock->size) < 0)
                 HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to free fractal heap indirect block disk space")
 
-            /* Unlock indirect block with delete flag */
-            if(H5AC_unprotect(iblock->hdr->f, H5AC_dxpl_id, H5AC_FHEAP_IBLOCK, iblock->addr, tmp_iblock, H5AC__DIRTIED_FLAG|H5AC__DELETED_FLAG) < 0)
-                HGOTO_ERROR(H5E_HEAP, H5E_CANTUNPROTECT, FAIL, "unable to release fractal heap indirect block")
-            tmp_iblock = NULL;
+            /* Evict the indirect block from the metadata cache */
+            if(H5AC_expunge_entry(iblock->hdr->f, H5AC_dxpl_id, H5AC_FHEAP_IBLOCK, iblock->addr) < 0)
+                HGOTO_ERROR(H5E_HEAP, H5E_CANTREMOVE, FAIL, "unable to remove indirect block from cache")
         } /* end if */
     } /* end if */
 
@@ -488,15 +478,14 @@ HDfprintf(stderr, "%s: Check 1.0 - iblock->addr = %a, new_addr = %a\n", FUNC, ib
         iblock->addr = new_addr;
     } /* end if */
 
-    /* Re-allocate direct block entry table */
+    /* Re-allocate child block entry array */
     if(NULL == (iblock->ents = H5FL_SEQ_REALLOC(H5HF_indirect_ent_t, iblock->ents, (size_t)(iblock->nrows * hdr->man_dtable.cparam.width))))
-        HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed for direct entries")
+        HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, FAIL, "memory allocation failed for direct entries")
 
     /* Check for skipping over rows and add free section for skipped rows */
     if(skip_direct_rows) {
         /* Add skipped blocks to heap's free space */
-        if(H5HF_hdr_skip_blocks(hdr, dxpl_id, iblock, next_entry,
-                (new_next_entry - next_entry)) < 0)
+        if(H5HF_hdr_skip_blocks(hdr, dxpl_id, iblock, next_entry, (new_next_entry - next_entry)) < 0)
             HGOTO_ERROR(H5E_HEAP, H5E_CANTDEC, FAIL, "can't add skipped blocks to heap's free space")
     } /* end if */
 
@@ -509,6 +498,26 @@ HDfprintf(stderr, "%s: Check 1.0 - iblock->addr = %a, new_addr = %a\n", FUNC, ib
         acc_dblock_free += hdr->man_dtable.row_tot_dblock_free[row];
     } /* end for */
 
+    /* Check for needing to re-allocate filtered entry array */
+    if(hdr->filter_len > 0 && old_nrows < hdr->man_dtable.max_direct_rows) {
+        unsigned dir_rows;      /* Number of direct rows in this indirect block */
+
+        /* Compute the number of direct rows for this indirect block */
+        dir_rows = MIN(iblock->nrows, hdr->man_dtable.max_direct_rows);
+HDfprintf(stderr, "%s: dir_rows = %u\n", FUNC, dir_rows);
+        HDassert(dir_rows > old_nrows);
+
+        /* Re-allocate filtered direct block entry array */
+        if(NULL == (iblock->filt_ents = H5FL_SEQ_REALLOC(H5HF_indirect_filt_ent_t, iblock->filt_ents, (size_t)(dir_rows * hdr->man_dtable.cparam.width))))
+            HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, FAIL, "memory allocation failed for filtered direct entries")
+
+        /* Initialize new entries allocated */
+        for(u = (old_nrows * hdr->man_dtable.cparam.width); u < (dir_rows * hdr->man_dtable.cparam.width); u++) {
+            iblock->filt_ents[u].size = 0;
+            iblock->filt_ents[u].filter_mask = 0;
+        } /* end for */
+    } /* end if */
+
     /* Mark indirect block as dirty */
     if(H5HF_iblock_dirty(iblock) < 0)
         HGOTO_ERROR(H5E_HEAP, H5E_CANTDIRTY, FAIL, "can't mark indirect block as dirty")
@@ -612,10 +621,17 @@ HDfprintf(stderr, "%s: new_addr = %a\n", FUNC, new_addr);
         iblock->addr = new_addr;
     } /* end if */
 
-    /* Re-allocate direct block entry table */
+    /* Re-allocate child block entry array */
     if(NULL == (iblock->ents = H5FL_SEQ_REALLOC(H5HF_indirect_ent_t, iblock->ents, (iblock->nrows * hdr->man_dtable.cparam.width))))
         HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed for direct entries")
 
+    /* Check for needing to re-allocate filtered entry array */
+    if(hdr->filter_len > 0 && new_nrows < hdr->man_dtable.max_direct_rows) {
+        /* Re-allocate filtered direct block entry array */
+        if(NULL == (iblock->filt_ents = H5FL_SEQ_REALLOC(H5HF_indirect_filt_ent_t, iblock->filt_ents, (size_t)(iblock->nrows * hdr->man_dtable.cparam.width))))
+            HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, FAIL, "memory allocation failed for filtered direct entries")
+    } /* end if */
+
     /* Mark indirect block as dirty */
     if(H5HF_iblock_dirty(iblock) < 0)
         HGOTO_ERROR(H5E_HEAP, H5E_CANTDIRTY, FAIL, "can't mark indirect block as dirty")
@@ -842,7 +858,7 @@ HDfprintf(stderr, "%s: nrows = %u, max_rows = %u\n", FUNC, nrows, max_rows);
     /* Compute size of buffer needed for indirect block */
     iblock->size = H5HF_MAN_INDIRECT_SIZE(hdr, iblock);
 
-    /* Allocate indirect block entry tables */
+    /* Allocate child block entry array */
     if(NULL == (iblock->ents = H5FL_SEQ_MALLOC(H5HF_indirect_ent_t, (size_t)(iblock->nrows * hdr->man_dtable.cparam.width))))
 	HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed for block entries")
 
@@ -850,6 +866,23 @@ HDfprintf(stderr, "%s: nrows = %u, max_rows = %u\n", FUNC, nrows, max_rows);
     for(u = 0; u < (iblock->nrows * hdr->man_dtable.cparam.width); u++)
         iblock->ents[u].addr = HADDR_UNDEF;
 
+    /* Check for I/O filters to apply to this heap */
+    if(hdr->filter_len > 0) {
+        unsigned dir_rows;      /* Number of direct rows in this indirect block */
+
+        /* Compute the number of direct rows for this indirect block */
+        dir_rows = MIN(iblock->nrows, hdr->man_dtable.max_direct_rows);
+#ifdef QAK
+HDfprintf(stderr, "%s: dir_rows = %u\n", FUNC, dir_rows);
+#endif /* QAK */
+
+        /* Allocate & initialize indirect block filtered entry array */
+        if(NULL == (iblock->filt_ents = H5FL_SEQ_CALLOC(H5HF_indirect_filt_ent_t, (size_t)(dir_rows * hdr->man_dtable.cparam.width))))
+            HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed for block entries")
+    } /* end if */
+    else
+        iblock->filt_ents = NULL;
+
     /* Allocate space for the indirect block on disk */
     if(HADDR_UNDEF == (*addr_p = H5MF_alloc(hdr->f, H5FD_MEM_FHEAP_IBLOCK, dxpl_id, (hsize_t)iblock->size)))
 	HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "file allocation failed for fractal heap indirect block")
@@ -979,6 +1012,21 @@ HDfprintf(stderr, "%s: iblock->block_off = %Hu, iblock->nchildren = %u\n", FUNC,
     /* Point at the direct block */
     iblock->ents[entry].addr = child_addr;
 
+    /* Check for I/O filters on this heap */
+    if(iblock->hdr->filter_len > 0) {
+        unsigned row;           /* Row for entry */
+
+        /* Sanity check */
+        HDassert(iblock->filt_ents);
+
+        /* Compute row for entry */
+        row = entry / iblock->hdr->man_dtable.cparam.width;
+
+        /* If this is a direct block, set its initial size */
+        if(row < iblock->hdr->man_dtable.max_direct_rows)
+            iblock->filt_ents[entry].size = iblock->hdr->man_dtable.row_block_size[row];
+    } /* end if */
+
     /* Check for max. entry used */
     if(entry > iblock->max_child)
         iblock->max_child = entry;
@@ -1028,9 +1076,26 @@ HDfprintf(stderr, "%s: iblock->block_off = %Hu, iblock->nchildren = %u\n", FUNC,
     /* Reset address of entry */
     iblock->ents[entry].addr = HADDR_UNDEF;
 
+    /* Check for I/O filters on this heap */
+    if(iblock->hdr->filter_len > 0) {
+        unsigned row;           /* Row for entry */
+
+        /* Sanity check */
+        HDassert(iblock->filt_ents);
+
+        /* Compute row for entry */
+        row = entry / iblock->hdr->man_dtable.cparam.width;
+
+        /* If this is a direct block, set its initial size */
+        if(row < iblock->hdr->man_dtable.max_direct_rows) {
+            iblock->filt_ents[entry].size = 0;
+            iblock->filt_ents[entry].filter_mask = 0;
+        } /* end if */
+    } /* end if */
+
     /* Decrement the # of child blocks */
     /* (If the number of children drop to 0, the indirect block will be
-     *  removed from the heap when it's ref. count drops to zero and the
+     *  removed from the heap when its ref. count drops to zero and the
      *  metadata cache calls the indirect block destructor)
      */
     iblock->nchildren--;
@@ -1113,7 +1178,7 @@ H5HF_man_iblock_entry_addr(H5HF_indirect_t *iblock, unsigned entry, haddr_t *chi
     HDassert(iblock);
     HDassert(child_addr);
 
-    /* Reset address of entry */
+    /* Retrieve address of entry */
     *child_addr = iblock->ents[entry].addr;
 
     FUNC_LEAVE_NOAPI(SUCCEED)
diff --git a/src/H5HFman.c b/src/H5HFman.c
index 30eb31c..38e8d43 100644
--- a/src/H5HFman.c
+++ b/src/H5HFman.c
@@ -18,7 +18,7 @@
  *			Feb 24 2006
  *			Quincey Koziol <koziol@ncsa.uiuc.edu>
  *
- * Purpose:		"Internal" routines for fractal heaps.
+ * Purpose:		"Managed" object routines for fractal heaps.
  *
  *-------------------------------------------------------------------------
  */
@@ -394,6 +394,9 @@ H5HF_man_read(H5HF_hdr_t *hdr, hid_t dxpl_id, const uint8_t *id, void *obj)
     HDassert(id);
     HDassert(obj);
 
+    /* Skip over the flag byte */
+    id++;
+
     /* Decode the object offset within the heap & it's length */
     UINT64DECODE_VAR(id, obj_off, hdr->heap_off_size);
     UINT64DECODE_VAR(id, obj_len, hdr->heap_len_size);
@@ -494,6 +497,9 @@ H5HF_man_remove(H5HF_hdr_t *hdr, hid_t dxpl_id, const uint8_t *id)
     HDassert(hdr);
     HDassert(id);
 
+    /* Skip over the flag byte */
+    id++;
+
     /* Decode the object offset within the heap & it's length */
 #ifdef QAK
 HDfprintf(stderr, "%s: fh->hdr->heap_off_size = %u, fh->hdr->heap_len_size = %u\n", FUNC, (unsigned)fh->hdr->heap_off_size, (unsigned)fh->hdr->heap_len_size);
diff --git a/src/H5HFpkg.h b/src/H5HFpkg.h
index 21e5468..947f3ad 100644
--- a/src/H5HFpkg.h
+++ b/src/H5HFpkg.h
@@ -72,6 +72,9 @@
 #define H5HF_HDR_FLAGS_HUGE_ID_WRAPPED 0x01
 
 /* Size of the fractal heap header on disk */
+/* (this is the fixed-len portion, the variable-len I/O filter information
+ *      follows this information, if there are I/O filters for the heap)
+ */
 #define H5HF_HEADER_SIZE(h)     (                                             \
     /* General metadata fields */                                             \
     H5HF_METADATA_PREFIX_SIZE                                                 \
@@ -80,6 +83,7 @@
                                                                               \
     /* General heap information */                                            \
     + 2 /* Heap ID len */                                                     \
+    + 2 /* I/O filters' encoded len */                                        \
     + 1 /* Status flags */                                                    \
                                                                               \
     /* "Huge" object fields */                                                \
@@ -98,6 +102,8 @@
     + (h)->sizeof_size /* Number of man. objects in heap */                   \
     + (h)->sizeof_size /* Size of huge space in heap */                       \
     + (h)->sizeof_size /* Number of huge objects in heap */                   \
+    + (h)->sizeof_size /* Size of tiny space in heap */                       \
+    + (h)->sizeof_size /* Number of tiny objects in heap */                   \
                                                                               \
     /* "Managed" object doubling table info */                                \
     + H5HF_DTABLE_INFO_SIZE(h) /* Size of managed obj. doubling-table info */ \
@@ -113,7 +119,14 @@
     + (h)->heap_off_size        /* Offset of the block in the heap */         \
     )
 
-/* Size of managed indirect block (absolute & mapped) */
+/* Size of managed indirect block entry for a child direct block */
+#define H5HF_MAN_INDIRECT_CHILD_DIR_ENTRY_SIZE(h) (                           \
+    ((h)->filter_len > 0 ?                                                    \
+        ((h)->sizeof_addr + (h)->sizeof_size + 4) : /* Size of entries for filtered direct blocks */ \
+        (h)->sizeof_addr)             /* Size of entries for un-filtered direct blocks */ \
+    )
+
+/* Size of managed indirect block */
 #define H5HF_MAN_INDIRECT_SIZE(h, i) (                                        \
     /* General metadata fields */                                             \
     H5HF_METADATA_PREFIX_SIZE                                                 \
@@ -121,7 +134,7 @@
     /* Fractal heap managed, absolutely mapped indirect block specific fields */ \
     + (h)->sizeof_addr          /* File address of heap owning the block */   \
     + (h)->heap_off_size        /* Offset of the block in the heap */         \
-    + (MIN((i)->nrows, (h)->man_dtable.max_direct_rows) * (h)->man_dtable.cparam.width * (h)->sizeof_addr) /* Size of entries for direct blocks */ \
+    + (MIN((i)->nrows, (h)->man_dtable.max_direct_rows) * (h)->man_dtable.cparam.width * H5HF_MAN_INDIRECT_CHILD_DIR_ENTRY_SIZE(h)) /* Size of entries for direct blocks */ \
     + ((((i)->nrows > (h)->man_dtable.max_direct_rows) ? ((i)->nrows - (h)->man_dtable.max_direct_rows) : 0)  * (h)->man_dtable.cparam.width * (h)->sizeof_addr) /* Size of entries for indirect blocks */ \
     )
 
@@ -289,12 +302,12 @@ typedef struct H5HF_hdr_t {
 
     /* General header information (stored in header) */
     unsigned    id_len;         /* Size of heap IDs (in bytes) */
+    unsigned    filter_len;     /* Size of I/O filter information (in bytes) */
 
     /* Flags for heap settings (stored in status byte in header) */
     hbool_t     debug_objs;     /* Is the heap storing objects in 'debug' format */
-    hbool_t     have_io_filter; /* Does the heap have I/O filters for the direct blocks? */
     hbool_t     write_once;     /* Is heap being written in "write once" mode? */
-    hbool_t     huge_ids_wrapped;   /* Have "huge" object IDs wrapped around? */
+    hbool_t     huge_ids_wrapped; /* Have "huge" object IDs wrapped around? */
 
     /* Doubling table information (partially stored in header) */
     /* (Partially set by user, partially derived/updated internally) */
@@ -309,38 +322,54 @@ typedef struct H5HF_hdr_t {
     hsize_t  huge_next_id;      /* Next ID to use for indirectly tracked 'huge' object */
     haddr_t  huge_bt2_addr;     /* Address of v2 B-tree for tracking "huge" object info */
 
+    /* I/O filter support (stored in header, if any are used) */
+    H5O_pline_t pline;          /* I/O filter pipeline for heap objects */
+    size_t pline_root_direct_size;    /* Size of filtered root direct block */
+    unsigned pline_root_direct_filter_mask; /* I/O filter mask for filtered root direct block */
+
     /* Statistics for heap (stored in header) */
-    hsize_t     man_size;       /* Total amount of managed space in heap */
-    hsize_t     man_alloc_size; /* Total amount of allocated managed space in heap */
-    hsize_t     man_iter_off;   /* Offset of iterator in managed heap space */
-    hsize_t     man_nobjs;      /* Number of "managed" objects in heap */
-    hsize_t     huge_size;      /* Total size of "huge" objects in heap */
-    hsize_t     huge_nobjs;     /* Number of "huge" objects in heap */
+    hsize_t     man_size;       /* Total amount of 'managed' space in heap */
+    hsize_t     man_alloc_size; /* Total amount of allocated 'managed' space in heap */
+    hsize_t     man_iter_off;   /* Offset of iterator in 'managed' heap space */
+    hsize_t     man_nobjs;      /* Number of 'managed' objects in heap */
+    hsize_t     huge_size;      /* Total size of 'huge' objects in heap */
+    hsize_t     huge_nobjs;     /* Number of 'huge' objects in heap */
+    hsize_t     tiny_size;      /* Total size of 'tiny' objects in heap */
+    hsize_t     tiny_nobjs;     /* Number of 'tiny' objects in heap */
 
     /* Cached/computed values (not stored in header) */
     size_t      rc;             /* Reference count of objects using heap header */
     hbool_t     dirty;          /* Shared info is modified */
     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 */
     H5F_t      *f;              /* Pointer to file for heap */
     size_t      sizeof_size;    /* Size of file sizes */
     size_t      sizeof_addr;    /* Size of file addresses */
     H5FS_t      *fspace;        /* Free space list for objects in heap */
     H5HF_block_iter_t next_block;   /* Block iterator for searching for next block with space */
-    H5B2_class_t huge_bt2_class; /* v2 B-tree class information for "huge" object tracking */
     hsize_t     huge_max_id;    /* Max. 'huge' heap ID before rolling 'huge' heap IDs over */
     hbool_t     huge_ids_direct; /* Flag to indicate that 'huge' object's offset & length are stored directly in heap ID */
-    unsigned char huge_id_size;   /* Size of 'huge' heap IDs (in bytes) */
+    size_t      tiny_max_len;   /* Max. size of tiny objects for this heap */
+    hbool_t     tiny_len_extended; /* Flag to indicate that 'tiny' object's length is stored in extended form (i.e. w/extra byte) */
+    unsigned char huge_id_size; /* Size of 'huge' heap IDs (in bytes) */
     unsigned char heap_off_size; /* Size of heap offsets (in bytes) */
     unsigned char heap_len_size; /* Size of heap ID lengths (in bytes) */
 } H5HF_hdr_t;
 
-/* Indirect block entry */
+/* Common indirect block doubling table entry */
+/* (common between entries pointing to direct & indirect child blocks) */
 typedef struct H5HF_indirect_ent_t {
     haddr_t     addr;           /* Direct block's address                     */
-/* XXX: Will need space for block size, for blocks with I/O filters */
 } H5HF_indirect_ent_t;
 
+/* Extern indirect block doubling table entry for compressed direct blocks */
+/* (only exists for indirect blocks in heaps that have I/O filters) */
+typedef struct H5HF_indirect_filt_ent_t {
+    size_t     size;            /* Size of child direct block, after passing though I/O filters */
+    unsigned	filter_mask;	/* Excluded filters for child direct block */
+} H5HF_indirect_filt_ent_t;
+
 /* Fractal heap indirect block */
 struct H5HF_indirect_t {
     /* Information for H5AC cache functions, _must_ be first field in structure */
@@ -361,6 +390,7 @@ struct H5HF_indirect_t {
     /* Stored values */
     hsize_t     block_off;      /* Offset of the block within the heap's address space */
     H5HF_indirect_ent_t *ents;  /* Pointer to block entry table               */
+    H5HF_indirect_filt_ent_t *filt_ents;    /* Pointer to filtered information for direct blocks */
 };
 
 /* A fractal heap direct block */
@@ -393,6 +423,36 @@ typedef struct H5HF_parent_t {
     unsigned entry;             /* Location of block in parent's entry table */
 } H5HF_parent_t;
 
+/* Typedef for indirectly accessed 'huge' object's records in the v2 B-tree */
+typedef struct H5HF_huge_bt2_indir_rec_t {
+    haddr_t addr;       /* Address of the object in the file */
+    hsize_t len;        /* Length of the object in the file */
+    hsize_t id;         /* ID used for object (not used for 'huge' objects directly accessed) */
+} H5HF_huge_bt2_indir_rec_t;
+
+/* Typedef for indirectly accessed, filtered 'huge' object's records in the v2 B-tree */
+typedef struct H5HF_huge_bt2_filt_indir_rec_t {
+    haddr_t addr;       /* Address of the filtered object in the file */
+    hsize_t len;        /* Length of the filtered object in the file */
+    unsigned filter_mask;   /* I/O pipeline filter mask for filtered object in the file */
+    hsize_t obj_size;   /* Size of the de-filtered object in memory */
+    hsize_t id;         /* ID used for object (not used for 'huge' objects directly accessed) */
+} H5HF_huge_bt2_filt_indir_rec_t;
+
+/* Typedef for directly accessed 'huge' object's records in the v2 B-tree */
+typedef struct H5HF_huge_bt2_dir_rec_t {
+    haddr_t addr;       /* Address of the object in the file */
+    hsize_t len;        /* Length of the object in the file */
+} H5HF_huge_bt2_dir_rec_t;
+
+/* Typedef for directly accessed, filtered 'huge' object's records in the v2 B-tree */
+typedef struct H5HF_huge_bt2_filt_dir_rec_t {
+    haddr_t addr;       /* Address of the filtered object in the file */
+    hsize_t len;        /* Length of the filtered object in the file */
+    unsigned filter_mask;   /* I/O pipeline filter mask for filtered object in the file */
+    hsize_t obj_size;   /* Size of the de-filtered object in memory */
+} H5HF_huge_bt2_filt_dir_rec_t;
+
 /* User data for free space section 'add' callback */
 typedef struct {
     H5HF_hdr_t *hdr;            /* Fractal heap header */
@@ -406,13 +466,6 @@ typedef struct {
     hsize_t obj_len;            /* Length of object removed (out) */
 } H5HF_huge_remove_ud1_t;
 
-/* Typedef for 'huge' object's records in the v2 B-tree */
-typedef struct H5HF_huge_bt2_rec_t {
-    haddr_t addr;       /* Address of the object in the file */
-    hsize_t len;        /* Length of the object in the file */
-    hsize_t id;         /* ID used for object (not used for 'huge' objects directly accessed) */
-} H5HF_huge_bt2_rec_t;
-
 /*****************************/
 /* Package Private Variables */
 /*****************************/
@@ -426,6 +479,18 @@ H5_DLLVAR const H5AC_class_t H5AC_FHEAP_DBLOCK[1];
 /* H5HF indirect block inherits cache-like properties from H5AC */
 H5_DLLVAR const H5AC_class_t H5AC_FHEAP_IBLOCK[1];
 
+/* The v2 B-tree class for tracking indirectly accessed 'huge' objects */
+H5_DLLVAR const H5B2_class_t H5HF_BT2_INDIR[1];
+
+/* The v2 B-tree class for tracking indirectly accessed filtered 'huge' objects */
+H5_DLLVAR const H5B2_class_t H5HF_BT2_FILT_INDIR[1];
+
+/* The v2 B-tree class for tracking directly accessed 'huge' objects */
+H5_DLLVAR const H5B2_class_t H5HF_BT2_DIR[1];
+
+/* The v2 B-tree class for tracking directly accessed filtered 'huge' objects */
+H5_DLLVAR const H5B2_class_t H5HF_BT2_FILT_DIR[1];
+
 /* H5HF single section inherits serializable properties from H5FS_section_class_t */
 H5_DLLVAR H5FS_section_class_t H5HF_FSPACE_SECT_CLS_SINGLE[1];
 
@@ -453,6 +518,9 @@ H5FL_EXTERN(H5HF_indirect_t);
 /* Declare a free list to manage the H5HF_indirect_ent_t sequence information */
 H5FL_SEQ_EXTERN(H5HF_indirect_ent_t);
 
+/* Declare a free list to manage the H5HF_indirect_filt_ent_t sequence information */
+H5FL_SEQ_EXTERN(H5HF_indirect_filt_ent_t);
+
 
 /******************************/
 /* Package Private Prototypes */
@@ -543,10 +611,10 @@ H5_DLL herr_t H5HF_man_read(H5HF_hdr_t *fh, hid_t dxpl_id, const uint8_t *id,
     void *obj);
 H5_DLL herr_t H5HF_man_remove(H5HF_hdr_t *hdr, hid_t dxpl_id, const uint8_t *id);
 
-/* "Huge" object routines */
+/* 'Huge' object routines */
 H5_DLL herr_t H5HF_huge_init(H5HF_hdr_t *hdr);
 H5_DLL herr_t H5HF_huge_insert(H5HF_hdr_t *hdr, hid_t dxpl_id, size_t obj_size,
-    const void *obj, void *id);
+    void *obj, void *id);
 H5_DLL herr_t H5HF_huge_get_obj_len(H5HF_hdr_t *hdr, hid_t dxpl_id,
     const uint8_t *id, size_t *obj_len_p);
 H5_DLL herr_t H5HF_huge_read(H5HF_hdr_t *fh, hid_t dxpl_id, const uint8_t *id,
@@ -555,6 +623,15 @@ H5_DLL herr_t H5HF_huge_remove(H5HF_hdr_t *fh, hid_t dxpl_id, const uint8_t *id)
 H5_DLL herr_t H5HF_huge_term(H5HF_hdr_t *hdr, hid_t dxpl_id);
 H5_DLL herr_t H5HF_huge_delete(H5HF_hdr_t *hdr, hid_t dxpl_id);
 
+/* 'Tiny' object routines */
+H5_DLL herr_t H5HF_tiny_init(H5HF_hdr_t *hdr);
+H5_DLL herr_t H5HF_tiny_insert(H5HF_hdr_t *hdr, size_t obj_size, const void *obj,
+    void *id);
+H5_DLL herr_t H5HF_tiny_get_obj_len(H5HF_hdr_t *hdr, const uint8_t *id,
+    size_t *obj_len_p);
+H5_DLL herr_t H5HF_tiny_read(H5HF_hdr_t *fh, const uint8_t *id, void *obj);
+H5_DLL herr_t H5HF_tiny_remove(H5HF_hdr_t *fh, const uint8_t *id);
+
 /* Metadata cache callbacks */
 H5_DLL herr_t H5HF_cache_hdr_dest(H5F_t *f, H5HF_hdr_t *hdr);
 H5_DLL herr_t H5HF_cache_dblock_dest(H5F_t *f, H5HF_direct_t *dblock);
@@ -619,6 +696,7 @@ H5_DLL herr_t H5HF_sect_indirect_add(H5HF_hdr_t *hdr, hid_t dxpl_id,
 /* Testing routines */
 #ifdef H5HF_TESTING
 H5_DLL herr_t H5HF_get_cparam_test(const H5HF_t *fh, H5HF_create_t *cparam);
+H5_DLL int H5HF_cmp_cparam_test(const H5HF_create_t *cparam1, const H5HF_create_t *cparam2);
 H5_DLL unsigned H5HF_get_max_root_rows(const H5HF_t *fh);
 H5_DLL unsigned H5HF_get_dtable_width_test(const H5HF_t *fh);
 H5_DLL unsigned H5HF_get_dtable_max_drows_test(const H5HF_t *fh);
@@ -626,6 +704,12 @@ H5_DLL unsigned H5HF_get_iblock_max_drows_test(const H5HF_t *fh, unsigned pos);
 H5_DLL hsize_t H5HF_get_dblock_size_test(const H5HF_t *fh, unsigned row);
 H5_DLL hsize_t H5HF_get_dblock_free_test(const H5HF_t *fh, unsigned row);
 H5_DLL herr_t H5HF_get_id_off_test(const H5HF_t *fh, const void *id, hsize_t *obj_off);
+H5_DLL herr_t H5HF_get_id_type_test(const H5HF_t *fh, const void *id,
+    unsigned char *obj_type);
+H5_DLL herr_t H5HF_get_tiny_info_test(const H5HF_t *fh, size_t *max_len,
+    hbool_t *len_extended);
+H5_DLL herr_t H5HF_get_huge_info_test(const H5HF_t *fh, hsize_t *next_id,
+    hbool_t *ids_direct);
 #endif /* H5HF_TESTING */
 
 #endif /* _H5HFpkg_H */
diff --git a/src/H5HFprivate.h b/src/H5HFprivate.h
index 1c9a3ba..20415c1 100644
--- a/src/H5HFprivate.h
+++ b/src/H5HFprivate.h
@@ -31,11 +31,17 @@
 
 /* Private headers needed by this file */
 #include "H5Fprivate.h"		/* File access				*/
+#include "H5Oprivate.h"		/* Object headers		  	*/
 
 /**************************/
 /* Library Private Macros */
 /**************************/
 
+/* Limit heap ID length to 4096 + 1, due to # of bits required to store
+ *      length of 'tiny' objects (12 bits)
+ */
+#define H5HF_MAX_ID_LEN         (4096 + 1)
+
 
 /****************************/
 /* Library Private Typedefs */
@@ -60,22 +66,27 @@ typedef struct H5HF_create_t {
                                 /* (i.e.  min. size of object to store standalone) */
     uint16_t id_len;            /* Length of IDs to use for heap objects */
                                 /* (0 - make ID just large enough to hold length & offset of object in the heap) */
-                                /* (1 - make ID just large enough to allow 'huge' objects to hold the file address & length of the 'huge' object) */
+                                /* (1 - make ID just large enough to allow 'huge' objects to be accessed directly) */
                                 /* (n - make ID 'n' bytes in size) */
+    H5O_pline_t pline;          /* I/O filter pipeline to apply to direct blocks & 'huge' objects */
 } H5HF_create_t;
 
 /* Fractal heap metadata statistics info */
 typedef struct H5HF_stat_t {
-    /* "Managed" object info */
-    hsize_t man_size;           /* Size of managed space in heap              */
-    hsize_t man_alloc_size;     /* Size of managed space allocated in heap    */
-    hsize_t man_iter_off;       /* Offset of "new block" iterator in managed heap space */
-    hsize_t man_free_space;     /* Free space within managed heap blocks      */
-    hsize_t man_nobjs;          /* Number of "managed" objects in heap        */
-
-    /* "Huge" object info */
-    hsize_t huge_size;          /* Size of "huge" objects in heap             */
-    hsize_t huge_nobjs;         /* Number of "huge" objects in heap           */
+    /* 'Managed' object info */
+    hsize_t man_size;           /* Size of 'managed' space in heap            */
+    hsize_t man_alloc_size;     /* Size of 'managed' space allocated in heap  */
+    hsize_t man_iter_off;       /* Offset of "new block" iterator in 'managed' heap space */
+    hsize_t man_free_space;     /* Free space within 'managed' heap blocks    */
+    hsize_t man_nobjs;          /* Number of 'managed' objects in heap        */
+
+    /* 'Huge' object info */
+    hsize_t huge_size;          /* Size of 'huge' objects in heap             */
+    hsize_t huge_nobjs;         /* Number of 'huge' objects in heap           */
+
+    /* 'Tiny' object info */
+    hsize_t tiny_size;          /* Size of 'tiny' objects in heap             */
+    hsize_t tiny_nobjs;         /* Number of 'tiny' objects in heap           */
 } H5HF_stat_t;
 
 /* Fractal heap info (forward decl - defined in H5HFpkg.h) */
diff --git a/src/H5HFstat.c b/src/H5HFstat.c
index 0924dae..1c6e887 100644
--- a/src/H5HFstat.c
+++ b/src/H5HFstat.c
@@ -99,6 +99,8 @@ H5HF_stat_info(const H5HF_t *fh, H5HF_stat_t *stats)
     stats->man_free_space = fh->hdr->total_man_free;
     stats->huge_size = fh->hdr->huge_size;
     stats->huge_nobjs = fh->hdr->huge_nobjs;
+    stats->tiny_size = fh->hdr->tiny_size;
+    stats->tiny_nobjs = fh->hdr->tiny_nobjs;
 /* XXX: Add more metadata statistics for the heap */
 
     FUNC_LEAVE_NOAPI(SUCCEED)
diff --git a/src/H5HFtest.c b/src/H5HFtest.c
index d1daa2b..bbe93ca 100644
--- a/src/H5HFtest.c
+++ b/src/H5HFtest.c
@@ -93,14 +93,122 @@ H5HF_get_cparam_test(const H5HF_t *fh, H5HF_create_t *cparam)
     HDassert(cparam);
 
     /* Get fractal heap creation parameters */
+    if(fh->hdr->id_len == (unsigned)(1 + fh->hdr->heap_off_size + fh->hdr->heap_len_size))
+        cparam->id_len = 0;
+    else if(fh->hdr->id_len == (1 + fh->hdr->sizeof_size + fh->hdr->sizeof_addr))
+        cparam->id_len = 1;
+    else
+        cparam->id_len = fh->hdr->id_len;
     cparam->max_man_size = fh->hdr->max_man_size;
     HDmemcpy(&(cparam->managed), &(fh->hdr->man_dtable.cparam), sizeof(H5HF_dtable_cparam_t));
+    H5O_copy(H5O_PLINE_ID, &(fh->hdr->pline), &(cparam->pline));
 
     FUNC_LEAVE_NOAPI(SUCCEED)
 } /* H5HF_get_cparam_test() */
 
 
 /*-------------------------------------------------------------------------
+ * Function:	H5HF_cmp_cparam_test
+ *
+ * Purpose:	Compare the parameters used to create the fractal heap
+ *
+ * Return:	Success:	non-negative
+ *		Failure:	negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Monday, August 14, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+int
+H5HF_cmp_cparam_test(const H5HF_create_t *cparam1, const H5HF_create_t *cparam2)
+{
+    int ret_value;         /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_cmp_cparam_test)
+
+    /* Check arguments. */
+    HDassert(cparam1);
+    HDassert(cparam2);
+
+    /* Compare doubling table parameters */
+    if((ret_value = HDmemcmp(&(cparam1->managed), &(cparam2->managed), sizeof(H5HF_dtable_cparam_t))))
+        HGOTO_DONE(ret_value)
+
+    /* Compare other general parameters for heap */
+    if(cparam1->max_man_size < cparam2->max_man_size)
+        HGOTO_DONE(-1)
+    else if(cparam1->max_man_size > cparam2->max_man_size)
+        HGOTO_DONE(1)
+    if(cparam1->id_len < cparam2->id_len)
+        HGOTO_DONE(-1)
+    else if(cparam1->id_len > cparam2->id_len)
+        HGOTO_DONE(1)
+
+    /* Compare "important" parameters for any I/O pipeline filters */
+    if(cparam1->pline.nused < cparam2->pline.nused)
+        HGOTO_DONE(-1)
+    else if(cparam1->pline.nused > cparam2->pline.nused)
+        HGOTO_DONE(1)
+    else {
+        size_t u, v;       /* Local index variables */
+
+        /* Compare each filter */
+        for(u = 0; u < cparam1->pline.nused; u++) {
+            /* Check filter ID */
+            if(cparam1->pline.filter[u].id < cparam2->pline.filter[u].id)
+                HGOTO_DONE(-1)
+            else if(cparam1->pline.filter[u].id > cparam2->pline.filter[u].id)
+                HGOTO_DONE(1)
+
+            /* Check filter flags */
+            if(cparam1->pline.filter[u].flags < cparam2->pline.filter[u].flags)
+                HGOTO_DONE(-1)
+            else if(cparam1->pline.filter[u].flags > cparam2->pline.filter[u].flags)
+                HGOTO_DONE(1)
+
+/* Don't worry about comparing the filter names right now... */
+/* (they are expanded during the encode/decode process, but aren't copied
+ *      during the H5Z_append operation, generating false positive failures)
+ */
+#ifdef QAK
+            /* Check filter name */
+HDfprintf(stderr, "%s: Check 1.0\n", "H5HF_cmp_cparam_test");
+HDfprintf(stderr, "%s: cparam1->pline.filter[%Zu].name = %s\n", "H5HF_cmp_cparam_test", u, (cparam1->pline.filter[u].name ? cparam1->pline.filter[u].name : "<nil>"));
+HDfprintf(stderr, "%s: cparam2->pline.filter[%Zu].name = %s\n", "H5HF_cmp_cparam_test", u, (cparam2->pline.filter[u].name ? cparam2->pline.filter[u].name : "<nil>"));
+            if(!cparam1->pline.filter[u].name && cparam2->pline.filter[u].name)
+                HGOTO_DONE(-1)
+            else if(cparam1->pline.filter[u].name && !cparam2->pline.filter[u].name)
+                HGOTO_DONE(1)
+            else if(cparam1->pline.filter[u].name && cparam2->pline.filter[u].name) {
+                if((ret_value = HDstrcmp(cparam1->pline.filter[u].name, cparam2->pline.filter[u].name)))
+                    HGOTO_DONE(ret_value)
+            } /* end if */
+#endif /* QAK */
+
+            /* Check # of filter parameters */
+            if(cparam1->pline.filter[u].cd_nelmts < cparam2->pline.filter[u].cd_nelmts)
+                HGOTO_DONE(-1)
+            else if(cparam1->pline.filter[u].cd_nelmts > cparam2->pline.filter[u].cd_nelmts)
+                HGOTO_DONE(1)
+
+            /* Check filter parameters */
+            for(v = 0; v < cparam1->pline.filter[u].cd_nelmts; v++) {
+                if(cparam1->pline.filter[u].cd_values[v] < cparam2->pline.filter[u].cd_values[v])
+                    HGOTO_DONE(-1)
+                else if(cparam1->pline.filter[u].cd_values[v] > cparam2->pline.filter[u].cd_values[v])
+                    HGOTO_DONE(1)
+            } /* end for */
+
+        } /* end for */
+    } /* end else */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5HF_get_cparam_test() */
+
+
+/*-------------------------------------------------------------------------
  * Function:	H5HF_get_max_root_rows
  *
  * Purpose:	Retrieve the max. # of rows in the root indirect block
@@ -296,7 +404,7 @@ H5HF_get_dblock_free_test(const H5HF_t *fh, unsigned row)
 /*-------------------------------------------------------------------------
  * Function:	H5HF_get_id_off_test
  *
- * Purpose:	Retrieve the offset for a heap ID
+ * Purpose:	Retrieve the offset for a [managed] heap ID
  *
  * Return:	Success:	non-negative
  *
@@ -322,8 +430,106 @@ H5HF_get_id_off_test(const H5HF_t *fh, const void *_id, hsize_t *obj_off)
 
     /* Get the offset for a 'normal' heap ID */
     id++;
-    UINT64DECODE_VAR(id, *obj_off, fh->hdr->heap_off_size);                           \
+    UINT64DECODE_VAR(id, *obj_off, fh->hdr->heap_off_size);
 
     FUNC_LEAVE_NOAPI(SUCCEED)
 } /* H5HF_get_id_off_test() */
 
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_get_id_type_test
+ *
+ * Purpose:	Retrieve the type of a heap ID
+ *
+ * Return:	Success:	non-negative
+ *		Failure:	negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Monday, August 14, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5HF_get_id_type_test(const H5HF_t *fh, const void *_id, unsigned char *obj_type)
+{
+    const uint8_t *id = (const uint8_t *)_id;   /* Object ID */
+
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_get_id_type_test)
+
+    /* Check arguments. */
+    HDassert(fh);
+    HDassert(fh->hdr);
+    HDassert(id);
+    HDassert(obj_type);
+
+    /* Get the type for a heap ID */
+    *obj_type = *id & H5HF_ID_TYPE_MASK;
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* H5HF_get_id_type_test() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_get_tiny_info_test
+ *
+ * Purpose:	Retrieve information about tiny object's ID length
+ *
+ * Return:	Success:	non-negative
+ *		Failure:	negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Monday, August 14, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5HF_get_tiny_info_test(const H5HF_t *fh, size_t *max_len,
+    hbool_t *len_extended)
+{
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_get_tiny_info_test)
+
+    /* Check arguments. */
+    HDassert(fh);
+    HDassert(fh->hdr);
+    HDassert(max_len);
+    HDassert(len_extended);
+
+    /* Retrieve information about tiny object's ID encoding in a heap */
+    *max_len = fh->hdr->tiny_max_len;
+    *len_extended = fh->hdr->tiny_len_extended;
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* H5HF_get_tiny_info_test() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_get_huge_info_test
+ *
+ * Purpose:	Retrieve information about huge object's ID length
+ *
+ * Return:	Success:	non-negative
+ *		Failure:	negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Monday, August 14, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5HF_get_huge_info_test(const H5HF_t *fh, hsize_t *next_id, hbool_t *ids_direct)
+{
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_get_huge_info_test)
+
+    /* Check arguments. */
+    HDassert(fh);
+    HDassert(fh->hdr);
+    HDassert(ids_direct);
+
+    /* Retrieve information about tiny object's ID encoding in a heap */
+    if(next_id)
+        *next_id = fh->hdr->huge_next_id;
+    *ids_direct = fh->hdr->huge_ids_direct;
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* H5HF_get_huge_info_test() */
+
diff --git a/src/H5HFtiny.c b/src/H5HFtiny.c
new file mode 100644
index 0000000..5183a39
--- /dev/null
+++ b/src/H5HFtiny.c
@@ -0,0 +1,326 @@
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * 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://hdf.ncsa.uiuc.edu/HDF5/doc/Copyright.html.  If you do not have     *
+ * access to either file, you may request a copy from hdfhelp@ncsa.uiuc.edu. *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+/*-------------------------------------------------------------------------
+ *
+ * Created:		H5HFtiny.c
+ *			Aug 14 2006
+ *			Quincey Koziol <koziol@hdfgroup.org>
+ *
+ * Purpose:		Routines for "tiny" objects in fractal heap
+ *
+ *-------------------------------------------------------------------------
+ */
+
+/****************/
+/* Module Setup */
+/****************/
+
+#define H5HF_PACKAGE		/*suppress error about including H5HFpkg  */
+
+
+/***********/
+/* Headers */
+/***********/
+#include "H5private.h"		/* Generic Functions			*/
+#include "H5Eprivate.h"		/* Error handling		  	*/
+#include "H5HFpkg.h"		/* Fractal heaps			*/
+
+
+/****************/
+/* Local Macros */
+/****************/
+
+/* Tiny object length information */
+#define H5HF_TINY_LEN_SHORT     16              /* Max. length able to be encoded in first heap ID byte */
+#define H5HF_TINY_MASK_SHORT    0x0F            /* Mask for length in first heap ID byte */
+#define H5HF_TINY_MASK_EXT      0x0FFF          /* Mask for length in two heap ID bytes */
+#define H5HF_TINY_MASK_EXT_1    0x0F00          /* Mask for length in first byte of two heap ID bytes */
+#define H5HF_TINY_MASK_EXT_2    0x00FF          /* Mask for length in second byte of two heap ID bytes */
+
+
+/******************/
+/* Local Typedefs */
+/******************/
+
+
+/********************/
+/* Package Typedefs */
+/********************/
+
+
+/********************/
+/* Local Prototypes */
+/********************/
+
+
+/*********************/
+/* Package Variables */
+/*********************/
+
+
+/*****************************/
+/* Library Private Variables */
+/*****************************/
+
+
+/*******************/
+/* Local Variables */
+/*******************/
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_tiny_init
+ *
+ * Purpose:	Initialize information for tracking 'tiny' objects
+ *
+ * Return:	SUCCEED/FAIL
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@hdfgroup.org
+ *		Aug 14 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5HF_tiny_init(H5HF_hdr_t *hdr)
+{
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_tiny_init)
+
+    /*
+     * Check arguments.
+     */
+    HDassert(hdr);
+
+    /* Compute information about 'tiny' objects for the heap */
+
+    /* Check if tiny objects need an extra byte for their length */
+    /* (account for boundary condition when length of an object would need an
+     *  extra byte, but using that byte means that the extra length byte is
+     *  unneccessary)
+     */
+    if((hdr->id_len - 1) <= H5HF_TINY_LEN_SHORT) {
+        hdr->tiny_max_len = hdr->id_len - 1;
+        hdr->tiny_len_extended = FALSE;
+    } /* end if */
+    else if((hdr->id_len - 1) == (H5HF_TINY_LEN_SHORT + 1)) {
+        hdr->tiny_max_len = H5HF_TINY_LEN_SHORT;
+        hdr->tiny_len_extended = FALSE;
+    } /* end if */
+    else {
+        hdr->tiny_max_len = hdr->id_len - 2;
+        hdr->tiny_len_extended = TRUE;
+    } /* end else */
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5HF_tiny_init() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_tiny_insert
+ *
+ * Purpose:	Pack a 'tiny' object in a heap ID
+ *
+ * Return:	SUCCEED/FAIL
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@hdfgroup.org
+ *		Aug 14 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5HF_tiny_insert(H5HF_hdr_t *hdr, size_t obj_size, const void *obj, void *_id)
+{
+    uint8_t *id = (uint8_t *)_id;       /* Pointer to ID buffer */
+    size_t enc_obj_size;                /* Encoded object size */
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT(H5HF_tiny_insert)
+#ifdef QAK
+HDfprintf(stderr, "%s: obj_size = %Zu\n", FUNC, obj_size);
+#endif /* QAK */
+
+    /*
+     * Check arguments.
+     */
+    HDassert(hdr);
+    HDassert(obj_size <= hdr->tiny_max_len);
+    HDassert(obj_size <= (H5HF_TINY_MASK_EXT + 1));
+    HDassert(obj);
+    HDassert(id);
+
+    /* Adjust object's size for encoding it */
+    enc_obj_size = obj_size - 1;
+
+    /* Encode object into ID */
+    if(!hdr->tiny_len_extended) {
+        *id++ = H5HF_ID_VERS_CURR | H5HF_ID_TYPE_TINY |
+                (enc_obj_size & H5HF_TINY_MASK_SHORT);
+    } /* end if */
+    else {
+        *id++ = H5HF_ID_VERS_CURR | H5HF_ID_TYPE_TINY |
+                ((enc_obj_size & H5HF_TINY_MASK_EXT_1) >> 8);
+        *id++ = enc_obj_size & H5HF_TINY_MASK_EXT_2;
+    } /* end else */
+    HDmemcpy(id, obj, obj_size);
+
+    /* Update statistics about heap */
+    hdr->tiny_size += obj_size;
+    hdr->tiny_nobjs++;
+
+    /* Mark heap header as modified */
+    if(H5HF_hdr_dirty(hdr) < 0)
+        HGOTO_ERROR(H5E_HEAP, H5E_CANTDIRTY, FAIL, "can't mark heap header as dirty")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5HF_tiny_insert() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_tiny_get_obj_len
+ *
+ * Purpose:	Get the size of a 'tiny' object in a fractal heap
+ *
+ * Return:	SUCCEED/FAIL
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@hdfgroup.org
+ *		Aug 14 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5HF_tiny_get_obj_len(H5HF_hdr_t *hdr, const uint8_t *id, size_t *obj_len_p)
+{
+    size_t enc_obj_size;                /* Encoded object size */
+
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_tiny_get_obj_len)
+
+    /*
+     * Check arguments.
+     */
+    HDassert(hdr);
+    HDassert(id);
+    HDassert(obj_len_p);
+
+    /* Check if 'tiny' object ID is in extended form, and retrieve encoded size */
+    if(!hdr->tiny_len_extended)
+        enc_obj_size = *id & H5HF_TINY_MASK_SHORT;
+    else
+        enc_obj_size = ((*id & H5HF_TINY_MASK_EXT_1) << 8) | (*(id + 1) & H5HF_TINY_MASK_EXT_2);
+
+    /* Set the object's length */
+    *obj_len_p = enc_obj_size + 1;
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5HF_tiny_get_obj_len() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_tiny_read
+ *
+ * Purpose:	Read a 'tiny' object from the heap
+ *
+ * Return:	SUCCEED/FAIL
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@hdfgroup.org
+ *		Aug  8 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5HF_tiny_read(H5HF_hdr_t *hdr, const uint8_t *id, void *obj)
+{
+    size_t enc_obj_size;                /* Encoded object size */
+
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_tiny_read)
+
+    /*
+     * Check arguments.
+     */
+    HDassert(hdr);
+    HDassert(id);
+    HDassert(obj);
+
+    /* Check if 'tiny' object ID is in extended form */
+    if(!hdr->tiny_len_extended) {
+        /* Retrieve the object's encoded length */
+        enc_obj_size = *id & H5HF_TINY_MASK_SHORT;
+
+        /* Advance past flag byte(s) */
+        id++;
+    } /* end if */
+    else {
+        /* Retrieve the object's encoded length */
+        enc_obj_size = ((*id & H5HF_TINY_MASK_EXT_1) << 8) | (*(id + 1) & H5HF_TINY_MASK_EXT_2);
+
+        /* Advance past flag byte(s) */
+        id+=2;
+    } /* end else */
+
+    /* Retrieve the object's data */
+    HDmemcpy(obj, id, (enc_obj_size + 1));
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5HF_tiny_read() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_tiny_remove
+ *
+ * Purpose:	Remove a 'tiny' object from the heap statistics
+ *
+ * Return:	SUCCEED/FAIL
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@hdfgroup.org
+ *		Aug 14 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5HF_tiny_remove(H5HF_hdr_t *hdr, const uint8_t *id)
+{
+    size_t enc_obj_size;                /* Encoded object size */
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT(H5HF_tiny_remove)
+
+    /*
+     * Check arguments.
+     */
+    HDassert(hdr);
+    HDassert(id);
+
+    /* Check if 'tiny' object ID is in extended form */
+    if(!hdr->tiny_len_extended)
+        enc_obj_size = *id & H5HF_TINY_MASK_SHORT;
+    else
+        enc_obj_size = ((*id & H5HF_TINY_MASK_EXT_1) << 8) | (*(id + 1) & H5HF_TINY_MASK_EXT_2);
+
+    /* Update statistics about heap */
+    hdr->tiny_size -= (enc_obj_size + 1);
+    hdr->tiny_nobjs--;
+
+    /* Mark heap header as modified */
+    if(H5HF_hdr_dirty(hdr) < 0)
+        HGOTO_ERROR(H5E_HEAP, H5E_CANTDIRTY, FAIL, "can't mark heap header as dirty")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5HF_tiny_remove() */
+
diff --git a/src/Makefile.am b/src/Makefile.am
index 4d464bb..86ce039 100755
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -53,7 +53,7 @@ libhdf5_la_SOURCES= H5.c H5dbg.c H5A.c H5AC.c H5B.c H5Bcache.c \
         H5Gobj.c H5Goh.c H5Gstab.c H5Gtest.c H5Gtraverse.c  \
         H5HF.c H5HFbtree2.c H5HFcache.c H5HFdbg.c H5HFdblock.c H5HFdtable.c \
         H5HFhdr.c H5HFhuge.c H5HFiblock.c H5HFiter.c H5HFman.c H5HFsection.c \
-        H5HFspace.c H5HFstat.c H5HFtest.c \
+        H5HFspace.c H5HFstat.c H5HFtest.c H5HFtiny.c \
         H5HG.c H5HGdbg.c H5HL.c H5HLdbg.c H5HP.c H5I.c H5MF.c H5MM.c \
         H5MP.c H5MPtest.c H5L.c H5Lexternal.c H5O.c H5Oattr.c H5Obogus.c H5Ocache.c \
         H5Ocont.c H5Odtype.c H5Oefl.c H5Ofill.c H5Oginfo.c H5Olayout.c \
diff --git a/src/Makefile.in b/src/Makefile.in
index 990023b..6b5d981 100644
--- a/src/Makefile.in
+++ b/src/Makefile.in
@@ -96,9 +96,9 @@ am_libhdf5_la_OBJECTS = H5.lo H5dbg.lo H5A.lo H5AC.lo H5B.lo \
 	H5Gtest.lo H5Gtraverse.lo H5HF.lo H5HFbtree2.lo H5HFcache.lo \
 	H5HFdbg.lo H5HFdblock.lo H5HFdtable.lo H5HFhdr.lo H5HFhuge.lo \
 	H5HFiblock.lo H5HFiter.lo H5HFman.lo H5HFsection.lo \
-	H5HFspace.lo H5HFstat.lo H5HFtest.lo H5HG.lo H5HGdbg.lo \
-	H5HL.lo H5HLdbg.lo H5HP.lo H5I.lo H5MF.lo H5MM.lo H5MP.lo \
-	H5MPtest.lo H5L.lo H5Lexternal.lo H5O.lo H5Oattr.lo \
+	H5HFspace.lo H5HFstat.lo H5HFtest.lo H5HFtiny.lo H5HG.lo \
+	H5HGdbg.lo H5HL.lo H5HLdbg.lo H5HP.lo H5I.lo H5MF.lo H5MM.lo \
+	H5MP.lo H5MPtest.lo H5L.lo H5Lexternal.lo H5O.lo H5Oattr.lo \
 	H5Obogus.lo H5Ocache.lo H5Ocont.lo H5Odtype.lo H5Oefl.lo \
 	H5Ofill.lo H5Oginfo.lo H5Olayout.lo H5Olinfo.lo H5Olink.lo \
 	H5Omtime.lo H5Oname.lo H5Onull.lo H5Opline.lo H5Osdspace.lo \
@@ -402,7 +402,7 @@ libhdf5_la_SOURCES = H5.c H5dbg.c H5A.c H5AC.c H5B.c H5Bcache.c \
         H5Gobj.c H5Goh.c H5Gstab.c H5Gtest.c H5Gtraverse.c  \
         H5HF.c H5HFbtree2.c H5HFcache.c H5HFdbg.c H5HFdblock.c H5HFdtable.c \
         H5HFhdr.c H5HFhuge.c H5HFiblock.c H5HFiter.c H5HFman.c H5HFsection.c \
-        H5HFspace.c H5HFstat.c H5HFtest.c \
+        H5HFspace.c H5HFstat.c H5HFtest.c H5HFtiny.c \
         H5HG.c H5HGdbg.c H5HL.c H5HLdbg.c H5HP.c H5I.c H5MF.c H5MM.c \
         H5MP.c H5MPtest.c H5L.c H5Lexternal.c H5O.c H5Oattr.c H5Obogus.c H5Ocache.c \
         H5Ocont.c H5Odtype.c H5Oefl.c H5Ofill.c H5Oginfo.c H5Olayout.c \
@@ -624,6 +624,7 @@ distclean-compile:
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5HFspace.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5HFstat.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5HFtest.Plo@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5HFtiny.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5HG.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5HGdbg.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5HL.Plo@am__quote@