[svn-r13477] Description:

		The main purpose of this checkin was to eliminate the
space used for tracking creation time indices when there is no way they
can be used (i.e. attributes can't be shared in the file and the user hasn't
turned on attribute creation tracking), however there were some other minor
changes which crept in:
	- Fix a cache locking deadlock when a shared attribute and one of its
		components end up in the same fractal heap direct block.  
		(This is fixed the "slow" way for right now, until John has time
		to add support for readers/writer locking to the cache.
	- Optimize attribute copying when a copy will be kept during a v2 B-tree
		search.
	- When freeing a block on disk, attempt to merge it with the metadata
		and "small data" aggregators.

Tested on:
	Mac OS X/32 10.4.8 (amazon)
	FreeBSD/32 6.2 (duty)

1 files changed, 13 insertions, 4 deletions

diff --git a/src/H5O.c b/src/H5O.c
index f4dd5d9..0741621 100644
--- a/src/H5O.c
+++ b/src/H5O.c
@@ -634,9 +634,10 @@ herr_t
 H5O_create(H5F_t *f, hid_t dxpl_id, size_t size_hint, hid_t ocpl_id,
     H5O_loc_t *loc/*out*/)
 {
-    H5O_t      *oh = NULL;
+    H5O_t      *oh = NULL;              /* Object header created */
     haddr_t     oh_addr;                /* Address of initial object header */
     size_t      oh_size;                /* Size of initial object header */
+    hbool_t     store_msg_crt_idx;      /* Whether to always store message creation indices for this file */
     herr_t      ret_value = SUCCEED;    /* return value */
 
     FUNC_ENTER_NOAPI(H5O_create, FAIL)
@@ -653,8 +654,12 @@ H5O_create(H5F_t *f, hid_t dxpl_id, size_t size_hint, hid_t ocpl_id,
     if(NULL == (oh = H5FL_CALLOC(H5O_t)))
         HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed")
 
-    /* Initialize rudimentary information object object header */
-    oh->version = H5F_USE_LATEST_FORMAT(f) ? H5O_VERSION_LATEST : H5O_VERSION_1;
+    /* Initialize file-specific information for object header */
+    store_msg_crt_idx = H5F_STORE_MSG_CRT_IDX(f);
+    if(H5F_USE_LATEST_FORMAT(f) || store_msg_crt_idx)
+        oh->version = H5O_VERSION_LATEST;
+    else
+        oh->version = H5O_VERSION_1;
     oh->sizeof_size = H5F_SIZEOF_SIZE(f);
     oh->sizeof_addr = H5F_SIZEOF_ADDR(f);
 
@@ -676,7 +681,11 @@ H5O_create(H5F_t *f, hid_t dxpl_id, size_t size_hint, hid_t ocpl_id,
         else
             oh->atime = oh->mtime = oh->ctime = oh->btime = 0;
 
-        /* Initialize attribute tracking fields */
+        /* Make certain attribute creation order tracking is enabled if
+         *      attributes can be shared in this file.
+         */
+        if(store_msg_crt_idx)
+            oh->flags |= H5O_HDR_ATTR_CRT_ORDER_TRACKED;
 
         /* Retrieve attribute storage phase change values from property list */
         if(H5P_get(oc_plist, H5O_CRT_ATTR_MAX_COMPACT_NAME, &oh->max_compact) < 0)