[svn-r6252] Purpose:

    Lots of performance improvements & a couple new internal API interfaces.

Description:
    Performance Improvements:
        - Cached file offset & length sizes in shared file struct, to avoid
            constantly looking them up in the FCPL.
        - Generic property improvements:
            - Added "revision" number to generic property classes to speed
                up comparisons.
            - Changed method of storing properties from using a hash-table
                to the TBBT routines in the library.
            - Share the propery names between classes and the lists derived
                from them.
            - Removed redundant 'def_value' buffer from each property.
            - Switching code to use a "copy on write" strategy for
                properties in each list, where the properties in each list
                are shared with the properties in the class, until a
                property's value is changed in a list.
        - Fixed error in layout code which was allocating too many buffers.
        - Redefined public macros of the form (H5open()/H5check, <variable>)
            internally to only be (<variable>), avoiding innumerable useless
            calls to H5open() and H5check_version().
        - Reuse already zeroed buffers in H5F_contig_fill instead of
            constantly re-zeroing them.
        - Don't write fill values if writing entire dataset.
        - Use gettimeofday() system call instead of time() system when
            checking the modification time of a dataset.
        - Added reference counted string API and use it for tracking the
            names of objects opening in a file (for the ID->name code).
        - Removed redundant H5P_get() calls in B-tree routines.
        - Redefine H5T datatype macros internally to the library, to avoid
            calling H5check redundantly.
        - Keep dataspace information for dataset locally instead of reading
            from disk each time.  Added new module to track open objects
            in a file, to allow this (which will be useful eventually for
            some FPH5 metadata caching issues).
        - Remove H5AC_find macro which was inlining metadata cache lookups,
            and call function instead.
        - Remove redundant memset() calls from H5G_namei() routine.
        - Remove redundant checking of object type when locating objects
            in metadata cache and rely on the address only.
        - Create default dataset object to use when default dataset creation
            property list is used to create datasets, bypassing querying
            for all the property list values.
        - Use default I/O vector size when performing raw data with the
            default dataset transfer property list, instead of querying for
            I/O vector size.
        - Remove H5P_DEFAULT internally to the library, replacing it with
            more specific default property list based on the type of
            property list needed.
        - Remove redundant memset() calls in object header message (H5O*)
            routines.
        - Remove redunant memset() calls in data I/O routines.
        - Split free-list allocation routines into malloc() and calloc()-
            like routines, instead of one combined routine.
        - Remove lots of indirection in H5O*() routines.
        - Simplify metadata cache entry comparison routine (used when
            flushing entire cache out).
        - Only enable metadata cache statistics when H5AC_DEBUG is turned
            on, instead of always tracking them.
        - Simplify address comparison macro (H5F_addr_eq).
        - Remove redundant metadata cache entry protections during dataset
            creation by protecting the object header once and making all
            the modifications necessary for the dataset creation before
            unprotecting it.
        - Reduce # of "number of element in extent" computations performed
            by computing and storing the value during dataspace creation.
        - Simplify checking for group location's file information, when file
            has not been involving in file-mounting operations.
        - Use binary encoding for modification time, instead of ASCII.
        - Hoist H5HL_peek calls (to get information in a local heap)
            out of loops in many group routine.
        - Use static variable for iterators of selections, instead of
            dynamically allocation them each time.
        - Lookup & insert new entries in one step, avoiding traversing
            group's B-tree twice.
        - Fixed memory leak in H5Gget_objname_idx() routine (tangential to
            performance improvements, but fixed along the way).
        - Use free-list for reference counted strings.
        - Don't bother copying object names into cached group entries,
            since they are re-created when an object is opened.

        The benchmark I used to measure these results created several thousand
        small (2K) datasets in a file and wrote out the data for them.  This is
        Elena's "regular.c" benchmark.

        These changes resulted in approximately ~4.3x speedup of the
        development branch when compared to the previous code in the
        development branch and ~1.4x speedup compared to the release
        branch.

        Additionally, these changes reduce the total memory used (code and
        data) by the development branch by ~800KB, bringing the development
        branch back into the same ballpark as the release branch.

        I'll send out a more detailed description of the benchmark results
        as a followup note.

    New internal API routines:
        Added "reference counted strings" API for tracking strings that get
            used by multiple owners without duplicating the strings.
        Added "ternary search tree" API for text->object mappings.

Platforms tested:
    Tested h5committest {arabica (fortran), eirene (fortran, C++)
	modi4 (parallel, fortran)}
    Other platforms/configurations tested?
        FreeBSD 4.7 (sleipnir) serial & parallel
        Solaris 2.6 (baldric) serial

1 files changed, 5 insertions, 5 deletions

diff --git a/src/H5A.c b/src/H5A.c
index 8f7f0bb..ab180d2 100644
--- a/src/H5A.c
+++ b/src/H5A.c
@@ -275,7 +275,7 @@ H5A_create(const H5G_entry_t *ent, const char *name, const H5T_t *type,
     H5E_clear ();
 
     /* Create the attribute message and save the attribute index */
-    if (H5O_modify(&(attr->ent), H5O_ATTR, H5O_NEW_MESG, 0, attr) < 0) 
+    if (H5O_modify(&(attr->ent), H5O_ATTR, H5O_NEW_MESG, 0, 1, attr) < 0) 
         HGOTO_ERROR(H5E_ATTR, H5E_CANTINIT, FAIL, "unable to update attribute header messages");
 
     /* Register the new attribute and get an ID for it */
@@ -635,7 +635,7 @@ H5A_write(H5A_t *attr, const H5T_t *mem_type, const void *buf)
 
     /* Perform data type conversion */
     if (H5T_convert(tpath, src_id, dst_id, nelmts, 0, 0, tconv_buf, bkg_buf,
-                    H5P_DEFAULT)<0) {
+                    H5P_DATASET_XFER_DEFAULT)<0) {
         HGOTO_ERROR(H5E_ATTR, H5E_CANTENCODE, FAIL,
 		    "data type conversion failed");
     }
@@ -650,7 +650,7 @@ H5A_write(H5A_t *attr, const H5T_t *mem_type, const void *buf)
 
     /* Modify the attribute data */
     attr->data=tconv_buf;   /* Set the data pointer temporarily */
-    if (H5O_modify(&(attr->ent), H5O_ATTR, idx, 0, attr) < 0) 
+    if (H5O_modify(&(attr->ent), H5O_ATTR, idx, 0, 1, attr) < 0) 
         HGOTO_ERROR(H5E_ATTR, H5E_CANTINIT, FAIL,
 		    "unable to update attribute header messages");
 
@@ -787,7 +787,7 @@ H5A_read(H5A_t *attr, const H5T_t *mem_type, void *buf)
         }
 
         /* Perform data type conversion.  */
-        if (H5T_convert(tpath, src_id, dst_id, nelmts, 0, 0, tconv_buf, bkg_buf, H5P_DEFAULT)<0)
+        if (H5T_convert(tpath, src_id, dst_id, nelmts, 0, 0, tconv_buf, bkg_buf, H5P_DATASET_XFER_DEFAULT)<0)
             HGOTO_ERROR(H5E_ATTR, H5E_CANTENCODE, FAIL, "data type conversion failed");
 
         /* Copy the converted data into the user's buffer */
@@ -1223,7 +1223,7 @@ H5A_rename(H5G_entry_t *ent, const char *old_name, const char *new_name)
     found_attr->initialized=TRUE;
 
     /* Modify the attribute message */
-    if (H5O_modify(ent, H5O_ATTR, idx, 0, found_attr) < 0) 
+    if (H5O_modify(ent, H5O_ATTR, idx, 0, 1, found_attr) < 0) 
         HGOTO_ERROR(H5E_ATTR, H5E_CANTINIT, FAIL, "unable to update attribute header messages");
    
     /* Close the attribute */