[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, 18 insertions, 6 deletions

diff --git a/src/H5FDmulti.c b/src/H5FDmulti.c
index 9a9667e..45ee689 100644
--- a/src/H5FDmulti.c
+++ b/src/H5FDmulti.c
@@ -417,7 +417,7 @@ H5Pset_fapl_multi(hid_t fapl_id, const H5FD_mem_t *memb_map,
     }
     if (!memb_fapl) {
 	for (mt=H5FD_MEM_DEFAULT; mt<H5FD_MEM_NTYPES; mt=(H5FD_mem_t)(mt+1)) {
-	    _memb_fapl[mt] = H5P_DEFAULT;
+	    _memb_fapl[mt] = H5Pcreate(H5P_FILE_ACCESS);
 	}
 	memb_fapl = _memb_fapl;
     }
@@ -464,6 +464,12 @@ H5Pset_fapl_multi(hid_t fapl_id, const H5FD_mem_t *memb_map,
     memcpy(fa.memb_name, memb_name, H5FD_MEM_NTYPES*sizeof(char*));
     memcpy(fa.memb_addr, memb_addr, H5FD_MEM_NTYPES*sizeof(haddr_t));
     fa.relax = relax;
+
+    /* Patch up H5P_DEFAULT property lists for members */
+    for (mt=H5FD_MEM_DEFAULT; mt<H5FD_MEM_NTYPES; mt=(H5FD_mem_t)(mt+1)) {
+        if(fa.memb_fapl[mt]==H5P_DEFAULT)
+            fa.memb_fapl[mt] = H5Pcreate(H5P_FILE_ACCESS);
+    }
     return H5Pset_driver(fapl_id, H5FD_MULTI, &fa);
 }
 
@@ -581,13 +587,19 @@ H5Pset_dxpl_multi(hid_t dxpl_id, const hid_t *memb_dxpl)
     if (!memb_dxpl)
         H5Epush_ret(func, H5E_INTERNAL, H5E_BADVALUE, "invalid pointer", -1);
     for (mt=H5FD_MEM_DEFAULT; mt<H5FD_MEM_NTYPES; mt=(H5FD_mem_t)(mt+1)) {
-	if (H5P_DEFAULT!=memb_dxpl[mt] &&
-            TRUE!=H5Pisa_class(memb_dxpl[mt], H5P_DATASET_XFER))
+        if (memb_dxpl[mt]!=H5P_DEFAULT && TRUE!=H5Pisa_class(memb_dxpl[mt], H5P_DATASET_XFER))
             H5Epush_ret(func, H5E_PLIST, H5E_BADTYPE, "not a data transfer property list", -1);
     }
 
     /* Initialize the data transfer property list */
     memcpy(dx.memb_dxpl, memb_dxpl, H5FD_MEM_NTYPES*sizeof(hid_t));
+
+    /* Convert "generic" default property lists into default dataset transfer property lists */
+    for (mt=H5FD_MEM_DEFAULT; mt<H5FD_MEM_NTYPES; mt=(H5FD_mem_t)(mt+1)) {
+        if (dx.memb_dxpl[mt]==H5P_DEFAULT)
+            dx.memb_dxpl[mt]=H5P_DATASET_XFER_DEFAULT;
+    }
+
     return H5Pset_driver(dxpl_id, H5FD_MULTI, &dx);
 }
 
@@ -1173,7 +1185,7 @@ H5FD_multi_open(const char *name, unsigned flags, hid_t fapl_id,
      */
     if (NULL==(file=calloc(1, sizeof(H5FD_multi_t))))
         H5Epush_ret(func, H5E_RESOURCE, H5E_NOSPACE, "memory allocation failed", NULL);
-    if (H5P_DEFAULT==fapl_id || H5FD_MULTI!=H5Pget_driver(fapl_id)) {
+    if (H5P_FILE_ACCESS_DEFAULT==fapl_id || H5FD_MULTI!=H5Pget_driver(fapl_id)) {
         close_fapl = fapl_id = H5Pcreate(H5P_FILE_ACCESS);
         H5Pset_fapl_multi(fapl_id, NULL, NULL, NULL, NULL, TRUE);
     }
@@ -1652,7 +1664,7 @@ H5FD_multi_read(H5FD_t *_file, H5FD_mem_t type, hid_t dxpl_id, haddr_t addr, siz
     H5Eclear();
 
     /* Get the data transfer properties */
-    if (H5P_DEFAULT!=dxpl_id && H5FD_MULTI==H5Pget_driver(dxpl_id)) {
+    if (H5P_FILE_ACCESS_DEFAULT!=dxpl_id && H5FD_MULTI==H5Pget_driver(dxpl_id)) {
 	dx = H5Pget_driver_info(dxpl_id);
     }
     
@@ -1707,7 +1719,7 @@ H5FD_multi_write(H5FD_t *_file, H5FD_mem_t type, hid_t dxpl_id, haddr_t addr, si
     H5Eclear();
 
     /* Get the data transfer properties */
-    if (H5P_DEFAULT!=dxpl_id && H5FD_MULTI==H5Pget_driver(dxpl_id)) {
+    if (H5P_FILE_ACCESS_DEFAULT!=dxpl_id && H5FD_MULTI==H5Pget_driver(dxpl_id)) {
 	dx = H5Pget_driver_info(dxpl_id);
     }