9a433b99a5
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
67 lines
1.5 KiB
C
67 lines
1.5 KiB
C
/*
|
||
* Copyright (C) 2003 NCSA
|
||
* All rights reserved.
|
||
*
|
||
* Programmer: Quincey Koziol <koziol@ncsa.uiuc.edu>
|
||
* Friday, January 3, 2003
|
||
*
|
||
* Purpose: Create a dataset, which should have the older mtime information
|
||
* stored in it.
|
||
* This program is used to create the test file `tmtimeo.h5' which
|
||
* has the new format for mtime information.
|
||
* To build the test file, this program MUST be compiled and linked with
|
||
* the hdf5-1.4+ series of libraries and the generated test file must be
|
||
* put into the 'test' directory in the 1.5+ branch of the library.
|
||
*/
|
||
|
||
#include "hdf5.h"
|
||
|
||
#define TESTFILE "tmtimeo.h5"
|
||
|
||
|
||
/*-------------------------------------------------------------------------
|
||
* Function: main
|
||
*
|
||
* Purpose:
|
||
*
|
||
* Return: Success:
|
||
*
|
||
* Failure:
|
||
*
|
||
* Programmer: Quincey Koziol
|
||
* Friday, January 3, 2003
|
||
*
|
||
* Modifications:
|
||
*
|
||
*-------------------------------------------------------------------------
|
||
*/
|
||
int
|
||
main(void)
|
||
{
|
||
hid_t file, space, dset;
|
||
|
||
/* Create the file */
|
||
file = H5Fcreate(TESTFILE, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
|
||
if(file<0)
|
||
printf("file<0!\n");
|
||
|
||
/* Create the dataspace (for dataset) */
|
||
space = H5Screate(H5S_SCALAR);
|
||
if(space<0)
|
||
printf("space<0!\n");
|
||
|
||
/* Create the dataset with compound array fields */
|
||
dset = H5Dcreate(file, "Dataset1", H5T_NATIVE_INT, space, H5P_DEFAULT);
|
||
if(dset<0)
|
||
printf("dset<0!\n");
|
||
|
||
H5Dclose(dset);
|
||
H5Sclose(space);
|
||
H5Fclose(file);
|
||
|
||
return 0;
|
||
}
|
||
|
||
|
||
|