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
Purpose:
add "shuffle" filter note
Description:
Solution:
Platforms tested:
Misc. update:
Update MANIFEST if you add or remove any file.
Update release_docs/RELEASE for bug fixes, new features, etc.
Update applicable document files too.
Purpose:
New function.
Description:
H5Dget_offset returns the offset of a dataset's data relative to the
beginning of a file.
Platforms tested:
arabica(simple function, one test should be enough.)
Misc. update:
RELEASE.txt
New feature
Description:
Add support for scalar dataspaces in parallel I/O.
Platforms tested:
Tested h5committest {arabica (fortran), eirene (fortran, C++)
modi4 (parallel, fortran)}
Also, FreeBSD 4.7 (sleipnir) serial & parallel
Misc. update:
Update release_docs/RELEASE for bug fixes, new features, etc.
Purpose:
Change release note for new functions(H5Gget_comment, H5Arename,
H5Aget_storage_size).
Misc. update:
Update release_docs/RELEASE for bug fixes, new features, etc.
Purpose:
Added missing fortran functions h5set(get)_buffer_f.
Also added docs and tests for them.
Solution:
Currently functions do not accept conversion and background buffers.
This corresponds to H5set(get)_buffer call with buffer pointers
set to NULL. If there is a demand, I can overload the functions
to have new parameters and go through all trouble creating functions
for all supported datatypes.
Platforms tested:
Solaris 2.7, Linux 2.2., IRIX64-6.5
Purpose:
Added new F90 APIs
Description:
I added new F90 APIs, tests, and documentation for the following
functions:
h5fget_obj_count_f h5pequal_f h5tget_member_index_f
h5fget_obj_ids_f h5pget_fclose_degree_f
h5pset_fclose_degree_f
Documentation for exisiting functions was missing:
h5freopen_f, h5fflush_f, h5fmount_f, h5unmount_f, h5fget_create_plist_f,
h5fget_access_plist_f.
Platforms tested:
Solaris 2.7, Linux 2.2 and IRIX64-6.5
Purpose:
New API functions
Description:
Added API functions to return pointer to low-level file handle
(H5Fget_vfd_handle and H5FDget_vfd_handle) and related property list
setting functions(H5Pset_family_offset and H5Pset_multi_type).
Platforms tested:
Linux 2.2(eirene), Solaris 2.7(arabica), IRIX64 6.5(modi4)
Purpose:
Added new fortran functions
Description:
Source code, tests and documentation for h5glink2_f and h5gmove2_f
functions were added. I also added missing man page for h5glink_f
Platforms tested:
Solaris 2.7, IRIX64-6.5 and Liniux 2.2
Purpose:
Added missing fortran functions.
Description:
Four Library Fortran API functions have been added:
h5get_libversion_f, h5_check_version_f, h5garbage_collect_f and
h5dont_atexit_f. Only first two functions were tested.
Documentation file and RELEASE.txt were updated.
Platforms tested:
Solaris 2.7, IRIX64-6.5 and Linux 2.2
API name change
Description:
Change all "space time" references to "alloc time", including API functions
and macro definitions, etc.
Platforms tested:
FreeBSD 4.6 (sleipnir) w/C++
Solaris 2.7 (arabica) w/FORTRAN
IRIX64 6.5 (modi4) w/parallel & FORTRAN
Code cleanup/New Feature
Description:
Improve the space allocation in the file by re-using freed space more
effectively.
Platforms tested:
FreeBSD 4.6 (sleipnir) w/serial & parallel
Purpose:
Merged from 1.4 branch
Description:
API tracing improvements
Platforms tested:
Linux (--disable-hsizet didn't work before my changes and still doesn't
work, but --enable-hsizet is fine).
Note: This checkin includes temporary code in H5FDmpiposix.c to turn
off GPFS byte range token prefetches on ASCI/Blue. Once the HDF5 API
supports the necessary prerequisite functionality this temporary code
can be migraged up above HDF5.
Purpose:
update windows support.
Description:
1. Since we don't support w98 anymore, delete the description about w98.
Actually DLL may work on w98.
2. Release dll work for new HDF5 release.
Solution:
Platforms tested:
Bug Fix
Description:
It was possible to create corrupted metadata information (either in memory
or in the file or both) with a parallel I/O program because of the way
metadata writes were being handled for writes out of the metadata cache.
Solution:
Added a dataset transfer property called "block before metadata write"
which is used by the MPI-I/O and MPI-posix drivers to sync up all the
processes before attempting a metadata write. This property is currently
only for metadata writes from the metadata cache.
Platforms tested:
IRIX64 6.5 (modi4) w/parallel
Bug Fix
Description:
When parallel I/O is used, the MPI-I/O VFL driver uses a "lazy" model to
call MPI_File_set_view() in order to reduce the number of calls to this
function. However, this is unsafe, because if a collective I/O which uses
MPI derived types (and thus uses MPI_File_set_view()) is immediately
followed by an independent I/O, the code will attempt to call
MPI_File_set_view() in order to switch back to the default view of the
file. MPI_File_set_view() is a collective call however, and this causes
the application to hang.
Solution:
Removed "lazy" MPI_File_set_view() code, instead set the file view when it
is needed (with MPI derived types) and immediately set the file view back to
the default view before leaving the I/O routine.
Platforms tested:
IRIX64 6.5 (modi4) w/parallel. Also, tested with the latest development
and release code for the SAF library, which now works correctly with this
change. (Although the release branch of the SAF library seems to have a
bug, this 1.4.4 release candidate code gets as far as the version the SAF
library is released on top of (1.4.2-patch1, I believe)).
