Code cleanup
Description:
Add destructor to match constructor fr VFLs when they are shut down by the
library.
Solution:
Added H5FD_*_term() routines to "undo" changes made in H5FD_*_init()
routines.
Platforms tested:
IBM p690 (copper)
too minor to require h5committest
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:
__DLL__ is a keyword in some platforms and __DLL__ is also defined as a macro for windows DLL applications.
That causes problems.
Description:
Solution:
Use H5_DLL*** to replace __DLL***__ at all header files.
Change the macro defination at H5api_adpt.h.
Platforms tested:
linux2.2.18smp, irix64, solaris 2.7 and windows 2000
Backward Compatibility Fix
Description:
H5Pset_fapl_log's parameters have changed from a simple "verbosity" level
to bit-masked flags to enable various behaviors.
Solution:
Added in v1.4 compat stuff, on the unlikely chance that others are actually
using this code in some production way.
There are no C++ or FORTRAN wrappers for this call.
Platforms tested:
FreeBSD 4.4 (hawkwind)
Code cleanup
Description:
Changed the logging file driver to use bitmasked flags for features to
enable, instead of using a verbosity level.
Platforms tested:
Solaris 2.6 (baldric)
Purpose:
Bug Fix
Description:
Forward port of the bug fix to the 1.4 branch reguarding the C++
compile error.
Solution:
Need to put
#ifdef __cplusplus
extern "C" {
#endif
/* ... */
#ifdef __cplusplus
}
#endif
around function declarations.
Document bug fix
Description:
IMPORTANT! IMPORTANT! IMPORTANT!
A case where metadata in a file could get corrupted in certain unusual
sitations was detected and fixed.
In certain circumstances, metadata could get cached in the raw data cache,
and if that particular piece of metadata was updated on disk while
incorrectly cached, the new metadata would get overwritten with the stale
metadata from the raw data cache when it was flushed out.
Additionally, I've patched up the raw data cache to be smarter about how
much it caches and how much I/O it triggers, leading to some speedups.
Solution:
Changed the raw data I/O routines which perform caching to require a
parameter with the size of the dataset being accessed and limited the
cache to no more than that many bytes.
Platforms tested:
FreeBSD 4.3 (hawkwind)
Update
Description:
Changed
#include <hdf_file.h>
construct to
#include "hdf_file.h"
so that the GNU compiler can more easily pick up the dependencies
which it places in the .depend and Dependencies files. Also
regenerated the Dependencies to go along with this.
Platforms tested:
Linux
Maintainance & performance enhancements
Description:
Re-arranged header files to protect private symbols better.
Changed optimized regular hyperslab I/O to compute the offsets more
efficiently from previous method of using matrix operations.
Added sequential I/O operations at a more abstract level (at the same level
as H5F_arr_read/write), to support the optimized hyperslab I/O.
Platforms tested:
Solaris 2.6 (baldric) & FreeBSD 4.1.1 (hawkwind)
