mirror/hdf5
2
0
Fork 0
mirror of https://github.com/HDFGroup/hdf5.git synced 2024-12-03 02:32:04 +08:00
Code Issues Packages Projects Releases Wiki Activity

[svn-r655] Changed H5F_low_write's treatment of eof in nonblock parallel writes.

Browse Source
This commit is contained in:
Robert Kim Yates 1998-09-02 16:52:25 -05:00
parent 97f56b57a0
commit 07f1057ec7
1 changed files with 13 additions and 21 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

34
src/H5Flow.c
View File

@ -271,6 +271,9 @@ H5F_low_read(H5F_low_t *lf, const H5F_access_t *access_parms,
*
* rky 980816
* Accommodate fancy MPI derived datatype writes.
*
* rky 980902
* For non-block parallel writes, don't change value of lf->eof.
*-------------------------------------------------------------------------
*/
herr_t
@ -281,10 +284,6 @@ H5F_low_write(H5F_low_t *lf, const H5F_access_t *access_parms,
herr_t ret_value = FAIL;
haddr_t tmp_addr;
#ifdef HAVE_PARALLEL
int use_types=0;
#endif
FUNC_ENTER(H5F_low_write, FAIL);
assert(lf && lf->type);
@ -295,14 +294,20 @@ H5F_low_write(H5F_low_t *lf, const H5F_access_t *access_parms,
#ifdef HAVE_PARALLEL
if (H5F_LOW_MPIO==access_parms->driver &&
access_parms->u.mpio.use_types) {
/* In the case of fancy use of MPI datatypes, the addr and size
/* rky 090902 KLUGE
* In the case of fancy use of MPI datatypes, the addr and size
* parameters have a very peculiar interpretation.
* It is logically possible, but quite complex, to calculate
* the physical offset that the last byte to be written will have
* (assuming the write doesn't fail partway thru, which it may).
* Instead, we fix up the eof _after_ the write
* (I really don't know if that's OK or not... rky 980816) */
use_types = access_parms->u.mpio.use_types; /* check after write */
* I don't yet fully understand the relationship between
* the lf->eof processor-local variable and the file's true eof.
* But presumably lf->eof has the correct value at this point,
* and we should _not_ change it,
* even if the file's true eof differs from the value of lf->eof.
* So for now we DO NOTHING!
* (Eventually, perhaps we should at least calculate the address
* of the last byte of this write, and compare it to lf->eof.) */
} else {
#endif /* HAVE_PARALLEL */
/* writing a simple block of bytes; can check for writing beyond eof */
@ -330,19 +335,6 @@ H5F_low_write(H5F_low_t *lf, const H5F_access_t *access_parms,
HRETURN_ERROR(H5E_IO, H5E_UNSUPPORTED, FAIL, "no write method");
}
#ifdef HAVE_PARALLEL
/* fix up eof for MPI use_type writes */
if (H5F_LOW_MPIO==access_parms->driver && use_types) {
/* set logical eof to current physical eof
* (ephemeral though it may be...) */
MPI_Offset mpi_offset_size;
if (MPI_SUCCESS != MPI_File_get_size(lf->u.mpio.f,&mpi_offset_size)) {
HRETURN_ERROR(H5E_IO, H5E_MPI, FAIL, "couldn't get file size" );
}
lf->eof.offset = mpi_offset_size;
}
#endif
FUNC_LEAVE(ret_value);
}