H5Pset_fapl_mpiposix
(
hid_t fapl_id
,
MPI_Comm comm
,
hbool_t use_gpfs_hints
)
H5Pset_fapl_mpiposix
stores the user-supplied
MPI IO parameter comm
, for communicator,
in the file access property list fapl_id
.
That property list can then be used to create and/or open the file.
H5Pset_fapl_mpiposix
is available only in the
parallel HDF5 library and is not a collective function.
comm
is the MPI communicator to be used for
file open, as defined in MPI_FILE_OPEN
of MPI-2.
This function does not create a duplicated communicator.
Modifications to comm
after this function call
returns may have an undetermined effect on the
file access property list.
Users should not modify the communicator while it is defined
in a property list.
use_gpfs_hints
specifies whether to attempt to use
GPFS hints when accessing this file.
A value of TRUE
(or 1
) indicates that
the hints should be used, if possible.
A value of FALSE
(or 0
) indicates that
the hints should not be used.
Available GPFS hints are known to the HFD5 Library and are not user configurable. They may be used only with GPFS file systems and may improve file access for some applications; the user of a GPFS system is encouraged to experiment by running an application with and without this parameter set.
H5Dread
and H5Dwrite
will access the disk directly, and
H5Pset_cache
and H5Pset_chunk_cache
will have no effect on performance.
Raw dataset chunk caching is supported when this driver is used in read-only mode.
hid_t fapl_id |
IN: File access property list identifier. |
MPI_Comm comm |
IN: MPI-2 communicator. |
hbool_t use_gpfs_hints |
IN: Use of GPFS hints. |
SUBROUTINE h5pset_fapl_mpiposix_f(prp_id, comm, use_gpfs, hdferr) IMPLICIT NONE INTEGER(HID_T), INTENT(IN) :: prp_id ! Property list identifier INTEGER, INTENT(IN) :: comm ! MPI communicator to be used ! for file open as defined in ! MPI_FILE_OPEN of MPI-2 LOGICAL, INTENT(IN) :: use_gpfs INTEGER, INTENT(OUT) :: hdferr ! Error code END SUBROUTINE h5pset_fapl_mpiposix_f
Release | Change |
1.6.1 | Fortran subroutine introduced in this release. |
1.6.0 |
use_gpfs_hints parameter added. |
1.6.0 | C function introduced in this release. |