H5P_SET_DXPL_MPIO_CHUNK_OPT
Sets a flag specifying linked-chunk I/O or multi-chunk I/O
Procedure:
H5P_SET_DXPL_MPIO_CHUNK_OPT ( dxpl_id, opt_mode )
Signature:
herr_t H5Pset_dxpl_mpio_chunk_opt
(hid_t dxpl_id,
H5FD_mpio_chunk_opt_t opt_mode)
Parameters:
hid_t dxpl_id | IN: Data transfer property list identifier |
H5FD_mpio_chunk_opt_t opt_mode | IN: Optimization flag specifying linked-chunk I/O or multi-chunk I/O |
Description:
H5P_SET_DXPL_MPIO_CHUNK_OPT specifies whether I/O is to be performed as linked-chunk I/O or as multi-chunk I/O. This function overrides the HDF5 library's internal algorithm for determining which mechanism to use.
When an application uses collective I/O with chunked storage, the HDF5 library normally uses an internal algorithm to determine whether that I/O activity should be conducted as one linked-chunk I/O or as multi-chunk I/O. H5P_SET_DXPL_MPIO_CHUNK_OPT
H5P_SET_DXPL_MPIO_CHUNK_OPTopt_mode:
H5FD_MPIO_CHUNK_ONE_IO | Do one link chunked I/O |
H5FD_MPIO_CHUNK_MULTI_IO | Do multi-chunked I/O |
This function works by setting a corresponding property in the dataset transfer property list dxpl_id.
The library performs I/O in the specified manner unless it determines that the low-level MPI IO package does not support the requested behavior; in such cases, the HDF5 library will internally use independent I/O.
Use of this function is optional.
Returns:
Returns a non-negative value if successful. Otherwise returns a negative value.
Example:
History:
--- Last Modified: January 03, 2018 | 02:55 PM
