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| author | Richard Warren <Richard.Warren@hdfgroup.org> | 2017-09-28 20:27:29 (GMT) |
|---|---|---|
| committer | Richard Warren <Richard.Warren@hdfgroup.org> | 2017-09-28 20:27:29 (GMT) |
| commit | 81094ac3cfbf5785c0006516133d0dc34665b81c (patch) | |
| tree | f13cd6e113cc4edf125bf47fe664bff8e194ce1a /src/H5Fsuper.c | |
| parent | b5446a9c638b5a95b8dfe132f646aa4358d2b539 (diff) | |
| download | hdf5-81094ac3cfbf5785c0006516133d0dc34665b81c.zip hdf5-81094ac3cfbf5785c0006516133d0dc34665b81c.tar.gz hdf5-81094ac3cfbf5785c0006516133d0dc34665b81c.tar.bz2 | |
The initial coding for the superblock read optization
Diffstat (limited to 'src/H5Fsuper.c')
| -rw-r--r-- | src/H5Fsuper.c | 30 |
1 files changed, 28 insertions, 2 deletions
diff --git a/src/H5Fsuper.c b/src/H5Fsuper.c index 7c70a64..32051f3 100644 --- a/src/H5Fsuper.c +++ b/src/H5Fsuper.c @@ -333,6 +333,7 @@ H5F__super_read(H5F_t *f, hid_t meta_dxpl_id, hid_t raw_dxpl_id, hbool_t initial unsigned rw_flags; /* Read/write permissions for file */ hbool_t skip_eof_check = FALSE; /* Whether to skip checking the EOF value */ herr_t ret_value = SUCCEED; /* Return value */ + int mpi_rank = 0, mpi_size = 1; FUNC_ENTER_PACKAGE_TAG(meta_dxpl_id, H5AC__SUPERBLOCK_TAG, FAIL) @@ -354,8 +355,33 @@ H5F__super_read(H5F_t *f, hid_t meta_dxpl_id, hid_t raw_dxpl_id, hbool_t initial HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "can't get property list") /* Find the superblock */ - if(H5FD_locate_signature(&fdio_info, &super_addr) < 0) - HGOTO_ERROR(H5E_FILE, H5E_NOTHDF5, FAIL, "unable to locate file signature") +#ifdef H5_HAVE_PARALLEL + H5FD_GET_MPI_RANK_AND_SIZE(mpi_rank, mpi_size, f); + /* If we are an MPI application with at least two processes, the + * following superblock signature location optimization is applicable. + */ + if ( mpi_size > 1 ) { + MPI_Comm this_comm = MPI_COMM_NULL; + + if ( mpi_rank == 0 ) { + if(H5FD_locate_signature(&fdio_info, &super_addr) < 0) + HGOTO_ERROR(H5E_FILE, H5E_NOTHDF5, FAIL, "unable to locate file signature") + } + H5FD_GET_MPI_COMM(this_comm, f); + if (( this_comm == MPI_COMM_NULL ) || + ( MPI_Bcast(&super_addr,sizeof(super_addr), MPI_BYTE, 0, this_comm) != MPI_SUCCESS)) + HGOTO_ERROR(H5E_FILE, H5E_NOTHDF5, FAIL, "unable to locate file signature") + } + else { + /* Locate the signature as per per the serial library */ +#endif /* H5_HAVE_PARALLEL */ + + if(H5FD_locate_signature(&fdio_info, &super_addr) < 0) + HGOTO_ERROR(H5E_FILE, H5E_NOTHDF5, FAIL, "unable to locate file signature") + +#ifdef H5_HAVE_PARALLEL + } +#endif if(HADDR_UNDEF == super_addr) HGOTO_ERROR(H5E_FILE, H5E_NOTHDF5, FAIL, "file signature not found") |