diff options
Diffstat (limited to 'src/H5Dchunk.c')
| -rw-r--r-- | src/H5Dchunk.c | 37 |
1 files changed, 35 insertions, 2 deletions
diff --git a/src/H5Dchunk.c b/src/H5Dchunk.c index e3f6410..e64a60f 100644 --- a/src/H5Dchunk.c +++ b/src/H5Dchunk.c @@ -2933,8 +2933,41 @@ H5D__chunk_lookup(const H5D_t *dset, const hsize_t *scaled, H5F_set_coll_md_read(idx_info.f, temp_cmr); #endif /* H5_HAVE_PARALLEL */ - /* Cache the information retrieved */ - H5D__chunk_cinfo_cache_update(&dset->shared->cache.chunk.last, udata); + /* + * Cache the information retrieved. + * + * Note that if we are writing to the dataset in parallel and filters + * are involved, we skip caching this information as it is highly likely + * that the chunk information will be invalidated as a result of the + * filter operation (e.g. the chunk gets re-allocated to a different + * address in the file and/or gets re-allocated with a different size). + * If we were to cache this information, subsequent reads/writes would + * retrieve the invalid information and cause a variety of issues. + * + * It has been verified that in the serial library, when writing to chunks + * with the real chunk cache disabled and with filters involved, the + * functions within this file are correctly called in such a manner that + * this single chunk cache is always updated correctly. Therefore, this + * check is not needed for the serial library. + * + * This is an ugly and potentially frail check, but the + * H5D__chunk_cinfo_cache_reset() function is not currently available + * to functions outside of this file, so outside functions can not + * invalidate this single chunk cache. Even if the function were available, + * this check prevents us from doing the work of going through and caching + * each chunk in the write operation, when we're only going to invalidate + * the cache at the end of a parallel write anyway. + * + * - JTH (7/13/2018) + */ +#ifdef H5_HAVE_PARALLEL + if ( !( (H5F_HAS_FEATURE(idx_info.f, H5FD_FEAT_HAS_MPI)) + && (H5F_INTENT(dset->oloc.file) & H5F_ACC_RDWR) + && dset->shared->dcpl_cache.pline.nused + ) + ) +#endif + H5D__chunk_cinfo_cache_update(&dset->shared->cache.chunk.last, udata); } /* end if */ } /* end else */ |