diff options
Diffstat (limited to 'src/H5Ocache.c')
| -rw-r--r-- | src/H5Ocache.c | 74 |
1 files changed, 74 insertions, 0 deletions
diff --git a/src/H5Ocache.c b/src/H5Ocache.c index 9e909a6..e64262b 100644 --- a/src/H5Ocache.c +++ b/src/H5Ocache.c @@ -560,6 +560,21 @@ done: * koziol@ncsa.uiuc.edu * Mar 20 2003 * + * Changes: In the parallel case, there is the possibility that the + * the object header may be flushed by different processes + * over the life of the computation. Thus we must ensure + * that the chunk images are up to date before we mark the + * messages clean -- as otherwise we may overwrite valid + * data with a blank section of a chunk image. + * + * To deal with this, I have added code to call + * H5O_chunk_serialize() for all chunks before we + * mark all messages as clean if we are not destroying the + * object. Do this in the parallel case only, as the problem + * can only occur in this context. + * + * JRM -- 10/12/10 + * *------------------------------------------------------------------------- */ static herr_t @@ -573,6 +588,30 @@ H5O_clear(H5F_t *f, H5O_t *oh, hbool_t destroy) /* check args */ HDassert(oh); +#ifdef H5_HAVE_PARALLEL + if ( ( oh->cache_info.is_dirty ) && ( ! destroy ) ) { + + size_t i; + + /* scan through all chunks associated with the object header, + * and cause them to update their images for all entries currently + * marked dirty. Must do this in the parallel case, as it is possible + * that this processor may clear this object header several times + * before flushing it -- thus causing undefined sections of the image + * to be written to disk overwriting valid data. + */ + + for ( i = 0; i < oh->nchunks; i++ ) { + + if ( H5O_chunk_serialize(f, oh, i) < 0 ) { + + HGOTO_ERROR(H5E_OHDR, H5E_CANTSERIALIZE, FAIL, + "unable to serialize object header chunk") + } + } + } +#endif /* H5_HAVE_PARALLEL */ + /* Mark messages as clean */ for(u = 0; u < oh->nmesgs; u++) oh->mesg[u].dirty = FALSE; @@ -830,6 +869,30 @@ done: * koziol@hdfgroup.org * July 12, 2008 * + * Changes: In the parallel case, there is the possibility that the + * the object header chunk may be flushed by different + * processes over the life of the computation. Thus we must + * ensure that the chunk image is up to date before we mark its + * messages clean -- as otherwise we may overwrite valid + * data with a blank section of a chunk image. + * + * To deal with this, I have added code to call + * H5O_chunk_serialize() for this chunk before we + * mark all messages as clean if we are not destroying the + * chunk. + * + * Do this in the parallel case only, as the problem + * can only occur in this context. + * + * Note that at present at least, it seems that this fix + * is not necessary, as we don't seem to be able to + * generate a dirty chunk without creating a dirty object + * header. However, the object header code will be changing + * a lot in the near future, so I'll leave this fix in + * for now, unless Quincey requests otherwise. + * + * JRM -- 10/12/10 + * *------------------------------------------------------------------------- */ static herr_t @@ -843,6 +906,17 @@ H5O_cache_chk_clear(H5F_t *f, H5O_chunk_proxy_t *chk_proxy, hbool_t destroy) /* check args */ HDassert(chk_proxy); +#ifdef H5_HAVE_PARALLEL + if ( ( chk_proxy->oh->cache_info.is_dirty ) && ( ! destroy ) ) { + + if ( H5O_chunk_serialize(f, chk_proxy->oh, chk_proxy->chunkno) < 0 ) { + + HGOTO_ERROR(H5E_OHDR, H5E_CANTSERIALIZE, FAIL, + "unable to serialize object header chunk") + } + } +#endif /* H5_HAVE_PARALLEL */ + /* Mark messages in chunk as clean */ for(u = 0; u < chk_proxy->oh->nmesgs; u++) if(chk_proxy->oh->mesg[u].chunkno == chk_proxy->chunkno) |