> Author: stefan2 > Date: Sat Oct 13 05:49:50 2012 > New Revision: 1397773 > > URL: http://svn.apache.org/viewvc?rev=1397773&view=rev > Log: > Due to public request: apply rep-sharing to equal data reps within > the same transaction. > > The idea is simple. When writing a noderev to the txn folder, > write another file named by the rep's SHA1 and store the rep > struct in there. Lookup is then straight-forward.
Hi Stefan. What's the scalability? I'm wondering about the big-O performance of storing 10000 or 100000 files in the dir. - Julian > * subversion/libsvn_fs_fs/fs_fs.c > (svn_fs_fs__put_node_revision): also look for SHA1-named files > (get_shared_rep): write SHA1-named files > > Modified: > subversion/trunk/subversion/libsvn_fs_fs/fs_fs.c > > Modified: subversion/trunk/subversion/libsvn_fs_fs/fs_fs.c > URL: > http://svn.apache.org/viewvc/subversion/trunk/subversion/libsvn_fs_fs/fs_fs.c?rev=1397773&r1=1397772&r2=1397773&view=diff > ============================================================================== > --- subversion/trunk/subversion/libsvn_fs_fs/fs_fs.c (original) > +++ subversion/trunk/subversion/libsvn_fs_fs/fs_fs.c Sat Oct 13 05:49:50 2012 > @@ -2585,6 +2585,10 @@ svn_fs_fs__put_node_revision(svn_fs_t *f > fs_fs_data_t *ffd = fs->fsap_data; > apr_file_t *noderev_file; > const char *txn_id = svn_fs_fs__id_txn_id(id); > + const char *sha1 = ffd->rep_sharing_allowed && > noderev->data_rep > + ? > svn_checksum_to_cstring(noderev->data_rep->sha1_checksum, > + pool) > + : NULL; > > noderev->is_fresh_txn_root = fresh_txn_root; > > @@ -2603,7 +2607,32 @@ svn_fs_fs__put_node_revision(svn_fs_t *f > svn_fs_fs__fs_supports_mergeinfo(fs), > pool)); > > - return svn_io_file_close(noderev_file, pool); > + SVN_ERR(svn_io_file_close(noderev_file, pool)); > + > + /* if rep sharing has been enabled and the noderev has a data rep and > + * its SHA-1 is known, store the rep struct under its SHA1. */ > + if (sha1) > + { > + apr_file_t *rep_file; > + const char *file_name = svn_dirent_join(path_txn_dir(fs, txn_id, pool), > + sha1, pool); > + const char *rep_string = representation_string(noderev->data_rep, > + ffd->format, > + (noderev->kind > + == svn_node_dir), > + FALSE, > + pool); > + SVN_ERR(svn_io_file_open(&rep_file, file_name, > + APR_WRITE | APR_CREATE | APR_TRUNCATE > + | APR_BUFFERED, APR_OS_DEFAULT, pool)); > + > + SVN_ERR(svn_io_file_write_full(rep_file, rep_string, > + strlen(rep_string), NULL, pool)); > + > + SVN_ERR(svn_io_file_close(rep_file, pool)); > + } > + > + return SVN_NO_ERROR; > } > > > @@ -7083,6 +7112,30 @@ get_shared_rep(representation_t **old_re > } > } > > + /* look for intra-revision matches (usually data reps but not limited > + to them in case props happen to look like some data rep) > + */ > + if (*old_rep == NULL && rep->txn_id) > + { > + svn_node_kind_t kind; > + const char *file_name > + = svn_dirent_join(path_txn_dir(fs, rep->txn_id, pool), > + svn_checksum_to_cstring(rep->sha1_checksum, pool), > + pool); > + > + /* in our txn, is there a rep file named with the wanted SHA1? > + If so, read it and use that rep. > + */ > + SVN_ERR(svn_io_check_path(file_name, &kind, pool)); > + if (kind == svn_node_file) > + { > + svn_stringbuf_t *rep_string; > + SVN_ERR(svn_stringbuf_from_file2(&rep_string, file_name, pool)); > + SVN_ERR(read_rep_offsets_body(old_rep, rep_string->data, > + rep->txn_id, FALSE, pool)); > + } > + } > + > /* Add information that is missing in the cached data. */ > if (*old_rep) > { >
