diff options
| author | Tim Beale <timbeale@catalyst.net.nz> | 2019-02-04 10:49:03 +1300 |
|---|---|---|
| committer | Stefan Metzmacher <metze@samba.org> | 2019-02-13 11:43:25 +0100 |
| commit | d3a9f298f49b9e9950315007667cb10a3e51ffde (patch) | |
| tree | 9fcb5d939bc19c8e03718af58025197ec5f7f62d /lib | |
| parent | 9917a7e70eae095647af00c1ea4436bacdcef386 (diff) | |
| download | samba-d3a9f298f49b9e9950315007667cb10a3e51ffde.tar.gz | |
ldb: Avoid inefficient one-level searches
Commit 88ae60ed186c9 introduced a problem that made one-level
searches inefficient if there were a lot of child objects in the same
level, and the requested object didn't exist. Basically, it ignored the
case where ldb_kv_index_dn() returned LDB_ERR_NO_SUCH_OBJECT, i.e. the
indexed lookup was successful, but didn't find a match. At which point,
there was no more processing we needed to do.
The behaviour after 88ae60ed186c9 was to fall-through and run the
ldb_kv_index_filter() function over *all* the children. This still
returned the correct result, but could be costly if there were a lot of
children.
The case 88ae60ed186c9 was trying to fix was where we could not do
an indexed search (e.g. trying to match on a 'attribute=*' filter). In
which case we want to ignore the LDB_ERR_OPERATIONS_ERROR and just run
ldb_kv_index_filter() over all the children. This is still more
efficient than the fallback of doing a full database scan.
This patch adds in a short-circuit for the NO_SUCH_OBJECT case, so we
can skip the unnecessary ldb_kv_index_filter() work.
BUG: https://bugzilla.samba.org/show_bug.cgi?id=13762
Signed-off-by: Tim Beale <timbeale@catalyst.net.nz>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>
(Manual merge of commit 9a893f9613bd6440ab in master)
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/ldb/ldb_tdb/ldb_index.c | 18 |
1 files changed, 14 insertions, 4 deletions
diff --git a/lib/ldb/ldb_tdb/ldb_index.c b/lib/ldb/ldb_tdb/ldb_index.c index 429c8f5aa24..f07c9a818c4 100644 --- a/lib/ldb/ldb_tdb/ldb_index.c +++ b/lib/ldb/ldb_tdb/ldb_index.c @@ -1835,13 +1835,23 @@ int ltdb_search_indexed(struct ltdb_context *ac, uint32_t *match_count) } /* * Here we load the index for the tree. - * - * We only care if this is successful, if the - * index can't trim the result list down then - * the ONELEVEL index is still good enough. */ ret = ltdb_index_dn(ac->module, ltdb, ac->tree, idx_one_tree_list); + + /* + * We can stop if we're sure the object doesn't exist + */ + if (ret == LDB_ERR_NO_SUCH_OBJECT) { + talloc_free(idx_one_tree_list); + talloc_free(dn_list); + return LDB_ERR_NO_SUCH_OBJECT; + } + + /* We only care if this is successful, if the + * index can't trim the result list down then + * the ONELEVEL index is still good enough. + */ if (ret == LDB_SUCCESS) { if (!list_intersect(ldb, ltdb, dn_list, |