Fix a performance issue introduced in Synapse v1.83.0 which meant that purging rooms was very slow and database-intensive. (#15693)

* Add indices required to efficiently validate new foreign key constraints on stream_ordering

* Newsfile

Signed-off-by: Olivier Wilkinson (reivilibre) <oliverw@matrix.org>

---------

Signed-off-by: Olivier Wilkinson (reivilibre) <oliverw@matrix.org>

1 files changed, 20 insertions, 0 deletions

diff --git a/synapse/storage/schema/main/delta/77/14bg_indices_event_stream_ordering.sql b/synapse/storage/schema/main/delta/77/14bg_indices_event_stream_ordering.sql
new file mode 100644

index 0000000000..ec8cd522ec
--- /dev/null
+++ b/synapse/storage/schema/main/delta/77/14bg_indices_event_stream_ordering.sql
@@ -0,0 +1,20 @@
+/* Copyright 2023 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+INSERT INTO background_updates (ordering, update_name, progress_json)
+    VALUES
+        (7714, 'current_state_events_stream_ordering_idx', '{}'),
+        (7714, 'local_current_membership_stream_ordering_idx', '{}'),
+        (7714, 'room_memberships_stream_ordering_idx', '{}');