From 3b3fed7229c8110870aefd4de740724fc607a46c Mon Sep 17 00:00:00 2001 From: Erik Johnston Date: Wed, 23 Aug 2023 09:23:22 +0100 Subject: [PATCH] Increase perf of read/write locks (#16149) We do this by marking the tables as `UNLOGGED` in PostgreSQL. --- changelog.d/16149.misc | 1 + .../02_read_write_locks_unlogged.sql.postgres | 30 +++++++++++++++++++ 2 files changed, 31 insertions(+) create mode 100644 changelog.d/16149.misc create mode 100644 synapse/storage/schema/main/delta/80/02_read_write_locks_unlogged.sql.postgres diff --git a/changelog.d/16149.misc b/changelog.d/16149.misc new file mode 100644 index 0000000000..8b6674d2aa --- /dev/null +++ b/changelog.d/16149.misc @@ -0,0 +1 @@ +Increase performance of read/write locks. diff --git a/synapse/storage/schema/main/delta/80/02_read_write_locks_unlogged.sql.postgres b/synapse/storage/schema/main/delta/80/02_read_write_locks_unlogged.sql.postgres new file mode 100644 index 0000000000..5b5dbf2687 --- /dev/null +++ b/synapse/storage/schema/main/delta/80/02_read_write_locks_unlogged.sql.postgres @@ -0,0 +1,30 @@ +/* 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. + */ + +-- Mark the worker_read_write_locks* tables as UNLOGGED, to increase +-- performance. This means that we don't replicate the tables, and they get +-- truncated on a crash. This is acceptable as a) in those cases it's likely +-- that Synapse needs to be stopped/restarted anyway, and b) the locks are +-- considered best-effort anyway. + +-- We need to remove and recreate the circular foreign key references, as +-- UNLOGGED tables can't reference normal tables. +ALTER TABLE worker_read_write_locks_mode DROP CONSTRAINT IF EXISTS worker_read_write_locks_mode_foreign; + +ALTER TABLE worker_read_write_locks SET UNLOGGED; +ALTER TABLE worker_read_write_locks_mode SET UNLOGGED; + +ALTER TABLE worker_read_write_locks_mode ADD CONSTRAINT worker_read_write_locks_mode_foreign + FOREIGN KEY (lock_name, lock_key, token) REFERENCES worker_read_write_locks(lock_name, lock_key, token) DEFERRABLE INITIALLY DEFERRED;