mirror of
https://git.anonymousland.org/anonymousland/synapse.git
synced 2024-12-20 20:54:19 -05:00
38 lines
1.6 KiB
SQL
38 lines
1.6 KiB
SQL
/* Copyright 2021 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.
|
|
*/
|
|
|
|
|
|
-- A noddy implementation of a distributed lock across workers. While a worker
|
|
-- has taken a lock out they should regularly update the `last_renewed_ts`
|
|
-- column, a lock will be considered dropped if `last_renewed_ts` is from ages
|
|
-- ago.
|
|
CREATE TABLE worker_locks (
|
|
lock_name TEXT NOT NULL,
|
|
lock_key TEXT NOT NULL,
|
|
-- We write the instance name to ease manual debugging, we don't ever read
|
|
-- from it.
|
|
-- Note: instance names aren't guarenteed to be unique.
|
|
instance_name TEXT NOT NULL,
|
|
-- A random string generated each time an instance takes out a lock. Used by
|
|
-- the instance to tell whether the lock is still held by it (e.g. in the
|
|
-- case where the process stalls for a long time the lock may time out and
|
|
-- be taken out by another instance, at which point the original instance
|
|
-- can tell it no longer holds the lock as the tokens no longer match).
|
|
token TEXT NOT NULL,
|
|
last_renewed_ts BIGINT NOT NULL
|
|
);
|
|
|
|
CREATE UNIQUE INDEX worker_locks_key ON worker_locks (lock_name, lock_key);
|