mirror of
https://github.com/element-hq/synapse.git
synced 2024-12-23 05:00:24 +03:00
cb562d73aa
When a lot of locks are waiting for a single lock, notifying all locks independently with `call_later` on each release is really costly and incurs some kind of async contention, where the CPU is spinning a lot for not much. The included test is taking around 30s before the change, and 0.5s after. It was found following failing tests with https://github.com/element-hq/synapse/pull/16827.
104 lines
3.4 KiB
Python
104 lines
3.4 KiB
Python
#
|
|
# This file is licensed under the Affero General Public License (AGPL) version 3.
|
|
#
|
|
# Copyright 2023 The Matrix.org Foundation C.I.C.
|
|
# Copyright (C) 2023 New Vector, Ltd
|
|
#
|
|
# This program is free software: you can redistribute it and/or modify
|
|
# it under the terms of the GNU Affero General Public License as
|
|
# published by the Free Software Foundation, either version 3 of the
|
|
# License, or (at your option) any later version.
|
|
#
|
|
# See the GNU Affero General Public License for more details:
|
|
# <https://www.gnu.org/licenses/agpl-3.0.html>.
|
|
#
|
|
# Originally licensed under the Apache License, Version 2.0:
|
|
# <http://www.apache.org/licenses/LICENSE-2.0>.
|
|
#
|
|
# [This file includes modifications made by New Vector Limited]
|
|
#
|
|
#
|
|
|
|
from twisted.internet import defer
|
|
from twisted.test.proto_helpers import MemoryReactor
|
|
|
|
from synapse.server import HomeServer
|
|
from synapse.util import Clock
|
|
|
|
from tests import unittest
|
|
from tests.replication._base import BaseMultiWorkerStreamTestCase
|
|
from tests.utils import test_timeout
|
|
|
|
|
|
class WorkerLockTestCase(unittest.HomeserverTestCase):
|
|
def prepare(
|
|
self, reactor: MemoryReactor, clock: Clock, homeserver: HomeServer
|
|
) -> None:
|
|
self.worker_lock_handler = self.hs.get_worker_locks_handler()
|
|
|
|
def test_wait_for_lock_locally(self) -> None:
|
|
"""Test waiting for a lock on a single worker"""
|
|
|
|
lock1 = self.worker_lock_handler.acquire_lock("name", "key")
|
|
self.get_success(lock1.__aenter__())
|
|
|
|
lock2 = self.worker_lock_handler.acquire_lock("name", "key")
|
|
d2 = defer.ensureDeferred(lock2.__aenter__())
|
|
self.assertNoResult(d2)
|
|
|
|
self.get_success(lock1.__aexit__(None, None, None))
|
|
|
|
self.get_success(d2)
|
|
self.get_success(lock2.__aexit__(None, None, None))
|
|
|
|
def test_lock_contention(self) -> None:
|
|
"""Test lock contention when a lot of locks wait on a single worker"""
|
|
|
|
# It takes around 0.5s on a 5+ years old laptop
|
|
with test_timeout(5):
|
|
nb_locks = 500
|
|
d = self._take_locks(nb_locks)
|
|
self.assertEqual(self.get_success(d), nb_locks)
|
|
|
|
async def _take_locks(self, nb_locks: int) -> int:
|
|
locks = [
|
|
self.hs.get_worker_locks_handler().acquire_lock("test_lock", "")
|
|
for _ in range(nb_locks)
|
|
]
|
|
|
|
nb_locks_taken = 0
|
|
for lock in locks:
|
|
async with lock:
|
|
nb_locks_taken += 1
|
|
|
|
return nb_locks_taken
|
|
|
|
|
|
class WorkerLockWorkersTestCase(BaseMultiWorkerStreamTestCase):
|
|
def prepare(
|
|
self, reactor: MemoryReactor, clock: Clock, homeserver: HomeServer
|
|
) -> None:
|
|
self.main_worker_lock_handler = self.hs.get_worker_locks_handler()
|
|
|
|
def test_wait_for_lock_worker(self) -> None:
|
|
"""Test waiting for a lock on another worker"""
|
|
|
|
worker = self.make_worker_hs(
|
|
"synapse.app.generic_worker",
|
|
extra_config={
|
|
"redis": {"enabled": True},
|
|
},
|
|
)
|
|
worker_lock_handler = worker.get_worker_locks_handler()
|
|
|
|
lock1 = self.main_worker_lock_handler.acquire_lock("name", "key")
|
|
self.get_success(lock1.__aenter__())
|
|
|
|
lock2 = worker_lock_handler.acquire_lock("name", "key")
|
|
d2 = defer.ensureDeferred(lock2.__aenter__())
|
|
self.assertNoResult(d2)
|
|
|
|
self.get_success(lock1.__aexit__(None, None, None))
|
|
|
|
self.get_success(d2)
|
|
self.get_success(lock2.__aexit__(None, None, None))
|