synapse/tests/util/test_lrucache.py
Erik Johnston 7b4d7429f8
Don't invalidate the entire event cache when we purge history (#16905)
We do this by adding support to the LRU cache for "extra indices" based
on the cached value. This allows us to efficiently map from room ID to
the cached events and only invalidate those.
2024-02-13 13:24:11 +00:00

416 lines
13 KiB
Python

#
# This file is licensed under the Affero General Public License (AGPL) version 3.
#
# Copyright 2015, 2016 OpenMarket Ltd
# 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 typing import List, Tuple
from unittest.mock import Mock, patch
from synapse.metrics.jemalloc import JemallocStats
from synapse.types import JsonDict
from synapse.util.caches.lrucache import LruCache, setup_expire_lru_cache_entries
from synapse.util.caches.treecache import TreeCache
from tests import unittest
from tests.unittest import override_config
class LruCacheTestCase(unittest.HomeserverTestCase):
def test_get_set(self) -> None:
cache: LruCache[str, str] = LruCache(1)
cache["key"] = "value"
self.assertEqual(cache.get("key"), "value")
self.assertEqual(cache["key"], "value")
def test_eviction(self) -> None:
cache: LruCache[int, int] = LruCache(2)
cache[1] = 1
cache[2] = 2
self.assertEqual(cache.get(1), 1)
self.assertEqual(cache.get(2), 2)
cache[3] = 3
self.assertEqual(cache.get(1), None)
self.assertEqual(cache.get(2), 2)
self.assertEqual(cache.get(3), 3)
def test_setdefault(self) -> None:
cache: LruCache[str, int] = LruCache(1)
self.assertEqual(cache.setdefault("key", 1), 1)
self.assertEqual(cache.get("key"), 1)
self.assertEqual(cache.setdefault("key", 2), 1)
self.assertEqual(cache.get("key"), 1)
cache["key"] = 2 # Make sure overriding works.
self.assertEqual(cache.get("key"), 2)
def test_pop(self) -> None:
cache: LruCache[str, int] = LruCache(1)
cache["key"] = 1
self.assertEqual(cache.pop("key"), 1)
self.assertEqual(cache.pop("key"), None)
def test_del_multi(self) -> None:
# The type here isn't quite correct as they don't handle TreeCache well.
cache: LruCache[Tuple[str, str], str] = LruCache(4, cache_type=TreeCache)
cache[("animal", "cat")] = "mew"
cache[("animal", "dog")] = "woof"
cache[("vehicles", "car")] = "vroom"
cache[("vehicles", "train")] = "chuff"
self.assertEqual(len(cache), 4)
self.assertEqual(cache.get(("animal", "cat")), "mew")
self.assertEqual(cache.get(("vehicles", "car")), "vroom")
cache.del_multi(("animal",)) # type: ignore[arg-type]
self.assertEqual(len(cache), 2)
self.assertEqual(cache.get(("animal", "cat")), None)
self.assertEqual(cache.get(("animal", "dog")), None)
self.assertEqual(cache.get(("vehicles", "car")), "vroom")
self.assertEqual(cache.get(("vehicles", "train")), "chuff")
# Man from del_multi say "Yes".
def test_clear(self) -> None:
cache: LruCache[str, int] = LruCache(1)
cache["key"] = 1
cache.clear()
self.assertEqual(len(cache), 0)
@override_config({"caches": {"per_cache_factors": {"mycache": 10}}})
def test_special_size(self) -> None:
cache: LruCache = LruCache(10, "mycache")
self.assertEqual(cache.max_size, 100)
class LruCacheCallbacksTestCase(unittest.HomeserverTestCase):
def test_get(self) -> None:
m = Mock()
cache: LruCache[str, str] = LruCache(1)
cache.set("key", "value")
self.assertFalse(m.called)
cache.get("key", callbacks=[m])
self.assertFalse(m.called)
cache.get("key", "value")
self.assertFalse(m.called)
cache.set("key", "value2")
self.assertEqual(m.call_count, 1)
cache.set("key", "value")
self.assertEqual(m.call_count, 1)
def test_multi_get(self) -> None:
m = Mock()
cache: LruCache[str, str] = LruCache(1)
cache.set("key", "value")
self.assertFalse(m.called)
cache.get("key", callbacks=[m])
self.assertFalse(m.called)
cache.get("key", callbacks=[m])
self.assertFalse(m.called)
cache.set("key", "value2")
self.assertEqual(m.call_count, 1)
cache.set("key", "value")
self.assertEqual(m.call_count, 1)
def test_set(self) -> None:
m = Mock()
cache: LruCache[str, str] = LruCache(1)
cache.set("key", "value", callbacks=[m])
self.assertFalse(m.called)
cache.set("key", "value")
self.assertFalse(m.called)
cache.set("key", "value2")
self.assertEqual(m.call_count, 1)
cache.set("key", "value")
self.assertEqual(m.call_count, 1)
def test_pop(self) -> None:
m = Mock()
cache: LruCache[str, str] = LruCache(1)
cache.set("key", "value", callbacks=[m])
self.assertFalse(m.called)
cache.pop("key")
self.assertEqual(m.call_count, 1)
cache.set("key", "value")
self.assertEqual(m.call_count, 1)
cache.pop("key")
self.assertEqual(m.call_count, 1)
def test_del_multi(self) -> None:
m1 = Mock()
m2 = Mock()
m3 = Mock()
m4 = Mock()
# The type here isn't quite correct as they don't handle TreeCache well.
cache: LruCache[Tuple[str, str], str] = LruCache(4, cache_type=TreeCache)
cache.set(("a", "1"), "value", callbacks=[m1])
cache.set(("a", "2"), "value", callbacks=[m2])
cache.set(("b", "1"), "value", callbacks=[m3])
cache.set(("b", "2"), "value", callbacks=[m4])
self.assertEqual(m1.call_count, 0)
self.assertEqual(m2.call_count, 0)
self.assertEqual(m3.call_count, 0)
self.assertEqual(m4.call_count, 0)
cache.del_multi(("a",)) # type: ignore[arg-type]
self.assertEqual(m1.call_count, 1)
self.assertEqual(m2.call_count, 1)
self.assertEqual(m3.call_count, 0)
self.assertEqual(m4.call_count, 0)
def test_clear(self) -> None:
m1 = Mock()
m2 = Mock()
cache: LruCache[str, str] = LruCache(5)
cache.set("key1", "value", callbacks=[m1])
cache.set("key2", "value", callbacks=[m2])
self.assertEqual(m1.call_count, 0)
self.assertEqual(m2.call_count, 0)
cache.clear()
self.assertEqual(m1.call_count, 1)
self.assertEqual(m2.call_count, 1)
def test_eviction(self) -> None:
m1 = Mock(name="m1")
m2 = Mock(name="m2")
m3 = Mock(name="m3")
cache: LruCache[str, str] = LruCache(2)
cache.set("key1", "value", callbacks=[m1])
cache.set("key2", "value", callbacks=[m2])
self.assertEqual(m1.call_count, 0)
self.assertEqual(m2.call_count, 0)
self.assertEqual(m3.call_count, 0)
cache.set("key3", "value", callbacks=[m3])
self.assertEqual(m1.call_count, 1)
self.assertEqual(m2.call_count, 0)
self.assertEqual(m3.call_count, 0)
cache.set("key3", "value")
self.assertEqual(m1.call_count, 1)
self.assertEqual(m2.call_count, 0)
self.assertEqual(m3.call_count, 0)
cache.get("key2")
self.assertEqual(m1.call_count, 1)
self.assertEqual(m2.call_count, 0)
self.assertEqual(m3.call_count, 0)
cache.set("key1", "value", callbacks=[m1])
self.assertEqual(m1.call_count, 1)
self.assertEqual(m2.call_count, 0)
self.assertEqual(m3.call_count, 1)
class LruCacheSizedTestCase(unittest.HomeserverTestCase):
def test_evict(self) -> None:
cache: LruCache[str, List[int]] = LruCache(5, size_callback=len)
cache["key1"] = [0]
cache["key2"] = [1, 2]
cache["key3"] = [3]
cache["key4"] = [4]
self.assertEqual(cache["key1"], [0])
self.assertEqual(cache["key2"], [1, 2])
self.assertEqual(cache["key3"], [3])
self.assertEqual(cache["key4"], [4])
self.assertEqual(len(cache), 5)
cache["key5"] = [5, 6]
self.assertEqual(len(cache), 4)
self.assertEqual(cache.get("key1"), None)
self.assertEqual(cache.get("key2"), None)
self.assertEqual(cache["key3"], [3])
self.assertEqual(cache["key4"], [4])
self.assertEqual(cache["key5"], [5, 6])
def test_zero_size_drop_from_cache(self) -> None:
"""Test that `drop_from_cache` works correctly with 0-sized entries."""
cache: LruCache[str, List[int]] = LruCache(5, size_callback=lambda x: 0)
cache["key1"] = []
self.assertEqual(len(cache), 0)
assert isinstance(cache.cache, dict)
cache.cache["key1"].drop_from_cache()
self.assertIsNone(
cache.pop("key1"), "Cache entry should have been evicted but wasn't"
)
class TimeEvictionTestCase(unittest.HomeserverTestCase):
"""Test that time based eviction works correctly."""
def default_config(self) -> JsonDict:
config = super().default_config()
config.setdefault("caches", {})["expiry_time"] = "30m"
return config
def test_evict(self) -> None:
setup_expire_lru_cache_entries(self.hs)
cache: LruCache[str, int] = LruCache(5, clock=self.hs.get_clock())
# Check that we evict entries we haven't accessed for 30 minutes.
cache["key1"] = 1
cache["key2"] = 2
self.reactor.advance(20 * 60)
self.assertEqual(cache.get("key1"), 1)
self.reactor.advance(20 * 60)
# We have only touched `key1` in the last 30m, so we expect that to
# still be in the cache while `key2` should have been evicted.
self.assertEqual(cache.get("key1"), 1)
self.assertEqual(cache.get("key2"), None)
# Check that re-adding an expired key works correctly.
cache["key2"] = 3
self.assertEqual(cache.get("key2"), 3)
self.reactor.advance(20 * 60)
self.assertEqual(cache.get("key2"), 3)
self.reactor.advance(20 * 60)
self.assertEqual(cache.get("key1"), None)
self.assertEqual(cache.get("key2"), 3)
class MemoryEvictionTestCase(unittest.HomeserverTestCase):
@override_config(
{
"caches": {
"cache_autotuning": {
"max_cache_memory_usage": "700M",
"target_cache_memory_usage": "500M",
"min_cache_ttl": "5m",
}
}
}
)
@patch("synapse.util.caches.lrucache.get_jemalloc_stats")
def test_evict_memory(self, jemalloc_interface: Mock) -> None:
mock_jemalloc_class = Mock(spec=JemallocStats)
jemalloc_interface.return_value = mock_jemalloc_class
# set the return value of get_stat() to be greater than max_cache_memory_usage
mock_jemalloc_class.get_stat.return_value = 924288000
setup_expire_lru_cache_entries(self.hs)
cache: LruCache[str, int] = LruCache(4, clock=self.hs.get_clock())
cache["key1"] = 1
cache["key2"] = 2
# advance the reactor less than the min_cache_ttl
self.reactor.advance(60 * 2)
# our items should still be in the cache
self.assertEqual(cache.get("key1"), 1)
self.assertEqual(cache.get("key2"), 2)
# advance the reactor past the min_cache_ttl
self.reactor.advance(60 * 6)
# the items should be cleared from cache
self.assertEqual(cache.get("key1"), None)
self.assertEqual(cache.get("key2"), None)
# add more stuff to caches
cache["key1"] = 1
cache["key2"] = 2
# set the return value of get_stat() to be lower than target_cache_memory_usage
mock_jemalloc_class.get_stat.return_value = 10000
# advance the reactor past the min_cache_ttl
self.reactor.advance(60 * 6)
# the items should still be in the cache
self.assertEqual(cache.get("key1"), 1)
self.assertEqual(cache.get("key2"), 2)
class ExtraIndexLruCacheTestCase(unittest.HomeserverTestCase):
def test_invalidate_simple(self) -> None:
cache: LruCache[str, int] = LruCache(10, extra_index_cb=lambda k, v: str(v))
cache["key1"] = 1
cache["key2"] = 2
cache.invalidate_on_extra_index("key1")
self.assertEqual(cache.get("key1"), 1)
self.assertEqual(cache.get("key2"), 2)
cache.invalidate_on_extra_index("1")
self.assertEqual(cache.get("key1"), None)
self.assertEqual(cache.get("key2"), 2)
def test_invalidate_multi(self) -> None:
cache: LruCache[str, int] = LruCache(10, extra_index_cb=lambda k, v: str(v))
cache["key1"] = 1
cache["key2"] = 1
cache["key3"] = 2
cache.invalidate_on_extra_index("key1")
self.assertEqual(cache.get("key1"), 1)
self.assertEqual(cache.get("key2"), 1)
self.assertEqual(cache.get("key3"), 2)
cache.invalidate_on_extra_index("1")
self.assertEqual(cache.get("key1"), None)
self.assertEqual(cache.get("key2"), None)
self.assertEqual(cache.get("key3"), 2)