From d0de452d1222ada8d219a8c5bc42498a89e5ecea Mon Sep 17 00:00:00 2001 From: Sean Quah <8349537+squahtx@users.noreply.github.com> Date: Fri, 19 May 2023 11:17:12 +0100 Subject: Fix `HomeServer`s leaking during `trial` test runs (#15630) This change fixes two memory leaks during `trial` test runs. Garbage collection is disabled during each test case and a gen-0 GC is run at the end of each test. However, when the gen-0 GC is run, the `TestCase` object usually still holds references to the `HomeServer` used during the test. As a result, the `HomeServer` gets promoted to gen-1 and then never garbage collected. Fix this by periodically running full GCs. Additionally, fix `HomeServer`s leaking after tests that touch inbound federation due to `FederationRateLimiter`s adding themselves to a global set, by turning the set into a `WeakSet`. Resolves #15622. Signed-off-by: Sean Quah --- synapse/util/ratelimitutils.py | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'synapse') diff --git a/synapse/util/ratelimitutils.py b/synapse/util/ratelimitutils.py index f262bf95a0..2ad55ac13e 100644 --- a/synapse/util/ratelimitutils.py +++ b/synapse/util/ratelimitutils.py @@ -25,10 +25,12 @@ from typing import ( Iterator, List, Mapping, + MutableSet, Optional, Set, Tuple, ) +from weakref import WeakSet from prometheus_client.core import Counter from typing_extensions import ContextManager @@ -86,7 +88,9 @@ queue_wait_timer = Histogram( ) -_rate_limiter_instances: Set["FederationRateLimiter"] = set() +# This must be a `WeakSet`, otherwise we indirectly hold on to entire `HomeServer`s +# during trial test runs and leak a lot of memory. +_rate_limiter_instances: MutableSet["FederationRateLimiter"] = WeakSet() # Protects the _rate_limiter_instances set from concurrent access _rate_limiter_instances_lock = threading.Lock() -- cgit 1.4.1