1 files changed, 2 insertions, 1 deletions
diff --git a/synapse/util/ratelimitutils.py b/synapse/util/ratelimitutils.py
index ea321bc6a9..4076eed269 100644
--- a/synapse/util/ratelimitutils.py
+++ b/synapse/util/ratelimitutils.py
@@ -18,6 +18,7 @@ from twisted.internet import defer
 from synapse.api.errors import LimitExceededError
 
 from synapse.util.async import sleep
+from synapse.util.logcontext import preserve_fn
 
 import collections
 import contextlib
@@ -163,7 +164,7 @@ class _PerHostRatelimiter(object):
                 "Ratelimit [%s]: sleeping req",
                 id(request_id),
             )
-            ret_defer = sleep(self.sleep_msec / 1000.0)
+            ret_defer = preserve_fn(sleep)(self.sleep_msec / 1000.0)
 
             self.sleeping_requests.add(request_id)