Opt out of cache expiry for `get_users_who_share_room_with_user` (#10826)

* Allow LruCaches to opt out of time-based expiry
* Don't expire `get_users_who_share_room` & friends

1 files changed, 8 insertions, 3 deletions

diff --git a/synapse/storage/databases/main/roommember.py b/synapse/storage/databases/main/roommember.py
index 9beeb96aa9..a4ec6bc328 100644
--- a/synapse/storage/databases/main/roommember.py
+++ b/synapse/storage/databases/main/roommember.py
@@ -162,7 +162,7 @@ class RoomMemberWorkerStore(EventsWorkerStore):
                 self._check_safe_current_state_events_membership_updated_txn,
             )
 
-    @cached(max_entries=100000, iterable=True)
+    @cached(max_entries=100000, iterable=True, prune_unread_entries=False)
     async def get_users_in_room(self, room_id: str) -> List[str]:
         return await self.db_pool.runInteraction(
             "get_users_in_room", self.get_users_in_room_txn, room_id
@@ -439,7 +439,7 @@ class RoomMemberWorkerStore(EventsWorkerStore):
 
         return results_dict.get("membership"), results_dict.get("event_id")
 
-    @cached(max_entries=500000, iterable=True)
+    @cached(max_entries=500000, iterable=True, prune_unread_entries=False)
     async def get_rooms_for_user_with_stream_ordering(
         self, user_id: str
     ) -> FrozenSet[GetRoomsForUserWithStreamOrdering]:
@@ -544,7 +544,12 @@ class RoomMemberWorkerStore(EventsWorkerStore):
         )
         return frozenset(r.room_id for r in rooms)
 
-    @cached(max_entries=500000, cache_context=True, iterable=True)
+    @cached(
+        max_entries=500000,
+        cache_context=True,
+        iterable=True,
+        prune_unread_entries=False,
+    )
     async def get_users_who_share_room_with_user(
         self, user_id: str, cache_context: _CacheContext
     ) -> Set[str]: