From 24905b78f57c330c8e7bf53633326a311b945196 Mon Sep 17 00:00:00 2001
From: Eric Eastwood <erice@element.io>
Date: Wed, 21 Sep 2022 17:55:45 -0500
Subject: [PATCH] Move cache invalidation to the main thread

See https://github.com/matrix-org/synapse/pull/13861#discussion_r976982283
---
 synapse/storage/controllers/persist_events.py | 32 ++++++++++++++++++-
 synapse/storage/databases/main/cache.py       |  3 --
 synapse/storage/databases/main/events.py      | 18 -----------
 3 files changed, 31 insertions(+), 22 deletions(-)

diff --git a/synapse/storage/controllers/persist_events.py b/synapse/storage/controllers/persist_events.py
index bde7a6648a..ffe14283a3 100644
--- a/synapse/storage/controllers/persist_events.py
+++ b/synapse/storage/controllers/persist_events.py
@@ -43,7 +43,7 @@ from prometheus_client import Counter, Histogram
 from twisted.internet import defer
 
 from synapse.api.constants import EventTypes, Membership
-from synapse.events import EventBase
+from synapse.events import EventBase, relation_from_event
 from synapse.events.snapshot import EventContext
 from synapse.logging.context import PreserveLoggingContext, make_deferred_yieldable
 from synapse.logging.tracing import (
@@ -435,6 +435,21 @@ class EventsPersistenceStorageController:
             else:
                 events.append(event)
 
+                # We expect events to be persisted by this point
+                assert event.internal_metadata.stream_ordering
+                # Invalidate related caches after we persist a new event
+                relation = relation_from_event(event)
+                self.main_store._invalidate_caches_for_event(
+                    stream_ordering=event.internal_metadata.stream_ordering,
+                    event_id=event.event_id,
+                    room_id=event.room_id,
+                    etype=event.type,
+                    state_key=event.state_key if hasattr(event, "state_key") else None,
+                    redacts=event.redacts,
+                    relates_to=relation.parent_id if relation else None,
+                    backfilled=backfilled,
+                )
+
         return (
             events,
             self.main_store.get_room_max_token(),
@@ -467,6 +482,21 @@ class EventsPersistenceStorageController:
         replaced_event = replaced_events.get(event.event_id)
         if replaced_event:
             event = await self.main_store.get_event(replaced_event)
+        else:
+            # We expect events to be persisted by this point
+            assert event.internal_metadata.stream_ordering
+            # Invalidate related caches after we persist a new event
+            relation = relation_from_event(event)
+            self.main_store._invalidate_caches_for_event(
+                stream_ordering=event.internal_metadata.stream_ordering,
+                event_id=event.event_id,
+                room_id=event.room_id,
+                etype=event.type,
+                state_key=event.state_key if hasattr(event, "state_key") else None,
+                redacts=event.redacts,
+                relates_to=relation.parent_id if relation else None,
+                backfilled=backfilled,
+            )
 
         event_stream_id = event.internal_metadata.stream_ordering
         # stream ordering should have been assigned by now
diff --git a/synapse/storage/databases/main/cache.py b/synapse/storage/databases/main/cache.py
index 53646b978a..b28a91e8f6 100644
--- a/synapse/storage/databases/main/cache.py
+++ b/synapse/storage/databases/main/cache.py
@@ -228,9 +228,6 @@ class CacheInvalidationWorkerStore(SQLBaseStore):
             room_id,
             event_id,
         )
-        logger.info(
-            "CacheInvalidationWorkerStore self.have_seen_event=%s", self.have_seen_event
-        )
         self._invalidate_local_get_event_cache(event_id)
         self.have_seen_event.invalidate(((room_id, event_id),))
 
diff --git a/synapse/storage/databases/main/events.py b/synapse/storage/databases/main/events.py
index 368e9b47e9..5932668f2f 100644
--- a/synapse/storage/databases/main/events.py
+++ b/synapse/storage/databases/main/events.py
@@ -434,24 +434,6 @@ class PersistEventsStore:
 
         self._store_event_txn(txn, events_and_contexts=events_and_contexts)
 
-        for event, _ in events_and_contexts:
-            # We expect events to be persisted by this point
-            assert event.internal_metadata.stream_ordering
-
-            relation = relation_from_event(event)
-            self.store._invalidate_caches_for_event(
-                stream_ordering=event.internal_metadata.stream_ordering,
-                event_id=event.event_id,
-                room_id=event.room_id,
-                etype=event.type,
-                state_key=None,  # event.state_key,
-                # TODO
-                redacts=None,
-                relates_to=relation.parent_id if relation else None,
-                # TODO
-                backfilled=False,
-            )
-
         self._persist_transaction_ids_txn(txn, events_and_contexts)
 
         # Insert into event_to_state_groups.