Remove auth_event_id caching is it doesn't make a noticeable difference

1 files changed, 6 insertions, 28 deletions

diff --git a/synapse/handlers/room_batch.py b/synapse/handlers/room_batch.py
index 89dbbb0c89..9528c2ffe7 100644
--- a/synapse/handlers/room_batch.py
+++ b/synapse/handlers/room_batch.py
@@ -302,12 +302,6 @@ class RoomBatchHandler:
         # another event in the batch with the same type
         event_type_to_context_cache: Dict[str, EventContext] = {}
 
-        # Map from (event.sender, event.type) to auth_event_ids that we can re-use and create
-        # another event in the batch with the same sender and type
-        event_sender_and_type_to_auth_event_ids_cache: Dict[
-            Tuple(str, str), List[str]
-        ] = {}
-
         # Make the historical event chain float off on its own by specifying no
         # prev_events for the first event in the chain which causes the HS to
         # ask for the state at the start of the batch later.
@@ -356,11 +350,6 @@ class RoomBatchHandler:
                 # Cache the context so we can re-use it for events in
                 # the batch that have the same type.
                 event_type_to_context_cache[event.type] = context
-                # Cache the auth_event_ids so we can re-use it for events in
-                # the batch that have the same sender and type.
-                event_sender_and_type_to_auth_event_ids_cache[
-                    (event.sender, event.type)
-                ] = event.auth_event_ids()
 
                 # Normally this is done when persisting the event but we have to
                 # pre-emptively do it here because we create all the events first,
@@ -381,27 +370,16 @@ class RoomBatchHandler:
                 # TODO: Can we get away without this? Can't we just rely on validate_new below?
                 # self.validator.validate_builder(builder)
 
-                resultant_auth_event_ids = (
-                    event_sender_and_type_to_auth_event_ids_cache.get(
-                        (ev["sender"], ev["type"])
-                    )
+                stripped_auth_event_ids = await self.event_creation_handler.strip_auth_event_ids_for_given_event_builder(
+                    builder=builder,
+                    prev_event_ids=prev_event_ids,
+                    auth_event_ids=auth_event_ids,
+                    depth=inherited_depth,
                 )
-                if resultant_auth_event_ids is None:
-                    resultant_auth_event_ids = await self.event_creation_handler.strip_auth_event_ids_for_given_event_builder(
-                        builder=builder,
-                        prev_event_ids=prev_event_ids,
-                        auth_event_ids=auth_event_ids,
-                        depth=inherited_depth,
-                    )
-                    # Cache the auth_event_ids so we can re-use it for events in
-                    # the batch that have the same sender and type.
-                    event_sender_and_type_to_auth_event_ids_cache[
-                        (ev["sender"], ev["type"])
-                    ] = resultant_auth_event_ids
 
                 event = await builder.build(
                     prev_event_ids=event_dict.get("prev_events"),
-                    auth_event_ids=resultant_auth_event_ids.copy(),
+                    auth_event_ids=stripped_auth_event_ids,
                     depth=inherited_depth,
                 )
                 # We can re-use the context per-event type because it will