diff --git a/synapse/storage/events.py b/synapse/storage/events.py
index 87d0b78a2d..6d2aae9c4a 100644
--- a/synapse/storage/events.py
+++ b/synapse/storage/events.py
@@ -344,7 +344,9 @@ class EventsStore(EventsWorkerStore):
new_forward_extremeties = {}
# map room_id->(type,state_key)->event_id tracking the full
- # state in each room after adding these events
+ # state in each room after adding these events.
+ # This is simply used to prefill the get_current_state_ids
+ # cache
current_state_for_room = {}
# map room_id->(to_delete, to_insert) where to_delete is a list
@@ -419,28 +421,40 @@ class EventsStore(EventsWorkerStore):
logger.info(
"Calculating state delta for room %s", room_id,
)
-
with Measure(
- self._clock,
- "persist_events.get_new_state_after_events",
+ self._clock,
+ "persist_events.get_new_state_after_events",
):
- current_state = yield self._get_new_state_after_events(
+ res = yield self._get_new_state_after_events(
room_id,
ev_ctx_rm,
latest_event_ids,
new_latest_event_ids,
)
-
- if current_state is not None:
- current_state_for_room[room_id] = current_state
+ current_state, delta_ids = res
+
+ # If either are not None then there has been a change,
+ # and we need to work out the delta (or use that
+ # given)
+ if delta_ids is not None:
+ # If there is a delta we know that we've
+ # only added or replaced state, never
+ # removed keys entirely.
+ state_delta_for_room[room_id] = ([], delta_ids)
+ elif current_state is not None:
with Measure(
- self._clock,
- "persist_events.calculate_state_delta",
+ self._clock,
+ "persist_events.calculate_state_delta",
):
delta = yield self._calculate_state_delta(
room_id, current_state,
)
- state_delta_for_room[room_id] = delta
+ state_delta_for_room[room_id] = delta
+
+ # If we have the current_state then lets prefill
+ # the cache with it.
+ if current_state is not None:
+ current_state_for_room[room_id] = current_state
yield self.runInteraction(
"persist_events",
@@ -539,9 +553,10 @@ class EventsStore(EventsWorkerStore):
the new forward extremities for the room.
Returns:
- Deferred[dict[(str,str), str]|None]:
- None if there are no changes to the room state, or
- a dict of (type, state_key) -> event_id].
+ Deferred[tuple[dict[(str,str), str]|None, dict[(str,str), str]|None]]:
+ Returns a tuple of two state maps, the first being the full new current
+ state and the second being the delta to the existing current state.
+ If both are None then there has been no change.
"""
if not new_latest_event_ids:
@@ -549,6 +564,9 @@ class EventsStore(EventsWorkerStore):
# map from state_group to ((type, key) -> event_id) state map
state_groups_map = {}
+
+ state_group_deltas = {}
+
for ev, ctx in events_context:
if ctx.state_group is None:
# I don't think this can happen, but let's double-check
@@ -567,6 +585,9 @@ class EventsStore(EventsWorkerStore):
if current_state_ids is not None:
state_groups_map[ctx.state_group] = current_state_ids
+ if ctx.prev_group:
+ state_group_deltas[(ctx.prev_group, ctx.state_group)] = ctx.delta_ids
+
# We need to map the event_ids to their state groups. First, let's
# check if the event is one we're persisting, in which case we can
# pull the state group from its context.
@@ -608,7 +629,7 @@ class EventsStore(EventsWorkerStore):
# If they old and new groups are the same then we don't need to do
# anything.
if old_state_groups == new_state_groups:
- return
+ defer.returnValue((None, None))
# Now that we have calculated new_state_groups we need to get
# their state IDs so we can resolve to a single state set.
@@ -620,7 +641,17 @@ class EventsStore(EventsWorkerStore):
if len(new_state_groups) == 1:
# If there is only one state group, then we know what the current
# state is.
- defer.returnValue(state_groups_map[new_state_groups.pop()])
+ new_state_group = new_state_groups.pop()
+
+ delta_ids = None
+ if len(old_state_groups) == 1:
+ old_state_group = old_state_groups.pop()
+
+ delta_ids = state_group_deltas.get(
+ (old_state_group, new_state_group,), None
+ )
+
+ defer.returnValue((state_groups_map[new_state_group], delta_ids))
# Ok, we need to defer to the state handler to resolve our state sets.
@@ -639,7 +670,7 @@ class EventsStore(EventsWorkerStore):
room_id, state_groups, events_map, get_events
)
- defer.returnValue(res.state)
+ defer.returnValue((res.state, None))
@defer.inlineCallbacks
def _calculate_state_delta(self, room_id, current_state):
|
