Merge pull request #2248 from matrix-org/erikj/state_fixup

Faster cache for get_joined_hosts

1 files changed, 24 insertions, 28 deletions

diff --git a/synapse/state.py b/synapse/state.py
index dffa79e4c9..a98145598f 100644
--- a/synapse/state.py
+++ b/synapse/state.py
@@ -170,9 +170,7 @@ class StateHandler(object):
             latest_event_ids = yield self.store.get_latest_event_ids_in_room(room_id)
         logger.debug("calling resolve_state_groups from get_current_user_in_room")
         entry = yield self.resolve_state_groups(room_id, latest_event_ids)
-        joined_users = yield self.store.get_joined_users_from_state(
-            room_id, entry.state_id, entry.state
-        )
+        joined_users = yield self.store.get_joined_users_from_state(room_id, entry)
         defer.returnValue(joined_users)
 
     @defer.inlineCallbacks
@@ -181,9 +179,7 @@ class StateHandler(object):
             latest_event_ids = yield self.store.get_latest_event_ids_in_room(room_id)
         logger.debug("calling resolve_state_groups from get_current_hosts_in_room")
         entry = yield self.resolve_state_groups(room_id, latest_event_ids)
-        joined_hosts = yield self.store.get_joined_hosts(
-            room_id, entry.state_id, entry.state
-        )
+        joined_hosts = yield self.store.get_joined_hosts(room_id, entry)
         defer.returnValue(joined_hosts)
 
     @defer.inlineCallbacks
@@ -206,12 +202,12 @@ class StateHandler(object):
         Returns:
             synapse.events.snapshot.EventContext:
         """
-        context = EventContext()
 
         if event.internal_metadata.is_outlier():
             # If this is an outlier, then we know it shouldn't have any current
             # state. Certainly store.get_current_state won't return any, and
             # persisting the event won't store the state group.
+            context = EventContext()
             if old_state:
                 context.prev_state_ids = {
                     (s.type, s.state_key): s.event_id for s in old_state
@@ -230,6 +226,7 @@ class StateHandler(object):
             defer.returnValue(context)
 
         if old_state:
+            context = EventContext()
             context.prev_state_ids = {
                 (s.type, s.state_key): s.event_id for s in old_state
             }
@@ -250,19 +247,13 @@ class StateHandler(object):
             defer.returnValue(context)
 
         logger.debug("calling resolve_state_groups from compute_event_context")
-        if event.is_state():
-            entry = yield self.resolve_state_groups(
-                event.room_id, [e for e, _ in event.prev_events],
-                event_type=event.type,
-                state_key=event.state_key,
-            )
-        else:
-            entry = yield self.resolve_state_groups(
-                event.room_id, [e for e, _ in event.prev_events],
-            )
+        entry = yield self.resolve_state_groups(
+            event.room_id, [e for e, _ in event.prev_events],
+        )
 
         curr_state = entry.state
 
+        context = EventContext()
         context.prev_state_ids = curr_state
         if event.is_state():
             context.state_group = self.store.get_next_state_group()
@@ -275,11 +266,14 @@ class StateHandler(object):
             context.current_state_ids = dict(context.prev_state_ids)
             context.current_state_ids[key] = event.event_id
 
-            context.prev_group = entry.prev_group
-            context.delta_ids = entry.delta_ids
-            if context.delta_ids is not None:
-                context.delta_ids = dict(context.delta_ids)
-                context.delta_ids[key] = event.event_id
+            if entry.state_group:
+                context.prev_group = entry.state_group
+                context.delta_ids = {
+                    key: event.event_id
+                }
+            elif entry.prev_group:
+                context.prev_group = entry.prev_group
+                context.delta_ids = entry.delta_ids
         else:
             if entry.state_group is None:
                 entry.state_group = self.store.get_next_state_group()
@@ -295,7 +289,7 @@ class StateHandler(object):
 
     @defer.inlineCallbacks
     @log_function
-    def resolve_state_groups(self, room_id, event_ids, event_type=None, state_key=""):
+    def resolve_state_groups(self, room_id, event_ids):
         """ Given a list of event_ids this method fetches the state at each
         event, resolves conflicts between them and returns them.
 
@@ -320,11 +314,13 @@ class StateHandler(object):
         if len(group_names) == 1:
             name, state_list = state_groups_ids.items().pop()
 
+            prev_group, delta_ids = yield self.store.get_state_group_delta(name)
+
             defer.returnValue(_StateCacheEntry(
                 state=state_list,
                 state_group=name,
-                prev_group=name,
-                delta_ids={},
+                prev_group=prev_group,
+                delta_ids=delta_ids,
             ))
 
         with (yield self.resolve_linearizer.queue(group_names)):
@@ -377,11 +373,11 @@ class StateHandler(object):
 
             prev_group = None
             delta_ids = None
-            for old_group, old_ids in state_groups_ids.items():
-                if not set(new_state.iterkeys()) - set(old_ids.iterkeys()):
+            for old_group, old_ids in state_groups_ids.iteritems():
+                if not set(new_state) - set(old_ids):
                     n_delta_ids = {
                         k: v
-                        for k, v in new_state.items()
+                        for k, v in new_state.iteritems()
                         if old_ids.get(k) != v
                     }
                     if not delta_ids or len(n_delta_ids) < len(delta_ids):