add some logging to the rooms stats updates, to try to track down a flaky test (#6167)

changelog.d/6167.misc

@@ -0,0 +1 @@
+Add some logging to the rooms stats updates, to try to track down a flaky test.

synapse/handlers/stats.py

@@ -293,6 +293,7 @@ class StatsHandler(StateDeltasHandler):
                 room_state["guest_access"] = event_content.get("guest_access")
 
         for room_id, state in room_to_state_updates.items():
+            logger.info("Updating room_stats_state for %s: %s", room_id, state)
             yield self.store.update_room_state(room_id, state)
 
         return room_to_stats_deltas, user_to_stats_deltas

synapse/storage/stats.py

@@ -332,6 +332,9 @@ class StatsStore(StateDeltasStore):
         def _bulk_update_stats_delta_txn(txn):
             for stats_type, stats_updates in updates.items():
                 for stats_id, fields in stats_updates.items():
+                    logger.info(
+                        "Updating %s stats for %s: %s", stats_type, stats_id, fields
+                    )
                     self._update_stats_delta_txn(
                         txn,
                         ts=ts,