Merge branch 'develop' into avoid_duplicate_filters

1 files changed, 15 insertions, 0 deletions

diff --git a/synapse/util/caches/stream_change_cache.py b/synapse/util/caches/stream_change_cache.py

index 70fe00ce0b..609625b322 100644
--- a/synapse/util/caches/stream_change_cache.py
+++ b/synapse/util/caches/stream_change_cache.py
@@ -89,6 +89,21 @@ class StreamChangeCache(object):
 
         return result
 
+    def has_any_entity_changed(self, stream_pos):
+        """Returns if any entity has changed
+        """
+        assert type(stream_pos) is int
+
+        if stream_pos >= self._earliest_known_stream_pos:
+            self.metrics.inc_hits()
+            keys = self._cache.keys()
+            i = keys.bisect_right(stream_pos)
+
+            return i < len(keys)
+        else:
+            self.metrics.inc_misses()
+            return True
+
     def get_all_entities_changed(self, stream_pos):
         """Returns all entites that have had new things since the given
         position. If the position is too old it will return None.