diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py
index 5cd853d85ec43e5a928f0df07624efc7eb9e573d..ced6fab16f838fc9214c1502ed7d9c3e75ed313a 100644
--- a/synapse/handlers/federation.py
+++ b/synapse/handlers/federation.py
@@ -247,6 +247,11 @@ class FederationHandler(BaseHandler):
             if set(e_id for e_id, _ in ev.prev_events) - event_ids
         ]
 
+        logger.info(
+            "backfill: Got %d events with %d edges",
+            len(events), len(edges),
+        )
+
         # For each edge get the current state.
 
         auth_events = {}