Discard RDATA from already seen positions. (#7648)

1 files changed, 5 insertions, 0 deletions

diff --git a/synapse/app/generic_worker.py b/synapse/app/generic_worker.py

index f3ec2a34ec..53c488d211 100644
--- a/synapse/app/generic_worker.py
+++ b/synapse/app/generic_worker.py
@@ -738,6 +738,11 @@ class GenericWorkerReplicationHandler(ReplicationDataHandler):
         except Exception:
             logger.exception("Error processing replication")
 
+    async def on_position(self, stream_name: str, instance_name: str, token: int):
+        await super().on_position(stream_name, instance_name, token)
+        # Also call on_rdata to ensure that stream positions are properly reset.
+        await self.on_rdata(stream_name, instance_name, token, [])
+
     def stop_pusher(self, user_id, app_id, pushkey):
         if not self.notify_pushers:
             return