Fix federation inbound age metric. (#10355)

We should be reporting the age rather than absolute timestamp.
2021-07-13 11:33:15 +01:00 · 2021-07-13 11:33:15 +01:00 · 879d8c1ee1
parent c2c364f27f
commit 879d8c1ee1
2 changed files with 4 additions and 1 deletions
--- a/changelog.d/10355.bugfix
+++ b/changelog.d/10355.bugfix
@ -0,0 +1 @@
+Fix newly added `synapse_federation_server_oldest_inbound_pdu_in_staging` prometheus metric to measure age rather than timestamp.
--- a/synapse/storage/databases/main/event_federation.py
+++ b/synapse/storage/databases/main/event_federation.py
@ -1230,7 +1230,9 @@ class EventFederationWorkerStore(EventsWorkerStore, SignatureWorkerStore, SQLBas
                "SELECT coalesce(min(received_ts), 0) FROM federation_inbound_events_staging"
            )

-            (age,) = txn.fetchone()
+            (received_ts,) = txn.fetchone()
+
+            age = self._clock.time_msec() - received_ts

            return count, age
				`@ -0,0 +1 @@`
				Fix newly added `synapse_federation_server_oldest_inbound_pdu_in_staging` prometheus metric to measure age rather than timestamp.