Details
-
Bug
-
Resolution: Fixed
-
Critical
-
7.2.4
-
Untriaged
-
0
-
Unknown
Description
Exception seen as follows
CRITICAL Caught unhandled std::exception-derived exception. what(): Monotonic<m> (ActiveStream(eq_dcpq:"i":"AE23217F111AEFB7/0528E92BBF8F1215","a":"kafka-connector/4.1.13 (blah) java-dcp-client/0.47.0 Java/11.0.20 (Azul Systems, Inc.; OpenJDK 64-Bit Server VM; 11.0.20+8-LTS)" vb:121)::lastReadSeqno) invariant failed: new value (555) breaks invariant on current value (555)
|
And this was generated from the assignment in ::snapshot
This was only ever observed on a Kafka DCP connection, and seen twice. Analysis strongly suggests that at the time Kafka was connected to a replica vbucket.
Possibly this was a vbucket that rolled back (the original issue occurred outside of memcached.log coverage), but yet to reproduce in unit tests anything similar. Timestamps from ns_server shows the exception occurred some minutes after vbucket became replica, so maybe not rollback related.
No further insights to the cause known.
Attachments
For Gerrit Dashboard: MB-62847 | ||||||
---|---|---|---|---|---|---|
# | Subject | Branch | Project | Status | CR | V |
213361,3 | MB-62847: Fix DCP premature SeqnoAdvance when only set_vb_state is queued | neo | kv_engine | Status: MERGED | +2 | +1 |
213466,3 | MB-62847, MB-62835, MB-62727: Merge 'couchbase/neo' into 'couchbase/trinity' | trinity | kv_engine | Status: MERGED | +2 | +1 |
213726,2 | MB-62847: Destroy mock cookie when its no longer needed | trinity | kv_engine | Status: MERGED | +2 | +1 |
213737,1 | Merge remote-tracking branch 'couchbase/trinity' into cypher | cypher | kv_engine | Status: MERGED | +2 | +1 |
213738,1 | Merge remote-tracking branch 'couchbase/cypher' into trunk | master | kv_engine | Status: MERGED | +2 | +1 |