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Tzu-Li (Gordon) Tai commented on FLINK-4616: -------------------------------------------- We decided that we should let the user function code be free of responsibility of checkpointing watermarks, and let user code simply leave that to the streaming internals (checkpointed by window operators, and perhaps also by source operators). Therefore, this would not be need in the Kafka consumer. > Kafka consumer doesn't store last emmited watermarks per partition in state > --------------------------------------------------------------------------- > > Key: FLINK-4616 > URL: https://issues.apache.org/jira/browse/FLINK-4616 > Project: Flink > Issue Type: Bug > Components: Kafka Connector > Affects Versions: 1.1.1 > Reporter: Yuri Makhno > Assignee: Roman Maier > > Kafka consumers stores in state only kafka offsets and doesn't store last > emmited watermarks, this may go to wrong state when checkpoint is restored: > Let's say our watermark is (timestamp - 10) and in case we have the following > messages queue results will be different after checkpoint restore and during > normal processing: > A(ts = 30) > B(ts = 35) > ------ checkpoint goes here > C(ts=15) -- this one should be filtered by next time window > D(ts=60) -- This message was sent by Atlassian JIRA (v6.3.15#6346)