Re: Kafka partition alignment for event time

Posted by shikhar on
URL: http://deprecated-apache-flink-user-mailing-list-archive.369.s1.nabble.com/Kafka-partition-alignment-for-event-time-tp4782p4817.html

Hi Fabian,

Sorry, I should have been clearer. What I meant (or now know!) by duplicate emits is that since the watermark is progressing more rapidly than the state of the offsets on some partitions due to the source multiplexing more than 1 partition, when messages from the lagging partitions are passed on to further operators specifically time-based windowing they get emitted immediately, resulting in duplicate windows (https://issues.apache.org/jira/browse/FLINK-2870).