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ASF GitHub Bot commented on FLINK-3375: --------------------------------------- Github user kl0u commented on the pull request: https://github.com/apache/flink/pull/1839#issuecomment-203354870 This PR is for FLINK-3375. Please review. > Allow Watermark Generation in the Kafka Source > ---------------------------------------------- > > Key: FLINK-3375 > URL: https://issues.apache.org/jira/browse/FLINK-3375 > Project: Flink > Issue Type: Improvement > Components: Kafka Connector > Affects Versions: 1.0.0 > Reporter: Stephan Ewen > Assignee: Kostas Kloudas > Fix For: 1.0.0 > > > It is a common case that event timestamps are ascending inside one Kafka > Partition. Ascending timestamps are easy for users, because they are handles > by ascending timestamp extraction. > If the Kafka source has multiple partitions per source task, then the records > become out of order before timestamps can be extracted and watermarks can be > generated. > If we make the FlinkKafkaConsumer an event time source function, it can > generate watermarks itself. It would internally implement the same logic as > the regular operators that merge streams, keeping track of event time > progress per partition and generating watermarks based on the current > guaranteed event time progress. -- This message was sent by Atlassian JIRA (v6.3.4#6332)