[FLINK-32362] SourceAlignment announceCombinedWatermark period task maybe lost

• Type: Sub-task
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.16.0
• Fix Version/s: 1.18.0, 1.16.3, 1.17.2
• Labels: pull-request-available
• Assignee: Cai Liuyang
• Reporter: Cai Liuyang
• Created: 16/Jun/23 02:15
• Updated: 06/Jul/23 06:56
• Resolved: 05/Jul/23 13:56

Description

When we use sourcealignment，we also found there is another problem that announceCombinedWatermark may throw a exception (like  "subtask 25 is not ready yet to receive events" , this subtask maybe under failover), which will lead the period task not running any more (ThreadPoolExecutor will not schedule the period task if it throw a exception)

I think we should increase the robustness of announceCombinedWatermark function to avoid it throw any exception (if send fail, just wait next send) (code see https://github.com/apache/flink/blob/master/flink-runtime/src/main/java/org/apache/flink/runtime/source/coordinator/SourceCoordinator.java#L199 )

Issue Links

• links to: GitHub Pull Request #22806
• links to: GitHub Pull Request #22953
• links to: GitHub Pull Request #22954