lamber-ken commented on issue #7396: [FLINK-11250][streaming] fix thread lack when StreamTask switched from DEPLOYING to CANCELING URL: https://github.com/apache/flink/pull/7396#issuecomment-451086296 > Why exactly is it a problem that the writer is initialized later? as the junit test says, must checks that tasks emit a proper cancel checkpoint barrier, if a "trigger checkpoint" message comes before they are ready. if the writer is initalized later, the checkpoint barrier can not emit to next operator, because since flink-1.5.0, the message was uniformly broadcasted by the writer. ### flink-1.4.2 [flink-1.4.2-checkpoint](https://github.com/apache/flink/blob/5cf2358881f896db59bf4f013067116b4c26c5b1/flink-streaming-java/src/main/java/org/apache/flink/streaming/runtime/tasks/StreamTask.java#L590) ### after flink-1.5.0 [flink-1.5.0-checkpoint](https://github.com/apache/flink/blob/f6995f01ef748e4992a37defd60197d1ab4bd00e/flink-streaming-java/src/main/java/org/apache/flink/streaming/runtime/tasks/StreamTask.java#L644) ### junit test [StreamTaskCancellationBarrierTest#testEmitCancellationBarrierWhenNotReady](https://github.com/apache/flink/blob/f6995f01ef748e4992a37defd60197d1ab4bd00e/flink-streaming-java/src/test/java/org/apache/flink/streaming/runtime/tasks/StreamTaskCancellationBarrierTest.java#L57)
---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected] With regards, Apache Git Services
