GitHub user tillrohrmann opened a pull request: https://github.com/apache/flink/pull/6398
[FLINK-9923][tests] Harden OneInputStreamTaskTest#testWatermarkMetrics ## What is the purpose of the change Convert the WatermarkGauge's field currentWatermark from long to AtomicLong because writes and reads can happen from different threads. Unfortunately, we cannot simply make it volatile because not all JVM support atomic writes to longs. cc @zentol. ## Does this pull request potentially affect one of the following parts: - Dependencies (does it add or upgrade a dependency): (no) - The public API, i.e., is any changed class annotated with `@Public(Evolving)`: (no) - The serializers: (no) - The runtime per-record code paths (performance sensitive): (no) - Anything that affects deployment or recovery: JobManager (and its components), Checkpointing, Yarn/Mesos, ZooKeeper: (no) - The S3 file system connector: (no) ## Documentation - Does this pull request introduce a new feature? (no) - If yes, how is the feature documented? (not applicable) You can merge this pull request into a Git repository by running: $ git pull https://github.com/tillrohrmann/flink fixOneInpuStreamTaskTest Alternatively you can review and apply these changes as the patch at: https://github.com/apache/flink/pull/6398.patch To close this pull request, make a commit to your master/trunk branch with (at least) the following in the commit message: This closes #6398 ---- commit d46dd6f2ddf76d5dfcb1bed983f31542ddc771a3 Author: Till Rohrmann <trohrmann@...> Date: 2018-07-23T20:25:25Z [FLINK-9923][tests] Harden OneInputStreamTaskTest#testWatermarkMetrics Convert the WatermarkGauge's field currentWatermark from long to AtomicLong because writes and reads can happen from different threads. Unfortunately, we cannot simply make it volatile because not all JVM support atomic writes to longs. ---- ---