GitHub user pnowojski opened a pull request: https://github.com/apache/flink/pull/4841
[FLINK-7368][metrics] Backport synchronization fix for MetricStore ## What is the purpose of the change This backports adding missing synchronization on MetricStore ## Verifying this change This change is already covered by existing tests, such as *MetricFetcherTest*. ## Does this pull request potentially affect one of the following parts: - Dependencies (does it add or upgrade a dependency): (yes / **no**) - The public API, i.e., is any changed class annotated with `@Public(Evolving)`: (yes / **no**) - The serializers: (yes / **no** / don't know) - The runtime per-record code paths (performance sensitive): (yes / **no** / don't know) - Anything that affects deployment or recovery: JobManager (and its components), Checkpointing, Yarn/Mesos, ZooKeeper: (yes / **no** / don't know) ## Documentation - Does this pull request introduce a new feature? (yes / **no**) - If yes, how is the feature documented? (**not applicable** / docs / JavaDocs / not documented) You can merge this pull request into a Git repository by running: $ git pull https://github.com/pnowojski/flink flink7368-1.3 Alternatively you can review and apply these changes as the patch at: https://github.com/apache/flink/pull/4841.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 #4841 ---- commit 4783633167b3008e66da97076b5e38e89e85e2bd Author: Piotr Nowojski <piotr.nowoj...@gmail.com> Date: 2017-10-16T15:17:26Z [FLINK-7368][metrics] Backport synchronization fix for MetricStore ---- ---