sjvanrossum opened a new pull request, #39556: URL: https://github.com/apache/beam/pull/39556
This fixes the same issue as #39458 by having the `ScheduledExecutorService` establish a happens-before relationship between the submitting thread and executing thread, which appears to be missing for the common `ForkJoinPool` executor used by `MoreFutures.runAsync(ThrowingRunnable)` based on testing `TFRecordSchemaTransformProviderTest` with TSAN enabled. TSAN reports data races between the processing thread's write(s) to the `Writer` and the background thread's closing and/or cleanup of the `Writer` in [`CRC32`](https://docs.oracle.com/javase/8/docs/api/java/util/zip/CRC32.html) calls made by a gzip compressor. `Writer` can be patched to establish acquire/release barriers between open and close/cleanup (e.g., by marking `channel` as `volatile` and adjusting reads/writes accordingly), but since `write` is `abstract` and the underlying `WritableByteChannel` is passed to implementations in `prepareWrite` instead of being accessed through its member field on the super class there's no point between any call to `write` and `close` which would insert the required memory barriers. I can't think of any other tricks to make `Writer` inherently thread safe without modifying its public API as is already proposed in #39458. It is thread compatible at least, so it just needs external synchronization to play nice. Replacing the common `ForkJoinPool` with the harness `ScheduledExecutorService` as the executor for closing writers should be enough to take care of that. ------------------------ Thank you for your contribution! Follow this checklist to help us incorporate your contribution quickly and easily: - [ ] Mention the appropriate issue in your description (for example: `addresses #123`), if applicable. This will automatically add a link to the pull request in the issue. If you would like the issue to automatically close on merging the pull request, comment `fixes #<ISSUE NUMBER>` instead. - [ ] Update `CHANGES.md` with noteworthy changes. - [ ] If this contribution is large, please file an Apache [Individual Contributor License Agreement](https://www.apache.org/licenses/icla.pdf). See the [Contributor Guide](https://beam.apache.org/contribute) for more tips on [how to make review process smoother](https://github.com/apache/beam/blob/master/CONTRIBUTING.md#make-the-reviewers-job-easier). To check the build health, please visit [https://github.com/apache/beam/blob/master/.test-infra/BUILD_STATUS.md](https://github.com/apache/beam/blob/master/.test-infra/BUILD_STATUS.md) GitHub Actions Tests Status (on master branch) ------------------------------------------------------------------------------------------------ [](https://github.com/apache/beam/actions?query=workflow%3A%22Build+python+source+distribution+and+wheels%22+branch%3Amaster+event%3Aschedule) [](https://github.com/apache/beam/actions?query=workflow%3A%22Python+Tests%22+branch%3Amaster+event%3Aschedule) [](https://github.com/apache/beam/actions?query=workflow%3A%22Java+Tests%22+branch%3Amaster+event%3Aschedule) [](https://github.com/apache/beam/actions?query=workflow%3A%22Go+tests%22+branch%3Amaster+event%3Aschedule) See [CI.md](https://github.com/apache/beam/blob/master/CI.md) for more information about GitHub Actions CI or the [workflows README](https://github.com/apache/beam/blob/master/.github/workflows/README.md) to see a list of phrases to trigger workflows. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
