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Posted to issues@flink.apache.org by GitBox <gi...@apache.org> on 2020/10/04 08:57:15 UTC

[GitHub] [flink] AHeise opened a new pull request #13539: [FLINK-19027][network] Assign exclusive buffers to LocalRecoveredInputChannel.

AHeise opened a new pull request #13539:
URL: https://github.com/apache/flink/pull/13539

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## What is the purpose of the change

If a local channel does not receive a buffer during recovery, a live lock may occur where the local channel cannot recover because it is waiting for a buffer but upstream operators are fully backpressured and cannot release a buffer.
It's important to treat LocalRecoveredInputChannel like RemoteInputChannels and assign exclusive buffers for recovery to avoid this situation.

## Brief change log

- Assign exclusive buffers to LocalRecoveredInputChannel.
- Ensure SingleInputGateTest does not swallow exceptions during cleanup.
- Revert https://github.com/apache/flink/pull/13532 as the test failure actually revealed the live lock.

## Verifying this change

Adjusted a few unit tests.
Already covered and reveleaed by UnalignedCheckpointITCase.

## 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, Kubernetes/Yarn/Mesos, ZooKeeper: (yes / **no** / don't know)
- The S3 file system connector: (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)

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