## What is the purpose of the change

The JobManagerRunner creation can be a blocking operation, e.g. if the 
CheckpointCoordinator
needs to access a FileSystem. Therefore, this operation should not be executed 
in the main thread
of the Dispatcher in order to not block this component.

## Brief change log

- Store `CompletableFuture<JobManagerRunner>` in 
`Dispatcher#jobManagerRunnerFutures`
- Made the creation of the `JobManagerRunner` asynchronous

## Verifying this change

- Added `DispatcherTest#testBlockingJobManagerRunner` and 
`DispatcherTest#testFailingJobManagerRunnerCleanup`

## 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: (yes)
  - 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)


[ Full content available at: https://github.com/apache/flink/pull/6699 ]
This message was relayed via gitbox.apache.org for [email protected]

Reply via email to