pnowojski opened a new pull request, #24794: URL: https://github.com/apache/flink/pull/24794
## What is the purpose of the change Properly initialize initial splits in WatermarkOutputMultiplexer Without this fix, initial splits were registered in the multiplexer only when first record from that split has been emitted. This was leading to incorrectly emitted watermarks, as resulting watermark was not properly combined from the initial splits, but only from the splits that have already emitted at least one record. ## Brief change log Please check individual commit messages ## Verifying this change This bugfix is covered against future regressions by a new test. ## 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, 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) -- 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: issues-unsubscr...@flink.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org