GitHub user zentol opened a pull request:
https://github.com/apache/flink/pull/5125
[WIP][FLINK-4812][metrics] Expose currentLowWatermark for all operators
This is a revised WIP version of #5100.
## What is the purpose of the change
With this PR all operators expose the current input/output watermark
through the metric system.
This PR is not complete; it is missing tests and documentation, but I want
to gather feedback on the solution first.
## Brief change log
* input watermark metrics for the head operator are measure in the stream
input processor classes
* the remaining watermark metrics are measure in the Output classes
* operators can define whether input/output watermarks should override the
other (for example, sources override the input watermark with the output
watermark).
* watermark metrics are setup for the most part in the `OperatorChain`,
with the exception of 2 additional metrics for two input operators
(currentInput[1|2]Watermark)
@aljoscha
You can merge this pull request into a Git repository by running:
$ git pull https://github.com/zentol/flink 4812c
Alternatively you can review and apply these changes as the patch at:
https://github.com/apache/flink/pull/5125.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 #5125
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commit 9ab939d0cf5d0ea7f5f6feb2a5ad7e5b3030bbaf
Author: zentol <ches...@apache.org>
Date: 2017-12-05T13:20:29Z
[FLINK-4812][metrics] Expose currentLowWatermark for all operators
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