Github user aljoscha commented on the issue:
https://github.com/apache/flink/pull/5125
What's a bit strange is that other input/output related metrics are created
in `OperatorIOMetricGroup` and then handed to the `Outputs` while the watermark
gauges are created in the `Outputs` and th
Github user zentol commented on the issue:
https://github.com/apache/flink/pull/5125
There are a few reason for that:
1) It keeps the `Outputs` immutable. We need all metrics to be available up
front before creating the output, but since the OperatorIOMetricGroup is
created i