Github user tweise commented on the issue:
https://github.com/apache/flink/pull/5634
@tzulitai @StephanEwen the current idleness detection in the source context
isn't a replacement for what is required to deal with an inactive partition (or
Kinesis shard). When a connector subtask consumes multiple partitions and one
is idle, then it should be possible to still generate a watermark. This can
only be solved outside of the connector when the multiple source partitions are
visible (like it would be for an operator with multiple input streams).
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