Hi, Let's consider two operators: A (parallelism=2) and B (parallelism=1). B has two input partitions, B_A1 and B_A2, which are connected to A1 and A2 respectively.
At some point, - B_A1's watermark : 12 - B_A2's watermark : 10 - B's event-time clock : 10 = min(12, 10) - B has registered a timer at 12 - No data will be fed into the pipeline for the next few hours, but I want the timer to be fired after a few seconds if no data is coming. After adopting a watermark strategy explained in [1], I found that the timer is fired as wished! That's awesome! But I want to know what happens inside in detail. Based on my current understanding of how watermark is calculated [2], I cannot come up with what happens inside when idleness is considered. If B_A2 is marked idle earlier than B_A1, is B's event-time clock calculated as min(12, MAX_WATERMARK)? Thanks, Dongwon [1] https://ci.apache.org/projects/flink/flink-docs-stable/dev/event_timestamps_watermarks.html#dealing-with-idle-sources [2] https://ci.apache.org/projects/flink/flink-docs-stable/dev/event_timestamps_watermarks.html#how-operators-process-watermarks [3] https://cwiki.apache.org/confluence/display/FLINK/FLIP-126%3A+Unify+%28and+separate%29+Watermark+Assigners
