Hi guys, I'm going a PoC with Flink and I was wondering if you could help me.
I've asked a question here https://stackoverflow.com/questions/55907954/flink-session-window-sink-timestamp-not-progressing with some images. However, in summary my question is this; why doesn't my session window progress?
It works great when I run it against historical data, but when I run it against a streaming data source (pub/sub) it sometimes gets stuck. In this case, it got stuck at exactly 12:00 UTC.
My window is a session window, but one where I bump the last 'edge' of the window by different amounts depending on what event type it is. Because some events never have other events after them.
You can see the problem the easiest in these graphs, specifically the one that stops at 14:00 CEST (12:00 UTC) - with green bars.
This graph shows the low-watermark progressing throughout the node in the middle (which is also a sink); and this holds for all the nodes in the graph. However, the session windowing doesn't progress, despite the low-watermark progressing.
Regards, Henrik
