Hi, I am trying to achieve a stream-to-stream join with big windows and are searching for a way to clean up state of old keys. I am already using a RichCoProcessFunction
I found there is already an existing ticket https://issues.apache.org/jira/browse/FLINK-3089 but I have doubts that a registration of a timer for every incoming event is feasible as the timers seem to reside in an in-memory queue. The task is somewhat similar to the following blog post: http://devblog.mediamath.com/real-time-streaming-attribution-using-apache-flink Is the implementation of a custom window operator a necessity for achieving such functionality Thanks a lot, Johannes
