The continuation trigger is automatically used after the first group by key with a trigger. It is an attempt to trigger "as fast as reasonable" based on the original trigger. For example, if the trigger was 5 minutes after the hour (so aligned to an hour and then delayed by 5m) it wouldn't be good for every group by key to reintroduce the same delay. Instead it uses synchronized processing time to wait for all upstream firings of the same target time to fire. This ensures that all of the aligned triggers have been processed but non delay beyond that is introduced.
Are there use cases for a user using synchronized processing time directly? On Sun, Feb 19, 2017, 2:30 PM Amit Sela <[email protected]> wrote: > Hi all, > > I was wondering how to use AfterSynchronizedProcessingTime trigger. for > processing time triggers there's the > AfterProcessingTime.pastFirstElementInPane() API but I've noticed that > AfterSynchronizedProcessingTime constructor is only called from a a > continuation trigger. > I wonder if someone could explain how should pipeline authors use this > trigger, and maybe a general explanation about processing time triggers > since (as far as I could find) most of existing > documentations/presentations/talks are focused on watermark-based triggers. > > Thanks, > Amit >
