Hi, There should be no window or trigger object kept per window.
Aljoscha > On 15. Apr 2019, at 10:22, Fabian Hueske <fhue...@gmail.com> wrote: > > Hi, > > Aljoscha know the implementation best (since he implemented it). > > From my understanding (Aljoscha please correct me if I'm wrong), all Flink > managed state is removed (given that user-defined state is correctly cleaned > up). > However, for each key, a window and a trigger object might be kept (this is > the part I'm not sure about). > This might cause memory issues if the keyspace is very large and "moving" > (keys which are only used for a short period of time, e.g., session keys). > Eventually, a TM would fail causing job recovery. During recovery, only the > Flink managed state is restored and the TM would have free memory again. > > Best, Fabian > > > Am Fr., 12. Apr. 2019 um 19:58 Uhr schrieb M Singh <mans2si...@yahoo.com > <mailto:mans2si...@yahoo.com>>: > Hi Fabian/Guowei: > > Thanks for your pointers. > > Fabian, as you pointed out, global window is never completely removed since > it's end time is Long.MAX_VALUE, and that is my concern. So, is there any > other way of clean up the now purged global windows ? > > Thanks again. > > > > On Thursday, April 11, 2019, 4:16:24 AM EDT, Fabian Hueske <fhue...@gmail.com > <mailto:fhue...@gmail.com>> wrote: > > > Hi, > > As far as I know, a window is only completely removed when time (event or > processing time, depending on the window type) passes the window's end > timestamp. > Since, GlobalWindow's end timestamp is Long.MAX_VALUE, it is never completely > removed. > I'm not 100% sure what state is kept around. It might not be keyed state but > just objects on the heap but not absolutely sure. > > Aljoscha (in CC) should know the details here. > > Best, Fabian > > Am Do., 11. Apr. 2019 um 08:07 Uhr schrieb Guowei Ma <guowei....@gmail.com > <mailto:guowei....@gmail.com>>: > Hi, > I think you could return a proper TriggerResult, which defines how to deal > with the window elements after computing a window in your trigger > implementation. You could find the detail information from the doc[1]. > > 1. > https://ci.apache.org/projects/flink/flink-docs-release-1.8/dev/stream/operators/windows.html#fire-and-purge > > <https://ci.apache.org/projects/flink/flink-docs-release-1.8/dev/stream/operators/windows.html#fire-and-purge> > Best, > Guowei > > > M Singh <mans2si...@yahoo.com <mailto:mans2si...@yahoo.com>> 于2019年4月11日周四 > 上午1:42写道： > Hi: > > I have a use case where I need to create a global window where I need to wait > for unknown time for certain events for a particular key. I understand that > I can create a global window and use a custom trigger to initiate the > function computation. But I am not sure how to destroy the window after the > triggering conditions is satisfied and the the events are purged. > > If there is any better way of dealing with this situation, please let me know. > > Thanks > > Mans
