Hi Chengzhi, currently, the watermarks of the two streams of a connected stream are forcibly synchronized, i.e., the watermark is decided by the stream with a larger delay. Thus the window trigger is also affected by this mechanism.
As a workaround, you could try to add (or subtract) a static time offset to one of your streams, which can make them more “close” to each other. Best, Xingcan > On 13 Apr 2018, at 11:48 PM, Chengzhi Zhao <w.zhaocheng...@gmail.com> wrote: > > Hi, flink community, > > I had an issue with slow watermark advances and needs some help here. So here > is what happened: I have two streams -- A and B, and they perform co-process > to join together and A has another steam as output. > > A --> Output > B --> (Connect A) --> Output > > I used BoundedOutOfOrdernessGenerator [1] with both A and B stream with 2 > hours delay. The low watermark of A and output sink is within 2 hours window, > however, the co-process end up with 10 hours low watermark late. > > My setup is I am using file system as source, so every 15 mins there will be > files been drop to a directory and flink pick them up from there. > > Please advise and appreciate it in advance! > > [1] > https://ci.apache.org/projects/flink/flink-docs-release-1.4/dev/event_timestamps_watermarks.html#with-periodic-watermarks > > <https://ci.apache.org/projects/flink/flink-docs-release-1.4/dev/event_timestamps_watermarks.html#with-periodic-watermarks> > > Best, > Chengzhi >
