AsyncIO/QueryableStateClient hanging with high parallelism

[Yassine MARZOUGUI]

Hi all,

I set up a job with simple queryable state sink and tried to query it from another job using the new Async I/O API. Everything worked as expected, except when I tried to increase the parallelism of the querying job it hanged.

As you can see in the attached image, when the parallism is 5 (even <5) the job finishes within 5 seconds, but when it is >5 it hangs. Any Idea of what might be causing this behaviour? Thank you.

Best,

Yassine

[Yassine MARZOUGUI]

I think I found the reason for what happened. The way I used the QueryableStateClient is that I wrapped scala.concurrent.Future in a FlinkFuture and then called FlinkFuture.thenAccept. It turns out thenAccept doesn't throw exceptions and when an exception happens (which likely happened once I inreased the parallelism) the job simply doesn't finish. I solved the problem by using resultFuture.get()which araised the appropriate exceptions when they happens and failed the job.

Best,

Yassine

2017-03-06 15:53 GMT+01:00 Yassine MARZOUGUI <[hidden email]>:

Hi all,

I set up a job with simple queryable state sink and tried to query it from another job using the new Async I/O API. Everything worked as expected, except when I tried to increase the parallelism of the querying job it hanged.

As you can see in the attached image, when the parallism is 5 (even <5) the job finishes within 5 seconds, but when it is >5 it hangs. Any Idea of what might be causing this behaviour? Thank you.

Best,

Yassine