If something requires Beam to register a new state each time, then this is tricky, because currently you cannot unregister states from Flink.
@Yu @Yun I remember chatting about this (allowing to explicitly unregister states so they get dropped from successive checkpoints) at some point, but I could not find a jira ticket for this. Do you remember what the status of that discussion is? On Thu, Apr 16, 2020 at 6:37 PM Stephen Patel <merli...@gmail.com> wrote: > I posted to the beam mailing list: > https://lists.apache.org/thread.html/rb2ebfad16d85bcf668978b3defd442feda0903c20db29c323497a672%40%3Cuser.beam.apache.org%3E > > I think this is related to a Beam feature called RequiresStableInput > (which my pipeline is using). It will create a new operator (or keyed) > state per checkpoint. I'm not sure that there are any parameters that I > have control over to tweak it's behavior (apart from increasing the > checkpoint interval to let the pipeline run longer before building up that > many states). > > Perhaps this is something that can be fixed (maybe by unregistering > Operator States after they aren't used any more in the RequiresStableInput > code). It seems to me that this isn't a Flink issue, but rather a Beam > issue. > > Thanks for pointing me in the right direction. > > On Thu, Apr 16, 2020 at 11:29 AM Yun Tang <myas...@live.com> wrote: > >> Hi Stephen >> >> I think the state name [1] which would be changed every time might the >> root cause. I am not familiar with Beam code, would it be possible to >> create so many operator states? Did you configure some parameters wrongly? >> >> >> [1] >> https://github.com/apache/beam/blob/4fc924a8193bb9495c6b7ba755ced576bb8a35d5/runners/flink/src/main/java/org/apache/beam/runners/flink/translation/wrappers/streaming/stableinput/BufferingDoFnRunner.java#L95 >> >> Best >> Yun Tang >> ------------------------------ >> *From:* Stephen Patel <merli...@gmail.com> >> *Sent:* Thursday, April 16, 2020 22:30 >> *To:* Yun Tang <myas...@live.com> >> *Cc:* user@flink.apache.org <user@flink.apache.org> >> *Subject:* Re: Streaming Job eventually begins failing during >> checkpointing >> >> Correction. I've actually found a place where it potentially might be >> creating a new operator state per checkpoint: >> >> https://github.com/apache/beam/blob/4fc924a8193bb9495c6b7ba755ced576bb8a35d5/runners/flink/src/main/java/org/apache/beam/runners/flink/translation/wrappers/streaming/stableinput/BufferingDoFnRunner.java#L91-L105 >> https://github.com/apache/beam/blob/4fc924a8193bb9495c6b7ba755ced576bb8a35d5/runners/flink/src/main/java/org/apache/beam/runners/flink/translation/wrappers/streaming/stableinput/BufferingDoFnRunner.java#L141-L149 >> >> This gives me something I can investigate locally at least. >> >> On Thu, Apr 16, 2020 at 9:03 AM Stephen Patel <merli...@gmail.com> wrote: >> >> I can't say that I ever call that directly. The beam library that I'm >> using does call it in a couple places: >> https://github.com/apache/beam/blob/v2.14.0/runners/flink/src/main/java/org/apache/beam/runners/flink/translation/wrappers/streaming/io/UnboundedSourceWrapper.java#L422-L429 >> >> But it seems to be the same descriptor every time. Is that limit per >> operator? That is, can each operator host up to 32767 operator/broadcast >> states? I assume that's by name? >> >> On Wed, Apr 15, 2020 at 10:46 PM Yun Tang <myas...@live.com> wrote: >> >> Hi Stephen >> >> This is not related with RocksDB but with default on-heap operator state >> backend. From your exception stack trace, you have created too many >> operator states (more than 32767). >> How do you call context.getOperatorStateStore().getListState or >> context.getOperatorStateStore().getBroadcastState ? Did you pass a >> different operator state descriptor each time? >> >> Best >> Yun Tang >> ------------------------------ >> *From:* Stephen Patel <merli...@gmail.com> >> *Sent:* Thursday, April 16, 2020 2:09 >> *To:* user@flink.apache.org <user@flink.apache.org> >> *Subject:* Streaming Job eventually begins failing during checkpointing >> >> I've got a flink (1.8.0, emr-5.26) streaming job running on yarn. It's >> configured to use rocksdb, and checkpoint once a minute to hdfs. This job >> operates just fine for around 20 days, and then begins failing with this >> exception (it fails, restarts, and fails again, repeatedly): >> >> 2020-04-15 13:15:02,920 INFO >> org.apache.flink.runtime.checkpoint.CheckpointCoordinator - Triggering >> checkpoint 32701 @ 1586956502911 for job 9953424f21e240112dd23ab4f8320b60. >> 2020-04-15 13:15:05,762 INFO >> org.apache.flink.runtime.checkpoint.CheckpointCoordinator - Completed >> checkpoint 32701 for job 9953424f21e240112dd23ab4f8320b60 (795385496 bytes >> in 2667 ms). >> 2020-04-15 13:16:02,919 INFO >> org.apache.flink.runtime.checkpoint.CheckpointCoordinator - Triggering >> checkpoint 32702 @ 1586956562911 for job 9953424f21e240112dd23ab4f8320b60. >> 2020-04-15 13:16:03,147 INFO >> org.apache.flink.runtime.executiongraph.ExecutionGraph - >> <operator_name> (1/2) (f4737add01961f8b42b8eb4e791b83ba) switched from >> RUNNING to FAILED. >> AsynchronousException{java.lang.Exception: Could not materialize >> checkpoint 32702 for operator <operator_name> (1/2).} >> at >> org.apache.flink.streaming.runtime.tasks.StreamTask$AsyncCheckpointExceptionHandler.tryHandleCheckpointException(StreamTask.java:1153) >> at >> org.apache.flink.streaming.runtime.tasks.StreamTask$AsyncCheckpointRunnable.handleExecutionException(StreamTask.java:947) >> at >> org.apache.flink.streaming.runtime.tasks.StreamTask$AsyncCheckpointRunnable.run(StreamTask.java:884) >> at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) >> at java.util.concurrent.FutureTask.run(FutureTask.java:266) >> at >> java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) >> at >> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) >> at java.lang.Thread.run(Thread.java:748) >> Caused by: java.lang.Exception: Could not materialize checkpoint 32702 >> for operator <operator_name> (1/2). >> at >> org.apache.flink.streaming.runtime.tasks.StreamTask$AsyncCheckpointRunnable.handleExecutionException(StreamTask.java:942) >> ... 6 more >> Caused by: java.util.concurrent.ExecutionException: >> java.lang.IllegalArgumentException >> at java.util.concurrent.FutureTask.report(FutureTask.java:122) >> at java.util.concurrent.FutureTask.get(FutureTask.java:192) >> at >> org.apache.flink.runtime.concurrent.FutureUtils.runIfNotDoneAndGet(FutureUtils.java:394) >> at >> org.apache.flink.streaming.api.operators.OperatorSnapshotFinalizer.<init>(OperatorSnapshotFinalizer.java:53) >> at >> org.apache.flink.streaming.runtime.tasks.StreamTask$AsyncCheckpointRunnable.run(StreamTask.java:853) >> ... 5 more >> Caused by: java.lang.IllegalArgumentException >> at >> org.apache.flink.util.Preconditions.checkArgument(Preconditions.java:123) >> at >> org.apache.flink.runtime.state.OperatorBackendSerializationProxy.<init>(OperatorBackendSerializationProxy.java:68) >> at >> org.apache.flink.runtime.state.DefaultOperatorStateBackendSnapshotStrategy$1.callInternal(DefaultOperatorStateBackendSnapshotStrategy.java:138) >> at >> org.apache.flink.runtime.state.DefaultOperatorStateBackendSnapshotStrategy$1.callInternal(DefaultOperatorStateBackendSnapshotStrategy.java:108) >> at >> org.apache.flink.runtime.state.AsyncSnapshotCallable.call(AsyncSnapshotCallable.java:75) >> at java.util.concurrent.FutureTask.run(FutureTask.java:266) >> at >> org.apache.flink.runtime.concurrent.FutureUtils.runIfNotDoneAndGet(FutureUtils.java:391) >> ... 7 more >> >> This application configured to retain external checkpoints. When I >> attempt to restart from the last successful checkpoint, it will fail with >> the same error on the first checkpoint that happens after the restart. >> >> I haven't been able to find out why this might be. The source code >> doesn't seem particularly informative to my eyes: >> https://github.com/apache/flink/blob/release-1.8.0/flink-runtime/src/main/java/org/apache/flink/runtime/state/OperatorBackendSerializationProxy.java#L68 >> >> Has anyone else seen anything like this? >> >>
