You are viewing a plain text version of this content. The canonical link for it is here.
Posted to commits@beam.apache.org by "Daniel Harper (JIRA)" <ji...@apache.org> on 2017/08/25 12:09:00 UTC
[jira] [Created] (BEAM-2807) NullPointerException during checkpoint
during Flink CoderTypeSerializer phase
Daniel Harper created BEAM-2807:
-----------------------------------
Summary: NullPointerException during checkpoint during Flink CoderTypeSerializer phase
Key: BEAM-2807
URL: https://issues.apache.org/jira/browse/BEAM-2807
Project: Beam
Issue Type: Bug
Components: beam-model
Affects Versions: 2.1.0
Reporter: Daniel Harper
Assignee: Kenneth Knowles
Priority: Blocker
*Beam version:* 2.1.0
*Runner:* FlinkRunner
We're seeing the following exception when checkpointing, which is causing our job to restart
{code}
2017-08-25 09:42:17,658 INFO org.apache.flink.runtime.taskmanager.Task - Combine.perKey(Count) -> ParMultiDo(ToConcurrentStreamResult) -> ParMultiDo(Anonymous) -> ParMultiDo(ApplyShardingKey) -> ToKeyedWorkItem (7/32) (f00a31b722a31030f18d83ac613de21d) switched from RUNNING to FAILED.
AsynchronousException{java.lang.Exception: Could not materialize checkpoint 2 for operator Combine.perKey(Count) -> ParMultiDo(ToConcurrentStreamResult) -> ParMultiDo(Anonymous) -> ParMultiDo(ApplyShardingKey) -> ToKeyedWorkItem (7/32).}
at org.apache.flink.streaming.runtime.tasks.StreamTask$AsyncCheckpointRunnable.run(StreamTask.java:966)
at java.util.concurrent.Executors$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$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.Exception: Could not materialize checkpoint 2 for operator Combine.perKey(Count) -> ParMultiDo(ToConcurrentStreamResult) -> ParMultiDo(Anonymous) -> ParMultiDo(ApplyShardingKey) -> ToKeyedWorkItem (7/32).
... 6 more
Caused by: java.util.concurrent.ExecutionException: java.lang.NullPointerException
at java.util.concurrent.FutureTask.report(FutureTask.java:122)
at java.util.concurrent.FutureTask.get(FutureTask.java:192)
at org.apache.flink.util.FutureUtil.runIfNotDoneAndGet(FutureUtil.java:43)
at org.apache.flink.streaming.runtime.tasks.StreamTask$AsyncCheckpointRunnable.run(StreamTask.java:893)
... 5 more
Suppressed: java.lang.Exception: Could not properly cancel managed keyed state future.
at org.apache.flink.streaming.api.operators.OperatorSnapshotResult.cancel(OperatorSnapshotResult.java:90)
at org.apache.flink.streaming.runtime.tasks.StreamTask$AsyncCheckpointRunnable.cleanup(StreamTask.java:1018)
at org.apache.flink.streaming.runtime.tasks.StreamTask$AsyncCheckpointRunnable.run(StreamTask.java:957)
... 5 more
Caused by: java.util.concurrent.ExecutionException: java.lang.NullPointerException
at java.util.concurrent.FutureTask.report(FutureTask.java:122)
at java.util.concurrent.FutureTask.get(FutureTask.java:192)
at org.apache.flink.util.FutureUtil.runIfNotDoneAndGet(FutureUtil.java:43)
at org.apache.flink.runtime.state.StateUtil.discardStateFuture(StateUtil.java:85)
at org.apache.flink.streaming.api.operators.OperatorSnapshotResult.cancel(OperatorSnapshotResult.java:88)
... 7 more
Caused by: java.lang.NullPointerException
at java.io.DataOutputStream.writeUTF(DataOutputStream.java:347)
at java.io.DataOutputStream.writeUTF(DataOutputStream.java:323)
at org.apache.beam.runners.flink.translation.types.CoderTypeSerializer$CoderTypeSerializerConfigSnapshot.write(CoderTypeSerializer.java:189)
at org.apache.flink.api.common.typeutils.TypeSerializerSerializationUtil$TypeSerializerConfigSnapshotSerializationProxy.write(TypeSerializerSerializationUtil.java:413)
at org.apache.flink.api.common.typeutils.TypeSerializerSerializationUtil.writeSerializerConfigSnapshot(TypeSerializerSerializationUtil.java:229)
at org.apache.flink.api.common.typeutils.TypeSerializerSerializationUtil.writeSerializersAndConfigsWithResilience(TypeSerializerSerializationUtil.java:151)
at org.apache.flink.runtime.state.KeyedBackendStateMetaInfoSnapshotReaderWriters$KeyedBackendStateMetaInfoWriterV3.writeStateMetaInfo(KeyedBackendStateMetaInfoSnapshotReaderWriters.java:107)
at org.apache.flink.runtime.state.KeyedBackendSerializationProxy.write(KeyedBackendSerializationProxy.java:104)
at org.apache.flink.runtime.state.heap.HeapKeyedStateBackend$1.performOperation(HeapKeyedStateBackend.java:293)
at org.apache.flink.runtime.state.heap.HeapKeyedStateBackend$1.performOperation(HeapKeyedStateBackend.java:286)
at org.apache.flink.runtime.io.async.AbstractAsyncIOCallable.call(AbstractAsyncIOCallable.java:72)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at org.apache.flink.runtime.state.heap.HeapKeyedStateBackend.snapshot(HeapKeyedStateBackend.java:329)
at org.apache.flink.streaming.api.operators.AbstractStreamOperator.snapshotState(AbstractStreamOperator.java:397)
at org.apache.flink.streaming.runtime.tasks.StreamTask$CheckpointingOperation.checkpointStreamOperator(StreamTask.java:1157)
at org.apache.flink.streaming.runtime.tasks.StreamTask$CheckpointingOperation.executeCheckpointing(StreamTask.java:1089)
at org.apache.flink.streaming.runtime.tasks.StreamTask.checkpointState(StreamTask.java:653)
at org.apache.flink.streaming.runtime.tasks.StreamTask.performCheckpoint(StreamTask.java:589)
at org.apache.flink.streaming.runtime.tasks.StreamTask.triggerCheckpointOnBarrier(StreamTask.java:542)
at org.apache.flink.streaming.runtime.io.BarrierTracker.notifyCheckpoint(BarrierTracker.java:263)
at org.apache.flink.streaming.runtime.io.BarrierTracker.processBarrier(BarrierTracker.java:178)
at org.apache.flink.streaming.runtime.io.BarrierTracker.getNextNonBlocked(BarrierTracker.java:97)
at org.apache.flink.streaming.runtime.io.StreamInputProcessor.processInput(StreamInputProcessor.java:213)
at org.apache.flink.streaming.runtime.tasks.OneInputStreamTask.run(OneInputStreamTask.java:69)
at org.apache.flink.streaming.runtime.tasks.StreamTask.invoke(StreamTask.java:262)
at org.apache.flink.runtime.taskmanager.Task.run(Task.java:702)
... 1 more
{code}
From debugging locally I've narrowed it down to here
{code}
Caused by: java.lang.NullPointerException
at java.io.DataOutputStream.writeUTF(DataOutputStream.java:347)
at java.io.DataOutputStream.writeUTF(DataOutputStream.java:323)
at org.apache.beam.runners.flink.translation.types.CoderTypeSerializer$CoderTypeSerializerConfigSnapshot.write(CoderTypeSerializer.java:189)
at org.apache.flink.api.common.typeutils.TypeSerializerSerializationUtil$TypeSerializerConfigSnapshotSerializationProxy.write(TypeSerializerSerializationUtil.java:413)
{code}
Specifically in [CoderTypeSerializer.java#189|https://github.com/apache/beam/blob/609016d700c84800cf942482fb7cd2ddaa420b00/runners/flink/src/main/java/org/apache/beam/runners/flink/translation/types/CoderTypeSerializer.java#L189], when it calls {{DataOutputStream.write(String)}}, there is some logic in the {{write}} method that gets the string length. This is what is causing the NPE as the {{coderName}} field is null.
I think this stems from the [constructor|https://github.com/apache/beam/blob/609016d700c84800cf942482fb7cd2ddaa420b00/runners/flink/src/main/java/org/apache/beam/runners/flink/translation/types/CoderTypeSerializer.java#L164] which sets the {{coderName}} by calling {{.getClass().getCanonicalName();}} on the {{coder}} that is passed into the constructor
On debugging I've noticed this returns {{null}} when calling {{.getClass().getCanonicalName();}} on an instance of [Count$CountFn|https://github.com/apache/beam/blob/2040e2bd4203f81ea63966110e4eef3a1ff72393/sdks/java/core/src/main/java/org/apache/beam/sdk/transforms/Count.java#L134]
--
This message was sent by Atlassian JIRA
(v6.4.14#64029)