[ https://issues.apache.org/jira/browse/FLINK-13159?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Robert Metzger updated FLINK-13159: ----------------------------------- Component/s: API / Type Serialization System > java.lang.ClassNotFoundException when restore job > ------------------------------------------------- > > Key: FLINK-13159 > URL: https://issues.apache.org/jira/browse/FLINK-13159 > Project: Flink > Issue Type: Bug > Components: API / Type Serialization System > Reporter: kring > Priority: Critical > > {code:java} > java.lang.Exception: Exception while creating StreamOperatorStateContext. > at > org.apache.flink.streaming.api.operators.StreamTaskStateInitializerImpl.streamOperatorStateContext(StreamTaskStateInitializerImpl.java:195) > at > org.apache.flink.streaming.api.operators.AbstractStreamOperator.initializeState(AbstractStreamOperator.java:250) > at > org.apache.flink.streaming.runtime.tasks.StreamTask.initializeState(StreamTask.java:738) > at > org.apache.flink.streaming.runtime.tasks.StreamTask.invoke(StreamTask.java:289) > at org.apache.flink.runtime.taskmanager.Task.run(Task.java:711) > at java.lang.Thread.run(Thread.java:748) > Caused by: org.apache.flink.util.FlinkException: Could not restore keyed > state backend for WindowOperator_b398b3dd4c544ddf2d47a0cc47d332f4_(1/6) from > any of the 1 prov > ided restore options. > at > org.apache.flink.streaming.api.operators.BackendRestorerProcedure.createAndRestore(BackendRestorerProcedure.java:135) > at > org.apache.flink.streaming.api.operators.StreamTaskStateInitializerImpl.keyedStatedBackend(StreamTaskStateInitializerImpl.java:307) > at > org.apache.flink.streaming.api.operators.StreamTaskStateInitializerImpl.streamOperatorStateContext(StreamTaskStateInitializerImpl.java:135) > ... 5 common frames omitted > Caused by: org.apache.flink.runtime.state.BackendBuildingException: Failed > when trying to restore heap backend > at > org.apache.flink.runtime.state.heap.HeapKeyedStateBackendBuilder.build(HeapKeyedStateBackendBuilder.java:130) > at > org.apache.flink.runtime.state.filesystem.FsStateBackend.createKeyedStateBackend(FsStateBackend.java:489) > at > org.apache.flink.streaming.api.operators.StreamTaskStateInitializerImpl.lambda$keyedStatedBackend$1(StreamTaskStateInitializerImpl.java:291) > at > org.apache.flink.streaming.api.operators.BackendRestorerProcedure.attemptCreateAndRestore(BackendRestorerProcedure.java:142) > at > org.apache.flink.streaming.api.operators.BackendRestorerProcedure.createAndRestore(BackendRestorerProcedure.java:121) > ... 7 common frames omitted > Caused by: java.lang.RuntimeException: Cannot instantiate class. > at > org.apache.flink.api.java.typeutils.runtime.PojoSerializer.deserialize(PojoSerializer.java:384) > at > org.apache.flink.runtime.state.heap.StateTableByKeyGroupReaders.lambda$createV2PlusReader$0(StateTableByKeyGroupReaders.java:74) > at > org.apache.flink.runtime.state.KeyGroupPartitioner$PartitioningResultKeyGroupReader.readMappingsInKeyGroup(KeyGroupPartitioner.java:297) > at > org.apache.flink.runtime.state.heap.HeapRestoreOperation.readKeyGroupStateData(HeapRestoreOperation.java:290) > at > org.apache.flink.runtime.state.heap.HeapRestoreOperation.readStateHandleStateData(HeapRestoreOperation.java:251) > at > org.apache.flink.runtime.state.heap.HeapRestoreOperation.restore(HeapRestoreOperation.java:153) > at > org.apache.flink.runtime.state.heap.HeapKeyedStateBackendBuilder.build(HeapKeyedStateBackendBuilder.java:127) > ... 11 common frames omitted > Caused by: java.lang.ClassNotFoundException: xxx > at java.lang.Class.forName0(Native Method) > at java.lang.Class.forName(Class.java:348) > at > org.apache.flink.api.java.typeutils.runtime.PojoSerializer.deserialize(PojoSerializer.java:382) > ... 17 common frames omitted > {code} > A strange problem with Flink is that after a task has been running properly > for a period of time, if any exception (such as ask timeout or ES request > timeout) is thrown, the task restart will report the above error (xxx is a > business model), and ten subsequent retries will not succeed, but the task > will be resubmitted. Then it can run normally. In addition, there are three > other tasks running at the same time, none of which has the problem. > My flink version is 1.8.0. -- This message was sent by Atlassian JIRA (v7.6.3#76005)