Aljoscha Krettek created FLINK-6515: ---------------------------------------
Summary: KafkaConsumer checkpointing fails because of ClassLoader issues Key: FLINK-6515 URL: https://issues.apache.org/jira/browse/FLINK-6515 Project: Flink Issue Type: Bug Components: Kafka Connector Affects Versions: 1.3.0 Reporter: Aljoscha Krettek Priority: Blocker Fix For: 1.3.0 A job with Kafka and checkpointing enabled fails with: {code} java.lang.Exception: Error while triggering checkpoint 1 for Source: Custom Source -> Map -> Sink: Unnamed (1/1) at org.apache.flink.runtime.taskmanager.Task$3.run(Task.java:1195) at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) at java.util.concurrent.FutureTask.run(FutureTask.java:266) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) at java.lang.Thread.run(Thread.java:745) Caused by: java.lang.Exception: Could not perform checkpoint 1 for operator Source: Custom Source -> Map -> Sink: Unnamed (1/1). at org.apache.flink.streaming.runtime.tasks.StreamTask.triggerCheckpoint(StreamTask.java:526) at org.apache.flink.streaming.runtime.tasks.SourceStreamTask.triggerCheckpoint(SourceStreamTask.java:112) at org.apache.flink.runtime.taskmanager.Task$3.run(Task.java:1184) ... 5 more Caused by: java.lang.Exception: Could not complete snapshot 1 for operator Source: Custom Source -> Map -> Sink: Unnamed (1/1). at org.apache.flink.streaming.api.operators.AbstractStreamOperator.snapshotState(AbstractStreamOperator.java:407) at org.apache.flink.streaming.runtime.tasks.StreamTask$CheckpointingOperation.checkpointStreamOperator(StreamTask.java:1157) at org.apache.flink.streaming.runtime.tasks.StreamTask$CheckpointingOperation.executeCheckpointing(StreamTask.java:1089) at org.apache.flink.streaming.runtime.tasks.StreamTask.checkpointState(StreamTask.java:653) at org.apache.flink.streaming.runtime.tasks.StreamTask.performCheckpoint(StreamTask.java:589) at org.apache.flink.streaming.runtime.tasks.StreamTask.triggerCheckpoint(StreamTask.java:520) ... 7 more Caused by: java.lang.RuntimeException: Could not copy instance of (KafkaTopicPartition{topic='test-input', partition=0},-1). at org.apache.flink.runtime.state.JavaSerializer.copy(JavaSerializer.java:54) at org.apache.flink.runtime.state.JavaSerializer.copy(JavaSerializer.java:32) at org.apache.flink.runtime.state.ArrayListSerializer.copy(ArrayListSerializer.java:71) at org.apache.flink.runtime.state.DefaultOperatorStateBackend$PartitionableListState.<init>(DefaultOperatorStateBackend.java:368) at org.apache.flink.runtime.state.DefaultOperatorStateBackend$PartitionableListState.deepCopy(DefaultOperatorStateBackend.java:380) at org.apache.flink.runtime.state.DefaultOperatorStateBackend.snapshot(DefaultOperatorStateBackend.java:191) at org.apache.flink.streaming.api.operators.AbstractStreamOperator.snapshotState(AbstractStreamOperator.java:392) ... 12 more Caused by: java.lang.ClassNotFoundException: org.apache.flink.streaming.connectors.kafka.internals.KafkaTopicPartition at java.net.URLClassLoader.findClass(URLClassLoader.java:381) at java.lang.ClassLoader.loadClass(ClassLoader.java:424) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331) at java.lang.ClassLoader.loadClass(ClassLoader.java:357) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:348) at org.apache.flink.util.InstantiationUtil$ClassLoaderObjectInputStream.resolveClass(InstantiationUtil.java:64) at java.io.ObjectInputStream.readNonProxyDesc(ObjectInputStream.java:1620) at java.io.ObjectInputStream.readClassDesc(ObjectInputStream.java:1521) at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1781) at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1353) at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:2018) at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1942) at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1808) at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1353) at java.io.ObjectInputStream.readObject(ObjectInputStream.java:373) at org.apache.flink.util.InstantiationUtil.deserializeObject(InstantiationUtil.java:290) at org.apache.flink.util.InstantiationUtil.clone(InstantiationUtil.java:371) at org.apache.flink.util.InstantiationUtil.clone(InstantiationUtil.java:349) at org.apache.flink.runtime.state.JavaSerializer.copy(JavaSerializer.java:52) ... 18 more {code} The problem seems to be {{TypeSerializer.copy()}}, which uses the wrong ClassLoader. Until recently this was not used but recent changes around asynchronous checkpointing of operator state require deep copies of the operator {{ListState}} and thus call this method. -- This message was sent by Atlassian JIRA (v6.3.15#6346)