Hi Georgi, I don't think it's a bug in Flink. It sounds like some problem with dependencies or jars in your job. Can you explain a bit more what do you mean by:
> that some of them are constantly restarting with the following exception. After restart, everything is working as expected constantly restarting, but after a restart everything is working? Best, Piotrek wt., 25 maj 2021 o 16:12 Georgi Stoyanov <gstoya...@live.com> napisał(a): > Hi all, > > > We have running several Flink jobs on k8s with flink 1.11.3 and recently > we notice that some of them are constantly restarting with the following > exception. After restart, everything is working as expected. > Could this be a bug? > 2021-05-25 17:04:42 > org.apache.flink.streaming.runtime.tasks.StreamTaskException: Cannot > instantiate user function. > at > org.apache.flink.streaming.api.graph.StreamConfig.getStreamOperatorFactory(StreamConfig.java:275) > at > org.apache.flink.streaming.runtime.tasks.OperatorChain.<init>(OperatorChain.java:126) > at > org.apache.flink.streaming.runtime.tasks.StreamTask.beforeInvoke(StreamTask.java:459) > at > org.apache.flink.streaming.runtime.tasks.StreamTask.invoke(StreamTask.java:526) > at org.apache.flink.runtime.taskmanager.Task.doRun(Task.java:721) > at org.apache.flink.runtime.taskmanager.Task.run(Task.java:546) > at java.lang.Thread.run(Thread.java:748) > Caused by: java.io.IOException: unexpected exception type > at > java.io.ObjectStreamClass.throwMiscException(ObjectStreamClass.java:1750) > at > java.io.ObjectStreamClass.invokeReadResolve(ObjectStreamClass.java:1280) > at > java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:2196) > at > java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1667) > at > java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:2405) > at > java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:2329) > at > java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:2187) > at > java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1667) > at > java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:2405) > at > java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:2329) > at > java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:2187) > at > java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1667) > at java.io.ObjectInputStream.readObject(ObjectInputStream.java:503) > at java.io.ObjectInputStream.readObject(ObjectInputStream.java:461) > at > org.apache.flink.util.InstantiationUtil.deserializeObject(InstantiationUtil.java:576) > at > org.apache.flink.util.InstantiationUtil.deserializeObject(InstantiationUtil.java:562) > at > org.apache.flink.util.InstantiationUtil.deserializeObject(InstantiationUtil.java:550) > at > org.apache.flink.util.InstantiationUtil.readObjectFromConfig(InstantiationUtil.java:511) > at > org.apache.flink.streaming.api.graph.StreamConfig.getStreamOperatorFactory(StreamConfig.java:260) > ... 6 more > Caused by: java.lang.reflect.InvocationTargetException > at sun.reflect.GeneratedMethodAccessor282.invoke(Unknown Source) > at > sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) > at java.lang.reflect.Method.invoke(Method.java:498) > at > java.lang.invoke.SerializedLambda.readResolve(SerializedLambda.java:230) > at sun.reflect.GeneratedMethodAccessor281.invoke(Unknown Source) > at > sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) > at java.lang.reflect.Method.invoke(Method.java:498) > at > java.io.ObjectStreamClass.invokeReadResolve(ObjectStreamClass.java:1274) > ... 23 more > Caused by: java.lang.NoClassDefFoundError: Could not initialize > com.my.organization.MyPerfectlyWorkingJob > ... 31 more > >
