Sry for wrong post.
> This can probably be confirmed by looking at the exception stack trace.
> Can you post a full copy of that?
I missed the history jobs, but I think u r right.
When I debug the program to find reason, came into these code snippet.
```
TypeSerializerSchemaCompatibility<T> result =
previousSerializerSnapshot.resolveSchemaCompatibility(registeredSerializer);
if (result.isIncompatible()) {
invalidateCurrentSchemaSerializerAccess();
}
```
I remember one is
`org.apache.flink.api.common.typeutils.base.LongSerializer$LongSerializerSnapshot`,
another is just `Kryo`.
> Can you open a JIRA for this? I think it'll be a reasonable extension to
> the API.
I'll do that, 3q.
> I'm not sure what you mean here. Where is this keyBy happening? In the
> Scala DataStream job, or the State Processor API?
In the Scala DataStream job, same with the examples of link-1 in the origial
post。
I change keyBy(_._1) to keyBy(0), then the program will throw an exception.
The full copy from job Exceptions:
```
java.io.IOException: Failed to restore state backend
at
org.apache.flink.state.api.input.KeyedStateInputFormat.getStreamOperatorStateContext(KeyedStateInputFormat.java:231)
at
org.apache.flink.state.api.input.KeyedStateInputFormat.open(KeyedStateInputFormat.java:177)
at
org.apache.flink.state.api.input.KeyedStateInputFormat.open(KeyedStateInputFormat.java:79)
at
org.apache.flink.runtime.operators.DataSourceTask.invoke(DataSourceTask.java:173)
at org.apache.flink.runtime.taskmanager.Task.doRun(Task.java:705)
at org.apache.flink.runtime.taskmanager.Task.run(Task.java:530)
at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.Exception: Exception while creating
StreamOperatorStateContext.
at
org.apache.flink.streaming.api.operators.StreamTaskStateInitializerImpl.streamOperatorStateContext(StreamTaskStateInitializerImpl.java:195)
at
org.apache.flink.state.api.input.KeyedStateInputFormat.getStreamOperatorStateContext(KeyedStateInputFormat.java:223)
... 6 more
Caused by: org.apache.flink.util.FlinkException: Could not restore keyed
state backend for
8f89af64b0cf95ff20b8dda264c66f81_8f89af64b0cf95ff20b8dda264c66f81_(1/1) from
any of the 1 provided 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)
... 7 more
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:116)
at
org.apache.flink.runtime.state.memory.MemoryStateBackend.createKeyedStateBackend(MemoryStateBackend.java:347)
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)
... 9 more
Caused by: org.apache.flink.util.StateMigrationException: The new key
serializer must be compatible.
at
org.apache.flink.runtime.state.heap.HeapRestoreOperation.restore(HeapRestoreOperation.java:142)
at
org.apache.flink.runtime.state.heap.HeapKeyedStateBackendBuilder.build(HeapKeyedStateBackendBuilder.java:114)
... 13 more
```
Maybe it's explainable with 「inferred and serialized as their Java
counterparts」, not sure, I am a triple beginner with Java & Scala & Flink.
Thanks a lot.
--
Sent from: http://apache-flink-user-mailing-list-archive.2336050.n4.nabble.com/
