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Posted to issues@flink.apache.org by "Hang Ruan (Jira)" <ji...@apache.org> on 2021/08/18 12:42:00 UTC

[jira] [Comment Edited] (FLINK-23854) KafkaSink error when restart from the checkpoint with a lower parallelism by exactly-once guarantee

    [ https://issues.apache.org/jira/browse/FLINK-23854?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17401021#comment-17401021 ] 

Hang Ruan edited comment on FLINK-23854 at 8/18/21, 12:41 PM:
--------------------------------------------------------------

After adding log in StatefulSinkWriterStateHandler class, the distribution of the operator state changes as follow. 
||parallelism 4(before)||parallelism 2(after)||
|subTask0 -> state0
 subTask1 -> state1
 subTask2 -> state2
 subTask3 -> state3|subTask0 -> state0 & state1
 subTask1 - > state2 & state3|

Here are the log and the reult after changing to 2 parallelism.
||Add log in initializeState method of StatefulSinkWriterStateHandle||the log of subtask0||the log of subtask1||
|{code:java}
public List<WriterStateT> initializeState(StateInitializationContext context) throws Exception {
    final ListState<byte[]> rawState =
            context.getOperatorStateStore().getListState(WRITER_RAW_STATES_DESC);
    writerState =
            new SimpleVersionedListState<>(rawState, writerStateSimpleVersionedSerializer);
    final List<WriterStateT> writerStates = CollectionUtil.iterableToList(writerState.get());
    final List<WriterStateT> states = new ArrayList<>(writerStates);

    // add log
    for(WriterStateT stateT : states) {
        LOG.info("Stateful Sink Writer state handler:" + stateT.toString());
    }

    for (String previousSinkStateName : previousSinkStateNames) {
        ......
    }
    return states;
}
{code}|2021-08-18 20:02:04,214 INFO org.apache.flink.streaming.runtime.operators.sink.StatefulSinkWriterStateHandler [] - Stateful Sink Writer state handler:KafkaWriterState\{subtaskId=1, transactionalIdOffset=8, transactionalIdPrefix='tp-test-'}
 2021-08-18 20:02:04,214 INFO org.apache.flink.streaming.runtime.operators.sink.StatefulSinkWriterStateHandler [] - Stateful Sink Writer state handler:KafkaWriterState\{subtaskId=0, transactionalIdOffset=8, transactionalIdPrefix='tp-test-'}|2021-08-18 20:02:04,220 INFO org.apache.flink.streaming.runtime.operators.sink.StatefulSinkWriterStateHandler [] - Stateful Sink Writer state handler:KafkaWriterState\{subtaskId=2, transactionalIdOffset=8, transactionalIdPrefix='tp-test-'}
 2021-08-18 20:02:04,220 INFO org.apache.flink.streaming.runtime.operators.sink.StatefulSinkWriterStateHandler [] - Stateful Sink Writer state handler:KafkaWriterState\{subtaskId=3, transactionalIdOffset=8, transactionalIdPrefix='tp-test-'}|


was (Author: ruanhang1993):
After adding log in StatefulSinkWriterStateHandler class, the distribution of the operator state as follows.

 
||parallelism 4||parallelism 2||
|subTask0 -> state0
subTask1 -> state1
subTask2 -> state2
subTask3 -> state3|subTask0 -> state0 & state1
subTask1 - > state2 & state3|

 

Here are the log and the reult.
||Add log in initializeState method of StatefulSinkWriterStateHandle||the log of subtask0||the log of subtask1||
|{code:java}
public List<WriterStateT> initializeState(StateInitializationContext context) throws Exception {
    final ListState<byte[]> rawState =
            context.getOperatorStateStore().getListState(WRITER_RAW_STATES_DESC);
    writerState =
            new SimpleVersionedListState<>(rawState, writerStateSimpleVersionedSerializer);
    final List<WriterStateT> writerStates = CollectionUtil.iterableToList(writerState.get());
    final List<WriterStateT> states = new ArrayList<>(writerStates);

    // add log
    for(WriterStateT stateT : states) {
        LOG.info("Stateful Sink Writer state handler:" + stateT.toString());
    }

    for (String previousSinkStateName : previousSinkStateNames) {
        ......
    }
    return states;
}
{code}|2021-08-18 20:02:04,214 INFO org.apache.flink.streaming.runtime.operators.sink.StatefulSinkWriterStateHandler [] - Stateful Sink Writer state handler:KafkaWriterState\{subtaskId=1, transactionalIdOffset=8, transactionalIdPrefix='tp-test-'}
2021-08-18 20:02:04,214 INFO org.apache.flink.streaming.runtime.operators.sink.StatefulSinkWriterStateHandler [] - Stateful Sink Writer state handler:KafkaWriterState\{subtaskId=0, transactionalIdOffset=8, transactionalIdPrefix='tp-test-'}|2021-08-18 20:02:04,220 INFO org.apache.flink.streaming.runtime.operators.sink.StatefulSinkWriterStateHandler [] - Stateful Sink Writer state handler:KafkaWriterState\{subtaskId=2, transactionalIdOffset=8, transactionalIdPrefix='tp-test-'}
2021-08-18 20:02:04,220 INFO org.apache.flink.streaming.runtime.operators.sink.StatefulSinkWriterStateHandler [] - Stateful Sink Writer state handler:KafkaWriterState\{subtaskId=3, transactionalIdOffset=8, transactionalIdPrefix='tp-test-'}|

> KafkaSink error when restart from the checkpoint with a lower parallelism by exactly-once guarantee
> ---------------------------------------------------------------------------------------------------
>
>                 Key: FLINK-23854
>                 URL: https://issues.apache.org/jira/browse/FLINK-23854
>             Project: Flink
>          Issue Type: Bug
>          Components: Connectors / Kafka
>    Affects Versions: 1.14.0
>            Reporter: Hang Ruan
>            Priority: Blocker
>              Labels: release-testing
>
> The KafkaSink throws the exception when restarted with a lower parallelism and the exactly-once guarantee. The exception is like this.
> {code:java}
> // code placeholder
> java.lang.IllegalStateException: Internal error: It is expected that state from previous executions is distributed to the same subtask id.    at org.apache.flink.util.Preconditions.checkState(Preconditions.java:193)    at org.apache.flink.connector.kafka.sink.KafkaWriter.recoverAndInitializeState(KafkaWriter.java:178)    at org.apache.flink.connector.kafka.sink.KafkaWriter.<init>(KafkaWriter.java:130)    at org.apache.flink.connector.kafka.sink.KafkaSink.createWriter(KafkaSink.java:99)    at org.apache.flink.streaming.runtime.operators.sink.SinkOperator.initializeState(SinkOperator.java:134)    at org.apache.flink.streaming.api.operators.StreamOperatorStateHandler.initializeOperatorState(StreamOperatorStateHandler.java:118)    at org.apache.flink.streaming.api.operators.AbstractStreamOperator.initializeState(AbstractStreamOperator.java:286)    at org.apache.flink.streaming.runtime.tasks.RegularOperatorChain.initializeStateAndOpenOperators(RegularOperatorChain.java:109)    at org.apache.flink.streaming.runtime.tasks.StreamTask.restoreGates(StreamTask.java:690)    at org.apache.flink.streaming.runtime.tasks.StreamTaskActionExecutor$1.call(StreamTaskActionExecutor.java:55)    at org.apache.flink.streaming.runtime.tasks.StreamTask.executeRestore(StreamTask.java:666)    at org.apache.flink.streaming.runtime.tasks.StreamTask.runWithCleanUpOnFail(StreamTask.java:785)    at org.apache.flink.streaming.runtime.tasks.StreamTask.restore(StreamTask.java:638)    at org.apache.flink.runtime.taskmanager.Task.doRun(Task.java:766)    at org.apache.flink.runtime.taskmanager.Task.run(Task.java:572)    at java.lang.Thread.run(Thread.java:748)    Suppressed: java.lang.NullPointerException        at org.apache.flink.streaming.runtime.operators.sink.SinkOperator.close(SinkOperator.java:195)        at org.apache.flink.streaming.runtime.tasks.StreamOperatorWrapper.close(StreamOperatorWrapper.java:141)        at org.apache.flink.streaming.runtime.tasks.RegularOperatorChain.closeAllOperators(RegularOperatorChain.java:127)        at org.apache.flink.streaming.runtime.tasks.StreamTask.closeAllOperators(StreamTask.java:1028)        at org.apache.flink.streaming.runtime.tasks.StreamTask.runAndSuppressThrowable(StreamTask.java:1014)        at org.apache.flink.streaming.runtime.tasks.StreamTask.cleanUpInvoke(StreamTask.java:927)        at org.apache.flink.streaming.runtime.tasks.StreamTask.runWithCleanUpOnFail(StreamTask.java:797)        ... 4 more
> {code}
> I start the kafka cluster(kafka_2.13-2.8.0) and the flink cluster in my own mac. I change the parallelism from 4 to 2 and restart the job from some completed checkpoint. Then the error occurs. 
> And the cli command and the code are as follows.
> {code:java}
> // cli command
> ./bin/flink run -d -c com.test.KafkaExactlyOnceScaleDownTest -s /Users/test/checkpointDir/ExactlyOnceTest1/67105fcc1724e147fc6208af0dd90618/chk-1 /Users/test/project/self/target/test.jar
> {code}
> {code:java}
> public class KafkaExactlyOnceScaleDownTest { 
> public static void main(String[] args) throws Exception { 
>     final String kafkaSourceTopic = "flinkSourceTest"; 
>     final String kafkaSinkTopic = "flinkSinkExactlyTest1"; 
>     final String groupId = "ExactlyOnceTest1"; 
>     final String brokers = "localhost:9092"; 
>     final String ckDir = "file:///Users/test/checkpointDir/" + groupId; 
>     final StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment(); 
>     env.enableCheckpointing(60000); 
>     env.getCheckpointConfig().setCheckpointingMode(CheckpointingMode.EXACTLY_ONCE);        
> env.getCheckpointConfig().enableExternalizedCheckpoints(CheckpointConfig.ExternalizedCheckpointCleanup.RETAIN_ON_CANCELLATION);
>     env.getCheckpointConfig().setCheckpointStorage(ckDir); 
>     env.setParallelism(4); 
>     KafkaSource<String> source = KafkaSource.<String>builder() 
>      .setBootstrapServers(brokers) 
>      .setTopics(kafkaSourceTopic) 
>      .setGroupId(groupId) 
>      .setProperty(ConsumerConfig.AUTO_OFFSET_RESET_CONFIG, "earliest") 
>      .setValueOnlyDeserializer(new SimpleStringSchema()) 
>      .build(); 
>     DataStream<String> flintstones = env.fromSource(source, WatermarkStrategy.noWatermarks(), "Kafka Source"); 
>     DataStream<String> adults = flintstones.filter(s -> s != null && s.length() > 2); 
>     Properties props = new Properties(); 
>     props.setProperty("transaction.timeout.ms", "900000"); 
>     adults.sinkTo(KafkaSink.<String>builder() 
>     .setBootstrapServers(brokers) 
>     .setDeliverGuarantee(DeliveryGuarantee.EXACTLY_ONCE) 
>     .setTransactionalIdPrefix("tp-test-") 
>     .setKafkaProducerConfig(props) 
>     .setRecordSerializer(new SelfSerializationSchema(kafkaSinkTopic, new SimpleStringSchema())) 
>     .build()); 
>     env.execute("ScaleDownTest"); 
> } 
> static class SelfSerializationSchema implements KafkaRecordSerializationSchema<String> { private final SerializationSchema<String> valueSerialization; private String topic; SelfSerializationSchema(String topic, SerializationSchema<String> valueSerialization){ this.valueSerialization = valueSerialization; this.topic = topic; } @Override public void open(SerializationSchema.InitializationContext context, KafkaSinkContext sinkContext) throws Exception { KafkaRecordSerializationSchema.super.open(context, sinkContext); } @Override public ProducerRecord<byte[], byte[]> serialize(String s, KafkaSinkContext kafkaSinkContext, Long aLong) { final byte[] valueSerialized = valueSerialization.serialize(s); return new ProducerRecord<>(topic, valueSerialized); } } 
> }
> {code}



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