Kafka streams联接中的RecordTooLargeException

Question

我有一个KStream x KStream连接，它正在中断，但有以下例外。

Exception in thread “my-clicks-and-recs-join-streams-4c903fb1-5938-4919-9c56-2c8043b86986-StreamThread-1" org.apache.kafka.streams.errors.StreamsException: Exception caught in process. taskId=0_15, processor=KSTREAM-SOURCE-0000000001, topic=my_outgoing_recs_prod, partition=15, offset=9248896
    at org.apache.kafka.streams.processor.internals.StreamTask.process(StreamTask.java:203)
    at org.apache.kafka.streams.processor.internals.StreamThread.processAndPunctuate(StreamThread.java:679)
    at org.apache.kafka.streams.processor.internals.StreamThread.runLoop(StreamThread.java:557)
    at org.apache.kafka.streams.processor.internals.StreamThread.run(StreamThread.java:527)
Caused by: org.apache.kafka.streams.errors.StreamsException: task [0_15] exception caught when producing
    at org.apache.kafka.streams.processor.internals.RecordCollectorImpl.checkForException(RecordCollectorImpl.java:136)
    at org.apache.kafka.streams.processor.internals.RecordCollectorImpl.send(RecordCollectorImpl.java:87)
    at org.apache.kafka.streams.state.internals.StoreChangeLogger.logChange(StoreChangeLogger.java:59)
    at org.apache.kafka.streams.state.internals.ChangeLoggingSegmentedBytesStore.put(ChangeLoggingSegmentedBytesStore.java:59)
    at org.apache.kafka.streams.state.internals.MeteredSegmentedBytesStore.put(MeteredSegmentedBytesStore.java:105)
    at org.apache.kafka.streams.state.internals.RocksDBWindowStore.put(RocksDBWindowStore.java:107)
    at org.apache.kafka.streams.state.internals.RocksDBWindowStore.put(RocksDBWindowStore.java:100)
    at org.apache.kafka.streams.kstream.internals.KStreamJoinWindow$KStreamJoinWindowProcessor.process(KStreamJoinWindow.java:64)
    at org.apache.kafka.streams.processor.internals.ProcessorNode$1.run(ProcessorNode.java:47)
    at org.apache.kafka.streams.processor.internals.StreamsMetricsImpl.measureLatencyNs(StreamsMetricsImpl.java:187)
    at org.apache.kafka.streams.processor.internals.ProcessorNode.process(ProcessorNode.java:133)
    at org.apache.kafka.streams.processor.internals.ProcessorContextImpl.forward(ProcessorContextImpl.java:82)
    at org.apache.kafka.streams.processor.internals.SourceNode.process(SourceNode.java:80)
    at org.apache.kafka.streams.processor.internals.StreamTask.process(StreamTask.java:189)
    ... 3 more
Caused by: org.apache.kafka.common.errors.RecordTooLargeException: The request included a message larger than the max message size the server will accept.

尽管如此，我尝试将属性设置为config.put（“max.request.size”，“31457280”）；，即30MB。我不希望推荐记录超过这个限制。但是，代码还是崩溃了。

我不能更改Kafka集群中的配置，但如果需要，我可以更改Kafka中相关主题的属性。

有人能建议我还能试试什么吗？

如果什么都不起作用，我愿意忽略这样的超大信息。但是，我不知道处理这个RecordToolargeException的方法。

执行连接的代码如下所示。

Properties config = new Properties();
config.put(StreamsConfig.APPLICATION_ID_CONFIG, JOINER_ID + "-" + System.getenv("HOSTNAME"));
config.put(StreamsConfig.BOOTSTRAP_SERVERS_CONFIG, booststrapList);
config.put(StreamsConfig.DEFAULT_KEY_SERDE_CLASS_CONFIG, Serdes.String().getClass().getName());
config.put(StreamsConfig.DEFAULT_VALUE_SERDE_CLASS_CONFIG, Serdes.ByteArray().getClass().getName());
config.put("max.request.size", "314572800");
config.put("message.max.bytes", "314572800");
config.put("max.message.bytes", "314572800");


KStreamBuilder builder = new KStreamBuilder();

KStream<String, byte[]> clicksStream = builder.stream(TopologyBuilder.AutoOffsetReset.LATEST, Serdes.String(), Serdes.ByteArray(), clicksTopic);
KStream<String, byte[]> recsStream = builder.stream(TopologyBuilder.AutoOffsetReset.LATEST, Serdes.String(), Serdes.ByteArray(), recsTopic);

KStream<String, ClickRec> join = clicksStream.join(
        recsStream,
        (click, recs) -> new ClickRec(click, recs),
        JoinWindows.of(windowMillis).until(3*windowMillis));

join.to(Serdes.String(), JoinSerdes.CLICK_SERDE, jointTopic);

KafkaStreams streams = new KafkaStreams(builder, config);
streams.cleanUp();
streams.start();

clickrec是连接的对象（它远小于recomment对象，我不希望它大于几KBs）。

Answer 1

在不同级别上有多个配置：

1. 您有一个代理设置message.max.bytes（默认值为1000012)（参见http://kafka.apache.org/documentation/#brokerconfigs)
2. 有一个主题级配置max.message.bytes（默认值为1000012)（cf http://kafka.apache.org/documentation/#topicconfigs)
3. 生产者具有max.request.size（默认值为1048576)（参见http://kafka.apache.org/documentation/#producerconfigs)

堆栈跟踪指示您需要在代理或主题级别更改设置：

为什么首先需要这个：

当您执行KStream-KStream联接时，join运算符建立状态（它必须缓冲两个流中的记录，以便计算联接）。状态默认由Kafaka主题支持--本地状态基本上是一个缓存，而Kafaka主题是真理的来源。因此，您的所有记录都将写入Kafka Streams自动创建的“变更日志主题”。