[KAFKA-8178] KafkaProducer#send(ProducerRecord,Callback) may block for up to 60 seconds

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Component/s: clients, producer
• Assignee: Unassigned
• Reporter: Sergei Egorov
• Created: 31/Mar/19 12:52
• Updated: 14/Apr/22 22:29

Description

Hello. I was running reactor-kafka with the BlockHound agent (you can see the progress here and even run it yourself) and it detected a very dangerous blocking call in KafkaProducer#send(ProducerRecord,Callback) which is supposed to be async:

java.lang.Error: Blocking call! java.lang.Object#wait
	at reactor.BlockHound$Builder.lambda$new$0(BlockHound.java:154)
	at reactor.BlockHound$Builder.lambda$install$8(BlockHound.java:254)
	at reactor.BlockHoundRuntime.checkBlocking(BlockHoundRuntime.java:43)
	at java.lang.Object.wait(Object.java)
	at org.apache.kafka.clients.Metadata.awaitUpdate(Metadata.java:181)
	at org.apache.kafka.clients.producer.KafkaProducer.waitOnMetadata(KafkaProducer.java:938)
	at org.apache.kafka.clients.producer.KafkaProducer.doSend(KafkaProducer.java:823)
	at org.apache.kafka.clients.producer.KafkaProducer.send(KafkaProducer.java:803)

it blocks for up to "maxBlockTimeMs" (60 seconds by default)

Issue Links

• is related to: KAFKA-3450 Producer blocks on send to topic that doesn't exist if auto create is disabled
• is related to: KAFKA-3539 KafkaProducer.send() may block even though it returns the Future