xiaotong.wang created KAFKA-10254: ------------------------------------- Summary: 100% cpu usage by kafkaConsumer poll , when broker can‘t be connect Key: KAFKA-10254 URL: https://issues.apache.org/jira/browse/KAFKA-10254 Project: Kafka Issue Type: Bug Components: clients Affects Versions: 2.5.0 Reporter: xiaotong.wang Attachments: image-2020-07-09-19-24-20-604.png
steps 1、start kafka broker 2、start kafka consumer and subscribe some topic with some kafkaConsumer instance and call kafkaConsumer.*poll(Duration.ofMillis(pollTimeout))* and set auto.commit.enabled=false 3、iptables to disable kafka broker ip in client vm or shutdown kafka brokers 4、cpu go to 100% *why?* left Vserison :2.3.1 right Version:2.5.0 for 2.3.1 kafkaConsumer when kafka brokers go down,updateAssignmentMetadataIfNeeded will block x ms and return empty records , !image-2020-07-09-19-24-20-604.png! for 2.5.0 private Map<TopicPartition, List<ConsumerRecord<K, V>>> pollForFetches(Timer timer) { *long pollTimeout = coordinator == null ? timer.remainingMs() :* *Math.min(coordinator.timeToNextPoll(timer.currentTimeMs()), timer.remainingMs());* i check the source of kafka client ,poll timeout will be change to 0 ms ,when heartbeat timeout ,so it will call poll without any block ,this will cause cpu go to 100% -- This message was sent by Atlassian Jira (v8.3.4#803005)