Yiquan Zhou created KAFKA-4348: ---------------------------------- Summary: On Mac OS, KafkaConsumer.poll returns 0 when there are still messages on Kafka server Key: KAFKA-4348 URL: https://issues.apache.org/jira/browse/KAFKA-4348 Project: Kafka Issue Type: Bug Components: consumer Affects Versions: 0.10.0.1, 0.9.0.1, 0.9.0.0 Environment: Max OS X EI Capitan, Java 1.8.0_77 Reporter: Yiquan Zhou
Steps to reproduce: 1. start the zookeeper and kafka server using the default properties from the distribution: $ bin/zookeeper-server-start.sh config/zookeeper.properties $ bin/kafka-server-start.sh config/server.properties 2. create a Kafka consumer using the Java API KafkaConsumer.poll(long timeout). It polls the records from the server every second (timeout set to 1000) and prints the number of records polled. The code can be found here: https://gist.github.com/yiquanzhou/a94569a2c4ec8992444c83f3c393f596 3. use bin/kafka-verifiable-producer.sh to generate some messages: $ bin/kafka-verifiable-producer.sh --topic connect-test --max-messages 200000 --broker-list localhost:9092 wait until all 200k messages are generated and sent to the server. 4. Run the consumer Java code. In the output console of the consumer, we can see that the consumer starts to poll some records, then it polls 0 records for several seconds before polling some more. like this: polled 27160 records polled 0 records polled 0 records polled 0 records polled 0 records polled 0 records polled 26886 records polled 26886 records polled 0 records polled 0 records polled 0 records polled 0 records polled 0 records polled 26701 records polled 26214 records The impact of this bug is that it slows down the consumption of messages a lot. And if an eventListener is attached to the idle event, it could be triggered even if there are still messages on the server. It is only reproducible on Mac OS X but neither on Linux nor Windows. -- This message was sent by Atlassian JIRA (v6.3.4#6332)