[ https://issues.apache.org/jira/browse/KAFKA-14573?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Stephane Maarek updated KAFKA-14573: ------------------------------------ Description: Create a topic with 6 partitions (that's how the behavior is observed) ``` kafka-topics.sh --bootstrap-server localhost:9092 --topic test_topic --create --partitions 6 ``` Start a consumer ``` kafka-console-consumer --bootstrap-server localhost:9092 --topic test_topic --formatter kafka.tools.DefaultMessageFormatter --property print.timestamp=true --property print.key=true --property print.value=true --property print.partition=true --from-beginning ``` Start a producer using `RoundRobinPartitioner` ``` kafka-console-producer.sh --bootstrap-server localhost:9092 --producer-property partitioner.class=org.apache.kafka.clients.producer.RoundRobinPartitioner --topic test_topic ``` And you will see only 3 partitions get produced to (not 6) This doesn't happen with 3 partitions, 5, 7, 9 partitions (we get the expected behavior). But with 6.... it happens. Verified to be like this on my colleague's computer too. ``` CreateTime: 1672859052082 Partition: 5 null a CreateTime: 1672859053586 Partition: 1 null b CreateTime: 1672859054995 Partition: 3 null C CreateTime: 1672859056405 Partition: 5 null d CreateTime: 1672859057861 Partition: 1 null e CreateTime: 1672859059181 Partition: 3 null e ``` was: Create a topic with 6 partitions (that's how the behavior is observed) ``` kafka-topics.sh --bootstrap-server localhost:9092 --topic test_topic --create --partitions 6 ``` Start a consumer ``` kafka-console-consumer --bootstrap-server localhost:9092 --topic test_topic --formatter kafka.tools.DefaultMessageFormatter --property print.timestamp=true --property print.key=true --property print.value=true --property print.partition=true --from-beginning ``` Start a producer using `RoundRobinPartitioner` ``` kafka-console-producer.sh --bootstrap-server localhost:9092 --producer-property partitioner.class=org.apache.kafka.clients.producer.RoundRobinPartitioner --topic test_topic ``` And you will see only 3 partitions get produced to (not 6) This doesn't happen with 3 partitions, 5, 7, 9 partitions (we get the expected behavior). But with 6.... it happens. Verified to be like this on my colleague's computer too. !image-2023-01-04-20-15-43-039.png! > RoundRobinPartitioner doesn't work as expected with topic that has 6 > partitions > ------------------------------------------------------------------------------- > > Key: KAFKA-14573 > URL: https://issues.apache.org/jira/browse/KAFKA-14573 > Project: Kafka > Issue Type: Bug > Affects Versions: 3.3.1 > Reporter: Stephane Maarek > Priority: Major > Attachments: image-2023-01-04-20-15-43-039.png > > > Create a topic with 6 partitions (that's how the behavior is observed) > ``` > kafka-topics.sh --bootstrap-server localhost:9092 --topic test_topic --create > --partitions 6 > ``` > Start a consumer > ``` > kafka-console-consumer --bootstrap-server localhost:9092 --topic test_topic > --formatter kafka.tools.DefaultMessageFormatter --property > print.timestamp=true --property print.key=true --property print.value=true > --property print.partition=true --from-beginning > ``` > Start a producer using `RoundRobinPartitioner` > ``` > kafka-console-producer.sh --bootstrap-server localhost:9092 > --producer-property > partitioner.class=org.apache.kafka.clients.producer.RoundRobinPartitioner > --topic test_topic > ``` > And you will see only 3 partitions get produced to (not 6) > This doesn't happen with 3 partitions, 5, 7, 9 partitions (we get the > expected behavior). > But with 6.... it happens. > Verified to be like this on my colleague's computer too. > ``` > CreateTime: 1672859052082 Partition: 5 null a > CreateTime: 1672859053586 Partition: 1 null b > CreateTime: 1672859054995 Partition: 3 null C > CreateTime: 1672859056405 Partition: 5 null d > CreateTime: 1672859057861 Partition: 1 null e > CreateTime: 1672859059181 Partition: 3 null e > ``` -- This message was sent by Atlassian Jira (v8.20.10#820010)