Siddharth Anand created KAFKA-14757: ---------------------------------------
Summary: Kafka Cooperative Sticky Assignor results in significant duplicate consumption Key: KAFKA-14757 URL: https://issues.apache.org/jira/browse/KAFKA-14757 Project: Kafka Issue Type: Bug Components: consumer Affects Versions: 3.1.1 Environment: AWS MSK (broker) and Spring Kafka (2.8.7) for use in Spring Boot consumers. Reporter: Siddharth Anand Details may be found within the linked document: [Kafka Cooperative Sticky Assignor Issue : Duplicate Consumption | [https://docs.google.com/document/d/1E7qAwGOpF8jo_YhF4NwUx9CXxUGJmT8OhHEqIg7-GfI/edit?usp=sharing]] In a nutshell, we noticed that the Cooperative Sticky Assignor resulted in significant duplicate message consumption. During last year's F1 Grand Prix events and World Cup soccer events, our company's Kafka-based platform received live-traffic. This live traffic, coupled with autoscaled consumers resulted in as much as 70% duplicate message consumption at the Kafka consumers. In December 2022, we ran a synthetic load test to confirm that duplicate message consumption occurs during consumer scale out/in and Kafka partition rebalancing when using the Cooperative Sticky Assignor. This issue does not occur when using the Range Assignor. -- This message was sent by Atlassian Jira (v8.20.10#820010)