Calvin Liu created KAFKA-19212: ---------------------------------- Summary: Fix ElectionWasClean method bug when partition reassignment completes Key: KAFKA-19212 URL: https://issues.apache.org/jira/browse/KAFKA-19212 Project: Kafka Issue Type: Bug Reporter: Calvin Liu Assignee: Calvin Liu Fix For: 4.1.0
The current ElectionWasClean checks if the new leader is in the previous ISR. However, there is a corner case in the partition reassignment. The partition reassignment can change the partition replicas. If the new preferred leader (the first one in the new replicas) is the last one to join ISR, this preferred leader will be elected in the same partition change. For example: In the previous state, the partition is Leader: 0, Replicas (2,1,0), ISR (1,0), Adding(2), removing(0). Then replica 2 joins the ISR. The new partition would be like: Leader: 2, Replicas (2,1), ISR(1,2). The new leader 2 is not in the previous ISR (1,0) but it is still a clean election. -- This message was sent by Atlassian Jira (v8.20.10#820010)