[KAFKA-13227] Cancel pending AlterIsr requests after receiving LeaderAndIsr

• Type: Improvement
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Assignee: Christo Lolov
• Reporter: Jason Gustafson
• Created: 25/Aug/21 18:40
• Updated: 17/Nov/21 20:28

Description

Currently we do not cancel pending AlterIsr requests after the state has been updated through a LeaderAndIsr request received from the controller. This leads to log messages such as this

[2021-08-23 18:12:47,317] WARN [Partition __transaction_state-32 broker=3] Failed to enqueue ISR change state LeaderAndIsr(leader=3, leaderEpoch=3, isUncleanLeader=false, isr=List(3, 1), zkVersion=3) for partition __transaction_state-32 (kafka.cluster.Partition)

I think the only complication here is protecting against the AlterIsr callback which is executed asynchronously. To address this, we can move the `zkVersion` field into `IsrState`. When the callback is invoked, we can the existing state against the response state to decide whether to apply the change.

Issue Links

• is related to: KAFKA-12686 Race condition in AlterIsr response handling