[KAFKA-8171] callback needs to be null when addStopReplicaRequestForBrokers when replica state transits to offline

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Component/s: controller
• Assignee: Unassigned
• Reporter: kehu
• Created: 28/Mar/19 17:17
• Updated: 11/May/19 06:49
• Resolved: 11/May/19 06:49

Description

Problem: 

In ControllerChannelManager.sendRequestsToBrokers, for STOP_REPLICA requests, it will try to group the requests based on deletePartition flag and callback:

val (replicasToGroup, replicasToNotGroup) = replicaInfoList.partition(r => !r.deletePartition && r.callback == null)

When both conditions meet, controller is expected to send only one request to destination broker. However, when adding the requests in ReplicaStateMachine, it's putting in non-null callback (,)=>(). Therefore, replicasToGroup is always empty and controller will always first sends an empty request followed by #partitions requests.

 

Fix: set the callback to null in addStopReplicaRequestForBrokers when replica state transits to offline. PR has been created: https://github.com/apache/kafka/pull/6515

Issue Links

• links to: GitHub Pull Request #6515