[jira] [Created] (KAFKA-1503) all partitions are using same broker as their leader after broker is down

["Jianwen Wang (JIRA)" <ji...@apache.org>]

Jianwen Wang created KAFKA-1503:
-----------------------------------

             Summary: all partitions are using same broker as their leader after broker is down
                 Key: KAFKA-1503
                 URL: https://issues.apache.org/jira/browse/KAFKA-1503
             Project: Kafka
          Issue Type: Bug
          Components: controller
    Affects Versions: 0.8.1.1, 0.8.0
         Environment: 0.8.1.1 
            Reporter: Jianwen Wang
            Assignee: Neha Narkhede


The current leader selection always pick the first live broker in ISR when the current leader broker is down. Since the list of liveBrokerInIsr is not evenly distributed. As time goes on, all the partitions will use only one broker as its leader. 

I figured out a fix which is to use the first live broker in replica list which is also in ISR list. Since the liveAssignedReplicas is evenly distributed across brokers, all the partitions will be evenly distributed in the live brokers in ISR.
The fix is:
kafka-0.8.1.1-src/core/src/main/scala/kafka/controller/PartitionLeaderSelector.scala


71	71
           case false =>
72	 
-            val newLeader = liveBrokersInIsr.head
 	72
+            val liveReplicasInIsr = liveAssignedReplicas.filter(r => liveBrokersInIsr.contains(r))
 	73
+            val newLeader = liveReplicasInIsr.head



--
This message was sent by Atlassian JIRA
(v6.2#6252)