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Takuya Fukudome commented on HDFS-8827: --------------------------------------- Thanks for the clarifications and fix, [~walter.k.su]! > Erasure Coding: When namenode processes over replicated striped block, NPE > will be occur in ReplicationMonitor > -------------------------------------------------------------------------------------------------------------- > > Key: HDFS-8827 > URL: https://issues.apache.org/jira/browse/HDFS-8827 > Project: Hadoop HDFS > Issue Type: Sub-task > Reporter: Takuya Fukudome > Assignee: Takuya Fukudome > Attachments: HDFS-8827-HDFS-7285.04.patch, HDFS-8827.1.patch, > HDFS-8827.2.patch, HDFS-8827.3.patch, processing-over-replica-npe.log > > > In our test cluster, when namenode processed over replicated striped blocks, > null pointer exception(NPE) occurred. This happened under below situation: 1) > some datanodes shutdown. 2) namenode recovers block group which lost internal > blocks. 3) restart the stopped datanodes. 4) namenode processes over > replicated striped blocks. 5) NPE occurs > I think BlockPlacementPolicyDefault#chooseReplicaToDelete will return null in > this situation which causes this NPE problem. -- This message was sent by Atlassian JIRA (v6.3.4#6332)