ConfX created HDFS-17109:
----------------------------

             Summary: Null Pointer Exception when running TestBlockManager
                 Key: HDFS-17109
                 URL: https://issues.apache.org/jira/browse/HDFS-17109
             Project: Hadoop HDFS
          Issue Type: Bug
            Reporter: ConfX
         Attachments: reproduce.sh

h2. What happened

After setting {{{}dfs.namenode.redundancy.considerLoadByStorageType=true{}}}, 
running test 
{{org.apache.hadoop.hdfs.server.blockmanagement.TestBlockManager#testOneOfTwoRacksDecommissioned}}
 results in a {{{}NullPointerException{}}}.
h2. Where's the bug

In the class {{{}BlockPlacementPolicyDefault{}}}:
{noformat}
    for (StorageType s : storageTypes) {
      StorageTypeStats storageTypeStats = storageStats.get(s);
      numNodes += storageTypeStats.getNodesInService();
      numXceiver += storageTypeStats.getNodesInServiceXceiverCount();
    }{noformat}
However, the class does not check if the storageTypeStats is null, causing the 
NPE.
h2. How to reproduce
 # Set {{dfs.namenode.redundancy.considerLoadByStorageType=true}}
 # Run 
{{org.apache.hadoop.hdfs.server.blockmanagement.TestBlockManager#testOneOfTwoRacksDecommissioned}}
and the following exception should be observed:
{noformat}
java.lang.NullPointerException
    at 
org.apache.hadoop.hdfs.server.blockmanagement.BlockPlacementPolicyDefault.getInServiceXceiverAverageByStorageType(BlockPlacementPolicyDefault.java:1044)
    at 
org.apache.hadoop.hdfs.server.blockmanagement.BlockPlacementPolicyDefault.getInServiceXceiverAverage(BlockPlacementPolicyDefault.java:1023)
    at 
org.apache.hadoop.hdfs.server.blockmanagement.BlockPlacementPolicyDefault.excludeNodeByLoad(BlockPlacementPolicyDefault.java:1000)
    at 
org.apache.hadoop.hdfs.server.blockmanagement.BlockPlacementPolicyDefault.isGoodDatanode(BlockPlacementPolicyDefault.java:1086)
    at 
org.apache.hadoop.hdfs.server.blockmanagement.BlockPlacementPolicyDefault.chooseRandom(BlockPlacementPolicyDefault.java:855)
    at 
org.apache.hadoop.hdfs.server.blockmanagement.BlockPlacementPolicyDefault.chooseRemoteRack(BlockPlacementPolicyDefault.java:782)
    at 
org.apache.hadoop.hdfs.server.blockmanagement.BlockPlacementPolicyDefault.chooseTargetInOrder(BlockPlacementPolicyDefault.java:557)
    at 
org.apache.hadoop.hdfs.server.blockmanagement.BlockPlacementPolicyDefault.chooseTarget(BlockPlacementPolicyDefault.java:478)
    at 
org.apache.hadoop.hdfs.server.blockmanagement.BlockPlacementPolicyDefault.chooseTarget(BlockPlacementPolicyDefault.java:350)
    at 
org.apache.hadoop.hdfs.server.blockmanagement.BlockPlacementPolicyDefault.chooseTarget(BlockPlacementPolicyDefault.java:170)
    at 
org.apache.hadoop.hdfs.server.blockmanagement.ReplicationWork.chooseTargets(ReplicationWork.java:51)
    at 
org.apache.hadoop.hdfs.server.blockmanagement.BlockManager.computeReconstructionWorkForBlocks(BlockManager.java:2031)
    at 
org.apache.hadoop.hdfs.server.blockmanagement.TestBlockManager.scheduleSingleReplication(TestBlockManager.java:641)
    at 
org.apache.hadoop.hdfs.server.blockmanagement.TestBlockManager.doTestOneOfTwoRacksDecommissioned(TestBlockManager.java:364)
    at 
org.apache.hadoop.hdfs.server.blockmanagement.TestBlockManager.testOneOfTwoRacksDecommissioned(TestBlockManager.java:351){noformat}
For an easy reproduction, run the reproduce.sh in the attachment.

We are happy to provide a patch if this issue is confirmed.



--
This message was sent by Atlassian Jira
(v8.20.10#820010)

---------------------------------------------------------------------
To unsubscribe, e-mail: hdfs-issues-unsubscr...@hadoop.apache.org
For additional commands, e-mail: hdfs-issues-h...@hadoop.apache.org

Reply via email to