[ 
https://issues.apache.org/jira/browse/HDFS-4937?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13726787#comment-13726787
 ] 

Hadoop QA commented on HDFS-4937:
---------------------------------

{color:red}-1 overall{color}.  Here are the results of testing the latest 
attachment 
  http://issues.apache.org/jira/secure/attachment/12595453/HDFS-4937.patch
  against trunk revision .

    {color:green}+1 @author{color}.  The patch does not contain any @author 
tags.

    {color:red}-1 tests included{color}.  The patch doesn't appear to include 
any new or modified tests.
                        Please justify why no new tests are needed for this 
patch.
                        Also please list what manual steps were performed to 
verify this patch.

    {color:green}+1 javac{color}.  The applied patch does not increase the 
total number of javac compiler warnings.

    {color:green}+1 javadoc{color}.  The javadoc tool did not generate any 
warning messages.

    {color:green}+1 eclipse:eclipse{color}.  The patch built with 
eclipse:eclipse.

    {color:green}+1 findbugs{color}.  The patch does not introduce any new 
Findbugs (version 1.3.9) warnings.

    {color:green}+1 release audit{color}.  The applied patch does not increase 
the total number of release audit warnings.

    {color:green}+1 core tests{color}.  The patch passed unit tests in 
hadoop-hdfs-project/hadoop-hdfs.

    {color:green}+1 contrib tests{color}.  The patch passed contrib unit tests.

Test results: 
https://builds.apache.org/job/PreCommit-HDFS-Build/4754//testReport/
Console output: https://builds.apache.org/job/PreCommit-HDFS-Build/4754//console

This message is automatically generated.
                
> ReplicationMonitor can infinite-loop in 
> BlockPlacementPolicyDefault#chooseRandom()
> ----------------------------------------------------------------------------------
>
>                 Key: HDFS-4937
>                 URL: https://issues.apache.org/jira/browse/HDFS-4937
>             Project: Hadoop HDFS
>          Issue Type: Bug
>          Components: namenode
>    Affects Versions: 2.0.4-alpha, 0.23.8
>            Reporter: Kihwal Lee
>         Attachments: HDFS-4937.patch
>
>
> When a large number of nodes are removed by refreshing node lists, the 
> network topology is updated. If the refresh happens at the right moment, the 
> replication monitor thread may stuck in the while loop of {{chooseRandom()}}. 
> This is because the cached cluster size is used in the terminal condition 
> check of the loop. This usually happens when a block with a high replication 
> factor is being processed. Since replicas/rack is also calculated beforehand, 
> no node choice may satisfy the goodness criteria if refreshing removed racks. 
> All nodes will end up in the excluded list, but the size will still be less 
> than the cached cluster size, so it will loop infinitely. This was observed 
> in a production environment.

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira

Reply via email to