[
https://issues.apache.org/jira/browse/HDFS-3495?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13672082#comment-13672082
]
Hadoop QA commented on HDFS-3495:
---------------------------------
{color:red}-1 overall{color}. Here are the results of testing the latest
attachment
http://issues.apache.org/jira/secure/attachment/12585722/HDFS-3495-branch-2.patch
against trunk revision .
{color:red}-1 patch{color}. The patch command could not apply the patch.
Console output: https://builds.apache.org/job/PreCommit-HDFS-Build/4466//console
This message is automatically generated.
> Update Balancer to support new NetworkTopology with NodeGroup
> -------------------------------------------------------------
>
> Key: HDFS-3495
> URL: https://issues.apache.org/jira/browse/HDFS-3495
> Project: Hadoop HDFS
> Issue Type: New Feature
> Components: balancer
> Reporter: Junping Du
> Assignee: Junping Du
> Fix For: 1.2.0, 3.0.0
>
> Attachments: HADOOP-8473-Balancer-NodeGroup-aware.patch,
> HDFS-3495-branch-2.patch, HDFS-3495-v2.patch, HDFS-3495-v3.patch,
> HDFS-3495-v4.patch, HDFS-3495-v5.patch
>
>
> Since the Balancer is a Hadoop Tool, it was updated to be directly aware of
> four-layer hierarchy instead of creating an alternative Balancer
> implementation. To accommodate extensibility, a new protected method,
> doChooseNodesForCustomFaultDomain is now called from the existing chooseNodes
> method so that a subclass of the Balancer could customize the balancer
> algotirhm for other failure and locality topologies. An alternative option is
> to encapsulate the algorithm used for the four-layer hierarchy into a
> collaborating strategy class.
> The key changes introduced to support a four-layer hierarchy were to override
> the algorithm of choosing <source, target> pairs for balancing. Unit tests
> were created to test the new algorithm.
> The algorithm now makes sure to choose the target and source node on the same
> node group for balancing as the first priority. Then the overall balancing
> policy is: first doing balancing between nodes within the same nodegroup then
> the same rack and off rack at last. Also, we need to check no duplicated
> replicas live in the same node group after balancing.
--
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
