[
https://issues.apache.org/jira/browse/HADOOP-8473?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Junping Du updated HADOOP-8473:
-------------------------------
Issue Type: Bug (was: Sub-task)
Parent: (was: HADOOP-8468)
> Update Balancer to support new NetworkTopology with NodeGroup
> -------------------------------------------------------------
>
> Key: HADOOP-8473
> URL: https://issues.apache.org/jira/browse/HADOOP-8473
> Project: Hadoop Common
> Issue Type: Bug
> Components: util
> Affects Versions: 1.0.0, 2.0.0-alpha
> Reporter: Junping Du
> Assignee: Junping Du
> Attachments: HADOOP-8473-Balancer-NodeGroup-aware.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:
https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira
