hadoop-common-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Junping Du (JIRA)" <j...@apache.org>
Subject [jira] [Created] (HADOOP-8473) Update Balancer to support new NetworkTopology with NodeGroup
Date Mon, 04 Jun 2012 05:44:23 GMT
Junping Du created HADOOP-8473:
----------------------------------

             Summary: 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: Sub-task
          Components: util
    Affects Versions: 2.0.0-alpha, 1.0.0
            Reporter: Junping Du
            Assignee: Junping Du


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

        

Mime
View raw message