[
https://issues.apache.org/jira/browse/HADOOP-8469?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13288797#comment-13288797
]
Tsz Wo (Nicholas), SZE commented on HADOOP-8469:
------------------------------------------------
Hi Junping,
Thanks for posting a patch. Some quick comments:
- The patch moves InnerNode as a standalone class. Could you change
NetworkTopology.InnerNode to static and package private instead?
- There are a few tabs in the patch. (we do not use tabs in Hadoop)
- Some lines, mostly javadoc or comments, are very long. Could you change them
to <= 80 characters?
> Make NetworkTopology class pluggable
> ------------------------------------
>
> Key: HADOOP-8469
> URL: https://issues.apache.org/jira/browse/HADOOP-8469
> Project: Hadoop Common
> Issue Type: Sub-task
> Affects Versions: 1.0.0, 2.0.0-alpha
> Reporter: Junping Du
> Assignee: Junping Du
> Attachments: HADOOP-8469-NetworkTopology-pluggable-v2.patch,
> HADOOP-8469-NetworkTopology-pluggable.patch
>
>
> The class NetworkTopology is where the three-layer hierarchical topology is
> modeled in the current code base and is instantiated directly by the
> DatanodeManager and Balancer.
> To support alternative topologies, changes were make the topology class
> pluggable, that is to support using a user specified topology class specified
> in the Hadoop configuration file core-defaul.xml. The user specified topology
> class is instantiated using reflection in the same manner as other
> customizable classes in Hadoop. If no use specified topology class is found,
> the fallback is to use the NetworkTopology to preserve current behavior. To
> make it possible to reuse code in NetworkTopology several minor changes were
> made to make the class more extensible. The NetworkTopology class is
> currently annotated with @InterfaceAudience.LimitedPrivate({"HDFS",
> "MapReduce"}) and @InterfaceStability.Unstable.
> The proposed changes in NetworkTopology listed below
> 1. Some fields were changes from private to protected
> 2. Added some protected methods so that sub classes could override behavior
> 3. Added a new method,isNodeGroupAware,to NetworkTopology
> 4. The inner class InnerNode was made a package protected class to it would
> be easier to subclass
--
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
