[
https://issues.apache.org/jira/browse/HDFS-1477?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14981231#comment-14981231
]
Arpit Agarwal commented on HDFS-1477:
-------------------------------------
Hi [~xiaobingo], thanks for taking this up. My comments on the v5 patch:
# FsNameSystem and DatanodeManager need implement Reconfigurable, since their
Reconfigurable methods are only invoked via NameNode.
# What does getNewConf() do? Looks like it just constructs a new config object
by re-reading the config files? There should have been a Javadoc on the base
class method, perhaps we can add one now.
# Can we just skip implementing reconfiguration via the servlet? A better
approach is to have the daemon re-read its config files like HDFS-6808 (which
you pointed out to me offline :-). Looks like you will need a new RPC call and
support on the client. Also it would be good to log the reconfiguration request
in the hdfs audit log.
# Nitpicks: Fix indentation in DatanodeManager#reconfigurePropertyImpl.
# {{#reconfigurePropertyImpl}} - get {{namesystem.writeLock()}} outside the
{{try}} block.
Other suggestions for separate subtasks.
# The list of reconfigurable properties should not be hard-coded. We can add an
annotation to the reconfigurable properties.
# Add {{ReconfigurableBase}} support for atomic updates, i.e. all or no changes
take effect.
# Documentation.
> Make NameNode Reconfigurable.
> -----------------------------
>
> Key: HDFS-1477
> URL: https://issues.apache.org/jira/browse/HDFS-1477
> Project: Hadoop HDFS
> Issue Type: Sub-task
> Components: namenode
> Affects Versions: 2.7.0
> Reporter: Patrick Kling
> Assignee: Xiaobing Zhou
> Attachments: HDFS-1477.005.patch, HDFS-1477.2.patch,
> HDFS-1477.3.patch, HDFS-1477.4.patch, HDFS-1477.patch
>
>
> Modify NameNode to implement the interface Reconfigurable proposed in
> HADOOP-7001. This would allow us to change certain configuration properties
> without restarting the name node.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
