[
https://issues.apache.org/jira/browse/HADOOP-8852?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13469413#comment-13469413
]
Daryn Sharp commented on HADOOP-8852:
-------------------------------------
You raise good points and I've been wary of this class for awhile. Before
critiquing the patch, I now question the very existence of
{{DelegationTokenRenewer}}. Here's why:
Like all hdfs filesystems, a valid tgt is required obtain a token from the NN.
This calls into question the entire need for these filesystems to implicitly
obtain a token. If you can get a token, you don't need a token!
The api of this class also cannot handle multi-token filesystems so its not
generic enough to be of general utility. Furthermore, token renewal is
correctly handled within jobs so there's no need for a filesystem to internally
renew. One could make the case for a more generalized renewal outside of yarn,
but that would be another jira.
My recommendation is delete the class and all the logic in the filesystems that
use it.
> DelegationTokenRenewer should be Singleton
> ------------------------------------------
>
> Key: HADOOP-8852
> URL: https://issues.apache.org/jira/browse/HADOOP-8852
> Project: Hadoop Common
> Issue Type: Bug
> Affects Versions: 2.0.0-alpha
> Reporter: Tom White
> Assignee: Karthik Kambatla
> Attachments: hadoop-8852.patch, hadoop-8852.patch,
> hadoop-8852-v1.patch
>
>
> Updated description:
> DelegationTokenRenewer should be Singleton - the instance and renewer threads
> should be created/started lazily. The filesystems using the renewer shouldn't
> need to explicity start/stop the renewer, and only register/de-register for
> token renewal.
> Original issue:
> HftpFileSystem and WebHdfsFileSystem should stop the DelegationTokenRenewer
> thread when they are closed.
--
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
