hadoop-hdfs-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Sanjay Radia (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (HDFS-3370) HDFS hardlink
Date Wed, 16 May 2012 03:30:23 GMT

    [ https://issues.apache.org/jira/browse/HDFS-3370?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13276415#comment-13276415
] 

Sanjay Radia commented on HDFS-3370:
------------------------------------

* I see the additional complexity in quotas because HDFS quotas are directory based (like
several file systems). I think this is addressable if we double count the quotas along both
path. 
* Permissions are not a problem since the file retains the file permissions and both paths
to the file offer their own permissions.
* I don't understand Srivas's rename example.
Srivas, in MapR I suspect that renames are only allowed within a volume and such hard links
would be supported only within a volume. Can you explain the problem with some more details.
                
> HDFS hardlink
> -------------
>
>                 Key: HDFS-3370
>                 URL: https://issues.apache.org/jira/browse/HDFS-3370
>             Project: Hadoop HDFS
>          Issue Type: New Feature
>            Reporter: Hairong Kuang
>            Assignee: Liyin Tang
>         Attachments: HDFS-HardLink.pdf
>
>
> We'd like to add a new feature hardlink to HDFS that allows harlinked files to share
data without copying. Currently we will support hardlinking only closed files, but it could
be extended to unclosed files as well.
> Among many potential use cases of the feature, the following two are primarily used in
facebook:
> 1. This provides a lightweight way for applications like hbase to create a snapshot;
> 2. This also allows an application like Hive to move a table to a different directory
without breaking current running hive queries.

--
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