hadoop-hdfs-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Rakesh R (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (HDFS-11072) Add ability to unset and change directory EC policy
Date Fri, 28 Oct 2016 10:14:58 GMT

    [ https://issues.apache.org/jira/browse/HDFS-11072?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15615004#comment-15615004
] 

Rakesh R commented on HDFS-11072:
---------------------------------

Thanks [~Sammi], [~andrew.wang] for the good work. Just few thoughts.

bq.Agree, arbitrary replication factors should be supported
>From the jira subjectline I understand that the idea is to support unset/change EC policy
only on a directory and not on the file. Also, I think you are not planning to touch(ec to
non-ec while unsetting policy) any of the existing files under this directory on performing
this operation. In that case, do we need to care about the replication factor. IIUC, the directory
doesn't have the replication factor.  Am I missing anything?

bq. Later, if we want to change the whole directory A from EC1 to EC2, we have to recursively
go through all directories under A, change it one by one. It sounds not very convenient. 
Yes, imho, its not required to recursively go through all directories under a directory and
apply unset/change policy. Probably we could make this function call simple and apply the
changes only to the given directory. If user wants, then let them iterate and call this function
multiple times.

bq. And since EC policy on a directory is either inherited from its parent or explicitly set
by admin, we need a flag to indicate whether the policy is inherited or not
I'm interested to know, why do we differentiate that the policy is inherited from its parent
or explicitly set by admin.

> Add ability to unset and change directory EC policy
> ---------------------------------------------------
>
>                 Key: HDFS-11072
>                 URL: https://issues.apache.org/jira/browse/HDFS-11072
>             Project: Hadoop HDFS
>          Issue Type: Sub-task
>          Components: erasure-coding
>    Affects Versions: 3.0.0-alpha1
>            Reporter: Andrew Wang
>            Assignee: SammiChen
>              Labels: hdfs-ec-3.0-must-do
>
> Since the directory-level EC policy simply applies to files at create time, it makes
sense to make it more similar to storage policies and allow changing and unsetting the policy.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

---------------------------------------------------------------------
To unsubscribe, e-mail: hdfs-issues-unsubscribe@hadoop.apache.org
For additional commands, e-mail: hdfs-issues-help@hadoop.apache.org


Mime
View raw message