[
https://issues.apache.org/jira/browse/HDFS-4111?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13484954#comment-13484954
]
Todd Lipcon commented on HDFS-4111:
-----------------------------------
This seems to implement the O(n) algorithm for snapshot creation, rather than
the lazy method discussed in the other JIRAs. I don't think it's feasible to
use O(n) memory at snapshot creation time, per my comments elsewhere. I had
understood from that other discussion that you were planning to implement O(1)
usage at creation time, with up to O(m) usage after m modifications?
I can't imagine this working on a large subtree -- eg a few million files like
a hive warehouse dir.
Maybe we can reach agreement on the algorithm design before moving ahead with
too much code?
> Support snapshot of subtrees
> ----------------------------
>
> Key: HDFS-4111
> URL: https://issues.apache.org/jira/browse/HDFS-4111
> Project: Hadoop HDFS
> Issue Type: Sub-task
> Components: name-node
> Reporter: Tsz Wo (Nicholas), SZE
> Assignee: Tsz Wo (Nicholas), SZE
> Labels: needs-test
> Attachments: h4111_20121025.patch
>
>
> HDFS-4076 add the ability to take snapshot of single files. In this JIRA, we
> add the ability to take snapshot of subtree trees in the namesystem.
--
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
