Mailing-List: contact hdfs-issues-help@hadoop.apache.org; run by ezmlm
Precedence: bulk
Reply-To: hdfs-issues@hadoop.apache.org
Date: Mon, 22 Dec 2014 01:37:15 +0000 (UTC)
From: "Konstantin Shvachko (JIRA)" <jira@apache.org>
To: hdfs-issues@hadoop.apache.org
Message-ID: <JIRA.12741140.1410548616000.81887.1419212235243@Atlassian.JIRA>
In-Reply-To: <JIRA.12741140.1410548616000@Atlassian.JIRA>
References: <JIRA.12741140.1410548616000@Atlassian.JIRA>
 <JIRA.12741140.1410548616885@arcas>
Subject: [jira] [Updated] (HDFS-7056) Snapshot support for truncate
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 7bit


     [ https://issues.apache.org/jira/browse/HDFS-7056?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Konstantin Shvachko updated HDFS-7056:
--------------------------------------
    Attachment: HDFS-7056-13.patch

Here is what we did in the new patch.
- Jing it was very good catch with persisting snapshot blocks into fsimage. My fault. I thought it was covered by our tests, because we have a bunch of restarts, but it turned out restart does not save the image as it used before.
New patch persists snapshot blocks and adds a test case, which explicitly saves namespace before restarting.
- Also bumped up the NameNode layout version.
- Added optimized {{findLaterSnapshotBlocks()}}
- Did the renames requested by Colin.
- Added default value for the newBlockId field.
-- This actually raised a question for me how it will work with rolling upgrades. Thinking about it.
- Colin, I did not introduce enum as the return value. I would have if there were three or more values or a potential to have more. But its exactly two. You are right we cannot change {{recoverLease()}} now. So it is better to have the same pattern in {{truncate()}} to avoid even more confusion why this is done differently in two cases.
Anyways we clearly disagree, so it would be good if anybody esle could weigh on the subject.

> Snapshot support for truncate
> -----------------------------
>
>                 Key: HDFS-7056
>                 URL: https://issues.apache.org/jira/browse/HDFS-7056
>             Project: Hadoop HDFS
>          Issue Type: Sub-task
>          Components: namenode
>    Affects Versions: 3.0.0
>            Reporter: Konstantin Shvachko
>            Assignee: Plamen Jeliazkov
>         Attachments: HDFS-3107-HDFS-7056-combined.patch, HDFS-3107-HDFS-7056-combined.patch, HDFS-3107-HDFS-7056-combined.patch, HDFS-3107-HDFS-7056-combined.patch, HDFS-3107-HDFS-7056-combined.patch, HDFS-3107-HDFS-7056-combined.patch, HDFS-3107-HDFS-7056-combined.patch, HDFS-3107-HDFS-7056-combined.patch, HDFS-3107-HDFS-7056-combined.patch, HDFS-7056-13.patch, HDFS-7056.patch, HDFS-7056.patch, HDFS-7056.patch, HDFS-7056.patch, HDFS-7056.patch, HDFS-7056.patch, HDFS-7056.patch, HDFS-7056.patch, HDFSSnapshotWithTruncateDesign.docx
>
>
> Implementation of truncate in HDFS-3107 does not allow truncating files which are in a snapshot. It is desirable to be able to truncate and still keep the old file state of the file in the snapshot.


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