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Posted to common-dev@hadoop.apache.org by "Konstantin Shvachko (JIRA)" <ji...@apache.org> on 2008/12/10 21:44:46 UTC
[jira] Created: (HADOOP-4826) Admin command saveNamespace.
Admin command saveNamespace.
----------------------------
Key: HADOOP-4826
URL: https://issues.apache.org/jira/browse/HADOOP-4826
Project: Hadoop Core
Issue Type: New Feature
Components: dfs
Reporter: Konstantin Shvachko
Assignee: Konstantin Shvachko
Fix For: 0.20.0
It would be useful to have an admin command that saves current namespace.
This command can be used before regular (planned) cluster shutdown.
The command will save the namespace into storage directory(s) and reset the name-node journal (edits file).
It will also reduce name-node startup time, because edits do not need to be digest.
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[jira] Commented: (HADOOP-4826) Admin command saveNamespace.
Posted by "Tsz Wo (Nicholas), SZE (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/HADOOP-4826?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12656110#action_12656110 ]
Tsz Wo (Nicholas), SZE commented on HADOOP-4826:
------------------------------------------------
+1 patch looks good. Below are the ant test-patch results.
{noformat}
[exec] +1 overall.
[exec] +1 @author. The patch does not contain any @author tags.
[exec] +1 tests included. The patch appears to include 3 new or modified tests.
[exec] +1 javadoc. The javadoc tool did not generate any warning messages.
[exec] +1 javac. The applied patch does not increase the total number of javac compiler warnings.
[exec] +1 findbugs. The patch does not introduce any new Findbugs warnings.
[exec] +1 Eclipse classpath. The patch retains Eclipse classpath integrity.
{noformat}
> Admin command saveNamespace.
> ----------------------------
>
> Key: HADOOP-4826
> URL: https://issues.apache.org/jira/browse/HADOOP-4826
> Project: Hadoop Core
> Issue Type: New Feature
> Components: dfs
> Reporter: Konstantin Shvachko
> Assignee: Konstantin Shvachko
> Fix For: 0.20.0
>
> Attachments: saveNamespace.patch, saveNamespace.patch, saveNamespace.patch
>
>
> It would be useful to have an admin command that saves current namespace.
> This command can be used before regular (planned) cluster shutdown.
> The command will save the namespace into storage directory(s) and reset the name-node journal (edits file).
> It will also reduce name-node startup time, because edits do not need to be digest.
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[jira] Updated: (HADOOP-4826) Admin command saveNamespace.
Posted by "Konstantin Shvachko (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/HADOOP-4826?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Konstantin Shvachko updated HADOOP-4826:
----------------------------------------
Status: Open (was: Patch Available)
> Admin command saveNamespace.
> ----------------------------
>
> Key: HADOOP-4826
> URL: https://issues.apache.org/jira/browse/HADOOP-4826
> Project: Hadoop Core
> Issue Type: New Feature
> Components: dfs
> Reporter: Konstantin Shvachko
> Assignee: Konstantin Shvachko
> Fix For: 0.20.0
>
> Attachments: saveNamespace.patch, saveNamespace.patch, saveNamespace.patch
>
>
> It would be useful to have an admin command that saves current namespace.
> This command can be used before regular (planned) cluster shutdown.
> The command will save the namespace into storage directory(s) and reset the name-node journal (edits file).
> It will also reduce name-node startup time, because edits do not need to be digest.
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[jira] Updated: (HADOOP-4826) Admin command saveNamespace.
Posted by "Konstantin Shvachko (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/HADOOP-4826?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Konstantin Shvachko updated HADOOP-4826:
----------------------------------------
Status: Patch Available (was: Open)
> Admin command saveNamespace.
> ----------------------------
>
> Key: HADOOP-4826
> URL: https://issues.apache.org/jira/browse/HADOOP-4826
> Project: Hadoop Core
> Issue Type: New Feature
> Components: dfs
> Reporter: Konstantin Shvachko
> Assignee: Konstantin Shvachko
> Fix For: 0.20.0
>
> Attachments: saveNamespace.patch
>
>
> It would be useful to have an admin command that saves current namespace.
> This command can be used before regular (planned) cluster shutdown.
> The command will save the namespace into storage directory(s) and reset the name-node journal (edits file).
> It will also reduce name-node startup time, because edits do not need to be digest.
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[jira] Commented: (HADOOP-4826) Admin command saveNamespace.
Posted by "Tsz Wo (Nicholas), SZE (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/HADOOP-4826?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12656180#action_12656180 ]
Tsz Wo (Nicholas), SZE commented on HADOOP-4826:
------------------------------------------------
> In general we do not promote new features to earlier releases.
> But if there is a need to do that with this one let me know.
Even there is a need, we could not promote this to earlier releases since this is a incompatible change.
> Admin command saveNamespace.
> ----------------------------
>
> Key: HADOOP-4826
> URL: https://issues.apache.org/jira/browse/HADOOP-4826
> Project: Hadoop Core
> Issue Type: New Feature
> Components: dfs
> Reporter: Konstantin Shvachko
> Assignee: Konstantin Shvachko
> Fix For: 0.20.0
>
> Attachments: saveNamespace.patch, saveNamespace.patch, saveNamespace.patch
>
>
> It would be useful to have an admin command that saves current namespace.
> This command can be used before regular (planned) cluster shutdown.
> The command will save the namespace into storage directory(s) and reset the name-node journal (edits file).
> It will also reduce name-node startup time, because edits do not need to be digest.
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[jira] Commented: (HADOOP-4826) Admin command saveNamespace.
Posted by "Suresh Srinivas (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/HADOOP-4826?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12655565#action_12655565 ]
Suresh Srinivas commented on HADOOP-4826:
-----------------------------------------
Should we have a version of stopping the namenode gracefully, which automatically does the manual steps proposed in this change?
> Admin command saveNamespace.
> ----------------------------
>
> Key: HADOOP-4826
> URL: https://issues.apache.org/jira/browse/HADOOP-4826
> Project: Hadoop Core
> Issue Type: New Feature
> Components: dfs
> Reporter: Konstantin Shvachko
> Assignee: Konstantin Shvachko
> Fix For: 0.20.0
>
> Attachments: saveNamespace.patch
>
>
> It would be useful to have an admin command that saves current namespace.
> This command can be used before regular (planned) cluster shutdown.
> The command will save the namespace into storage directory(s) and reset the name-node journal (edits file).
> It will also reduce name-node startup time, because edits do not need to be digest.
--
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[jira] Updated: (HADOOP-4826) Admin command saveNamespace.
Posted by "Konstantin Shvachko (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/HADOOP-4826?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Konstantin Shvachko updated HADOOP-4826:
----------------------------------------
Attachment: saveNamespace.patch
Forgot to remove public after doing some testing. Change getName() to getURI(). This makes sense since I fixed 2 warnings anyway.
I was also thinking about a real shutdown command, don't think we should introduce it now.
> Admin command saveNamespace.
> ----------------------------
>
> Key: HADOOP-4826
> URL: https://issues.apache.org/jira/browse/HADOOP-4826
> Project: Hadoop Core
> Issue Type: New Feature
> Components: dfs
> Reporter: Konstantin Shvachko
> Assignee: Konstantin Shvachko
> Fix For: 0.20.0
>
> Attachments: saveNamespace.patch, saveNamespace.patch
>
>
> It would be useful to have an admin command that saves current namespace.
> This command can be used before regular (planned) cluster shutdown.
> The command will save the namespace into storage directory(s) and reset the name-node journal (edits file).
> It will also reduce name-node startup time, because edits do not need to be digest.
--
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[jira] Updated: (HADOOP-4826) Admin command saveNamespace.
Posted by "Konstantin Shvachko (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/HADOOP-4826?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Konstantin Shvachko updated HADOOP-4826:
----------------------------------------
Attachment: saveNamespace.patch
saveNamespace will save the namespace image directly to disk(s), it does not need to replay the journal.
Since saving the image is much faster than digesting the edits the command can substantially reduce the overall cluster restart time.
Recommended procedure for restarting the cluster:
# enter safe mode
# save namespace
# shutdown the cluster
# start the cluster
The patch introduces a new {{DFSAdmin}} command which is called using
{code}
hadoop dfsadmin -saveNamespace
{code}
As all other {{DFSAdmin}} commands it requires *superuser permissions*.
In addition, the name-node *must be in safe mode*, because we don't want to allow changing namespace during the save.
In order to enter safe mode call
{code}
hadoop dfsadmin -safemode enter
{code}
The patch also corrects 2 warnings in TestCheckpoint, and 2 Javadoc warnings in FSNamesystem.
> Admin command saveNamespace.
> ----------------------------
>
> Key: HADOOP-4826
> URL: https://issues.apache.org/jira/browse/HADOOP-4826
> Project: Hadoop Core
> Issue Type: New Feature
> Components: dfs
> Reporter: Konstantin Shvachko
> Assignee: Konstantin Shvachko
> Fix For: 0.20.0
>
> Attachments: saveNamespace.patch
>
>
> It would be useful to have an admin command that saves current namespace.
> This command can be used before regular (planned) cluster shutdown.
> The command will save the namespace into storage directory(s) and reset the name-node journal (edits file).
> It will also reduce name-node startup time, because edits do not need to be digest.
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[jira] Commented: (HADOOP-4826) Admin command saveNamespace.
Posted by "Lohit Vijayarenu (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/HADOOP-4826?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12655783#action_12655783 ]
Lohit Vijayarenu commented on HADOOP-4826:
------------------------------------------
This looks good. One minor comment if it would help. In the testcase, it would be good to create files, save namespace, stop namenode, start namenode and validate files.
> Admin command saveNamespace.
> ----------------------------
>
> Key: HADOOP-4826
> URL: https://issues.apache.org/jira/browse/HADOOP-4826
> Project: Hadoop Core
> Issue Type: New Feature
> Components: dfs
> Reporter: Konstantin Shvachko
> Assignee: Konstantin Shvachko
> Fix For: 0.20.0
>
> Attachments: saveNamespace.patch, saveNamespace.patch
>
>
> It would be useful to have an admin command that saves current namespace.
> This command can be used before regular (planned) cluster shutdown.
> The command will save the namespace into storage directory(s) and reset the name-node journal (edits file).
> It will also reduce name-node startup time, because edits do not need to be digest.
--
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[jira] Commented: (HADOOP-4826) Admin command saveNamespace.
Posted by "Suresh Srinivas (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/HADOOP-4826?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12655564#action_12655564 ]
Suresh Srinivas commented on HADOOP-4826:
-----------------------------------------
- In DistributedFileSystem.java, not sure why DFSClient is made a public member. The code compiles without it.
- In DFSAdmin.refreshNodes, deprecated method fs.getName() can be replaced with fs.getUri();
> Admin command saveNamespace.
> ----------------------------
>
> Key: HADOOP-4826
> URL: https://issues.apache.org/jira/browse/HADOOP-4826
> Project: Hadoop Core
> Issue Type: New Feature
> Components: dfs
> Reporter: Konstantin Shvachko
> Assignee: Konstantin Shvachko
> Fix For: 0.20.0
>
> Attachments: saveNamespace.patch
>
>
> It would be useful to have an admin command that saves current namespace.
> This command can be used before regular (planned) cluster shutdown.
> The command will save the namespace into storage directory(s) and reset the name-node journal (edits file).
> It will also reduce name-node startup time, because edits do not need to be digest.
--
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[jira] Commented: (HADOOP-4826) Admin command saveNamespace.
Posted by "Tsz Wo (Nicholas), SZE (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/HADOOP-4826?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12682384#action_12682384 ]
Tsz Wo (Nicholas), SZE commented on HADOOP-4826:
------------------------------------------------
> 6. I'd prefer to change documentation in a follow up issue.
Hi Konstantin, please create a follow up issue if you haven't.
> Admin command saveNamespace.
> ----------------------------
>
> Key: HADOOP-4826
> URL: https://issues.apache.org/jira/browse/HADOOP-4826
> Project: Hadoop Core
> Issue Type: New Feature
> Components: dfs
> Reporter: Konstantin Shvachko
> Assignee: Konstantin Shvachko
> Fix For: 0.20.0
>
> Attachments: saveNamespace.patch, saveNamespace.patch, saveNamespace.patch
>
>
> It would be useful to have an admin command that saves current namespace.
> This command can be used before regular (planned) cluster shutdown.
> The command will save the namespace into storage directory(s) and reset the name-node journal (edits file).
> It will also reduce name-node startup time, because edits do not need to be digest.
--
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[jira] Commented: (HADOOP-4826) Admin command saveNamespace.
Posted by "Tsz Wo (Nicholas), SZE (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/HADOOP-4826?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12655833#action_12655833 ]
Tsz Wo (Nicholas), SZE commented on HADOOP-4826:
------------------------------------------------
- Patch cannot be applied to trunk.
- DFSClient.saveNamespace() should not be public.
- Update ClientProtocol version
- In the javadoc of FSNamesystem.saveNamespace(),
-* Change "superuser permission" to "superuser privilege"
-* Change "permission status is not superuser" to "current user is not a superuser"
- Should update forrest doc.
> Admin command saveNamespace.
> ----------------------------
>
> Key: HADOOP-4826
> URL: https://issues.apache.org/jira/browse/HADOOP-4826
> Project: Hadoop Core
> Issue Type: New Feature
> Components: dfs
> Reporter: Konstantin Shvachko
> Assignee: Konstantin Shvachko
> Fix For: 0.20.0
>
> Attachments: saveNamespace.patch, saveNamespace.patch
>
>
> It would be useful to have an admin command that saves current namespace.
> This command can be used before regular (planned) cluster shutdown.
> The command will save the namespace into storage directory(s) and reset the name-node journal (edits file).
> It will also reduce name-node startup time, because edits do not need to be digest.
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[jira] Issue Comment Edited: (HADOOP-4826) Admin command
saveNamespace.
Posted by "Konstantin Shvachko (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/HADOOP-4826?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12655923#action_12655923 ]
shv edited comment on HADOOP-4826 at 12/12/08 12:40 AM:
------------------------------------------------------------------------
# Merged with current trunk.
# Incorporated Lohit's comments.
# In addition made the test to verify that the edits file is not empty after adding a new file, but is empty after saving the namespace.
# incorporated Nicholas's comments.
# Also included unwrapping of the AccessControlException in DFSClient.
# I'd prefer to change documentation in a follow up issue.
was (Author: shv):
# Incorporated Lohit's comments.
# In addition the test verifies that the edits file is not empty after adding a new file, but is empty after saving namespace.
# incorporated Nicholas's comments.
# I'd prefer to change documentation in a follow up issue.
> Admin command saveNamespace.
> ----------------------------
>
> Key: HADOOP-4826
> URL: https://issues.apache.org/jira/browse/HADOOP-4826
> Project: Hadoop Core
> Issue Type: New Feature
> Components: dfs
> Reporter: Konstantin Shvachko
> Assignee: Konstantin Shvachko
> Fix For: 0.20.0
>
> Attachments: saveNamespace.patch, saveNamespace.patch, saveNamespace.patch
>
>
> It would be useful to have an admin command that saves current namespace.
> This command can be used before regular (planned) cluster shutdown.
> The command will save the namespace into storage directory(s) and reset the name-node journal (edits file).
> It will also reduce name-node startup time, because edits do not need to be digest.
--
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[jira] Updated: (HADOOP-4826) Admin command saveNamespace.
Posted by "Konstantin Shvachko (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/HADOOP-4826?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Konstantin Shvachko updated HADOOP-4826:
----------------------------------------
Hadoop Flags: [Incompatible change, Reviewed] (was: [Incompatible change])
Status: Patch Available (was: Open)
> Admin command saveNamespace.
> ----------------------------
>
> Key: HADOOP-4826
> URL: https://issues.apache.org/jira/browse/HADOOP-4826
> Project: Hadoop Core
> Issue Type: New Feature
> Components: dfs
> Reporter: Konstantin Shvachko
> Assignee: Konstantin Shvachko
> Fix For: 0.20.0
>
> Attachments: saveNamespace.patch, saveNamespace.patch, saveNamespace.patch
>
>
> It would be useful to have an admin command that saves current namespace.
> This command can be used before regular (planned) cluster shutdown.
> The command will save the namespace into storage directory(s) and reset the name-node journal (edits file).
> It will also reduce name-node startup time, because edits do not need to be digest.
--
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[jira] Updated: (HADOOP-4826) Admin command saveNamespace.
Posted by "Konstantin Shvachko (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/HADOOP-4826?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Konstantin Shvachko updated HADOOP-4826:
----------------------------------------
Attachment: saveNamespace.patch
# Incorporated Lohit's comments.
# In addition the test verifies that the edits file is not empty after adding a new file, but is empty after saving namespace.
# incorporated Nicholas's comments.
# I'd prefer to change documentation in a follow up issue.
> Admin command saveNamespace.
> ----------------------------
>
> Key: HADOOP-4826
> URL: https://issues.apache.org/jira/browse/HADOOP-4826
> Project: Hadoop Core
> Issue Type: New Feature
> Components: dfs
> Reporter: Konstantin Shvachko
> Assignee: Konstantin Shvachko
> Fix For: 0.20.0
>
> Attachments: saveNamespace.patch, saveNamespace.patch, saveNamespace.patch
>
>
> It would be useful to have an admin command that saves current namespace.
> This command can be used before regular (planned) cluster shutdown.
> The command will save the namespace into storage directory(s) and reset the name-node journal (edits file).
> It will also reduce name-node startup time, because edits do not need to be digest.
--
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[jira] Updated: (HADOOP-4826) Admin command saveNamespace.
Posted by "Konstantin Shvachko (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/HADOOP-4826?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Konstantin Shvachko updated HADOOP-4826:
----------------------------------------
Resolution: Fixed
Hadoop Flags: [Incompatible change, Reviewed] (was: [Reviewed, Incompatible change])
Status: Resolved (was: Patch Available)
I just committed this.
In general we do not promote new features to earlier releases.
But if there is a need to do that with this one let me know.
> Admin command saveNamespace.
> ----------------------------
>
> Key: HADOOP-4826
> URL: https://issues.apache.org/jira/browse/HADOOP-4826
> Project: Hadoop Core
> Issue Type: New Feature
> Components: dfs
> Reporter: Konstantin Shvachko
> Assignee: Konstantin Shvachko
> Fix For: 0.20.0
>
> Attachments: saveNamespace.patch, saveNamespace.patch, saveNamespace.patch
>
>
> It would be useful to have an admin command that saves current namespace.
> This command can be used before regular (planned) cluster shutdown.
> The command will save the namespace into storage directory(s) and reset the name-node journal (edits file).
> It will also reduce name-node startup time, because edits do not need to be digest.
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[jira] Updated: (HADOOP-4826) Admin command saveNamespace.
Posted by "Robert Chansler (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/HADOOP-4826?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Robert Chansler updated HADOOP-4826:
------------------------------------
Release Note: Introduced new dfsadmin command saveNamespace to command the name service to do an immediate save of the file system image.
Hadoop Flags: [Incompatible change, Reviewed] (was: [Reviewed, Incompatible change])
Edit release note for publication.
> Admin command saveNamespace.
> ----------------------------
>
> Key: HADOOP-4826
> URL: https://issues.apache.org/jira/browse/HADOOP-4826
> Project: Hadoop Core
> Issue Type: New Feature
> Components: dfs
> Reporter: Konstantin Shvachko
> Assignee: Konstantin Shvachko
> Fix For: 0.20.0
>
> Attachments: saveNamespace.patch, saveNamespace.patch, saveNamespace.patch
>
>
> It would be useful to have an admin command that saves current namespace.
> This command can be used before regular (planned) cluster shutdown.
> The command will save the namespace into storage directory(s) and reset the name-node journal (edits file).
> It will also reduce name-node startup time, because edits do not need to be digest.
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[jira] Updated: (HADOOP-4826) Admin command saveNamespace.
Posted by "Tsz Wo (Nicholas), SZE (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/HADOOP-4826?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Tsz Wo (Nicholas), SZE updated HADOOP-4826:
-------------------------------------------
Hadoop Flags: [Incompatible change]
> In addition, the name-node must be in safe mode, because we don't want to allow changing namespace during the save.
Safe mode may not be required since the namespace lock is acquired before saving images. Consider that saving images may take a long time, it makes sense to set safe mode.
> Admin command saveNamespace.
> ----------------------------
>
> Key: HADOOP-4826
> URL: https://issues.apache.org/jira/browse/HADOOP-4826
> Project: Hadoop Core
> Issue Type: New Feature
> Components: dfs
> Reporter: Konstantin Shvachko
> Assignee: Konstantin Shvachko
> Fix For: 0.20.0
>
> Attachments: saveNamespace.patch, saveNamespace.patch
>
>
> It would be useful to have an admin command that saves current namespace.
> This command can be used before regular (planned) cluster shutdown.
> The command will save the namespace into storage directory(s) and reset the name-node journal (edits file).
> It will also reduce name-node startup time, because edits do not need to be digest.
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