NameNode should save the root inode into fsimage

• Key: HADOOP-3409
• Type: Bug
• Status: Closed
• Resolution: Fixed
• Priority: Major
• Assignee: Hairong Kuang
• Reporter: Hairong Kuang
• Affects Version/s: 0.16.4
• Fix Version/s: 0.18.0

Description

Currently namenode does not save the root inode into the image. Therefore the root's attributes like modification time, permission, and quota in the future are not persistent.

Comments

[Hairong Kuang]

A patch that attempts to fix the problem.

[Tsz Wo (Nicholas), SZE]

Is it correct that root path has (path.length() == 0) ?

[dhruba borthakur]

In this patch, the loadFSImage method does the following:

if (path.length() == 0) {
// assume that this is the root inode.
}

will it be more explicit if we replace the above piece of code with the following:

if (i == 0) {
// the first entry is always the root inode.
}

[Hairong Kuang]

if we take Dhruba's suggestion, then we need to bump up the image version number.

[Hairong Kuang]

> is it correct that root path has (path.length() == 0)
This how INode.isRoot() is implemented.

[Hairong Kuang]

This is a patch with a modified unit test that makes sure that the root is saved to the disk.

[Hadoop QA]

+1 overall. Here are the results of testing the latest attachment
http://issues.apache.org/jira/secure/attachment/12382323/rootImage1.patch
against trunk revision 657903.

+1 @author. The patch does not contain any @author tags.

+1 tests included. The patch appears to include 3 new or modified tests.

+1 javadoc. The javadoc tool did not generate any warning messages.

+1 javac. The applied patch does not increase the total number of javac compiler warnings.

+1 findbugs. The patch does not introduce any new Findbugs warnings.

+1 release audit. The applied patch does not increase the total number of release audit warnings.

+1 core tests. The patch passed core unit tests.

+1 contrib tests. The patch passed contrib unit tests.

Test results: http://hudson.zones.apache.org/hudson/job/Hadoop-Patch/2499/testReport/
Findbugs warnings: http://hudson.zones.apache.org/hudson/job/Hadoop-Patch/2499/artifact/trunk/build/test/findbugs/newPatchFindbugsWarnings.html
Checkstyle results: http://hudson.zones.apache.org/hudson/job/Hadoop-Patch/2499/artifact/trunk/build/test/checkstyle-errors.html
Console output: http://hudson.zones.apache.org/hudson/job/Hadoop-Patch/2499/console

This message is automatically generated.

[Tsz Wo (Nicholas), SZE]

+1 patch looks good.

[Hairong Kuang]

I just committed this.

[Hudson]

Integrated in Hadoop-trunk #499 (See http://hudson.zones.apache.org/hudson/job/Hadoop-trunk/499/)