[HDFS-1465] Eliminate FS image loading code duplication between OIV and FSImage

• Type: Improvement
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 0.22.0
• Component/s: namenode
• Assignee: Jakob Homan
• Reporter: Aaron Myers
• Created: 20/Oct/10 14:48
• Updated: 18/Nov/10 05:12

Description

Konstantin wrote in HADOOP-5467:

Ideally we should have the same source code reading the fsimage file and then using different visitors to process deserialized data. I think we can achieve that goal by implementing a LoadFSImageVisitor, which will call FSNamesystem methods to add inodes to the directory tree and so on, making it a replacement to FSImage.loadFSImage().
The LoadFSImageVisitor can be passed to FSImageProcessor same as other visitors Jakob implemented.
We can do it in a separate Jira, but it should be done before the next release so that we had uniform deserialization in the release.
This approach will probably also require to move FSImageProcessor code inside server.namenode package. The OfflineImageViewer itself should remain in tools.

This work never got done, and it caused a problem in HDFS-1435. This JIRA is to track that work.

Issue Links

• is related to: HADOOP-5467 Create an offline fsimage image viewer
• is related to: HDFS-1435 Provide an option to store fsimage compressed
• relates to: HDFS-1506 Refactor fsimage loading code