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https://issues.apache.org/jira/browse/HADOOP-1978?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Konstantin Shvachko updated HADOOP-1978:
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Status: Patch Available (was: Open)
> Name-node should remove edits.new during startup rather than renaming it to
> edits.
> ----------------------------------------------------------------------------------
>
> Key: HADOOP-1978
> URL: https://issues.apache.org/jira/browse/HADOOP-1978
> Project: Hadoop
> Issue Type: Bug
> Components: dfs
> Affects Versions: 0.13.1
> Reporter: Konstantin Shvachko
> Assignee: Konstantin Shvachko
> Priority: Blocker
> Fix For: 0.14.2, 0.15.0
>
> Attachments: editsNew-0-14.patch, editsNew-0-15.patch
>
>
> Secondary name-node fails in the middle. The main name-node writes its
> journal transactions into edits.new at that time.
> If the name-node is shut down after that and restarted, then loadFSImage()
> reads current image file, merges it with the edits
> file and with the edits.new file.
> Now saveFSImage() saves new image file, creates empty edits file, and then
> calls rollFSImage(), which particularly renames
> edits.new into edits. This is a mistake, during startup edits.new should be
> merely removed after merging it with the image.
> The purpose of calling rollFSImage() during startups imho is to recover from
> an unsuccessful checkpoint. So an easy fix
> is to empty edits.new before calling rollFSImage the same as edits are
> emptied, then rollFSImage will rename empty file
> to empty which gives us the desired result.
> We should fix this bug both in 0.14 and 0.15. I make it a blocker for 0.15.
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