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https://issues.apache.org/jira/browse/YARN-3591?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14583925#comment-14583925
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zhihai xu commented on YARN-3591:
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Hi [~vvasudev], thanks for the suggestion.
It looks like your suggestion is similar as [~lavkesh]'s original patch
0001-YARN-3591.patch. Compared to [~lavkesh]'s original patch, your suggestion
sometimes may not detect the disk failure because LocalDirHandlerService only
calls {{checkDirs}} every 2 minutes by default and if the disk failure happens
right after {{checkDirs}} is called and before {{isResourcePresent}} is called,
your suggestion won't detect the disk failure but [~lavkesh]'s original patch
can detect the disk failure. So it looks like [~lavkesh]'s original patch is
better than your suggestion. It is my understanding, and please correct me if I
am wrong.
> Resource Localisation on a bad disk causes subsequent containers failure
> -------------------------------------------------------------------------
>
> Key: YARN-3591
> URL: https://issues.apache.org/jira/browse/YARN-3591
> Project: Hadoop YARN
> Issue Type: Bug
> Affects Versions: 2.7.0
> Reporter: Lavkesh Lahngir
> Assignee: Lavkesh Lahngir
> Attachments: 0001-YARN-3591.1.patch, 0001-YARN-3591.patch,
> YARN-3591.2.patch, YARN-3591.3.patch, YARN-3591.4.patch
>
>
> It happens when a resource is localised on the disk, after localising that
> disk has gone bad. NM keeps paths for localised resources in memory. At the
> time of resource request isResourcePresent(rsrc) will be called which calls
> file.exists() on the localised path.
> In some cases when disk has gone bad, inodes are stilled cached and
> file.exists() returns true. But at the time of reading, file will not open.
> Note: file.exists() actually calls stat64 natively which returns true because
> it was able to find inode information from the OS.
> A proposal is to call file.list() on the parent path of the resource, which
> will call open() natively. If the disk is good it should return an array of
> paths with length at-least 1.
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