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https://issues.apache.org/jira/browse/YARN-3591?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14542347#comment-14542347
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zhihai xu commented on YARN-3591:
---------------------------------

[~vvasudev], that is a good suggestion, which will give better performance.
[~lavkesh], YARN-3491 implemented a signaling mechanism: DirsChangeListener.
We can register a DirsChangeListener for localDirs in LocalResourcesTrackerImpl 
by calling LocalDirsHandlerService#registerLocalDirsChangeListener. We can plug 
the resource removal code in the DirsChangeListener#onDirsChanged

> 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: 2.6.0
>            Reporter: Lavkesh Lahngir
>         Attachments: 0001-YARN-3591.1.patch, 0001-YARN-3591.patch, 
> YARN-3591.2.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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