Varun Vasudev commented on YARN-3591:

Thanks for the latest patch Lavkesh! Couple of comments -
Instead of 
+    this.dirsHandler = dirHandler;
in the new constructors you added, can you add that line to
LocalResourcesTrackerImpl(String user, ApplicationId appId,
      Dispatcher dispatcher,
      ConcurrentMap<LocalResourceRequest,LocalizedResource> localrsrc,
      boolean useLocalCacheDirectoryManager, Configuration conf,
      NMStateStoreService stateStore)
and have the other constructors call this one? Pass null for the directory 
handler if the existing constructors are called.

+      ret |= isParent(rsrc.getLocalPath().toUri().getPath(), dir);
We don't need to iterate through all the local dirs. Once ret is true we can 
break the loop and return.

Rest of the patch looks good.

> 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, YARN-3591.5.patch, 
> YARN-3591.6.patch, YARN-3591.7.patch, YARN-3591.8.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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