[Lustre-discuss] Huge Sparse files in ROOT partition of MDT

[Andreas Dilger]

On Mar 06, 2009  07:26 -0600, Nirmal Seenu wrote:
> While trying to figure out the reason for LVM2 snapshots failing on our 
> MDT server I found that there are a lot of sparse files on the MDT 
> volume. The file size as seen from a ls command output on the MDT is 
> same as the real file size. The tar runs for a few hours at this point 
> even if try to use the --spare option in the tar command.

All of the files on the MDT are sparse.  The data lives on the OSTs.

> The total MDT partition usage itself is about 500MB (as reported by df) 
> and it used to take me less than 10 minutes to create a LVM2 snapshot 
> and tar it up when I was running the servers using Lustre 1.6.5 with no 
> quota enabled.
> 
> I recently upgraded my Lustre servers to 1.6.7 and tried to enable quota 
> on the MDT and OST by doing the following commands:

Also, the quota file is a huge sparse file, size proportional to the
highest UID in use.


Cheers, Andreas
--
Andreas Dilger
Sr. Staff Engineer, Lustre Group
Sun Microsystems of Canada, Inc.