[Lustre-discuss] backup MDT question

[Johann Lombardi]

On Thu, Apr 02, 2009 at 01:27:52PM -0500, Nirmal Seenu wrote:
> To reduce the size of the backup file use the "--sparse" option in your 
> tar command. This option only reduces the backup file size but not the 
> time taken to tar up your backup as tar keeps reading a whole bunch of 
> zeros from /dev/zero before it determines that the file is sparse.

In this particular case, no blocks are allocated, so tar actually does not
need to read the file content. This is something we can implement in our
lustre-aware tar (bug 15524). I'm going to file a bug for this.

Cheers,
Johann