Backup Size

[Roland Smith]

On Mon, Aug 10, 2009 at 09:24:19PM -0500, Jay Hall wrote:
> 
> On Aug 10, 2009, at 12:09 PM, Roland Smith wrote:
> 
> >> The fact that you are using tar also plays a part. Tar has some  
> >> overhead to
> >> store information about the files it contains.
> 
> Is it possible to calculate the amount of overhead tar will use?

Just execute the tar command, and dump the output to /dev/null through dd:
tar -cf - /etc |dd of=/dev/null
tar: Removing leading '/' from member names
3160+0 records in
3160+0 records out
1617920 bytes transferred in 0.057690 secs (28045115 bytes/sec)

This will give you the exact size without writing anything to disk.

Roland
-- 
R.F.Smith                                   http://www.xs4all.nl/~rsmith/
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