An interesting quirk

[Hal Duston]

On Sat, Jul 21, 2007 at 09:58:03AM -0500, Billy Crook wrote:
> I just rsynced everything on one fs to another of the same type and size.
> Both underlying disks arw partitioned the same, and of the same model
> number.  What could be causing this discrepancy in availiable space?
> 
> [BCrook at Desktop1 ~]$ df -h
> Filesystem            Size  Used Avail Use% Mounted on
> ....
> /dev/mapper/crypt     688G  561G  120G  83% /mnt/crypt
> /dev/mapper/crypt2    688G  561G   92G  86% /mnt/crypt2
> [BCrook at Desktop1 ~]$ mount
> .....
> /dev/mapper/crypt on /mnt/crypt type ext3 (rw)
> /dev/mapper/crypt2 on /mnt/crypt2 type ext3 (rw)

Check the reserved block count.  This is the count of filesystem
blocks reserved for the super-user.

tune2fs -l /dev/mapper/crypt
tune2fs -l /dev/mapper/crypt2

or

dumpe2fs -h /dev/mapper/crypt
dumpe2fs -h /dev/mapper/crypt2

At a guess, I'd say that crypt has a reserve of 0%, and crypt2 has a
reserve of 5%, which is the mke2fs default.

--
Hal Duston
hald at kc.rr.com