[conspire] PING (Partimage Is Not Ghost) -- Backup and Restore Disk Partitions

[David Fox]

On 2/22/08, Rick Moen <rick at linuxmafia.com> wrote:
> Quoting Daniel Gimpelevich (daniel at gimpelevich.san-francisco.ca.us):
>
> > Using "j" instead of "z" gives bzip2 instead of gzip:
> > tar Scjp -C dir . | ssh username at newhost 'tar Sxvjp -C /mnt/somewhere'
>
> At the cost of absolutely hideous performance overhead that is seldom
> possible to justify for the 10% gain in compression.

Quite. The few times (not over ssh, mind you) that I've attempted to
use file by file compression (usually   requiring something like afio)
the performance overhead has been too much IMHO to justify using
anything more than the minimal compression, if any at all. The last
time I tried  to do a dvd backup of my system with mondo[1] (which
offers this capability) I let the backup start, went to bed, and when
I got up the next morning, it still hadn't gotten the fileset for
dvd#1 ready for burning.

This sort of illustrates a point I was making at last night's cabal in
response to your point about why users are starting not to make
regular backups. People are continually migrating to  bigger drives,
necessitating much more time just to make the backup sets, and even
things like DvD media backups only seem to make sense if the data
you're backing up is less than 4.5 gigs (and you manage to keep
/home's usage far below 4.5 gigs, because even without compression,
the backup is likely to take a very long time on aging machines like
mine.

OTOH, I don't want to have to go back to using only 1.9 gigs worth of
space, which would have fit beautifully just one one 4mm DAT tape, no
compression needed, just use 'tar'. :)


[1] howto writeup at: http://www.mondorescue.org/docs/mondorescue-howto.html