defrag

[Jerry McAllister]

On Sat, Mar 03, 2007 at 02:53:30PM +0100, Christian Baer wrote:

> On Thu, 1 Mar 2007 17:39:05 -0500 Jerry McAllister wrote:
> 
> >> Well, it would do some, but for the greatest effect, you would need:
> >>   dump + rm -rf * + restore
> >> That would get it all.
> 
> > Of course, I should have re-emphasized that this is not needed.
> > You will not improve performance.   Its only value might be to exercise
> > every used file block on the filesystem to make sure it is still
> > readable. And for that you don't need to nuke and rewrite things.
> 
> You could of try changing the above command into 'rm -rfP *'. That would
> make sure everything on your file system is still readable. And it would
> give you a lot of time to think about it. :-)
> 
> > Just doing the backup (which you should do anyway) will read up all
> > used file space (except what you might have marked as nodump).
> 
> Actually, that way you won't get every sector on the drive - not unless
> the drive is full to the brim anyway.

Note that I did say all of the _used_ space - eg actual files.

> 
> If you really just want to check the drive, use 
>   smartctl -t long /dev/whatever
> 
> You could also try
>   dd if=/dev/whatever of=/dev/null bs=1m
> 
> The idea with the backup isn't a bad one either. Cause if your drive
> goes up in flames, you don't really care. You still have your data.

Yup, just what I was sort of pointing out.

////jerry

> 
> Regards
> Chris
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