On Sat, 2 Mar 2002, David S. wrote:

> > >
> > > I heard that by using ccd (concatenated/striped disk devices), one can
> > > improve the disk I/O.  I read the manual (ccd) but it's more of dictionary of

IMCHO, ccd(4) is extremely simplistic implementation of RAID0, not even
worth having a pairity/stripe (hence my example on the guide doesn't
mention it).

It's good for making a big file system mount accros disks of different
sizes (like all those mp3s of CDs you own that you're legally allowed to
have one backup copy of >:} )

If you're serious about RAID0, use RaidFrame (which requires disks of the
_exact same geometry_).


-lava

> >
> > You have only one disk ?
> > ccd improves disk I/O by spreading the load accross several disks. With
> > only one disk ccd won't help at all.
>
> Also note that if you put two disks in simple stripe - which you'd do if
> you just wanted to improve I/O performance - you double the the chance
> of disk failure making your data inacessible.  A simple stripe or
> concatenation of n disks is less reliable than n individual disks.
>
> David S.
>
>

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