Re: Raid and ORACLE

In article <etkr1tkdrf843vuid4emti2v331cqd5kb2_at_4ax.com>, kremovethisspamthingthomas_at_gfsiinc.com says...
> wtf? RAID 1, for redo is only expensive, but it effectively protect
> your redo from disk failure (RAID 1 is mirroring) - writes are not
> bad, and an reads can be satisfied from either mirror. Soooo, I don't
> see the big issue with RAID 1, especially since disk is cheap. (you
> should sitll of course do multiple sets - which ends up costing more
> in disk).
>
> OTOH, you get better performance doing RAID 0 (striping) for redo,
> and having multiple redo sets.
>
> But fired, eventually, why?
>
>
> On Thu, 23 Nov 2000 11:55:02 -0600, "Jim DeCicco"
> <decj1_at_interaccess.com> wrote:
>
> >I'd say that using Raid 1 would be closer to the optimal solution than it is
> >to the worst solution.
> >
> >Jim
> >
> >>
> >> Using RAID1 for redo log files should be just enough for you and your unix
> >> admin to get fired, eventually.
> >> --
> >> Michael O'Neill
> >> mjoneill_at_email.com
> >>

But Raid 0 offers absolutely no fault tolerance. The entire stripeset dies with the failure of a single disk. Not exactly where I would wish to put my redo logs or anything else I like. It is great for sort disks and tempfiles. Things that do not have to be backed up.

My redos live on a striped mirror set. A striped mirror set is several mirrored disks which are then striped. You can lose one disk in each of the mirrorsets and still have a stripe set. Given that the costs of disks is so cheap there is no reason not to do this. ( When I first started in this business 1 gig was $50,000 plus controllers and cables)

Liz Received on Tue Nov 28 2000 - 08:21:18 CST