Re: Slow restoration question - Mailing list pgsql-performance

From Mark Lewis
Subject Re: Slow restoration question
Date
Msg-id 1146595755.12053.111.camel@archimedes
Whole thread Raw
In response to Re: Slow restoration question  (Brendan Duddridge <brendan@clickspace.com>)
Responses Re: Slow restoration question
List pgsql-performance
They are not equivalent.  As I understand it, RAID 0+1 performs about
the same as RAID 10 when everything is working, but degrades much less
nicely in the presence of a single failed drive, and is more likely to
suffer catastrophic data loss if multiple drives fail.

-- Mark

On Tue, 2006-05-02 at 12:40 -0600, Brendan Duddridge wrote:
> Everyone here always says that RAID 5 isn't good for Postgres. We
> have an Apple Xserve RAID configured with RAID 5. We chose RAID 5
> because Apple said their Xserve RAID was "optimized" for RAID 5. Not
> sure if we made the right decision though. They give an option for
> formatting as RAID 0+1. Is that the same as RAID 10 that everyone
> talks about? Or is it the reverse?
>
> Thanks,
>
> ____________________________________________________________________
> Brendan Duddridge | CTO | 403-277-5591 x24 |  brendan@clickspace.com
>
> ClickSpace Interactive Inc.
> Suite L100, 239 - 10th Ave. SE
> Calgary, AB  T2G 0V9
>
> http://www.clickspace.com
>
> On May 2, 2006, at 11:16 AM, Jim C. Nasby wrote:
>
> > On Wed, Apr 26, 2006 at 05:14:41PM +0930, Eric Lam wrote:
> >> all dumpfiles total about 17Gb. It has been running for 50ish hrs
> >> and up
> >> to about the fourth file (5-6 ish Gb) and this is on a raid 5 server.
> >
> > RAID5 generally doesn't bode too well for performance; that could be
> > part of the issue.
> > --
> > Jim C. Nasby, Sr. Engineering Consultant      jnasby@pervasive.com
> > Pervasive Software      http://pervasive.com    work: 512-231-6117
> > vcard: http://jim.nasby.net/pervasive.vcf       cell: 512-569-9461
> >
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> >
> >                http://archives.postgresql.org
> >
>
>
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