Received: from localhost (maia-3.hub.org [200.46.204.184]) by postgresql.org (Postfix) with ESMTP id 723179FBDE0 for ; Wed, 30 May 2007 07:42:41 -0300 (ADT) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.184]) (amavisd-maia, port 10024) with ESMTP id 27731-06 for ; Wed, 30 May 2007 07:42:33 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey-1.7.4 Received: from tamriel.snowman.net (tamriel.snowman.net [72.66.115.51]) by postgresql.org (Postfix) with ESMTP id A00A89FBD9A for ; Wed, 30 May 2007 07:42:37 -0300 (ADT) Received: by tamriel.snowman.net (Postfix, from userid 1000) id 6E5A68419E; Wed, 30 May 2007 06:42:36 -0400 (EDT) Date: Wed, 30 May 2007 06:42:36 -0400 From: Stephen Frost To: Peter Childs Cc: pgsql-performance@postgresql.org Subject: Re: setting up raid10 with more than 4 drives Message-ID: <20070530104236.GW7531@tamriel.snowman.net> Mail-Followup-To: Peter Childs , pgsql-performance@postgresql.org References: <36e682920705292141k9aa038btb543d97cee0fa4a1@mail.gmail.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="ngiTnHdmUEG79yp6" Content-Disposition: inline In-Reply-To: X-Editor: Vim http://www.vim.org/ X-Info: http://www.snowman.net X-Operating-System: Linux/2.6.18-4-vserver-amd64 (x86_64) X-Uptime: 06:41:41 up 23 days, 6:54, 18 users, load average: 0.11, 0.21, 0.20 User-Agent: Mutt/1.5.13 (2006-08-11) X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200705/607 X-Sequence-Number: 24997 --ngiTnHdmUEG79yp6 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline * Peter Childs (peterachilds@gmail.com) wrote: > Good point, also if you had Raid 1 with 3 drives with some bit errors at > least you can take a vote on whats right. Where as if you only have 2 and > they disagree how do you know which is right other than pick one and hope... > But whatever it will be slower to keep in sync on a heavy write system. I'm not sure, but I don't think most RAID1 systems do reads against all drives and compare the results before returning it to the caller... I'd be curious if I'm wrong. Thanks, Stephen --ngiTnHdmUEG79yp6 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.6 (GNU/Linux) iD8DBQFGXVUcrzgMPqB3kigRAi/sAJ9K5vR2YrOac/4EM9NZcI0anCjOYACgidyX GuvMXTO/3D7vWRkAK/E6shw= =oQA1 -----END PGP SIGNATURE----- --ngiTnHdmUEG79yp6--