From owner-freebsd-questions Thu May 17 17:36:44 2001 Delivered-To: freebsd-questions@freebsd.org Received: from lotl.clari.net.au (lotl.clari.net.au [203.26.127.210]) by hub.freebsd.org (Postfix) with ESMTP id F363737B422 for ; Thu, 17 May 2001 17:36:38 -0700 (PDT) (envelope-from stephen@clari.net.au) Received: from theforce.clari.net.au (theforce.clari.net.au [203.8.14.120]) by lotl.clari.net.au (8.9.3/8.9.1) with ESMTP id KAA42761; Fri, 18 May 2001 10:35:36 +1000 (EST) (envelope-from stephen@clari.net.au) Message-ID: X-Mailer: XFMail 1.4.0 on FreeBSD X-Priority: 3 (Normal) Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 8bit MIME-Version: 1.0 In-Reply-To: <20010517011226.A4473@blazingdot.com> Date: Fri, 18 May 2001 10:39:33 +1000 (EST) Organization: ClariNET Internet Solutions From: Stephen Cimarelli To: Marcus Reid Subject: Re: Raid (BEST PERFORMANCE) Cc: Gabriel Ambuehl Cc: Gabriel Ambuehl , Jonathan Fortin , questions@FreeBSD.ORG, Greg Lehey Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk List-ID: X-Loop: FreeBSD.ORG Raid levels has seen by Mylex Level 0+1 Combines Daid 0 striping and Raid1 mirroring Level 10 Combines raid0 striping and Raid 1 mirroring spanned across multiple drive groups level 30 Combines Raid 0 and raid 3 across multiple drive groups Level 50 Combines Raid 0 and raid 5 across multiple drive groups is there some offical body that decided on what level 10,30,50 are, or do companys make up there own On 17-May-01 Marcus Reid wrote: > On Thu, May 17, 2001 at 04:50:26PM +0930, Greg Lehey wrote: >> On Wednesday, 16 May 2001 at 22:07:48 -0700, Marcus Reid wrote: >> > On Tue, May 08, 2001 at 06:22:26PM +0200, Gabriel Ambuehl wrote: >> >> >> >> Hello Jonathan, >> >> Monday, May 07, 2001, 7:08:48 PM, you wrote: >> >>> Best Performance Raid is a raid 0+1 setup. >> >>> For example, you got 4 20gb harddrives. >> >>> You create 2 strips of 2hds eachs, and you mirror them. >> >>> It will have redundancy and the speed will be as fast as a normal >> >> disk. It's >> >>> basically a Raid-1 setup with 2 hard drives per strip instead of one >> >> to >> >>> counter write performance hits. >> >> Some vendors like to call this RAID 10 (hmm. 1+0=10? only if those are >> >> strings...). >> > >> > If I'm not mistaken, there's a difference between 0+1 and 10: one is >> > striped and then mirrored, the other is mirrored and then striped. It's >> > supposed to have some bearing on performance, 0+1 being the faster one. >> >> I've heard people make this kind of claim. I can't understand what >> the difference is supposed to be. Can you justify it? > > It's something that I read on the qmail list; people were talking about > the best RAID scheme to use for a very high-volume mail server. I don't > have anything to offer from personal experience. I'm assembling a new mail > machine very soon and have to select which level of RAID to use, so I'd > be interested to hear if there's any truth behind it. > > Marcus > > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-questions" in the body of the message ---------------------------------- E-Mail: Stephen Cimarelli Date: 18-May-01 Time: 10:26:23 ClariNet Internet Solutions +61 3 9486 0811 www.clari.net.au ---------------------------------- To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message