Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030291AbWHXFOY (ORCPT ); Thu, 24 Aug 2006 01:14:24 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030293AbWHXFOY (ORCPT ); Thu, 24 Aug 2006 01:14:24 -0400 Received: from mserv4.uoregon.edu ([128.223.142.54]:22176 "EHLO smtp.uoregon.edu") by vger.kernel.org with ESMTP id S1030291AbWHXFOY (ORCPT ); Thu, 24 Aug 2006 01:14:24 -0400 Message-ID: <44ED358D.30602@uoregon.edu> Date: Wed, 23 Aug 2006 22:13:49 -0700 From: Joel Jaeggli User-Agent: Thunderbird 1.5.0.5 (Windows/20060719) MIME-Version: 1.0 To: Marc Perkel CC: Tejun Heo , Andre Tomt , linux-kernel@vger.kernel.org Subject: Re: Hardware vs. Software Raid Speed References: <44EBFB3E.8070905@perkel.com> <44EC02FD.7050207@tomt.net> <44EC94A9.4010903@gmail.com> <44EC9699.3040001@perkel.com> In-Reply-To: <44EC9699.3040001@perkel.com> X-Enigmail-Version: 0.94.1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2062 Lines: 51 Marc Perkel wrote: > > > Tejun Heo wrote: >> Andre Tomt wrote: >>> Marc Perkel wrote: >>>> Running Linux on an AMD AM2 nVidia chip ser that supports Raid 0 >>>> striping on the motherboard. Just wondering if hardware raid (SATA2) >> >> SATA2 has nothing to do with hardware RAID. >> >>>> is going to be faster that software raid and why? >>> >>> Beeing a consumer type board (AM2), the "raid on the motherboard" is >>> in 99.999% of the cases just software raid implemented in their >>> Windows drivers, a bootup setup screen plus some BIOS magic to get >>> the OS booting. >> >> And, yeah, they're all software RAID. Also, there isn't much to be >> gained from making RAID0/1 hardware. The software overhead isn't that >> big. For RAID5, having XOR done in hardware helps. >> > > Thanks - I suspected that Raid 0 didn't gain anything in hardware unless > they provided additional buffering or something but I just thought I'd > ask in case there was something I was overlooking. A hardware raid controller can buy you a battery backed write cache, so there are potentially some performance/safety benefits potentially. We have a mix of software raid and 3ware based hardware raid subsystems. For the applications we support, in general I can say that performance was not the discriminating reason to choose one over the other. > - > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ -- ------------------------------------------------------------------------ Joel Jaeggli Unix Consulting joelja@uoregon.edu GPG Key Fingerprint: 5C6E 0104 BAF0 40B0 5BD3 C38B F000 35AB B67F 56B2 - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/