From owner-freebsd-performance@FreeBSD.ORG Mon May 2 14:37:40 2005 Return-Path: Delivered-To: freebsd-performance@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id E229816A4CF for ; Mon, 2 May 2005 14:37:40 +0000 (GMT) Received: from critter.freebsd.dk (0x535c0e2a.sgnxx1.adsl-dhcp.tele.dk [83.92.14.42]) by mx1.FreeBSD.org (Postfix) with ESMTP id 04A0C43D31 for ; Mon, 2 May 2005 14:37:40 +0000 (GMT) (envelope-from phk@critter.freebsd.dk) Received: from critter.freebsd.dk (localhost [127.0.0.1]) by critter.freebsd.dk (8.13.3/8.13.3) with ESMTP id j42EbaCf018195; Mon, 2 May 2005 16:37:36 +0200 (CEST) (envelope-from phk@critter.freebsd.dk) To: Eric Anderson From: "Poul-Henning Kamp" In-Reply-To: Your message of "Mon, 02 May 2005 09:28:22 CDT." <42763906.1040202@centtech.com> Date: Mon, 02 May 2005 16:37:36 +0200 Message-ID: <18194.1115044656@critter.freebsd.dk> Sender: phk@critter.freebsd.dk cc: freebsd-performance@freebsd.org cc: Allen cc: Steven Hartland Subject: Re: Very low disk performance on 5.x X-BeenThere: freebsd-performance@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Performance/tuning List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 02 May 2005 14:37:41 -0000 In message <42763906.1040202@centtech.com>, Eric Anderson writes: >> In message <6.2.1.2.2.20050502094757.037077f0@mail.rfnj.org>, Allen writes: >> >> I just want to add: This is why I really would love for us to have >> a real RAID3 implemetation. >> >> RAID3 is not commercially viable because windows cannot use non-512 >> byte sectors. >> >> We can. >> >> RAID3 would scream for us. > >What about disk arrays that support RAID3? Would work for me, but most of them are dumbed down when they do RAID3: they have to hard format the disks to 128 byte sector sizes and similar madness in order to support 512 bytes sectors on the RAID3 volume. Some of them use 512 byte sector disks and internal sectorsizes of N*512 bytes and use their battery-backed cache to pretend to have 512 bytes logical sectorsize. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk@FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence.