From owner-freebsd-performance@FreeBSD.ORG Fri Feb 20 11:28:01 2004 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 B41C016A4CE for ; Fri, 20 Feb 2004 11:28:01 -0800 (PST) Received: from smtpout.mac.com (A17-250-248-89.apple.com [17.250.248.89]) by mx1.FreeBSD.org (Postfix) with ESMTP id 93D7443D1F for ; Fri, 20 Feb 2004 11:28:01 -0800 (PST) (envelope-from cswiger@mac.com) Received: from mac.com (smtpin07-en2 [10.13.10.152]) by smtpout.mac.com (Xserve/MantshX 2.0) with ESMTP id i1KJRZMq017645; Fri, 20 Feb 2004 11:27:37 -0800 (PST) Received: from [10.1.1.193] ([199.103.21.225]) (authenticated bits=0) by mac.com (Xserve/smtpin07/MantshX 3.0) with ESMTP id i1KJRXVN020336; Fri, 20 Feb 2004 11:27:34 -0800 (PST) In-Reply-To: <200402201147.03606@misha-mx.virtual-estates.net> References: <200402181729.06202@misha-mx.virtual-estates.net> <20040220072258.GA17579@VARK.homeunix.com> <200402201147.03606@misha-mx.virtual-estates.net> Mime-Version: 1.0 (Apple Message framework v612) Content-Type: text/plain; charset=US-ASCII; format=flowed Message-Id: Content-Transfer-Encoding: 7bit From: Charles Swiger Date: Fri, 20 Feb 2004 14:27:33 -0500 To: mi+mx@aldan.algebra.com X-Mailer: Apple Mail (2.612) cc: performance@FreeBSD.ORG Subject: Re: strange performance dip shown by iozone 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: Fri, 20 Feb 2004 19:28:01 -0000 On Feb 20, 2004, at 11:47 AM, mi+mx@aldan.algebra.com wrote: > Also, is the RAID5 writing speed supposed to be _so much_ worse, than > that of a single disk? it's normal for RAID-5 write performance to be slower than that of a bare drive. RAID filesystems involve tradeoffs between cost, performance, and reliability. RAID-5 maximizes cost and reliability at the expense of performance.... -- -Chuck