From owner-freebsd-questions@FreeBSD.ORG Tue Jan 6 09:56:58 2004 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 6BBAC16A4CE for ; Tue, 6 Jan 2004 09:56:58 -0800 (PST) Received: from dan.emsphone.com (dan.emsphone.com [199.67.51.101]) by mx1.FreeBSD.org (Postfix) with ESMTP id CFCFA43D49 for ; Tue, 6 Jan 2004 09:56:52 -0800 (PST) (envelope-from dan@dan.emsphone.com) Received: (from dan@localhost) by dan.emsphone.com (8.12.10/8.12.10) id i06HukA3081270; Tue, 6 Jan 2004 11:56:46 -0600 (CST) (envelope-from dan) Date: Tue, 6 Jan 2004 11:56:46 -0600 From: Dan Nelson To: Mike Maltese Message-ID: <20040106175645.GE38169@dan.emsphone.com> References: <000201c3d461$eea71770$0301a8c0@office.cpainc.net> <012d01c3d47d$40fe8b50$f4f0a8c0@pcmedx.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <012d01c3d47d$40fe8b50$f4f0a8c0@pcmedx.com> X-OS: FreeBSD 5.2-CURRENT X-message-flag: Outlook Error User-Agent: Mutt/1.5.5.1i cc: Derek Marcotte cc: questions@freebsd.org Subject: Re: Poor SCSI disk preformance X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 06 Jan 2004 17:56:58 -0000 In the last episode (Jan 06), Mike Maltese said: > > I also had (meaning it is not currently attached) a different SCSI > > drive attached on the bus, with the same results. Has anyone any > > tips for this from a FreeBSD point of view? > > I wouldn't say that dd is the greatest benchmarking tool. You may > want to try benchmarks/rawio. Also, try monitoring diffferent types > of transfers to and from another physical disk with iostat. I'm not > sure what your speed expectations are, but you're running a 7200 RPM > Ultra Wide disk on an Ultra Wide host adapter; not exactly the > fastest SCSI technology. It should go faster than 5MB/sec, though. Seagate's specs say that drive should do 14MB/sec max. UW's top speed is 40MB/sec, so there shouldn't be any bottlenecks. -- Dan Nelson dnelson@allantgroup.com