From owner-freebsd-current@FreeBSD.ORG Tue Oct 19 20:18:19 2004 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 4446316A4CE for ; Tue, 19 Oct 2004 20:18:19 +0000 (GMT) Received: from CPE000103d44c07-CM000f9f7ae88c.cpe.net.cable.rogers.com (CPE000103d44c07-CM000f9f7ae88c.cpe.net.cable.rogers.com [69.193.222.195]) by mx1.FreeBSD.org (Postfix) with ESMTP id 42DF043D3F for ; Tue, 19 Oct 2004 20:18:18 +0000 (GMT) (envelope-from mikej@rogers.com) Received: from 192.168.0.1 (localhost [127.0.0.1]) with ESMTP id 31F3A29542A; Tue, 19 Oct 2004 16:18:12 -0400 (EDT) Received: from 192.168.0.188 (SquirrelMail authenticated user mikej); by 192.168.0.1 with HTTP; Tue, 19 Oct 2004 16:18:12 -0400 (EDT) Message-ID: <4259.192.168.0.188.1098217092.squirrel@192.168.0.188> In-Reply-To: <20041019200908.GA655@frontfree.net> References: <20041015190638.C5A0E5D04@ptavv.es.net> <41715E7F.7060509@ng.fadesa.es> <20041018100045.f8koww0skcco0woo@www.sweetdreamsracing.biz> <4173D66F.6010200@DeepCore.dk> <4173F2E9.7010407@ng.fadesa.es> <417406E3.9010706@DeepCore.dk> <4174FD04.8040000@ng.fadesa.es> <20041019104525.ikgw8kcw8sw480os@www.sweetdreamsracing.biz> <4129.192.168.0.188.1098211592.squirrel@192.168.0.188> <20041019200908.GA655@frontfree.net> Date: Tue, 19 Oct 2004 16:18:12 -0400 (EDT) From: "Mike Jakubik" To: "Xin LI" User-Agent: SquirrelMail/1.4.3a X-Mailer: SquirrelMail/1.4.3a MIME-Version: 1.0 Content-Type: text/plain;charset=iso-8859-1 Content-Transfer-Encoding: 8bit X-Priority: 3 (Normal) Importance: Normal X-wettoast-MailScanner-Information: Please contact the ISP for more information X-wettoast-MailScanner: Found to be clean X-MailScanner-From: mikej@rogers.com cc: freebsd-current@freebsd.org Subject: Re: FreeBSD 5.3b7and poor ata performance X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 19 Oct 2004 20:18:19 -0000 Xin LI said: > Hi, Mike, > > On Tue, Oct 19, 2004 at 02:46:32PM -0400, Mike Jakubik wrote: >> Out of curiosity, i ran this on one of our production servers, which >> runs >> on a dual Xeon MB, with SCSI raid-10 setup, and to my surprise here are >> the results: >> >> CPU: Intel(R) Xeon(TM) CPU 2.80GHz (2799.22-MHz 686-class CPU) >> real memory = 2146959360 (2047 MB) >> avail memory = 2099650560 (2002 MB) >> FreeBSD/SMP: Multiprocessor System Detected: 2 CPUs >> >> da0 at asr0 bus 0 target 0 lun 0 >> da0: Fixed Direct Access SCSI-2 device >> >> FreeBSD 5.3-BETA4 #0: Sun Sep 12 13:09:43 EDT 2004 >> >> (Custom kernel, no debugging) >> >> # dd if=/dev/da0 of=/dev/null bs=1m count=200 >> 200+0 records in >> 200+0 records out >> 209715200 bytes transferred in 6.225309 secs (33687517 bytes/sec) >> >> Why is a SCSI raid-10 system slower than a plain IDE disk? Something is >> wrong here. > > Unfortunatelly I can reproduce similiar problem when using Ultra320 under > mpt(4) and a version of Adaptec's SCSI card (maybe aic, or something else, > which I have to go to my office to find out). Additionally the problem is > not FreeBSD specific, with a Linux installation, it shows poor performance > too. (No RAID configuration, though). > > I found that block size does influence performance greatly. With a block > size of 131072 I got peak read performance at about 70MB/s, but that's > all. > I did not have the necessary knowledge at the time I have did the test > last > month, so I got only the result and thought that I have made something > wrong and hoped someone to correct me with no luck :-( Hrm, i tried your block size, and the performance is even worse: # dd if=/dev/da0 of=/dev/null bs=131072 count=2000 2000+0 records in 2000+0 records out 262144000 bytes transferred in 8.688651 secs (30170852 bytes/sec)