From owner-freebsd-stable Mon Mar 12 22:35:43 2001 Delivered-To: freebsd-stable@freebsd.org Received: from level3.dynacom.net (level3.dynacom.net [206.107.213.213]) by hub.freebsd.org (Postfix) with SMTP id 1E21237B71A for ; Mon, 12 Mar 2001 22:35:36 -0800 (PST) (envelope-from kstewart@urx.com) Received: (qmail 26306 invoked by uid 0); 13 Mar 2001 06:35:34 -0000 Received: from unknown (HELO urx.com) (206.159.132.160) by mail.urx.com with SMTP; 13 Mar 2001 06:35:34 -0000 Message-ID: <3AADBFB6.D0595C28@urx.com> Date: Mon, 12 Mar 2001 22:35:34 -0800 From: Kent Stewart Reply-To: kstewart@urx.com Organization: Dynacom X-Mailer: Mozilla 4.76 [en] (Windows NT 5.0; U) X-Accept-Language: en MIME-Version: 1.0 To: "Jeffrey J. Mountin" Cc: Jean-Marc Zucconi , freebsd-stable@FreeBSD.ORG Subject: Re: UDMA 33/UDMA 100 perfs References: <4.3.2.20010313002151.02d94c70@207.227.119.2> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-stable@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG "Jeffrey J. Mountin" wrote: > > At 07:29 PM 3/12/01 -0800, Jean-Marc Zucconi wrote: > >Is this the normal behavior expected? > > > >1) > >ata0-master: DMA limited to UDMA33, non-ATA66 compliant cable > >ad0: 19092MB [38792/16/63] at ata0-master using UDMA33 > ># dd if=/dev/ad0e of=/dev/null bs=1m count=1000 > >1048576000 bytes transferred in 49.445390 secs (21206750 bytes/sec) > > > >2) > >ad0: 19092MB [38792/16/63] at ata0-master UDMA100 > ># dd if=/dev/ad0e of=/dev/null bs=1m count=1000 > >1048576000 bytes transferred in 49.337278 secs (21253220 bytes/sec) > > > >I get the same performance in both cases. This is with a 4.3-BETA > >kernel. I have only one drive on the IDE bus. > > Just because the speed limit goes up doesn't mean your car will go faster. Especially since they only do this for 3ms at a time. This is what I read that the length of the time burst was. The only was I could get buildworld times down was to add 3 of the ATA-100's onto individual controllers and enable soft-updates. Kent > > To wit there are few drives that can exceed what UDMA33 can handle and only > then would the higher "speed limit" help. > > Jeff Mountin - jeff@mountin.net > Systems/Network Administrator > FreeBSD - the power to serve > > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-stable" in the body of the message -- Kent Stewart Richland, WA mailto:kbstew99@hotmail.com http://kstewart.urx.com/kstewart/index.html FreeBSD News http://daily.daemonnews.org/ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message