From owner-freebsd-hardware@FreeBSD.ORG Thu Apr 12 16:42:13 2007 Return-Path: X-Original-To: freebsd-hardware@freebsd.org Delivered-To: freebsd-hardware@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 9B71616A402 for ; Thu, 12 Apr 2007 16:42:13 +0000 (UTC) (envelope-from biogary@gmail.com) Received: from an-out-0708.google.com (an-out-0708.google.com [209.85.132.242]) by mx1.freebsd.org (Postfix) with ESMTP id 5303C13C45B for ; Thu, 12 Apr 2007 16:42:13 +0000 (UTC) (envelope-from biogary@gmail.com) Received: by an-out-0708.google.com with SMTP id c24so646849ana for ; Thu, 12 Apr 2007 09:42:12 -0700 (PDT) DKIM-Signature: a=rsa-sha1; c=relaxed/relaxed; d=gmail.com; s=beta; h=domainkey-signature:received:received:message-id:date:from:reply-to:to:subject:cc:in-reply-to:mime-version:content-type:references; b=e7WLASMsO4LxTbp6aFxieYrpwd2eog56Dev9ZpMTIfcicKa5d2/owVtAg0sTStwDsivM0vBj9dXLUJhXkEbIXaE/0dRdxol3CuTncPXoCiz3BeATjWs7qjOdKU4bmwh5qKGzvx8pcKTivgCdAygBy0WMOqxDw99AyugZegvZP0s= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:reply-to:to:subject:cc:in-reply-to:mime-version:content-type:references; b=Sl3fxm6Je1/AOS1Sp9u5z0I021buPVKHl/RVzFiYa8Si5tA/D4zNlGYPUCBkiG1+B0aruQF/7BRIWN7SJODBxNVDo4+/kJWyR+CZMJ9rFvVg0mynjOqziyU5NPvgCSeDXHJr0/0TgSygbMI9JSkLmvk3G3ZBkxyVal4zQzyXR6Y= Received: by 10.100.166.14 with SMTP id o14mr1544536ane.1176396132354; Thu, 12 Apr 2007 09:42:12 -0700 (PDT) Received: by 10.100.31.17 with HTTP; Thu, 12 Apr 2007 09:42:11 -0700 (PDT) Message-ID: <224a745a0704120942i19c42927o9826b0343938d093@mail.gmail.com> Date: Fri, 13 Apr 2007 00:42:11 +0800 From: "Tzu-Hua Wang" To: "Ivan Voras" In-Reply-To: MIME-Version: 1.0 References: <224a745a0704092137h67f5f463w6b355535a6b8415f@mail.gmail.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Cc: freebsd-hardware@freebsd.org Subject: Re: the performance of SAS is not better than SCSI in FreeBSD, WHY? X-BeenThere: freebsd-hardware@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: thwang@mail.nhcue.edu.tw List-Id: General discussion of FreeBSD hardware List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 12 Apr 2007 16:42:13 -0000 Hi: When using 'dmesg' command, it shows that da0 at ciss0 bus 0 target 0 lun 0 da0: Fixed Direct Access SCSI-0 device da0: 135.168MB/s transfers da0: 419946MB (860051248 512 byte sectors: 255H 32S/T 65535C) Oh, my goodness. My SAS HD is only the SCSI-0 device. I think this is the major reason. Why? Can you give me a hand? Problem of configuration on the RAID Card? I am sorry, I am really new to the RAID system. Thanks 2007/4/11, Ivan Voras : > > Tzu-Hua Wang wrote: > > > Generally, the performace of SAS in FreeBSD is far worse than SCSI in > > FreeBSD. > > Is it normal? How can I do to improve the performance of SAS HD in > FreeBSD? > > There's a huge number of possible reasons - unless you're testing the > same controller (I think there exist SAS+SCSI controllers, I might be > wrong), you can't conclude that the SAS interface is less supported. > > For what it's worth, I've got approximately the same numbers on DL380 > G5, but I've attributed them to 2.5" small form factor drives. > > 2x 2.5" 10k RPM, CISS hw RAID1 2x 3.5", 7.5k RPM, soft RAID1 > Full stroke 3.863 ms 5.942 ms > Half stroke 3.929 ms 6.186 ms > Quarter stroke 3.998 ms 5.700 ms > Short forward 3.889 ms 4.060 ms > Short backward 4.715 ms 4.748 ms > Seqential outer 1.011 ms 0.167 ms > Sequential inner 1.013 ms 0.177 ms > Read transfer, outside 43.6 MB/s 61.2 MB/s > Read transfer, middle 38.8 MB/s 54.8 MB/s > Read transfer, inside 32.8 MB/s 34.9 MB/s > > The 3.5" drives were SATA in a different machine (Dell's). It might be > that the CISS driver is unreasonably slow, which is kind of possible > given the suspicious lower bound of about 1 ms in seeks. Maybe something > is throttling the I/O rate? > > >