From owner-freebsd-fs@FreeBSD.ORG Mon Jan 25 05:33:09 2010 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 0B4D31065692; Mon, 25 Jan 2010 05:33:09 +0000 (UTC) (envelope-from bfriesen@simple.dallas.tx.us) Received: from blade.simplesystems.org (blade.simplesystems.org [65.66.246.74]) by mx1.freebsd.org (Postfix) with ESMTP id BF0E48FC0A; Mon, 25 Jan 2010 05:33:08 +0000 (UTC) Received: from freddy.simplesystems.org (freddy.simplesystems.org [65.66.246.65]) by blade.simplesystems.org (8.13.8+Sun/8.13.8) with ESMTP id o0P5X7BA024156; Sun, 24 Jan 2010 23:33:07 -0600 (CST) Date: Sun, 24 Jan 2010 23:33:07 -0600 (CST) From: Bob Friesenhahn X-X-Sender: bfriesen@freddy.simplesystems.org To: Dan Naumov In-Reply-To: Message-ID: References: <883b2dc51001240905r4cfbf830i3b9b400969ac261b@mail.gmail.com> <1264368182.00211075.1264355402@10.7.7.3> <4B5CC167.5010604@FreeBSD.org> User-Agent: Alpine 2.01 (GSO 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.2 (blade.simplesystems.org [65.66.246.90]); Sun, 24 Jan 2010 23:33:07 -0600 (CST) Cc: freebsd-fs@freebsd.org, Alexander Motin , Jason Edwards , FreeBSD-STABLE Mailing List , freebsd-questions@freebsd.org Subject: Re: 8.0-RELEASE/amd64 - full ZFS install - low read and write disk performance X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 25 Jan 2010 05:33:09 -0000 On Mon, 25 Jan 2010, Dan Naumov wrote: > > I've checked with the manufacturer and it seems that the Sil3124 in > this NAS is indeed a PCI card. More info on the card in question is > available at http://green-pcs.co.uk/2009/01/28/tranquil-bbs2-those-pci-cards/ > I have the card described later on the page, the one with 4 SATA ports > and no eSATA. Alright, so it being PCI is probably a bottleneck in > some ways, but that still doesn't explain the performance THAT bad, > considering that same hardware, same disks, same disk controller push > over 65mb/s in both reads and writes in Win2008. And agian, I am > pretty sure that I've had "close to expected" results when I was The slow PCI bus and this card look like the bottleneck to me. Remember that your Win2008 tests were with just one disk, your zfs performance with just one disk was similar to Win2008, and your zfs performance with a mirror was just under 1/2 that. I don't think that your performance results are necessarily out of line for the hardware you are using. On an old Sun SPARC workstation with retrofitted 15K RPM drives on Ultra-160 SCSI channel, I see a zfs mirror write performance of 67,317KB/second and a read performance of 124,347KB/second. The drives themselves are capable of 100MB/second range performance. Similar to yourself, I see 1/2 the write performance due to bandwidth limitations. Bob -- Bob Friesenhahn bfriesen@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/ GraphicsMagick Maintainer, http://www.GraphicsMagick.org/