From owner-freebsd-questions@FreeBSD.ORG Fri May 30 08:22:17 2003 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 A886A37B401 for ; Fri, 30 May 2003 08:22:17 -0700 (PDT) Received: from pop016.verizon.net (pop016pub.verizon.net [206.46.170.173]) by mx1.FreeBSD.org (Postfix) with ESMTP id 9099543F3F for ; Fri, 30 May 2003 08:22:16 -0700 (PDT) (envelope-from cswiger@mac.com) Received: from mac.com ([129.44.60.214]) by pop016.verizon.net (InterMail vM.5.01.05.33 201-253-122-126-133-20030313) with ESMTP id <20030530152215.JJTO3199.pop016.verizon.net@mac.com>; Fri, 30 May 2003 10:22:15 -0500 Message-ID: <3ED77728.8080009@mac.com> Date: Fri, 30 May 2003 11:22:16 -0400 From: Chuck Swiger Organization: The Courts of Chaos User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.4b) Gecko/20030507 X-Accept-Language: en-us, en MIME-Version: 1.0 To: peo@intersonic.se References: <3ED72156.1070905@intersonic.se> <20030530101845.GG40976@wantadilla.lemis.com> <3ED74FF4.2010905@intersonic.se> In-Reply-To: <3ED74FF4.2010905@intersonic.se> X-Enigmail-Version: 0.75.0.0 X-Enigmail-Supports: pgp-inline, pgp-mime Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-Authentication-Info: Submitted using SMTP AUTH at pop016.verizon.net from [129.44.60.214] at Fri, 30 May 2003 10:22:15 -0500 cc: freebsd-questions@freebsd.org Subject: Re: Vinum performance 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: Fri, 30 May 2003 15:22:17 -0000 Per olof Ljungmark wrote: [ ... ] > The bottleneck is write performance, reading from the documentation this > is normally a weak point in Vinum/raid5 setups. It's not vinum; RAID-5 write performance is going to be relatively slow even with hardware parity/XOR support. > The volume will be used for storing temporary files with sizes in the > 1-4MB range, a few hundreds at a time. Reads are fine but writes a bit > slow. What ratio of reads to writes do you expect? > Copying 170 files total 319MB TO the Vinum volume takes about 2m45s. > Copying same files FROM the Vinum volume to another volume on a hardware > raid5 controller takes 43s. A 3-1 ratio in speeds for software RAID-5 versus hardware doesn't strike me as being very wrong.... > This machine is not in production yet so I can still make changes to the > configuration. The current block size is 16384 and the stripe size 419k. > I assume it would be a good idea to change that to for example 491,520? ...or try a few stripe sizes, such as 64K or 128K. -Chuck