From owner-freebsd-performance@FreeBSD.ORG Wed Oct 27 11:25:05 2010 Return-Path: Delivered-To: freebsd-performance@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 944421065693 for ; Wed, 27 Oct 2010 11:25:05 +0000 (UTC) (envelope-from gofp-freebsd-performance@m.gmane.org) Received: from lo.gmane.org (lo.gmane.org [80.91.229.12]) by mx1.freebsd.org (Postfix) with ESMTP id 44DD38FC13 for ; Wed, 27 Oct 2010 11:25:05 +0000 (UTC) Received: from list by lo.gmane.org with local (Exim 4.69) (envelope-from ) id 1PB47q-0003DR-4R for freebsd-performance@freebsd.org; Wed, 27 Oct 2010 13:25:02 +0200 Received: from lara.cc.fer.hr ([161.53.72.113]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Wed, 27 Oct 2010 13:25:02 +0200 Received: from ivoras by lara.cc.fer.hr with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Wed, 27 Oct 2010 13:25:02 +0200 X-Injected-Via-Gmane: http://gmane.org/ To: freebsd-performance@freebsd.org From: Ivan Voras Date: Wed, 27 Oct 2010 13:24:54 +0200 Lines: 13 Message-ID: References: <20101026121352.GC2262@albert.catwhisker.org> <20101020174854.GZ21226@albert.catwhisker.org> <20101021215330.GA86224@dan.emsphone.com> <20101021224237.GG52404@albert.catwhisker.org> <4CC6C396.1010905@freebsd.org> <20101026174501.GH2262@albert.catwhisker.org> <20101027105506.GD9443@albert.catwhisker.org> <20101027111904.GF9443@albert.catwhisker.org> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Complaints-To: usenet@dough.gmane.org X-Gmane-NNTP-Posting-Host: lara.cc.fer.hr User-Agent: Mozilla/5.0 (X11; U; FreeBSD amd64; en-US; rv:1.9.1.12) Gecko/20101018 Thunderbird/3.0.8 In-Reply-To: <20101027111904.GF9443@albert.catwhisker.org> X-Enigmail-Version: 1.0.1 Subject: Re: Possible evidence of performance regression for 8.1-S (vs. 7.1) X-BeenThere: freebsd-performance@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Performance/tuning List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 27 Oct 2010 11:25:05 -0000 On 10/27/10 13:19, David Wolfskill wrote: >> note 2x drop in performance between outer and inner tracks. > > OK, but I'm not sure how that's likely to work for a multi-spindle RAID > 0 group.... Unless the RAID controller is trying to be overly smart (i.e. plays with fire) by somehow alternating stripe positions on drives, exactly the same as with single drives - stripe 0 on drive one will be logically joined with stripe 0 on the other drive, etc.