From owner-freebsd-performance@FreeBSD.ORG Wed Oct 27 11:06:27 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 A6532106566B for ; Wed, 27 Oct 2010 11:06:27 +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 59ACB8FC08 for ; Wed, 27 Oct 2010 11:06:27 +0000 (UTC) Received: from list by lo.gmane.org with local (Exim 4.69) (envelope-from ) id 1PB3po-0002SP-Iw for freebsd-performance@freebsd.org; Wed, 27 Oct 2010 13:06:24 +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 13:06:24 +0200 Received: from ivoras by lara.cc.fer.hr with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Wed, 27 Oct 2010 13:06:24 +0200 X-Injected-Via-Gmane: http://gmane.org/ To: freebsd-performance@freebsd.org From: Ivan Voras Date: Wed, 27 Oct 2010 13:06:18 +0200 Lines: 22 Message-ID: References: <20101021224237.GG52404@albert.catwhisker.org> <4CC6C396.1010905@freebsd.org> <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> 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: <20101027105506.GD9443@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 11:06:27 -0000 On 10/27/10 12:55, David Wolfskill wrote: > That *is* a problem, as I cannot justify a migration to a branch > of FreeBSD that imposes about a 23% penalty in elapsed time on this > workload. I want folks at work to have more reason to want to use > (newer branches of) FreeBSD, not less. That is understandable, I'm only saying that given the symptoms - some "waiting" that is not accounted in system or user time and with NFS mostly ruled out (maybe a better test would be to extract a local tarball *to* the NFS server), the next suspect is the disk system. In case you never tried "diskinfo -vt", its results look like this: outside: 102400 kbytes in 1.222998 sec = 83729 kbytes/sec middle: 102400 kbytes in 1.448580 sec = 70690 kbytes/sec inside: 102400 kbytes in 2.531694 sec = 40447 kbytes/sec note 2x drop in performance between outer and inner tracks. It's not certain, especially since your results are repeatable and you always use exactly the same file system, but it's possible. Have you tried the sysctls I've posted?