From owner-freebsd-testing@FreeBSD.ORG Sun Aug 17 08:36:17 2008 Return-Path: Delivered-To: freebsd-testing@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id D3E431065673 for ; Sun, 17 Aug 2008 08:36:17 +0000 (UTC) (envelope-from won.derick@yahoo.com) Received: from n4a.bullet.mail.ac4.yahoo.com (n4a.bullet.mail.ac4.yahoo.com [76.13.13.67]) by mx1.freebsd.org (Postfix) with SMTP id 833CA8FC17 for ; Sun, 17 Aug 2008 08:36:17 +0000 (UTC) (envelope-from won.derick@yahoo.com) Received: from [76.13.13.25] by n4.bullet.mail.ac4.yahoo.com with NNFMP; 17 Aug 2008 08:36:16 -0000 Received: from [76.13.10.166] by t4.bullet.mail.ac4.yahoo.com with NNFMP; 17 Aug 2008 08:36:16 -0000 Received: from [127.0.0.1] by omp107.mail.ac4.yahoo.com with NNFMP; 17 Aug 2008 08:36:16 -0000 X-Yahoo-Newman-Property: ymail-3 X-Yahoo-Newman-Id: 836154.14086.bm@omp107.mail.ac4.yahoo.com Received: (qmail 97698 invoked by uid 60001); 17 Aug 2008 08:36:16 -0000 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com; h=Received:X-Mailer:Date:From:Subject:To:Cc:MIME-Version:Content-Type:Message-ID; b=VBdIzp1V02/aJo73kcQT3A8ZD7FAJpYdXm7jOAWvLC0SGjQn8g8ZDc+qE/T6BHLEDrY3Kqn0U1f0UKaqr2ROsdrTzuTDMwAi7KfdHTa13Q4SlkQxzNSfiBgSSeaiyQxYg5ipvjRrD9SM7KtHsalddPlpLXw+G6T54APgSpLfCCI=; Received: from [58.71.34.137] by web45813.mail.sp1.yahoo.com via HTTP; Sun, 17 Aug 2008 01:36:15 PDT X-Mailer: YahooMailRC/1042.48 YahooMailWebService/0.7.218 Date: Sun, 17 Aug 2008 01:36:15 -0700 (PDT) From: Won De Erick To: Chris Elsworth MIME-Version: 1.0 Message-ID: <117484.97387.qm@web45813.mail.sp1.yahoo.com> Content-Type: text/plain; charset=us-ascii X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Cc: freebsd-testing@freebsd.org, Jeremy Chadwick , freebsd-performance@freebsd.org, freebsd-hardware@freebsd.org Subject: Re: CPU Utilization on IBM x3755 X-BeenThere: freebsd-testing@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Performance and Stability Tests List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 17 Aug 2008 08:36:18 -0000 On Sat, Aug 16, 2008 at 01:18:18AM -0700, Won De Erick wrote: >> >Regarding why you're adding up all the individual process statistics: I >> >can imagine they would vary a slight bit, but I cannot explain a 7% >> >variance. Someone with more knowledge will have to assist there. >> >> Though the header could be conclusive, I should want the specific processes (or threads). >> And come up with a list of breakdowns, like: >> >> Then match this by adding up all individual processes statistics. And if I couldn't match, at least I could tell some factors that cause variance. > >At the bottom of man top, reformatted for email width: > > As with ps(1), things can change while top is collecting > information for an update. The picture it gives is only > a close approximation to reality. > >Could this explain the variations you are seeing? top never gives you >an accurate snapshot of what the system is doing at any one instant in >time, afaik. >-- >Chris I'm aware with this limitation as displayed using man top. But when I ran top -SI, I only got 8 processes out of 12 processes [actively] running as displayed on the header making it far from reality. I did this several times, restarting the machine, bootstrapping, etc, but I got same result. I don't know what kernel threads are causing top -S to display the command as "idle: cpu0", "idle : cpu1", ... "idle:cpu7". Though Jeremy had mentioned them as simply kernel threads (due to lack of term), I should at least dig deeper on this matter and be able to specifically classify them.