From owner-freebsd-current@FreeBSD.ORG Mon Dec 6 06:12:31 2010 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 2578A106566B; Mon, 6 Dec 2010 06:12:31 +0000 (UTC) (envelope-from sgk@troutmask.apl.washington.edu) Received: from troutmask.apl.washington.edu (troutmask.apl.washington.edu [128.208.78.105]) by mx1.freebsd.org (Postfix) with ESMTP id F09718FC19; Mon, 6 Dec 2010 06:12:30 +0000 (UTC) Received: from troutmask.apl.washington.edu (localhost.apl.washington.edu [127.0.0.1]) by troutmask.apl.washington.edu (8.14.4/8.14.4) with ESMTP id oB66CUDv069505; Sun, 5 Dec 2010 22:12:30 -0800 (PST) (envelope-from sgk@troutmask.apl.washington.edu) Received: (from sgk@localhost) by troutmask.apl.washington.edu (8.14.4/8.14.4/Submit) id oB66CUd7069504; Sun, 5 Dec 2010 22:12:30 -0800 (PST) (envelope-from sgk) Date: Sun, 5 Dec 2010 22:12:30 -0800 From: Steve Kargl To: Julian Elischer Message-ID: <20101206061230.GA69477@troutmask.apl.washington.edu> References: <20101205231829.GA68156@troutmask.apl.washington.edu> <4CFC27A0.8000406@freebsd.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4CFC27A0.8000406@freebsd.org> User-Agent: Mutt/1.4.2.3i Cc: freebsd-current@freebsd.org Subject: Re: Process accounting/timing has broken recently X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 06 Dec 2010 06:12:31 -0000 On Sun, Dec 05, 2010 at 04:00:32PM -0800, Julian Elischer wrote: > On 12/5/10 3:18 PM, Steve Kargl wrote: > >Sometime in the last 7-10 days, some one made a > >change that has broken process accounting/timing. > > > >laptop:kargl[42] foreach i ( 0 1 2 3 4 5 6 7 8 9 ) > >foreach? time ./testf > >foreach? end > >Max ULP: 0.501607 for x in [-18.000000:88.709999] with dx = 1.067100e-04 > > 69.55 real 38.39 user 30.94 sys > >Max ULP: 0.501607 for x in [-18.000000:88.709999] with dx = 1.067100e-04 > > 68.82 real 40.95 user 27.60 sys > >Max ULP: 0.501607 for x in [-18.000000:88.709999] with dx = 1.067100e-04 > > 69.14 real 38.90 user 30.02 sys > >Max ULP: 0.501607 for x in [-18.000000:88.709999] with dx = 1.067100e-04 > > 68.79 real 40.59 user 27.99 sys > >Max ULP: 0.501607 for x in [-18.000000:88.709999] with dx = 1.067100e-04 > > 68.93 real 39.76 user 28.96 sys > >Max ULP: 0.501607 for x in [-18.000000:88.709999] with dx = 1.067100e-04 > > 68.71 real 41.21 user 27.29 sys > >Max ULP: 0.501607 for x in [-18.000000:88.709999] with dx = 1.067100e-04 > > 69.05 real 39.68 user 29.15 sys > >Max ULP: 0.501607 for x in [-18.000000:88.709999] with dx = 1.067100e-04 > > 68.99 real 39.98 user 28.80 sys > >Max ULP: 0.501607 for x in [-18.000000:88.709999] with dx = 1.067100e-04 > > 69.02 real 39.64 user 29.16 sys > >Max ULP: 0.501607 for x in [-18.000000:88.709999] with dx = 1.067100e-04 > > 69.38 real 37.49 user 31.67 sys > > > >testf is a numerically intensive program that tests the > >accuracy of expf() in a tight loop. User time varies > >by ~3 seconds on my lightly loaded 2 GHz core2 duo processor. > >I'm fairly certain that the code does not suddenly grow/loose > >6 GFLOP of operations. > > > I know it's a lot to ask but it may be something that you can help > with if you > had the time to triangulate in on the change that did it.. > I presume that since you are an "old hand" you can check out sources > at different revisions.. I was hoping that someone (possibly the person responsible) would recognize the symptoms and recommend a revision or two to revert. Otherwise, doing a binary search will take some time in that it takes 4+ hours for a buildworld/kernel cycle on my laptop. -- Steve