Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756570AbZIOIhn (ORCPT ); Tue, 15 Sep 2009 04:37:43 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753577AbZIOIhi (ORCPT ); Tue, 15 Sep 2009 04:37:38 -0400 Received: from mail.gmx.net ([213.165.64.20]:59536 "HELO mail.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1751641AbZIOIhg (ORCPT ); Tue, 15 Sep 2009 04:37:36 -0400 X-Authenticated: #14349625 X-Provags-ID: V01U2FsdGVkX1/5Lgo2JNf55mHlf3Ezi+IcRh/GLRhntdWHS6M7nG 7W0o/jzYl76Mx2 Subject: Re: Phoronix CFS vs BFS bencharks From: Mike Galbraith To: Willy Tarreau Cc: Marcin Letyns , Nikos Chantziaras , Ingo Molnar , Con Kolivas , linux-kernel@vger.kernel.org, Peter Zijlstra In-Reply-To: <20090914204905.GA28315@1wt.eu> References: <20090906205952.GA6516@elte.hu> <4AAE10E6.2050403@arcor.de> <1252928133.22740.37.camel@marge.simson.net> <1252942335.12986.58.camel@marge.simson.net> <20090914204905.GA28315@1wt.eu> Content-Type: text/plain Date: Tue, 15 Sep 2009 10:37:35 +0200 Message-Id: <1253003855.6628.63.camel@marge.simson.net> Mime-Version: 1.0 X-Mailer: Evolution 2.24.1.1 Content-Transfer-Encoding: 7bit X-Y-GMX-Trusted: 0 X-FuHaFi: 0.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5403 Lines: 139 On Mon, 2009-09-14 at 22:49 +0200, Willy Tarreau wrote: > On Mon, Sep 14, 2009 at 09:14:35PM +0200, Marcin Letyns wrote: > > 2009/9/14 Mike Galbraith > > > > > > On Mon, 2009-09-14 at 16:27 +0200, Marcin Letyns wrote: > > > > Hello, > > > > > > > > Disabling NEW_FAIR_SLEEPERS makes a lot of difference here in the > > > > Apache benchmark: > > > > > > > > 2.6.30.6-bfs: 7311.05 > > > > > > > > 2.6.30.6-cfs-fair_sl_disabled: 8249.17 > > > > > > > > 2.6.30.6-cfs-fair_sl_enabled: 4894.99 > > > > > > Wow. > > > > > > Some loads like wakeup preemption (mysql+oltp), and some hate it. This > > > load appears to REALLY hate it (as does volanomark, but that thing is > > > extremely overloaded). How many threads does that benchmark run > > > concurrently? > > > > >From the benchmark description: > > > > This is a test of ab, which is the Apache Benchmark program. This test > > profile measures how many requests per second a given system can > > sustain when carrying out 500,000 requests with 100 requests being > > carried out concurrently. > > Be careful not to run ab on the same machine as you run apache, otherwise > the numerous apache processes can limit ab's throughput. This is the same > reason as why I educate people so that they don't run a single-process > proxy in front of a multi-process/multi-thread web server. Apparently > it's not obvious to everyone. I turned on apache, and played with ab a bit, and yup, ab is a hog, so any fairness hurts it a badly. Ergo, running ab on the same box as apache suffers with CFS when NEW_FAIR_SLEEPERS are turned on. Issuing ab bandwidth to match it's 1:N pig nature brings throughput right back. (In all the comparison testing I've done, BFS favors hogs, and with NEW_FAIR_SLEEPERS turned off, so does CFS, though not as much.) Running apache on one core and ab on another (with shared cache tho), something went south with BFS. I would have expected it to be much closer (shrug). Some likely not very uninteresting numbers below. I wasted a lot more of my time generating them than anyone will downloading them :) ab -n 500000 -c 100 http://localhost/openSUSE.org.html 2.6.31-bfs221-smp Concurrency Level: 100 Time taken for tests: 43.556 seconds Complete requests: 500000 Failed requests: 0 Write errors: 0 Total transferred: 7158558404 bytes HTML transferred: 7027047358 bytes Requests per second: 11479.50 [#/sec] (mean) Time per request: 8.711 [ms] (mean) Time per request: 0.087 [ms] (mean, across all concurrent requests) Transfer rate: 160501.38 [Kbytes/sec] received 2.6.32-tip-smp NO_NEW_FAIR_SLEEPERS Concurrency Level: 100 Time taken for tests: 42.834 seconds Complete requests: 500000 Failed requests: 0 Write errors: 0 Total transferred: 7158429480 bytes HTML transferred: 7026921590 bytes Requests per second: 11672.84 [#/sec] (mean) Time per request: 8.567 [ms] (mean) Time per request: 0.086 [ms] (mean, across all concurrent requests) Transfer rate: 163201.63 [Kbytes/sec] received 2.6.32-tip-smp NEW_FAIR_SLEEPERS Concurrency Level: 100 Time taken for tests: 68.221 seconds Complete requests: 500000 Failed requests: 0 Write errors: 0 Total transferred: 7158357900 bytes HTML transferred: 7026851325 bytes Requests per second: 7329.12 [#/sec] (mean) Time per request: 13.644 [ms] (mean) Time per request: 0.136 [ms] (mean, across all concurrent requests) Transfer rate: 102469.65 [Kbytes/sec] received 2.6.32-tip-smp NEW_FAIR_SLEEPERS + ab at nice -15 Concurrency Level: 100 Time taken for tests: 42.824 seconds Complete requests: 500000 Failed requests: 0 Write errors: 0 Total transferred: 7158451988 bytes HTML transferred: 7026943572 bytes Requests per second: 11675.68 [#/sec] (mean) Time per request: 8.565 [ms] (mean) Time per request: 0.086 [ms] (mean, across all concurrent requests) Transfer rate: 163241.78 [Kbytes/sec] received taskset -c 2 /etc/init.d/apache2 restart taskset -c 3 ab -n 500000 -c 100 http://localhost/openSUSE.org.html 2.6.31-bfs221-smp Concurrency Level: 100 Time taken for tests: 86.590 seconds Complete requests: 500000 Failed requests: 0 Write errors: 0 Total transferred: 7158000000 bytes HTML transferred: 7026500000 bytes Requests per second: 5774.37 [#/sec] (mean) Time per request: 17.318 [ms] (mean) Time per request: 0.173 [ms] (mean, across all concurrent requests) Transfer rate: 80728.41 [Kbytes/sec] received 2.6.32-tip-smp Concurrency Level: 100 Time taken for tests: 48.640 seconds Complete requests: 500000 Failed requests: 0 Write errors: 0 Total transferred: 7158000000 bytes HTML transferred: 7026500000 bytes Requests per second: 10279.71 [#/sec] (mean) Time per request: 9.728 [ms] (mean) Time per request: 0.097 [ms] (mean, across all concurrent requests) Transfer rate: 143715.15 [Kbytes/sec] received -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/