Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753198AbYL3Tfz (ORCPT ); Tue, 30 Dec 2008 14:35:55 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751971AbYL3Tfr (ORCPT ); Tue, 30 Dec 2008 14:35:47 -0500 Received: from mx01.mailboxcop.com ([206.125.223.71]:47644 "EHLO mx01.mailboxcop.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751989AbYL3Tfq (ORCPT ); Tue, 30 Dec 2008 14:35:46 -0500 Message-ID: <495A788B.3010001@jaysonking.com> Date: Tue, 30 Dec 2008 13:37:47 -0600 From: Jayson King User-Agent: Thunderbird 2.0.0.18 (X11/20081119) MIME-Version: 1.0 To: linux-kernel@vger.kernel.org CC: a.p.zijlstra@chello.nl, mingo@elte.hu Subject: Re: problem with "sched: revert back to per-rq vruntime"? References: <495948E0.8040502@jaysonking.com> In-Reply-To: <495948E0.8040502@jaysonking.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Canit-CHI2: 0.50 X-Bayes-Prob: 0.9891 (Score 4, tokens from: @@RPTN, outgoing) X-Spam-Score: 4.10 (****) [Hold at 5.20] RDNS_NONE,2(1.2),6947(-1.2),Bayes(0.9891,4.0) X-CanItPRO-Stream: outgoing (inherits from default) X-Canit-Stats-ID: 333068985 - dd8405089393 X-Antispam-Training-Forget: http://mailboxcop.com/canit/b.php?i=333068985&m=dd8405089393&c=f X-Antispam-Training-Nonspam: http://mailboxcop.com/canit/b.php?i=333068985&m=dd8405089393&c=n X-Antispam-Training-Spam: http://mailboxcop.com/canit/b.php?i=333068985&m=dd8405089393&c=s Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2132 Lines: 109 Here's some times using bash, for example. Let me know if there are some other tests I can do. It shows on vanilla 2.6.28, a huge increase in latency (about 37X to 39X) starting bash -i when the CPU is loaded with 100% nice tasks, relative to idle CPU. But after reverting f9c0b0950d5fd8c8c5af39bc061f27ea8fddcac3 the latency increase is not as great (about 2X). # running bash -i on vanilla 2.6.28, # with idle CPU [jayson@atlas tmp]$ time bash -i -c 'exit' exit real 0m0.020s user 0m0.008s sys 0m0.014s [jayson@atlas tmp]$ time bash -i -c 'exit' exit real 0m0.020s user 0m0.014s sys 0m0.005s [jayson@atlas tmp]$ time bash -i -c 'exit' exit real 0m0.020s user 0m0.008s sys 0m0.009s # running bash -i on vanilla 2.6.28, # with 100% nice CPU usage [jayson@atlas tmp]$ time bash -i -c 'exit' exit real 0m0.753s user 0m0.011s sys 0m0.011s [jayson@atlas tmp]$ time bash -i -c 'exit' exit real 0m0.752s user 0m0.012s sys 0m0.012s [jayson@atlas tmp]$ time bash -i -c 'exit' exit real 0m0.786s user 0m0.010s sys 0m0.008s # running 2.6.28 reverted f9c0b0950d5fd8c8c5af39bc061f27ea8fddcac3, # with idle CPU [jayson@atlas tmp]$ time bash -i -c 'exit' exit real 0m0.021s user 0m0.012s sys 0m0.007s [jayson@atlas tmp]$ time bash -i -c 'exit' exit real 0m0.020s user 0m0.012s sys 0m0.011s [jayson@atlas tmp]$ time bash -i -c 'exit' exit real 0m0.020s user 0m0.011s sys 0m0.012s # running 2.6.28 reverted f9c0b0950d5fd8c8c5af39bc061f27ea8fddcac3, # with 100% nice CPU usage [jayson@atlas tmp]$ time bash -i -c 'exit' exit real 0m0.043s user 0m0.010s sys 0m0.009s [jayson@atlas tmp]$ time bash -i -c 'exit' exit real 0m0.046s user 0m0.011s sys 0m0.007s [jayson@atlas tmp]$ time bash -i -c 'exit' exit real 0m0.047s user 0m0.011s sys 0m0.006s Jayson -- 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/