From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Mon, 15 Jan 2001 05:54:14 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Mon, 15 Jan 2001 05:53:55 -0500 Received: from horus.its.uow.edu.au ([130.130.68.25]:17033 "EHLO horus.its.uow.edu.au") by vger.kernel.org with ESMTP id ; Mon, 15 Jan 2001 05:53:34 -0500 Message-ID: <3A62D82F.49BF3693@uow.edu.au> Date: Mon, 15 Jan 2001 21:59:59 +1100 From: Andrew Morton X-Mailer: Mozilla 4.7 [en] (X11; I; Linux 2.4.0 i586) X-Accept-Language: en MIME-Version: 1.0 To: Gregory Maxwell CC: lkml , lad Subject: Re: low-latency scheduling patch for 2.4.0 In-Reply-To: <3A57DA3E.6AB70887@uow.edu.au> <3A618F17.FD285E2B@uow.edu.au>, <3A618F17.FD285E2B@uow.edu.au>; from andrewm@uow.edu.au on Sun, Jan 14, 2001 at 10:35:51PM +1100 <20010114093836.C10910@xi.linuxpower.cx> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Gregory Maxwell wrote: > > On Sun, Jan 14, 2001 at 10:35:51PM +1100, Andrew Morton wrote: > [snip] > > - The patch now works properly on SMP. > [snip] > > Any benchmark results on SMP yet? SMP and UP are much the same. Workload is `make -j3 bzImage', the measured time is from entry to an ISR to execution of the userspace process. The histogram has 10 microsecond resolution. SMP === 0:165601 10:17192 20:12769 30:33220 40:59318 50:60814 60:42915 70:20949 80:8124 90:2590 100:944 110:397 120:211 130:96 140:51 150:41 160:36 170:24 180:21 190:15 200:14 210:12 220:13 230:7 240:11 250:6 260:3 270:4 280:10 290:6 300:5 310:3 320:3 330:6 340:1 350:1 370:1 400:1 620:1 Total samples: 425436 So on SMP, latency is < 10 microseconds 165601/425436 = 39% of the time. UP == 0:52735 10:33480 20:101199 30:200301 40:135470 50:9199 60:4356 70:1531 80:770 90:396 100:288 110:178 120:102 130:100 140:63 150:45 160:61 170:40 180:30 190:23 200:29 210:12 220:26 230:10 240:8 250:6 260:2 300:1 Total samples: 540461 In other words: SMP === usecs 0 -100: 99.54% 100-200: 0.43% 200-300: 0.02% 300-400: 0.0049% 620: 0.00023% UP == 0 -100: 99.81% 100-200: 0.17% 200-300: 0.017% - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/