Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S265132AbUFGX61 (ORCPT ); Mon, 7 Jun 2004 19:58:27 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S265135AbUFGX61 (ORCPT ); Mon, 7 Jun 2004 19:58:27 -0400 Received: from bhhdoa.org.au ([216.17.101.199]:54023 "EHLO bhhdoa.org.au") by vger.kernel.org with ESMTP id S265132AbUFGX6Y (ORCPT ); Mon, 7 Jun 2004 19:58:24 -0400 Message-ID: <1086644098.40c4df826be23@vds.kolivas.org> Date: Tue, 8 Jun 2004 07:34:58 +1000 From: Con Kolivas To: Phy Prabab Cc: Linux Kernel Mailinglist , Zwane Mwaikambo , William Lee Irwin III Subject: Re: [PATCH] Staircase Scheduler v6.3 for 2.6.7-rc2 References: <20040607214034.27475.qmail@web51807.mail.yahoo.com> In-Reply-To: <20040607214034.27475.qmail@web51807.mail.yahoo.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT User-Agent: Internet Messaging Program (IMP) 3.2.2 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2532 Lines: 71 Quoting Phy Prabab : > OOOPPPSSSS.... > > I need to make a correction on my previous data. I > had inadvertantly turned off interactivity and also > increased the compute time to 100. I confirmed that > just setting interactivity off, does not solve my > problem: > > 2.6.7-rc3-s63 (0 @ /proc/sys/kernel/interactive): > A: 37.30user 40.56system 1:42.01elapsed 76%CPU > B: 37.29user 40.35system 1:23.87elapsed 92%CPU > C: 37.30user 40.56system 1:36.01elapsed 81%CPU > > 2.6.7-rc3-s63 (0 @ /proc/sys/kernel/interactive & 1 > /proc/sys/kernel/compute): > A: 37.28user 40.36system 1:25.60elapsed 90%CPU > B: 37.22user 40.35system 1:22.17elapsed 94%CPU > C: 37.27user 40.35system 1:24.71elapsed 91%CPU > > The question here, noticing that user and kernel time > are the same, where is the dead time coming from and > why is it sooooo much more deterministic with compute > time at 100 vs 10? Maybe I am misinterpreting the > data, but this suggests to me that something is going > awry (ping-pong, no settle, ???) within the kernl? > > > Also please note the degredation between > 2.6.7-rc2-bk8-s63: > > A: 35.57user 38.18system 1:20.28elapsed 91%CPU > B: 35.54user 38.40system 1:19.48elapsed 93%CPU > C: 35.48user 38.28system 1:20.94elapsed 91%CPU > > Interesting how much more time is spent in both user > and kernel space between the two kernels. Also note > that 2.4.x exhibits even greater delta: > > A: 28.32user 29.51system 1:01.17elapsed 93%CPU > B: 28.54user 29.40system 1:01.48elapsed 92%CPU > B: 28.23user 28.80system 1:00.21elapsed 94%CPU > > Could anyone suggest a way to understand why the > difference between the 2.6 kernels and the 2.4 > kernels? > > Thank you for your time. > Phy > Hi. How repeatable are the numbers normally? Some idea of what it is you're benchmarking may also help in understanding the problem; locking may be an issue with what you're benchmarking and out-of-order scheduling is not as forgiving of poor locking. Extending the RR_INTERVAL and turning off interactivity makes it more in-order and more forgiving of poor locking or yield(). Compute==1 setting inactivates interactivity anyway, but that's not really relevant to your figures since you had set interactive 0 when you set compute 1. Con - 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/