From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S268277AbUHXUcu (ORCPT ); Tue, 24 Aug 2004 16:32:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S268276AbUHXUcu (ORCPT ); Tue, 24 Aug 2004 16:32:50 -0400 Received: from viper.oldcity.dca.net ([216.158.38.4]:43681 "HELO viper.oldcity.dca.net") by vger.kernel.org with SMTP id S268280AbUHXUcg (ORCPT ); Tue, 24 Aug 2004 16:32:36 -0400 Subject: Re: [patch] voluntary-preempt-2.6.8.1-P9 From: Lee Revell To: "K.R. Foley" Cc: Ingo Molnar , Scott Wood , manas.saksena@timesys.com, linux-kernel In-Reply-To: <412B7E50.1030806@cybsft.com> References: <20040823221816.GA31671@yoda.timesys> <20040824061459.GA29630@elte.hu> <412B7E50.1030806@cybsft.com> Content-Type: text/plain Message-Id: <1093379558.817.60.camel@krustophenia.net> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.4.6 Date: Tue, 24 Aug 2004 16:32:39 -0400 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2004-08-24 at 13:43, K.R. Foley wrote: > Ingo Molnar wrote: > > * Scott Wood wrote: > > > > > >>I have attached a port of the voluntary preempt patch to PPC and > >>PPC64. The patch is against P7, but it applies against P8 as well. > > > > > > thanks Scott, i've applied your patch to my tree - all the changes and > > improvements look good (except for a small compilation problem on x86, > > asm/time.h doesnt exist there - asm/rtc.h does). The resulting code > > booted fine on an SMP and on a UP x86 system. I've uploaded -P9: > > > > http://redhat.com/~mingo/voluntary-preempt/voluntary-preempt-2.6.8.1-P9 > > > > (there are no other changes in -P9.) > > > > Ingo > > - > > ~254 usec latency seen in kswapd: > > http://www.cybsft.com/testresults/2.6.8.1-P9/latency_trace2.txt > I am able to generate unbounded latencies in kswapd by running `make -j12' for any C++ program that uses KDE/Qt. The build will allocate all available RAM, then all available swap, then the machine grinds to a halt. I am not sure this is solvable though. If you fire off a bunch of processes that try to allocate way more memory than is physically available then you will have worse problems than latency. Lee