From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S266364AbUHBJ2E (ORCPT ); Mon, 2 Aug 2004 05:28:04 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S266376AbUHBJ2E (ORCPT ); Mon, 2 Aug 2004 05:28:04 -0400 Received: from mx1.elte.hu ([157.181.1.137]:45995 "EHLO mx1.elte.hu") by vger.kernel.org with ESMTP id S266364AbUHBJ2B (ORCPT ); Mon, 2 Aug 2004 05:28:01 -0400 Date: Mon, 2 Aug 2004 11:28:55 +0200 From: Ingo Molnar To: Lee Revell Cc: linux-kernel Subject: Re: [patch] voluntary-preempt-2.6.8-rc2-M5 Message-ID: <20040802092855.GA15894@elte.hu> References: <20040729222657.GA10449@elte.hu> <1091141622.30033.3.camel@mindpipe> <20040730064431.GA17777@elte.hu> <1091228074.805.6.camel@mindpipe> <1091234100.1677.41.camel@mindpipe> <1091403477.862.4.camel@mindpipe> <1091407585.862.40.camel@mindpipe> <20040802073938.GA8332@elte.hu> <1091435237.3024.9.camel@mindpipe> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1091435237.3024.9.camel@mindpipe> User-Agent: Mutt/1.4.1i X-ELTE-SpamVersion: MailScanner 4.31.6-itk1 (ELTE 1.2) SpamAssassin 2.63 ClamAV 0.73 X-ELTE-VirusStatus: clean X-ELTE-SpamCheck: no X-ELTE-SpamCheck-Details: score=-4.9, required 5.9, autolearn=not spam, BAYES_00 -4.90 X-ELTE-SpamLevel: X-ELTE-SpamScore: -4 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org * Lee Revell wrote: > Can you post this patch, or add it to the voluntary preempt series? > The one posted several weeks ago worked for me but had to be applied > manually and has probably been improved since. > > Just to clarify the last numbers I posted were for O2. i've uploaded the preempt-timing patch (relative to -O2): http://redhat.com/~mingo/voluntary-preempt/preempt-timing-on-2.6.8-rc2-O2 QuickStart for those who havent used it yet: enable PREEMPT_TIMING in .config and add preempt_thresh=1000 [== 1000 usec threshold] to the kernel's boot options. i changed the original patch to make it a bit more usable - the threshold can be changed runtime via /proc/sys/kernel/preempt_thresh, and the units are microseconds not milliseconds. the timings should be pretty accurate in vp=0,1,2,3 modes as well. Note that this patch only measures latencies of critical sections (preempt-off sections), not other latencies that occur when running !CONFIG_PREEMPT or with kernel_preemption=0. Ingo