From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261495AbVC0I6f (ORCPT ); Sun, 27 Mar 2005 03:58:35 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261485AbVC0I6f (ORCPT ); Sun, 27 Mar 2005 03:58:35 -0500 Received: from mx1.elte.hu ([157.181.1.137]:20679 "EHLO mx1.elte.hu") by vger.kernel.org with ESMTP id S261480AbVC0I60 (ORCPT ); Sun, 27 Mar 2005 03:58:26 -0500 Date: Sun, 27 Mar 2005 10:58:14 +0200 From: Ingo Molnar To: Lee Revell Cc: linux-kernel@vger.kernel.org, "Paul E. McKenney" Subject: Re: [patch] Real-Time Preemption, -RT-2.6.12-rc1-V0.7.41-10 Message-ID: <20050327085814.GA23082@elte.hu> References: <20050325145908.GA7146@elte.hu> <1111790009.23430.19.camel@mindpipe> <20050325223959.GA24800@elte.hu> <1111814065.24049.21.camel@mindpipe> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1111814065.24049.21.camel@mindpipe> User-Agent: Mutt/1.4.2.1i 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: > Running for several days with PREEMPT_DESKTOP, on the Athlon XP the > worst latency I am seeing is ~150 usecs! But on the C3 its about 4ms: could you run a bit with tracing disabled (in the .config) on the C3? (but wakeup timing still enabled) It may very well be tracing overhead that makes those latencies that high. Also, we'd thus have some hard data on how much overhead tracing is in such a situation, on that CPU. Ingo