From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264726AbUHJMjh (ORCPT ); Tue, 10 Aug 2004 08:39:37 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264767AbUHJMjh (ORCPT ); Tue, 10 Aug 2004 08:39:37 -0400 Received: from mx2.elte.hu ([157.181.151.9]:23690 "EHLO mx2.elte.hu") by vger.kernel.org with ESMTP id S264726AbUHJMjS (ORCPT ); Tue, 10 Aug 2004 08:39:18 -0400 Date: Tue, 10 Aug 2004 14:40:20 +0200 From: Ingo Molnar To: Alan Cox Cc: Lee Revell , Florian Schmidt , Linux Kernel Mailing List , Felipe Alfaro Solana Subject: Re: [patch] voluntary-preempt-2.6.8-rc3-O4 Message-ID: <20040810124020.GA18904@elte.hu> References: <20040726204720.GA26561@elte.hu> <20040729222657.GA10449@elte.hu> <20040801193043.GA20277@elte.hu> <20040809104649.GA13299@elte.hu> <20040809130558.GA17725@elte.hu> <20040809190201.64dab6ea@mango.fruits.de> <1092103522.761.2.camel@mindpipe> <20040810085849.GC26081@elte.hu> <20040810092249.GA29875@elte.hu> <1092137588.16885.4.camel@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1092137588.16885.4.camel@localhost.localdomain> 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 * Alan Cox wrote: > > another (more remote) possibility is that the timestamp counter gets > > somehow messed up during MMX ops. Does the ALSA detector use the > > timestamp counter, or does it only use jiffies? (if it only used jiffies > > that would give us some robustness since it's an independent > > time-source.) I suspect 'music indeed skips' isnt a good enough test for > > this case, given that jackd starts up ... > > The standard VIA EPIA boards are 133Mhz SDRAM or 266Mhz DDR, which is > shared with video and the graphics engine. Could the MMX copier simply > be eating all the remaining memory bandwidth so that its in fact > memory not latency ? it's a 10 msec latency that got measured, for a single page copy (!) - if it's memory latency then it must be something really bad... Ingo