From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S266339AbUGUO0I (ORCPT ); Wed, 21 Jul 2004 10:26:08 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S266391AbUGUO0I (ORCPT ); Wed, 21 Jul 2004 10:26:08 -0400 Received: from dns.gardena.net ([213.21.177.18]:1710 "HELO dns.gardena.net") by vger.kernel.org with SMTP id S266339AbUGUO0C (ORCPT ); Wed, 21 Jul 2004 10:26:02 -0400 Message-ID: <40FE7D4B.3080904@gardena.net> Date: Wed, 21 Jul 2004 16:27:23 +0200 From: Benno Senoner User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7b) Gecko/20040421 X-Accept-Language: en-us, en MIME-Version: 1.0 To: "The Linux Audio Developers' Mailing List" CC: Andrew Morton , linux-kernel Subject: Re: [linux-audio-dev] Re: [announce] [patch] Voluntary Kernel Preemption Patch References: <20040712163141.31ef1ad6.akpm@osdl.org> <1090306769.22521.32.camel@mindpipe> <20040720071136.GA28696@elte.hu> <200407202011.20558.musical_snake@gmx.de> <1090353405.28175.21.camel@mindpipe> <40FDAF86.10104@gardena.net> <1090369957.841.14.camel@mindpipe> In-Reply-To: <1090369957.841.14.camel@mindpipe> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Lee Revell wrote: >anyway. > > > > >>Plus what's very important is that every kernel developer and driver >>developer (even thirdparty, especially those >>that do closed source stuff like Nvidia etc) takes into account the >>latency problems that code paths that run for >>too long time (or disable IRQs for too long etc) might create. >>While I'm not a kernel expert I assume the premptible kernel alleviates >>this problem but I guess it still cannot >>completely get rid of low latency-unfriendly routines and drivers. >> >> > >Yes, this is important. One problem I had recently with the Via EPIA >board was that unless 2D acceleration was disabled by setting 'Option >"NoAccel"' in /etc/X11/XF86Config-4, overloading the X server would >cause interrupts from the soundcard to be completely disabled for tens >of milliseconds. Users should keep in mind that by using 2D or 3D >hardware acceleration in X, you are allowing the X server to directly >access hardware, which can have very bad results if the driver is >buggy. I am not sure the kernel can do anything about this. > > that's bad news. VIA markets those mini-itx mainboards (with onboard audio/video/network) as multimedia appliances and therefore I'd expect the hardware providing low latencies when both video acceleration and audio is used. Hopefully only a driver issue (as in most of cases) Since VIA released the unichrome (the gfx chipset contained in their mainboards) sources someone should contact these folks : http://unichrome.sourceforge.net/ to check what is causing those latency spikes ? Any unichrome developer lurking on LKML ? cheers, Benno http://www.linuxsampler.org >Lee > > > >