Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261471AbVAXGfr (ORCPT ); Mon, 24 Jan 2005 01:35:47 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261454AbVAXGdI (ORCPT ); Mon, 24 Jan 2005 01:33:08 -0500 Received: from mail.joq.us ([67.65.12.105]:37592 "EHLO sulphur.joq.us") by vger.kernel.org with ESMTP id S261471AbVAXG3G (ORCPT ); Mon, 24 Jan 2005 01:29:06 -0500 To: Ingo Molnar , Con Kolivas Cc: Paul Davis , linux , rlrevell@joe-job.com, CK Kernel , utz , Andrew Morton , alexn@dsv.su.se, Rui Nuno Capela Subject: Re: [PATCH]sched: Isochronous class v2 for unprivileged soft rt scheduling References: <200501201542.j0KFgOwo019109@localhost.localdomain> <87y8eo9hed.fsf@sulphur.joq.us> <20050120172506.GA20295@elte.hu> From: "Jack O'Quin" Date: Mon, 24 Jan 2005 00:30:48 -0600 In-Reply-To: <20050120172506.GA20295@elte.hu> (Ingo Molnar's message of "Thu, 20 Jan 2005 18:25:06 +0100") Message-ID: <877jm3qqxz.fsf@sulphur.joq.us> User-Agent: Gnus/5.1006 (Gnus v5.10.6) XEmacs/21.4 (Corporate Culture, linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1245 Lines: 26 Ingo Molnar writes: > just finished a short testrun with nice--20 compared to SCHED_FIFO, on a > relatively slow 466 MHz box: Has anyone done this kind of realtime testing on an SMP system? I'd love to know how they compare. Unfortunately, I don't have access to one at the moment. Are they generally better or worse for this kind of work? I'm not asking about partitioning or processor affinity, but actually using the entire SMP complex as a realtime machine. Our current jack_test scripts wouldn't exercise a multiprocessor very well. But, even those results would be interesting to know. Then, I think we could modify them to start muliple JACK servers. That will probably require using the dummy backend driver, which would need a more accurate timer source than its current usleep() call to provide reliable low latency results. (We currently drive the audio cycle from ALSA driver interrupts, but each JACK server requires a dedicated sound card for that.) -- joq - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/