From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261711AbULNWuk (ORCPT ); Tue, 14 Dec 2004 17:50:40 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261726AbULNWtj (ORCPT ); Tue, 14 Dec 2004 17:49:39 -0500 Received: from mustang.oldcity.dca.net ([216.158.38.3]:6589 "HELO mustang.oldcity.dca.net") by vger.kernel.org with SMTP id S261709AbULNWrP (ORCPT ); Tue, 14 Dec 2004 17:47:15 -0500 Subject: Re: [patch] Real-Time Preemption, -RT-2.6.10-rc3-mm1-V0.7.33-0 From: Lee Revell To: Ingo Molnar Cc: Steven Rostedt , LKML , Rui Nuno Capela , Mark Johnson , "K.R. Foley" , Bill Huey , Adam Heath , Florian Schmidt , Thomas Gleixner , Fernando Pablo Lopez-Lezcano , George Anzinger , Paul Davis In-Reply-To: <20041214223118.GD22043@elte.hu> References: <20041124101626.GA31788@elte.hu> <20041203205807.GA25578@elte.hu> <20041207132927.GA4846@elte.hu> <20041207141123.GA12025@elte.hu> <20041214132834.GA32390@elte.hu> <1103052853.3582.46.camel@localhost.localdomain> <1103054908.14699.20.camel@krustophenia.net> <1103057144.3582.51.camel@localhost.localdomain> <20041214211828.GA17216@elte.hu> <1103062423.14699.48.camel@krustophenia.net> <20041214223118.GD22043@elte.hu> Content-Type: text/plain Date: Tue, 14 Dec 2004 17:47:11 -0500 Message-Id: <1103064432.14699.69.camel@krustophenia.net> Mime-Version: 1.0 X-Mailer: Evolution 2.0.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2004-12-14 at 23:31 +0100, Ingo Molnar wrote: > * Lee Revell wrote: > > > On Tue, 2004-12-14 at 22:18 +0100, Ingo Molnar wrote: > > > the two projects are obviously complementary and i have no intention to > > > reinvent the wheel in any way. Best would be to bring hires timers up to > > > upstream-mergable state (independently of the -RT patch) and ask Andrew > > > to include it in -mm, then i'd port -RT to it automatically. > > > > Among other things I think Paul Davis mentioned that George's high res > > timer patch would make it possible for JACK to send MIDI clock. This > > would be a huge improvement. > > roughly what latency/accuracy requirements does the > MIDI clock have, and why is it an advantage if Linux generates it? What > generates it otherwise - external MIDI hardware? Or was the problem > mainly not latency/accuracy but that Linux couldnt generate a > finegrained enough clock? Being able to send or receive MIDI clock is a common feature for hardware and software samplers, sequencers, etc. It just allows more flexibility in your setup. I think currently Linux can receive MIDI clock better than it can send. To answer the last question I think the clock was not fine grained enough. But as far as timing requirements I don't actually know the details. Paul? Lee