Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S270715AbTG0KTJ (ORCPT ); Sun, 27 Jul 2003 06:19:09 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S270711AbTG0KTJ (ORCPT ); Sun, 27 Jul 2003 06:19:09 -0400 Received: from mx2.elte.hu ([157.181.151.9]:23996 "EHLO mx2.elte.hu") by vger.kernel.org with ESMTP id S270715AbTG0KTG (ORCPT ); Sun, 27 Jul 2003 06:19:06 -0400 Date: Sun, 27 Jul 2003 12:26:56 +0200 (CEST) From: Ingo Molnar Reply-To: Ingo Molnar To: Guillaume Chazarain Cc: Davide Libenzi , Mike Galbraith , Subject: Re: [patch] sched-2.6.0-test1-G3, interactivity changes, audio latency In-Reply-To: Message-ID: 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: 1045 Lines: 26 On Sat, 26 Jul 2003, Guillaume Chazarain wrote: > BTW, with your nanosecond resolution, mplayer is also max interactive. good. > Don't you find it strange to need a nanosecond resolution to evaluate a > simple integer in a [-5, 5] range? no, i dont find it strange, as the -5..5 integer range is only the end result. What we really want is an accurate sleep average, the integral of sleep times done over the last N seconds. Given that tasks can schedule at very high frequencies these days, this needs accurate measurements. I used to hope that a 1 msec sampling frequency would to be enough for this, but when we fix the statistics cornercase you mention, another cornercase pops up. And it's not _that_ hard to use the cycle counter and still have a reasonably fast algorithm, anyway. Ingo - 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/