From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S267374AbUHJBAH (ORCPT ); Mon, 9 Aug 2004 21:00:07 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S267375AbUHJBAG (ORCPT ); Mon, 9 Aug 2004 21:00:06 -0400 Received: from mustang.oldcity.dca.net ([216.158.38.3]:33729 "HELO mustang.oldcity.dca.net") by vger.kernel.org with SMTP id S267373AbUHJA7x (ORCPT ); Mon, 9 Aug 2004 20:59:53 -0400 Subject: Re: 2.4.x vs 2.6.x: denormal handling and audio performance From: Lee Revell To: Fernando Pablo Lopez-Lezcano Cc: linux-kernel , jackit-devel In-Reply-To: <1092079195.16794.257.camel@cmn37.stanford.edu> References: <1092079195.16794.257.camel@cmn37.stanford.edu> Content-Type: text/plain Message-Id: <1092099606.22613.12.camel@mindpipe> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.4.6 Date: Mon, 09 Aug 2004 21:00:07 -0400 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2004-08-09 at 15:19, Fernando Pablo Lopez-Lezcano wrote: > Hi all, I've been trying to track weird behavior I'm experiencing when > trying to use 2.6.x for "pro audio" applications and I think I have > something to report (and some questions). > > First, the environment. I'm running the Jack low latency server on top > of two different software installs on the same hardware, one is FC1 + > 2.4.26 + low latency and preemption patches, the other is FC2 + 2.6.7 > rc2-mm2 + voluntary preemption O3. They are different hard disks swapped > into the same P4 laptop. Both are running the same source code versions > of all the audio programs that I use to test (but _not_ the same > binaries, each one is built in the environment it runs on). > Have you tried using the exact same binaries under both 2.4 and 2.6? This would rule out a compiler issue. In case anyone thinks this is an application bug, here are some links pertaining to the P4 denormals-are-zero issue, these were at the bottom of Fernando's post: http://gcc.gnu.org/ml/gcc/2001-07/msg02162.html http://lkml.org/lkml/2003/5/9/144 Lee