From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 20 Sep 2001 17:11:08 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 20 Sep 2001 17:10:59 -0400 Received: from smtp10.atl.mindspring.net ([207.69.200.246]:7691 "EHLO smtp10.atl.mindspring.net") by vger.kernel.org with ESMTP id ; Thu, 20 Sep 2001 17:10:54 -0400 Subject: Re: [PATCH] Preemption Latency Measurement Tool From: Robert Love To: Andrea Arcangeli Cc: Dieter =?ISO-8859-1?Q?N=FCtzel?= , Roger Larsson , linux-kernel@vger.kernel.org, ReiserFS List In-Reply-To: <20010920102139.G729@athlon.random> In-Reply-To: <1000939458.3853.17.camel@phantasy> <20010920063143.424BD1E41A@Cantor.suse.de> <20010920084131.C1629@athlon.random> <20010920075751.6CA791E6B2@Cantor.suse.de> <20010920102139.G729@athlon.random> Content-Type: text/plain Content-Transfer-Encoding: 7bit X-Evolution-Format: text/plain X-Mailer: Evolution/0.13.99+cvs.2001.09.19.21.54 (Preview Release) Date: 20 Sep 2001 17:10:48 -0400 Message-Id: <1001020249.6048.152.camel@phantasy> Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2001-09-20 at 04:21, Andrea Arcangeli wrote: > > You've forgotten a one liner. > > > > #include > > +#include > > woops, didn't trapped it because of gcc 3.0.2. thanks. > > > But this is not enough. Even with reniced artsd (-20). > > Some shorter hiccups (0.5~1 sec). > > I'm not familiar with the output of the latency bench, but I actually > read "4617" usec as the worst latency, that means 4msec, not 500/1000 > msec. Right, the patch is returning the length preemption was unavailable (which is when a lock is held) in us. So it is indded 4ms. But, I think Dieter is saying he _sees_ 0.5~1s latencies (in the form of audio skips). This is despite the 4ms locks being held. -- Robert M. Love rml at ufl.edu rml at tech9.net