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 17:35:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 20 Sep 2001 17:35:19 -0400 Received: from paloma13.e0k.nbg-hannover.de ([62.159.219.13]:20157 "HELO paloma13.e0k.nbg-hannover.de") by vger.kernel.org with SMTP id ; Thu, 20 Sep 2001 17:35:00 -0400 Content-Type: text/plain; charset=US-ASCII From: Dieter =?iso-8859-1?q?N=FCtzel?= Organization: DN To: Robert Love , Andrea Arcangeli Subject: Re: [PATCH] Preemption Latency Measurement Tool Date: Thu, 20 Sep 2001 23:35:18 +0200 X-Mailer: KMail [version 1.3.1] Cc: Roger Larsson , linux-kernel@vger.kernel.org, ReiserFS List In-Reply-To: <1000939458.3853.17.camel@phantasy> <20010920102139.G729@athlon.random> <1001020249.6048.152.camel@phantasy> In-Reply-To: <1001020249.6048.152.camel@phantasy> MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Message-Id: <20010920213510Z274657-760+14618@vger.kernel.org> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Am Donnerstag, 20. September 2001 23:10 schrieb Robert Love: > 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. Yes, that's the case. During dbench 16,32,40,48, etc... -Dieter