From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Sat, 22 Sep 2001 20:42:26 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sat, 22 Sep 2001 20:42:16 -0400 Received: from paloma12.e0k.nbg-hannover.de ([62.159.219.12]:24281 "HELO paloma12.e0k.nbg-hannover.de") by vger.kernel.org with SMTP id ; Sat, 22 Sep 2001 20:42:00 -0400 Content-Type: text/plain; charset="iso-8859-1" From: Dieter =?iso-8859-1?q?N=FCtzel?= Organization: DN To: safemode , Robert Love Subject: Re: [PATCH] Preemption Latency Measurement Tool Date: Sun, 23 Sep 2001 02:42:24 +0200 X-Mailer: KMail [version 1.3.1] Cc: linux-kernel In-Reply-To: <20010922211919Z272247-760+15646@vger.kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Message-Id: <20010923004207Z273037-760+15674@vger.kernel.org> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Am Sonntag, 23. September 2001 02:15 schrieb safemode: > On Saturday 22 September 2001 19:46, Dieter Nützel wrote: > > Am Sonntag, 23. September 2001 01:40 schrieb safemode: > > > ok. The preemption patch helps realtime applications in linux be a > > > little more close to realtime. I understand that. But your mp3 player > > > shouldn't need root permission or renicing or realtime priority flags > > > to play mp3s. To test how well the latency patches are working you > > > should be running things all at the same priority. The main issue > > > people are having with skipping mp3s is not in the decoding of the mp3 > > > or in the retrieving of the file, it's in the playing in the soundcard. > > > That's being affected by dbench flooding the system with irq requests. > > > I'm inclined to believe it's irq requests because the _only_ time i > > > have problems with mp3s (and i dont change priority levels) is when A. > > > i do a cdparanoia -Z -B "1-" or dbench 32. I bet if someone did > > > these tests on scsi hardware with the latency patch, they'd find much > > > better results than us users of ide devices. > > > > Nope. > > If you would have read (all) posts about this and related threads you > > should have noticed that I am and others running SCSI systems... > > hrmm strange because the only thing that could be causing the soundcard to > skip would be irq requests still stuck in the cpu as far as i know. I only > get that with massive ide access and that's it. Also that is when linux is > juggling them all equally. > > > > even i dont get any skips when i run the player at nice -n -20. > > > > During dbench 16/32 and higher? Are you sure? > > I ran it myself and i dont drink alcohol or take drugs. so yea, i'm sure > :) :-))) I would only to be sure. 'cause I get this regularly. > If i went high enough i suppose the same problem would occur. it's > probably in an area of the kernel where the preempt patch doesn't work > (yet). It does happen on cdparanoia -Z -B "1" I am under the impression that we didn't found the cause of it, yet. > I dont think anything ide is safe from that. No comment on this...:-) So, do you running ReiserFS or what? Thanks, Dieter