Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Tue, 18 Dec 2001 14:06:56 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 18 Dec 2001 14:05:18 -0500 Received: from lacrosse.corp.redhat.com ([12.107.208.154]:61173 "EHLO lacrosse.corp.redhat.com") by vger.kernel.org with ESMTP id ; Tue, 18 Dec 2001 14:03:28 -0500 Message-ID: <3C1F92FF.3030701@redhat.com> Date: Tue, 18 Dec 2001 14:03:27 -0500 From: Doug Ledford User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:0.9.6+) Gecko/20011211 X-Accept-Language: en-us MIME-Version: 1.0 To: Andreas Dilger CC: Kernel Mailing List Subject: Re: Scheduler ( was: Just a second ) ... In-Reply-To:

<20011218105459.X855@lynx.no> <3C1F8A9E.3050409@redhat.com> <20011218115243.Y855@lynx.no> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Andreas Dilger wrote: > Hmm, I _do_ notice a pop when the sound hardware is first initialized at > boot time, but not when mpg123 starts/stops (without esd running) so I > personally don't get any benefit from "the sound of silence". That said, > asside from the 190 interrupts/sec from esd, it doesn't appear to use any > measurable CPU time by itself. > > >>Context switches per second not playing any sound: 8300 - 8800 >>Context switches per second playing an MP3: 9200 - 9900 >> > > Hmm, something seems very strange there. On an idle system, I get about > 100 context switches/sec, and about 150/sec when playing sound (up to 400/sec > when moving the mouse between windows). 9000 cswitches/sec is _very_ high. > This is with a text-only player which has screen output (other than the > ID3 info from the currently played song). I haven't taken the time to track down what's causing all the context switches, but on my system they are indeed "normal". I suspect large numbers of them are a result of interactions between gnome, nautilus, X, xmms, esd, and gnome-xmms. However, I did just track down one reason for it. It's not 8300 - 8800, its 830 - 880. There appears to be a bug in the procinfo -n1 mode that results in an extra digit getting tacked onto the end of the context switch line. So, take my original numbers and lop off the last digit from the context switch numbers and that's more like what the machine is actually doing. -- Doug Ledford http://people.redhat.com/dledford Please check my web site for aic7xxx updates/answers before e-mailing me about problems - 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/