From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752505AbXCDVtj (ORCPT ); Sun, 4 Mar 2007 16:49:39 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752506AbXCDVti (ORCPT ); Sun, 4 Mar 2007 16:49:38 -0500 Received: from mail06.syd.optusnet.com.au ([211.29.132.187]:55106 "EHLO mail06.syd.optusnet.com.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752505AbXCDVti (ORCPT ); Sun, 4 Mar 2007 16:49:38 -0500 From: Con Kolivas To: Al Boldi , ck list Subject: Re: [ANNOUNCE] RSDL completely fair starvation free interactive cpu scheduler Date: Mon, 5 Mar 2007 08:49:29 +1100 User-Agent: KMail/1.9.5 Cc: linux-kernel@vger.kernel.org References: <200703042335.26785.a1426z@gawab.com> In-Reply-To: <200703042335.26785.a1426z@gawab.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200703050849.29674.kernel@kolivas.org> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Monday 05 March 2007 07:35, Al Boldi wrote: > Con Kolivas wrote: > > > >> >> >This message is to announce the first general public release of > > > >> >> > the "Rotating Staircase DeadLine" cpu scheduler. > > Thanks a lot! You're welcome. > > > Just to make it clear. The purpose of this scheduler is at all costs to > > maintain absolute fairness no matter what type of load it is put under. > > Great! > > > This means that if you heavily load up your machine without the use of > > 'nice' then your interactive tasks _will_ slow down proportionately to > > the amount of cpu you use. So doing make -j4 for example will make any > > other task started in taht presence run precisely 1/5th speed, but they > > will still be responsive, have low latency (and audio shouldn't skip for > > example). > > That's just what it did, but when you "nice make -j4", things (gears) start > to stutter. Is that due to the staircase? gears isn't an interactive task. Apart from using it as a background load to check for starvation because it loads up the cpu fully (which a gpu intensive but otherwise simple app like this should _not_ do) graphics card drivers and interrupts and so on, I wouldn't put much credence on gears as anything else. However I suspect that gears will still get a fair share of the cpu on RSDL which almost never happens on any other scheduler. P.S. Al, please don't drop ccs from the original thread. -- -ck