Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Sun, 13 Jan 2002 10:24:06 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sun, 13 Jan 2002 10:23:57 -0500 Received: from lilly.ping.de ([62.72.90.2]:30214 "HELO lilly.ping.de") by vger.kernel.org with SMTP id ; Sun, 13 Jan 2002 10:23:46 -0500 Date: 13 Jan 2002 16:22:58 +0100 Message-ID: <20020113162258.C1439@planetzork.spacenet> From: jogi@planetzork.ping.de To: "Ed Sweetman" Cc: "Andrea Arcangeli" , yodaiken@fsmlabs.com, "Robert Love" , "Alan Cox" , nigel@nrg.org, "Rob Landley" , "Andrew Morton" , linux-kernel@vger.kernel.org Subject: Re: [2.4.17/18pre] VM and swap - it's really unusable In-Reply-To: <1010781207.819.27.camel@phantasy> <20020112121315.B1482@inspiron.school.suse.de> <20020112160714.A10847@planetzork.spacenet> <20020112095209.A5735@hq.fsmlabs.com> <20020112180016.T1482@inspiron.school.suse.de> <005301c19b9b$6acc61e0$0501a8c0@psuedogod> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.3.15i In-Reply-To: <005301c19b9b$6acc61e0$0501a8c0@psuedogod>; from ed.sweetman@wmich.edu on Sat, Jan 12, 2002 at 02:00:17PM -0500 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Jan 12, 2002 at 02:00:17PM -0500, Ed Sweetman wrote: > > > > On Sat, Jan 12, 2002 at 09:52:09AM -0700, yodaiken@fsmlabs.com wrote: > > > On Sat, Jan 12, 2002 at 04:07:14PM +0100, jogi@planetzork.ping.de wrote: > > > > I did my usual compile testings (untar kernel archive, apply patches, > > > > make -j ... > > > > > > If I understand your test, > > > you are testing different loads - you are compiling kernels that may > differ > > > in size and makefile organization, not to mention different layout on > the > > > file system and disk. > > Can someone tell me why we're "testing" the preempt kernel by running > make -j on a build? What exactly is this going to show us? The only thing > i can think of is showing us that throughput is not damaged when you want to > run single apps by using preempt. You dont get to see the effects of the > kernel preemption because all the damn thing is doing is preempting itself. > > If you want to test the preempt kernel you're going to need something that > can find the mean latancy or "time to action" for a particular program or > all programs being run at the time and then run multiple programs that you > would find on various peoples' systems. That is the "feel" people talk > about when they praise the preempt patch. make -j'ing something and not > testing anything else but that will show you nothing important except "does > throughput get screwed by the preempt patch." Perhaps checking the > latencies on a common program on people's systems like mozilla or konqueror > while doing a 'make -j N bzImage' would be a better idea. That's the second test I am normally running. Just running xmms while doing the kernel compile. I just wanted to check if the system slows down because of preemption but instead it compiled the kernel even faster :-) But so far I was not able to test the latency and furthermore it is very difficult to "measure" skipping of xmms ... > > Ouch, I assumed this wasn't the case indeed. Sorry for not answering immedeatly but I am compiling the same kernel source with the same .config and everything I could think of being the same! I even do a 'rm -rf linux' after every run and untar the same sources *every* time. Regards, Jogi -- Well, yeah ... I suppose there's no point in getting greedy, is there? << Calvin & Hobbes >> - 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/