Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261566AbTGAJON (ORCPT ); Tue, 1 Jul 2003 05:14:13 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261688AbTGAJON (ORCPT ); Tue, 1 Jul 2003 05:14:13 -0400 Received: from ppp-217-133-42-200.cust-adsl.tiscali.it ([217.133.42.200]:31927 "EHLO dualathlon.random") by vger.kernel.org with ESMTP id S261566AbTGAJOB (ORCPT ); Tue, 1 Jul 2003 05:14:01 -0400 Date: Tue, 1 Jul 2003 11:27:58 +0200 From: Andrea Arcangeli To: William Lee Irwin III , Joel.Becker@oracle.com, Mel Gorman , Linux Memory Management List , Linux Kernel Mailing List Subject: Re: What to expect with the 2.6 VM Message-ID: <20030701092758.GC3040@dualathlon.random> References: <20030701022516.GL3040@dualathlon.random> <20030701032531.GC20413@holomorphy.com> <20030701043902.GP3040@dualathlon.random> <20030701063317.GF20413@holomorphy.com> <20030701074915.GQ3040@dualathlon.random> <20030701085939.GG20413@holomorphy.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20030701085939.GG20413@holomorphy.com> User-Agent: Mutt/1.4i X-GPG-Key: 1024D/68B9CB43 13D9 8355 295F 4823 7C49 C012 DFA1 686E 68B9 CB43 X-PGP-Key: 1024R/CB4660B9 CC A0 71 81 F4 A0 63 AC C0 4B 81 1D 8C 15 C8 E5 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1692 Lines: 31 On Tue, Jul 01, 2003 at 01:59:39AM -0700, William Lee Irwin III wrote: > After observing that, the benchmark is flawed because > (a) it doesn't run long enough to produce stable numbers > (b) the results are apparently measured with gettimeofday(), which is > wildly inaccurate for such short-lived phenomena > (c) large differences in performance appear to come about as a result > of differing versions of common programs (i.e. gcc) not enough time right now to answer the whole email which is growing and growing in size ;), but I wanted to add a quick comment on this. many shell loads happens to do something similar, and the speed of compilation will be a very important factor until you rewrite make and gcc not to exit and to compile multiple files from a single invocation. The fact is that this is not a flawed benchmark, this is a real life workload that you can't avoid to deal with, and I want my kernel to run the fastest on the most common apps I run. I don't mind if swapping is slightly slower, I simply don't swap all the time for the whole system time, while I tend to keep the cpu 100% busy always. Still I want the best possible swapping that is zerocost for me on the other side. Giving me a CONFIG_SLOWSWAP_FAST_GCC would be more than enough to make me happy. I don't think I'll resist to the rmap slowdown while migrating to 2.6 if it keeps showing up in the profiling. Especially Martin's number were not good. Andrea - 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/