Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263593AbTH0QCi (ORCPT ); Wed, 27 Aug 2003 12:02:38 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263553AbTH0QAg (ORCPT ); Wed, 27 Aug 2003 12:00:36 -0400 Received: from holomorphy.com ([66.224.33.161]:33208 "EHLO holomorphy") by vger.kernel.org with ESMTP id S263530AbTH0QA2 (ORCPT ); Wed, 27 Aug 2003 12:00:28 -0400 Date: Wed, 27 Aug 2003 09:01:33 -0700 From: William Lee Irwin III To: Larry McVoy , Peter Chubb , akpm@digeo.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH] 2.6.0-test4 -- add context switch counters Message-ID: <20030827160133.GD4306@holomorphy.com> Mail-Followup-To: William Lee Irwin III , Larry McVoy , Peter Chubb , akpm@digeo.com, linux-kernel@vger.kernel.org References: <16204.520.61149.961640@wombat.disy.cse.unsw.edu.au> <20030827065435.GV4306@holomorphy.com> <20030827155246.GA23609@work.bitmover.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20030827155246.GA23609@work.bitmover.com> Organization: The Domain of Holomorphy User-Agent: Mutt/1.5.4i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1136 Lines: 23 On Wed, Aug 27, 2003 at 08:52:46AM -0700, Larry McVoy wrote: > I normally hate ifdefs but this might be a good place to use a bunch of > macros and make them conditional on config_stats or something. Updating > counters is going to add to the size of the data cache footprint and it > would be nice, for those people working on embedded low speed processors, > if they could config this out. I personally would leave it in, I like > this stats. I just know that the path to slowness is paved one cache > miss at a time. I've profiled this and know the memory stats don't do any harm; the rest I'd have to see profiled. AFAICT all the damage is done after ticking mm->rss in the various pagetable copying/blitting operations, and once we've taken that hit (in mainline!) the other counters are noise-level. The integral counters are another story; I've not seen those in action. -- wli - 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/