From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752880AbXDOPj6 (ORCPT ); Sun, 15 Apr 2007 11:39:58 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752869AbXDOPj6 (ORCPT ); Sun, 15 Apr 2007 11:39:58 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:43756 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752817AbXDOPj5 (ORCPT ); Sun, 15 Apr 2007 11:39:57 -0400 Date: Sun, 15 Apr 2007 17:39:33 +0200 From: Ingo Molnar To: Willy Tarreau Cc: Pekka Enberg , hui Bill Huey , Con Kolivas , ck list , Peter Williams , linux-kernel@vger.kernel.org, Linus Torvalds , Andrew Morton , Nick Piggin , Mike Galbraith , Arjan van de Ven , Thomas Gleixner Subject: Re: [Announce] [patch] Modular Scheduler Core and Completely Fair Scheduler [CFS] Message-ID: <20070415153933.GB6623@elte.hu> References: <20070413202100.GA9957@elte.hu> <200704151327.13589.kernel@kolivas.org> <20070415051645.GA28438@gnuppy.monkey.org> <20070415084447.GC24886@elte.hu> <20070415095146.GA30327@gnuppy.monkey.org> <84144f020704150339i4a0d437fja6868ab671558ba1@mail.gmail.com> <20070415124527.GP943@1wt.eu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070415124527.GP943@1wt.eu> User-Agent: Mutt/1.4.2.2i X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -2.0 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-2.0 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.1.7 -2.0 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org * Willy Tarreau wrote: > Ingo could have publicly spoken with them about his ideas of killing > the O(1) scheduler and replacing it with an rbtree-based one, [...] yes, that's precisely what i did, via a patchset :) [ I can even tell you when it all started: i was thinking about Mike's throttling patches while watching Manchester United beat the crap out of AS Roma (7 to 1 end result), Thuesday evening. I started coding it Wednesday morning and sent the patch Friday evening. I very much believe in low-latency when it comes to development too ;) ] (if this had been done via a comittee then today we'd probably still be trying to find a suitable timeslot for the initial conference call where we'd discuss the election of a chair who would be tasked with writing up an initial document of feature requests, on which we'd take a vote, possibly this year already, because the matter is really urgent you know ;-) > [...] and using part of Bill's work to speed up development. ok, let me make this absolutely clear: i didnt use any bit of plugsched - in fact the most difficult bits of the modularization was for areas of sched.c that plugsched never even touched AFAIK. (the load-balancer for example.) Plugsched simply does something else: i modularized scheduling policies in essence that have to cooperate with each other, while plugsched modularized complete schedulers which are compile-time or boot-time selected, with no runtime cooperation between them. (one has to be selected at a time) (and i have no trouble at all with crediting Will's work either: a few years ago i used Will's PID rework concepts for an NPTL related speedup and Will is very much credited for it in today's kernel/pid.c and he continued to contribute to it later on.) (the tree walking bits of sched_fair.c were in fact derived from kernel/hrtimer.c, the rbtree code written by Thomas and me :-) Ingo