Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752822AbXE3IzD (ORCPT ); Wed, 30 May 2007 04:55:03 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751707AbXE3Iyt (ORCPT ); Wed, 30 May 2007 04:54:49 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:57327 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752479AbXE3Iyr (ORCPT ); Wed, 30 May 2007 04:54:47 -0400 Date: Wed, 30 May 2007 10:54:00 +0200 From: Ingo Molnar To: Evgeniy Polyakov Cc: Jeff Garzik , Zach Brown , linux-kernel@vger.kernel.org, Linus Torvalds , Arjan van de Ven , Christoph Hellwig , Andrew Morton , Alan Cox , Ulrich Drepper , "David S. Miller" , Suparna Bhattacharya , Davide Libenzi , Jens Axboe , Thomas Gleixner Subject: Re: Syslets, Threadlets, generic AIO support, v6 Message-ID: <20070530085400.GA17744@elte.hu> References: <20070529212718.GH7875@mami.zabbo.net> <465CA654.5000505@garzik.org> <20070530072055.GA3077@elte.hu> <20070530083254.GA21528@2ka.mipt.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070530083254.GA21528@2ka.mipt.ru> 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=3.0.3 -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 Content-Length: 1660 Lines: 38 * Evgeniy Polyakov wrote: > I did not want to start with another round of ping-pong insults :), > but, Ingo, you did not show that kevent works worse. I did show that > sometimes it works better. It flawed from 0 to 30% win in that tests, > in results Johann Bork presented kevent and epoll behaved the same. In > results I posted earlier, I said, that sometimes epoll behaved better, > sometimes kevent. [...] let me refresh your recollection: http://lkml.org/lkml/2007/2/25/116 where you said: "But note, that on my athlon64 3500 test machine kevent is about 7900 requests per second compared to 4000+ epoll, so expect a challenge." for a long time you made much fuss about how kevents is so much better and how epoll cannot perform and scale as well (you said various arguments why that is supposedly so), and some people bought into the performance argument and advocated kevent due to its supposed performance and scalability advantages - while now we are down to "epoll and kevent are break-even"? in my book that is way too much of a difference, it is (best-case) a way too sloppy approach to something as fundamental as Linux's basic event model and design, and it is also compounded by your continued "nothing happened, really, lets move on" stance. Losing trust is easy, winning it back is hard. Let me reuse a phrase of yours: "expect a challenge". Ingo - 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/