Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751841AbXE3J20 (ORCPT ); Wed, 30 May 2007 05:28:26 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751029AbXE3J2S (ORCPT ); Wed, 30 May 2007 05:28:18 -0400 Received: from srv5.dvmed.net ([207.36.208.214]:60413 "EHLO mail.dvmed.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750888AbXE3J2R (ORCPT ); Wed, 30 May 2007 05:28:17 -0400 Message-ID: <465D43A0.8040307@garzik.org> Date: Wed, 30 May 2007 05:28:00 -0400 From: Jeff Garzik User-Agent: Thunderbird 1.5.0.10 (X11/20070302) MIME-Version: 1.0 To: Ingo Molnar CC: Zach Brown , linux-kernel@vger.kernel.org, Linus Torvalds , Arjan van de Ven , Christoph Hellwig , Andrew Morton , Alan Cox , Ulrich Drepper , Evgeniy Polyakov , "David S. Miller" , Suparna Bhattacharya , Davide Libenzi , Jens Axboe , Thomas Gleixner Subject: Re: Syslets, Threadlets, generic AIO support, v6 References: <20070529212718.GH7875@mami.zabbo.net> <465CA654.5000505@garzik.org> <20070530072055.GA3077@elte.hu> In-Reply-To: <20070530072055.GA3077@elte.hu> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Score: -4.3 (----) X-Spam-Report: SpamAssassin version 3.1.8 on srv5.dvmed.net summary: Content analysis details: (-4.3 points, 5.0 required) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1180 Lines: 31 Ingo Molnar wrote: > * Jeff Garzik wrote: > >> You should pick up the kevent work :) > > 3 months ago i verified the published kevent vs. epoll benchmark and > found that benchmark to be fatally flawed. When i redid it properly > kevent showed no significant advantage over epoll. Note that i did those > measurements _before_ the recent round of epoll speedups. So unless > someone does believable benchmarks i consider kevent an over-hyped, > mis-benchmarked complication to do something that epoll is perfectly > capable of doing. You snipped the key part of my response, so I'll say it again: Event rings (a) most closely match what is going on in the hardware and (b) often closely match what is going on in multi-socket, event-driven software application. To echo Uli and paraphrase an ad, "it's the interface, silly." This is not something epoll is capable of doing, at the present time. Jeff - 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/