Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754676AbXE3NWd (ORCPT ); Wed, 30 May 2007 09:22:33 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751876AbXE3NW0 (ORCPT ); Wed, 30 May 2007 09:22:26 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:39821 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751188AbXE3NW0 (ORCPT ); Wed, 30 May 2007 09:22:26 -0400 Date: Wed, 30 May 2007 15:20:30 +0200 From: Ingo Molnar To: Jeff Garzik 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 Message-ID: <20070530132030.GA22330@elte.hu> References: <20070529212718.GH7875@mami.zabbo.net> <465CA654.5000505@garzik.org> <20070530072055.GA3077@elte.hu> <465D43A0.8040307@garzik.org> <20070530130237.GA19162@elte.hu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070530130237.GA19162@elte.hu> 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 Content-Length: 1465 Lines: 32 * Ingo Molnar wrote: > epoll is very much is capable of doing it - but why bother if > something more flexible than a ring can be used and the performance > difference is negligible? (Read my other reply in this thread for > further points.) in particular i'd like to (re-)stress this point: Thirdly, our main problem was not the structure of epoll, our main problem was that event APIs were not widely available, so applications couldnt go to a pure event based design - they always had to handle certain types of event domains specially, due to lack of coverage. The latest epoll patches largely address that. This was a huge barrier against adoption of epoll. starting with putting limits into the design by going to over-smart data structures like rings is just stupid. Lets fix, enhance and speed up what we have now (epoll) so that it becomes ubiquitous, and _then_ we can extend epoll to maybe fill events into rings. We should have our priorities right and should stop rewriting the whole world, especially when it comes to user APIs. Right now we have _no_ event API with complete coverage, and that's far more of a problem than the actual micro-structure of the API. 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/