From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932782AbXCBINj (ORCPT ); Fri, 2 Mar 2007 03:13:39 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932785AbXCBINj (ORCPT ); Fri, 2 Mar 2007 03:13:39 -0500 Received: from relay.2ka.mipt.ru ([194.85.82.65]:36178 "EHLO 2ka.mipt.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932782AbXCBINi (ORCPT ); Fri, 2 Mar 2007 03:13:38 -0500 Date: Fri, 2 Mar 2007 11:10:48 +0300 From: Evgeniy Polyakov To: Davide Libenzi Cc: Ingo Molnar , Eric Dumazet , Pavel Machek , Theodore Tso , Linus Torvalds , Ulrich Drepper , Linux Kernel Mailing List , Arjan van de Ven , Christoph Hellwig , Andrew Morton , Alan Cox , Zach Brown , "David S. Miller" , Suparna Bhattacharya , Jens Axboe , Thomas Gleixner Subject: Re: [patch 00/13] Syslets, "Threadlets", generic AIO support, v3 Message-ID: <20070302081047.GA27122@2ka.mipt.ru> References: <20070301095402.GA14603@elte.hu> <20070301131118.GA30228@elte.hu> <20070301133018.GB30177@2ka.mipt.ru> <200703011519.20001.dada1@cosmosbay.com> <20070301141637.GA20006@elte.hu> <20070301145454.GB12684@2ka.mipt.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=koi8-r Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.9i X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-3.0 (2ka.mipt.ru [0.0.0.0]); Fri, 02 Mar 2007 11:11:26 +0300 (MSK) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Mar 01, 2007 at 11:31:14AM -0800, Davide Libenzi (davidel@xmailserver.org) wrote: > On Thu, 1 Mar 2007, Evgeniy Polyakov wrote: > > > Ingo, do you really think I will send mails with faked benchmarks? :)) > > I don't think he ever implied that. He was only suggesting that when you > post benchmarks, and even more when you make claims based on benchmarks, > you need to be extra carefull about what you measure. Otherwise the > external view that you give to others does not look good. > Kevent can be really faster than epoll, but if you post broken benchmarks > (that can be, unrealiable HTTP loaders, broken server implemenations, > etc..) and make claims based on that, the only effect that you have is to > lose your point. We seems to move far away from original topic - I never built any assumptions on top of kevent _performance_ - kevent is a logical extrapolation of the epoll, I only showed that event driven model can be fast and it outperforms threadlet one - after we changed topic we were unable to actually test threadlets in networking environment, since the only test I ran showed that threadlest do not reschedule at all, and Ingo's tests showed small number of reschedulings. So, I only talked that kevent is superior compared to epoll because (and it is _main_ issue) of its ability to handle essentially any kind of events with very small overhead (the same as epoll has in struct file - list and spinlock) and without significant price of struct file binding to event. I did not want and do not want to hurt anyone (even Ingo, although he is against kevent :), but my opinion is that thread moved from nice discussion about threads and events with jokes and fun into quite angry word throwings, and that is too good - let's make it fun again. I'm not a native english speaker (and do not use a dictionary), so it is quite possible that some my phrases were not exactly nice, but it was unintentional (at least not very) :) Peace? > - Davide > -- Evgeniy Polyakov