Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261683AbVCUIZq (ORCPT ); Mon, 21 Mar 2005 03:25:46 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261695AbVCUIYm (ORCPT ); Mon, 21 Mar 2005 03:24:42 -0500 Received: from ecfrec.frec.bull.fr ([129.183.4.8]:51840 "EHLO ecfrec.frec.bull.fr") by vger.kernel.org with ESMTP id S261696AbVCUIYL (ORCPT ); Mon, 21 Mar 2005 03:24:11 -0500 Subject: Re: [patch 1/2] fork_connector: add a fork connector From: Guillaume Thouvenin To: Jesse Barnes Cc: Evgeniy Polyakov , Andrew Morton , lkml , Jay Lan , Erich Focht , Ram , Gerrit Huizenga , elsa-devel , Greg KH In-Reply-To: <200503171405.55095.jbarnes@engr.sgi.com> References: <1111050243.306.107.camel@frecb000711.frec.bull.fr> <200503170856.57893.jbarnes@engr.sgi.com> <20050318003857.4600af78@zanzibar.2ka.mipt.ru> <200503171405.55095.jbarnes@engr.sgi.com> Date: Mon, 21 Mar 2005 09:23:51 +0100 Message-Id: <1111393431.8349.3.camel@frecb000711.frec.bull.fr> Mime-Version: 1.0 X-Mailer: Evolution 2.0.3 X-MIMETrack: Itemize by SMTP Server on ECN002/FR/BULL(Release 5.0.12 |February 13, 2003) at 21/03/2005 09:33:26, Serialize by Router on ECN002/FR/BULL(Release 5.0.12 |February 13, 2003) at 21/03/2005 09:33:35, Serialize complete at 21/03/2005 09:33:35 Content-Transfer-Encoding: 7bit Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1236 Lines: 33 On Thu, 2005-03-17 at 14:05 -0800, Jesse Barnes wrote: > On Thursday, March 17, 2005 1:38 pm, Evgeniy Polyakov wrote: > > The most significant part there - is requirement to store > > u32 seq in each CPU's cache and thus flush cacheline + > > invalidate/get from mem on each other cpus > > each time it is accessed, which is a big price. > > Same thing has to happen with the lock. To put it simply, writing global > variables from multiple CPUs with anything other than very low frequency is > bad. > > > It is totally Guillaume's work - so he decides, > > I would recomend per cpu counters and processor's > > id in each message. > > And of course userspace should take care of misordered > > messages. > > I personally prefer such mechanism. > > Yep, I agree. Hopefully Guillaume will too :) Sure, I agree and I will implement the per cpu counters solution with a processor id in each message. Thank you very much Jesse and Evgeniy for your great help, Best regards, Guillaume - 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/