From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1422737AbXBARNv (ORCPT ); Thu, 1 Feb 2007 12:13:51 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1422747AbXBARNv (ORCPT ); Thu, 1 Feb 2007 12:13:51 -0500 Received: from rtr.ca ([64.26.128.89]:1654 "EHLO mail.rtr.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1422737AbXBARNu (ORCPT ); Thu, 1 Feb 2007 12:13:50 -0500 Message-ID: <45C21FCC.7040406@rtr.ca> Date: Thu, 01 Feb 2007 12:13:48 -0500 From: Mark Lord User-Agent: Thunderbird 1.5.0.9 (X11/20061206) MIME-Version: 1.0 To: Ingo Molnar Cc: Christoph Hellwig , Zach Brown , linux-kernel@vger.kernel.org, linux-aio@kvack.org, Suparna Bhattacharya , Benjamin LaHaise , Linus Torvalds Subject: Re: [PATCH 2 of 4] Introduce i386 fibril scheduling References: <20070201083611.GC18233@elte.hu> <20070201130234.GA15257@elte.hu> <20070201131903.GA24683@infradead.org> <20070201135215.GA23477@elte.hu> In-Reply-To: <20070201135215.GA23477@elte.hu> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Ingo Molnar wrote: > > also, we context-switch kernel threads in 350 nsecs on current hardware > and the -rt kernel is certainly happy with that and runs all hardirqs Ingo, how relevant is that "350 nsecs on current hardware" claim? I don't mean that in a bad way, but my own experience suggests that most people doing real hard RT (or tight soft RT) are not doing it on x86 architectures. But rather on lowly 1GHz (or less) ARM based processors and the like. For RT issues, those are the platforms I care more about, as those are the ones that get embedded into real-time devices. ?? Cheers