From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1765565AbXGPXI1 (ORCPT ); Mon, 16 Jul 2007 19:08:27 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755536AbXGPXHr (ORCPT ); Mon, 16 Jul 2007 19:07:47 -0400 Received: from waste.org ([66.93.16.53]:48589 "EHLO waste.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1765399AbXGPXHq (ORCPT ); Mon, 16 Jul 2007 19:07:46 -0400 Date: Mon, 16 Jul 2007 18:07:19 -0500 From: Matt Mackall To: Rene Herman Cc: Ray Lee , Bodo Eggert <7eggert@gmx.de>, Jeremy Fitzhardinge , Jesper Juhl , Linux Kernel Mailing List , William Lee Irwin III , David Chinner , Arjan van de Ven Subject: Re: [PATCH][RFC] 4K stacks default, not a debug thing any more...? Message-ID: <20070716230719.GC11115@waste.org> References: <8Gj55-hJ-5@gated-at.bofh.it> <8GkNo-2Vb-1@gated-at.bofh.it> <8GtnN-7TG-23@gated-at.bofh.it> <8GVjY-PL-25@gated-at.bofh.it> <469A5D7C.5010904@gmail.com> <469BF104.1040703@gmail.com> <2c0942db0707161537o2852a308s26e79235e897e282@mail.gmail.com> <469BF768.6040200@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <469BF768.6040200@gmail.com> User-Agent: Mutt/1.5.13 (2006-08-11) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jul 17, 2007 at 12:55:36AM +0200, Rene Herman wrote: > On 07/17/2007 12:37 AM, Ray Lee wrote: > > >On 7/16/07, Rene Herman wrote: > > >>Seeing as how single-page stacks are much easier on the VM so that > >>creating those zillion threads should also be faster, at _some_ > >>percentage we get to say "and now to hell with the rest". > > > >This is the core dispute here. Stated differently, I hope you never > >design a bridge that I have to drive over. > > > >Correctness first, optimization second. Introducing random and > >difficult to trace crashes upon an unsuspecting audience of sysadmins > >and users is not a viable option. > > Quite. But unfortunately you didn't actually go into the bit on how given > seperate interrupt stacks, available stackspace might not actually _be_ > less after selecting CONFIG_4KSTCKS nor into Fedora and RHEL shipping it > already. > > >If at some point one of the pro-4k stacks crowd can prove that all > >code paths are safe > > I'll do that the minute you prove the current shared 8K stacks are safe. Do > we have a deal? > > >or introduce another viable alternative (such as Matt's idea for > >extending the stack dynamically), then removing the 8k stacks option > >makes sense. > > I'm still waiting for larger soft-pages... does anyone in this thread have > a clue on their status? Given that most x86 users won't want anything to do with them, it's not going to help us at all here. -- Mathematics is the supreme nostalgia of our time.