From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758760AbYDTOFx (ORCPT ); Sun, 20 Apr 2008 10:05:53 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752063AbYDTOFm (ORCPT ); Sun, 20 Apr 2008 10:05:42 -0400 Received: from sandeen.net ([209.173.210.139]:16016 "EHLO sandeen.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752187AbYDTOFl (ORCPT ); Sun, 20 Apr 2008 10:05:41 -0400 Message-ID: <480B4DB4.8070107@sandeen.net> Date: Sun, 20 Apr 2008 09:05:40 -0500 From: Eric Sandeen User-Agent: Thunderbird 2.0.0.12 (Macintosh/20080213) MIME-Version: 1.0 To: Adrian Bunk CC: Alan Cox , Shawn Bohrer , Ingo Molnar , Andrew Morton , Linux Kernel Mailing List , Arjan van de Ven , Thomas Gleixner Subject: Re: x86: 4kstacks default References: <20080419142329.GA5339@elte.hu> <20080419145948.GA4528@lintop> <20080420080901.GF1595@cs181133002.pp.htv.fi> <20080420090623.7b173ef1@the-village.bc.nu> <20080420085104.GG1595@cs181133002.pp.htv.fi> <20080420103611.2c0d3519@the-village.bc.nu> <20080420104444.GI1595@cs181133002.pp.htv.fi> <20080420120250.4f496861@the-village.bc.nu> <20080420115455.GJ1595@cs181133002.pp.htv.fi> <20080420123731.7282bb16@the-village.bc.nu> <20080420121803.GK1595@cs181133002.pp.htv.fi> In-Reply-To: <20080420121803.GK1595@cs181133002.pp.htv.fi> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Adrian Bunk wrote: > But the more users will get 4k stacks the more testing we have, and the > better both existing and new bugs get shaken out. > > And if there were only 4k stacks in the vanilla kernel, and therefore > all people on i386 testing -rc kernels would get it, that would give a > better chance of finding stack regressions before they get into a > stable kernel. Heck, maybe you should make it 2k by default in all -rc kernels; that way when people run -final with the 4k it'll be 100% bulletproof, right? 'cause all those piggy drivers that blow a 2k stack will finally have to get fixed? Or leave it at 2k and find a way to share pages for stacks, think how much memory you could save and how many java threads you could run! 4K just happens to be the page size; other than that it's really just some random/magic number picked, and now dictated that if you (and everyting around you) doesn't fit, you're broken. That bugs me. -Eric (yes, I know there are advantages to only allocating a single page for a new thread, but from an "all callchains after that must fit in that space" perspective, it's just a randomly picked number)