From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755320AbYDTVlQ (ORCPT ); Sun, 20 Apr 2008 17:41:16 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751901AbYDTVlF (ORCPT ); Sun, 20 Apr 2008 17:41:05 -0400 Received: from one.firstfloor.org ([213.235.205.2]:37064 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751876AbYDTVlE (ORCPT ); Sun, 20 Apr 2008 17:41:04 -0400 Message-ID: <480BB85A.6020508@firstfloor.org> Date: Sun, 20 Apr 2008 23:40:42 +0200 From: Andi Kleen User-Agent: Thunderbird 1.5.0.12 (X11/20060911) MIME-Version: 1.0 To: Daniel Hazelton CC: Arjan van de Ven , Adrian Bunk , Alan Cox , Shawn Bohrer , Ingo Molnar , Andrew Morton , Linux Kernel Mailing List , Thomas Gleixner Subject: Re: x86: 4kstacks default References: <200804181737.m3IHbabI010051@hera.kernel.org> <20080420114845.77bf3fed@laptopd505.fenrus.org> <480BA12A.4000307@firstfloor.org> <200804201643.35830.dhazelton@enter.net> In-Reply-To: <200804201643.35830.dhazelton@enter.net> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Daniel Hazelton wrote: > At 12 threads per request it'd only take about 4200 outstanding requests. That > is high, but I can see it happening. If it happens it just won't work on 32bit. > Just makes you sound foolish. Run the numbers yourself and you'll see that it > is easy for a machine running highly threaded code to easily hit 50K threads. I ran the numbers and the numbers showed that you need > 1.5GB of lowmem with a somewhat realistic scenario (32K per thread) at 50k threads. And subtracting 4k from that 32k number won't make any significant difference (still 1.3GB) If you claim that works on a 32bit system with typically 300-600MB lowmem available (which is also shared by other subsystem) I know who sounds foolish. -Andi