From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 22 Jan 2008 13:48:11 +0100 From: Ingo Molnar Subject: Re: [PATCH 0/3] x86: Reduce memory usage for large count NR_CPUs fixup V2 with git-x86 Message-ID: <20080122124811.GD7304@elte.hu> References: <20080121211618.599818000@sgi.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080121211618.599818000@sgi.com> Sender: owner-linux-mm@kvack.org Return-Path: To: travis@sgi.com Cc: Andrew Morton , Andi Kleen , Christoph Lameter , linux-mm@kvack.org, linux-kernel@vger.kernel.org List-ID: * travis@sgi.com wrote: > Fixup change NR_CPUS patchset by rebasing on 2.6.24-rc8-mm1 > from 2.6.24-rc6-mm1) and adding changes suggested by reviews. > > Based on 2.6.24-rc8-mm1 + latest (08/1/21) git-x86 > > Note there are two versions of this patchset: > - 2.6.24-rc8-mm1 > - 2.6.24-rc8-mm1 + latest (08/1/21) git-x86 thanks, applied. > Signed-off-by: Mike Travis > --- > Fixup-V2: > - pulled the SMP_MAX patch as it's not strictly needed and some > more work on local cpumask_t variables needs to be done before > NR_CPUS is allowed to increase. i'd still love to see CONFIG_SMP_MAX, so that we can have continuous randconfig testing of the large-SMP aspects of the x86 architecture, even on smaller systems. What's the maximum that should work right now? 256 or perhaps even 512 CPU ought to work fine i think? and then once the on-stack usage problems are fixed, the NR_CPUS value in CONFIG_SMP_MAX can be increased. So SMP_MAX would also act as "this is how far we can go in the upstream kernel" documentation. [ btw., the crash i remember was rather related to the NODES_SHIFT increase to 9, not from the NR_CPUSs increase. (the config i sent still has NR_CPUS==8, because Kconfig did not pick up the right NR_CPUs value dicatated by SMP_MAX.) If you resend the SMP_MAX patch against latest x86.git i can retest this. ] Ingo -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org