From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 26 Mar 2008 12:16:41 -0700 (PDT) From: Christoph Lameter Subject: Re: [PATCH 2/2] x86: Modify Kconfig to allow up to 4096 cpus In-Reply-To: <47EA7A5A.5030207@sgi.com> Message-ID: References: <20080326014137.934171000@polaris-admin.engr.sgi.com> <20080326014138.292294000@polaris-admin.engr.sgi.com> <20080326160924.GC1789@cs181133002.pp.htv.fi> <47EA7A5A.5030207@sgi.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: Mike Travis Cc: Adrian Bunk , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org List-ID: On Wed, 26 Mar 2008, Mike Travis wrote: > I guess the main effect is that "MAXSMP" represents what's really > usable for an architecture based on other factors. The limit of > NODES_SHIFT = 15 is that it's represented in some places as a signed > 16-bit value, so 15 is the hard limit without coding changes, not > an architecture limit. NODES_SHIFT also controls how many page flag bits are set aside for the node number. If you limit x86_64 to 512 nodes then lets keep this at 9. -- 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