From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andi Kleen Subject: Re: [PATCH 00/10] x86: Reduce memory and intra-node effects with large count NR_CPUs Date: Mon, 14 Jan 2008 11:04:18 +0100 References: <20080113183453.973425000@sgi.com> <20080114081418.GB18296@elte.hu> In-Reply-To: <20080114081418.GB18296@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200801141104.18789.ak@suse.de> Sender: owner-linux-mm@kvack.org Return-Path: To: Ingo Molnar Cc: travis@sgi.com, Andrew Morton , Christoph Lameter , Jack Steiner , linux-mm@kvack.org, linux-kernel@vger.kernel.org List-ID: > i.e. we've got ~22K bloat per CPU - which is not bad, but because it's a > static component, it hurts smaller boxes. For distributors to enable > CONFIG_NR_CPU=1024 by default i guess that bloat has to drop below 1-2K > per CPU :-/ [that would still mean 1-2MB total bloat but that's much > more acceptable than 23MB] Even 1-2MB overhead would be too much for distributors I think. Ideally there must be near zero overhead for possible CPUs (and I see no principle reason why this is not possible) Worst case a low few hundred KBs, but even that would be much. There are the cpusets which get passed around, but these are only one bit per possible CPU. -Andi -- 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