From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261587AbVALX3T (ORCPT ); Wed, 12 Jan 2005 18:29:19 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261584AbVALX0s (ORCPT ); Wed, 12 Jan 2005 18:26:48 -0500 Received: from fw.osdl.org ([65.172.181.6]:35246 "EHLO mail.osdl.org") by vger.kernel.org with ESMTP id S261560AbVALX0J (ORCPT ); Wed, 12 Jan 2005 18:26:09 -0500 Date: Wed, 12 Jan 2005 15:30:33 -0800 From: Andrew Morton To: Nick Piggin Cc: clameter@sgi.com, torvalds@osdl.org, ak@muc.de, hugh@veritas.com, linux-mm@kvack.org, linux-ia64@vger.kernel.org, linux-kernel@vger.kernel.org, benh@kernel.crashing.org Subject: Re: page table lock patch V15 [0/7]: overview Message-Id: <20050112153033.6e2e4c6e.akpm@osdl.org> In-Reply-To: <41E5AFE6.6000509@yahoo.com.au> References: <41E4BCBE.2010001@yahoo.com.au> <20050112014235.7095dcf4.akpm@osdl.org> <20050112104326.69b99298.akpm@osdl.org> <41E5AFE6.6000509@yahoo.com.au> X-Mailer: Sylpheed version 0.9.7 (GTK+ 1.2.10; i586-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Nick Piggin wrote: > > So my patches cost about 7% in lmbench fork benchmark. OK, well that's the sort of thing we need to understand fully. What sort of CPU was that on? Look, -7% on a 2-way versus +700% on a many-way might well be a tradeoff we agree to take. But we need to fully understand all the costs and benefits.