Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965061AbVLHANN (ORCPT ); Wed, 7 Dec 2005 19:13:13 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S965064AbVLHANN (ORCPT ); Wed, 7 Dec 2005 19:13:13 -0500 Received: from smtp018.mail.yahoo.com ([216.136.174.115]:54388 "HELO smtp018.mail.yahoo.com") by vger.kernel.org with SMTP id S965061AbVLHANM (ORCPT ); Wed, 7 Dec 2005 19:13:12 -0500 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com.au; h=Received:Message-ID:Date:From:User-Agent:X-Accept-Language:MIME-Version:To:CC:Subject:References:In-Reply-To:Content-Type:Content-Transfer-Encoding; b=N8URW1dhBXEsS5n9pdGusib/ak5HJ6tR2jag6LQjlJBjR6pDlxBnXaMhdNxWQv49L7xRlgkDyGfLmskwVOuH/69sX+h1Zx1TCz2M5aPOed4vaLFC8vY/uVdMA8tAQ5QWuN7Aavlp4ejDDK/BAU5bGG+mZgSLhFzqWr0cRIa2dR4= ; Message-ID: <43977A92.3090206@yahoo.com.au> Date: Thu, 08 Dec 2005 11:13:06 +1100 From: Nick Piggin User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.12) Gecko/20051007 Debian/1.7.12-1 X-Accept-Language: en MIME-Version: 1.0 To: Christoph Lameter CC: linux-kernel@vger.kernel.org, Hugh Dickins , linux-mm@kvack.org, Andi Kleen , Marcelo Tosatti Subject: Re: [RFC 1/3] Framework for accurate node based statistics References: <20051206182843.19188.82045.sendpatchset@schroedinger.engr.sgi.com> <439619F9.4030905@yahoo.com.au> <439684C0.9090107@yahoo.com.au> <43976949.8010205@yahoo.com.au> In-Reply-To: Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1492 Lines: 48 Christoph Lameter wrote: > On Thu, 8 Dec 2005, Nick Piggin wrote: > > >>Christoph Lameter wrote: >> >>>On Wed, 7 Dec 2005, Nick Piggin wrote: >>> >>>>Sorry, I think I meant: why don't you just use the "add all counters >>>>from all per-cpu of the node" in order to find the node-statistic? >>> >>>which function is that? >>> >> >>I'm thinking of get_page_state_node... but that's not quite the same >>thing. I guess sum all per-CPU counters from all zones in the node, >>but that's going to be costly on big machines. > > > The per cpu counters count when a cpu did an allocation. They do not count > on which node the allocation was done and are thereofre not useful to > determine the memory use on one node. > Yes, not that exact function of course. > >>So I'm not sure, I guess I don't have any bright ideas... there is the >>batching approach used by current pagecache_acct - is something like >>that not sufficient either? > > > The framework provides a similar approach by keeping differential > counters for each processor. > But the accounting delay has the unbounded error problem that the batching approach does not. -- SUSE Labs, Novell Inc. Send instant messages to your online friends http://au.messenger.yahoo.com - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/