Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752842Ab0ADAts (ORCPT ); Sun, 3 Jan 2010 19:49:48 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752059Ab0ADAtr (ORCPT ); Sun, 3 Jan 2010 19:49:47 -0500 Received: from mail-pw0-f42.google.com ([209.85.160.42]:34420 "EHLO mail-pw0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751701Ab0ADAtr (ORCPT ); Sun, 3 Jan 2010 19:49:47 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; b=TLdDeIk+tgnamrGeaEPpJrNXvOILO8rNVa5XoK6vCxjqMHzqnKCqS3yMFnz6SuEEVF diI7N28iR4OsuYGbahxhMOGWuhv8cHPyy/bTXhkNVF+FlI7F0uxjt+k/ZYbg5KLNqyVR F96s4DIRvH7QdSpVKU4aWPeR8wmybxMq/aiZM= MIME-Version: 1.0 In-Reply-To: References: <4B38876F.6010204@gmail.com> <28c262360912301841r3ed43d31yc677fbc3a01fe5bb@mail.gmail.com> Date: Mon, 4 Jan 2010 09:49:46 +0900 Message-ID: <28c262361001031649w60a59151m8e210304217d4e35@mail.gmail.com> Subject: Re: [PATCH 2/3 -mmotm-2009-12-10-17-19] Count zero page as file_rss From: Minchan Kim To: Hugh Dickins Cc: Andrew Morton , LKML , linux-mm , KAMEZAWA Hiroyuki Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1876 Lines: 50 On Thu, Dec 31, 2009 at 5:43 PM, Hugh Dickins wrote: > On Thu, 31 Dec 2009, Minchan Kim wrote: >> On Thu, Dec 31, 2009 at 1:49 AM, Hugh Dickins >> wrote: >> > >> > You are right that I completely overlooked the issue of whether to >> > include the ZERO_PAGE in rss counts (now being a !vm_normal_page, >> > it was just natural to leave it out); and I overlooked the fact that >> > it used to be counted into file_rss in the old days (being !PageAnon). >> > >> > So I'm certainly at fault for that, and thank you for bringing the >> > issue to attention; but once considered, I can't actually see a good >> > reason why we should add code to count ZERO_PAGEs into file_rss now. >> > And if this patch falls, then 1/3 and 3/3 would fall also. >> > >> > And the patch below would be incomplete anyway, wouldn't it? >> > There would need to be a matching change to zap_pte_range(), >> > but I don't see that. >> >> Thanks. >> If we think this patch is need, I will repost path with fix it. >> >> What do you think? > > If someone comes up with a convincing case in which their system > is behaving significantly worse because the zero page is not being > counted in rss now, then we shall probably want your patch. > But I still don't yet see a reason to add code just to keep the > anon_rss+file_rss number looking the same as it was before, in this > exceptional case where there's a significant number of zero pages. Okay. I understand your point. I will repost this patch when we need this. :) Thanks for careful review, Hugh. > > Hugh > -- Kind regards, Minchan Kim -- 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/