From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with SMTP id B952D60021B for ; Tue, 29 Dec 2009 22:11:30 -0500 (EST) Subject: Re: [PATCH -mmotm-2009-12-10-17-19] Fix wrong rss count of smaps From: Matt Mackall In-Reply-To: <20091230103349.1ec71aac.minchan.kim@barrios-desktop> References: <20091228134619.92ba28f6.minchan.kim@barrios-desktop> <1262117339.3000.2023.camel@calx> <20091230103349.1ec71aac.minchan.kim@barrios-desktop> Content-Type: text/plain; charset="UTF-8" Date: Tue, 29 Dec 2009 21:11:26 -0600 Message-ID: <1262142686.3000.2140.camel@calx> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Minchan Kim Cc: Andrew Morton , lkml , linux-mm , KAMEZAWA Hiroyuki , Hugh Dickins List-ID: On Wed, 2009-12-30 at 10:33 +0900, Minchan Kim wrote: > Hi, Matt. > > On Tue, 29 Dec 2009 14:08:59 -0600 > Matt Mackall wrote: > > > On Mon, 2009-12-28 at 13:46 +0900, Minchan Kim wrote: > > > I am not sure we have to account zero page with file_rss. > > > Hugh and Kame's new zero page doesn't do it. > > > As side effect of this, we can prevent innocent process which have a lot > > > of zero page when OOM happens. > > > (But I am not sure there is a process like this :) > > > So I think not file_rss counting is not bad. > > > > > > RSS counting zero page with file_rss helps any program using smaps? > > > If we have to keep the old behavior, I have to remake this patch. > > > > > > == CUT_HERE == > > > > > > Long time ago, We regards zero page as file_rss and > > > vm_normal_page doesn't return NULL. > > > > > > But now, we reinstated ZERO_PAGE and vm_normal_page's implementation > > > can return NULL in case of zero page. Also we don't count it with > > > file_rss any more. > > > > > > Then, RSS and PSS can't be matched. > > > For consistency, Let's ignore zero page in smaps_pte_range. > > > > > > > Not counting the zero page in RSS is fine with me. But will this patch > > make the total from smaps agree with get_mm_rss()? > > Yes. Anon page fault handler also don't count zero page any more, now. > Nonetheless, smaps counts it with resident. Ok, great. Acked-by: Matt Mackall -- http://selenic.com : development and support for Mercurial and Linux -- 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