From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759605AbbLCK7x (ORCPT ); Thu, 3 Dec 2015 05:59:53 -0500 Received: from mail-wm0-f50.google.com ([74.125.82.50]:38003 "EHLO mail-wm0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756616AbbLCK7w (ORCPT ); Thu, 3 Dec 2015 05:59:52 -0500 Date: Thu, 3 Dec 2015 11:59:48 +0100 From: Michal Hocko To: "Pradeep Goswami (Pradeep Kumar Goswami)" Cc: "rebecca@android.com" , "vdavydov@parallels.com" , "akpm@linux-foundation.org" , "vbabka@suse.cz" , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , "sanjeev.yadav@spreatrum.com" Subject: Re: [PATCH]mm:Correctly update number of rotated pages on active list. Message-ID: <20151203105948.GE9264@dhcp22.suse.cz> References: <20151203100809.GA4544@pradeepkumarubtnb.spreadtrum.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20151203100809.GA4544@pradeepkumarubtnb.spreadtrum.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu 03-12-15 10:08:11, Pradeep Goswami (Pradeep Kumar Goswami) wrote: > This patch corrects the number of pages which are rotated on active list. > The counter for rotated pages effects the number of pages > to be scanned on active pages list in low memory situations. Why this should be changed? This seems to be deliberate: /* * Count referenced pages from currently used mappings as rotated, * even though only some of them are actually re-activated. This * helps balance scan pressure between file and anonymous pages in * get_scan_count. */ reclaim_stat->recent_rotated[file] += nr_rotated; What kind of problem are you trying to fix? > > Signed-off-by: Pradeep Goswami > Cc: Rebecca Schultz Zavin > Cc: Vladimir Davydov > Cc: Andrew Morton > --- > --- a/mm/vmscan.c 2015-11-18 20:55:38.208838142 +0800 > +++ b/mm/vmscan.c 2015-11-19 14:37:31.189838998 +0800 > @@ -1806,7 +1806,6 @@ static void shrink_active_list(unsigned > > if (page_referenced(page, 0, sc->target_mem_cgroup, > &vm_flags)) { > - nr_rotated += hpage_nr_pages(page); > /* > * Identify referenced, file-backed active pages and > * give them one more trip around the active list. So > @@ -1818,6 +1817,7 @@ static void shrink_active_list(unsigned > */ > if ((vm_flags & VM_EXEC) && page_is_file_cache(page)) { > list_add(&page->lru, &l_active); > + nr_rotated += hpage_nr_pages(page); > continue; > } > } > > Thanks, > Pradeep. > -- > 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 -- Michal Hocko SUSE Labs