From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755424Ab2LLV4E (ORCPT ); Wed, 12 Dec 2012 16:56:04 -0500 Received: from mx1.redhat.com ([209.132.183.28]:52169 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755168Ab2LLV4C (ORCPT ); Wed, 12 Dec 2012 16:56:02 -0500 Message-ID: <50C8FCE0.1060408@redhat.com> Date: Wed, 12 Dec 2012 16:53:36 -0500 From: Rik van Riel User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:15.0) Gecko/20120911 Thunderbird/15.0.1 MIME-Version: 1.0 To: Johannes Weiner CC: Andrew Morton , Michal Hocko , Mel Gorman , Hugh Dickins , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [patch 1/8] mm: memcg: only evict file pages when we have plenty References: <1355348620-9382-1-git-send-email-hannes@cmpxchg.org> <1355348620-9382-2-git-send-email-hannes@cmpxchg.org> In-Reply-To: <1355348620-9382-2-git-send-email-hannes@cmpxchg.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/12/2012 04:43 PM, Johannes Weiner wrote: > dc0422c "mm: vmscan: only evict file pages when we have plenty" makes > a point of not going for anonymous memory while there is still enough > inactive cache around. > > The check was added only for global reclaim, but it is just as useful > for memory cgroup reclaim. > > Signed-off-by: Johannes Weiner > --- > mm/vmscan.c | 19 ++++++++++--------- > 1 file changed, 10 insertions(+), 9 deletions(-) > > diff --git a/mm/vmscan.c b/mm/vmscan.c > index 157bb11..3874dcb 100644 > --- a/mm/vmscan.c > +++ b/mm/vmscan.c > @@ -1671,6 +1671,16 @@ static void get_scan_count(struct lruvec *lruvec, struct scan_control *sc, > denominator = 1; > goto out; > } > + /* > + * There is enough inactive page cache, do not reclaim > + * anything from the anonymous working set right now. > + */ > + if (!inactive_file_is_low(lruvec)) { > + fraction[0] = 0; > + fraction[1] = 1; > + denominator = 1; > + goto out; > + } > > anon = get_lru_size(lruvec, LRU_ACTIVE_ANON) + > get_lru_size(lruvec, LRU_INACTIVE_ANON); > @@ -1688,15 +1698,6 @@ static void get_scan_count(struct lruvec *lruvec, struct scan_control *sc, > fraction[1] = 0; > denominator = 1; > goto out; > - } else if (!inactive_file_is_low_global(zone)) { > - /* > - * There is enough inactive page cache, do not > - * reclaim anything from the working set right now. > - */ > - fraction[0] = 0; > - fraction[1] = 1; > - denominator = 1; > - goto out; > } > } > > I believe the if() block should be moved to AFTER the check where we make sure we actually have enough file pages.