From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx130.postini.com [74.125.245.130]) by kanga.kvack.org (Postfix) with SMTP id 4A2EC6B005D for ; Thu, 13 Dec 2012 00:56:35 -0500 (EST) Received: by mail-ie0-f169.google.com with SMTP id c14so3492391ieb.14 for ; Wed, 12 Dec 2012 21:56:34 -0800 (PST) Message-ID: <1355378190.1567.6.camel@kernel.cn.ibm.com> Subject: Re: [patch 2/8] mm: vmscan: disregard swappiness shortly before going OOM From: Simon Jeons Date: Wed, 12 Dec 2012 23:56:30 -0600 In-Reply-To: <1355348620-9382-3-git-send-email-hannes@cmpxchg.org> References: <1355348620-9382-1-git-send-email-hannes@cmpxchg.org> <1355348620-9382-3-git-send-email-hannes@cmpxchg.org> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Johannes Weiner Cc: Andrew Morton , Rik van Riel , Michal Hocko , Mel Gorman , Hugh Dickins , linux-mm@kvack.org, linux-kernel@vger.kernel.org On Wed, 2012-12-12 at 16:43 -0500, Johannes Weiner wrote: > When a reclaim scanner is doing its final scan before giving up and > there is swap space available, pay no attention to swappiness > preference anymore. Just swap. > Confuse! If it's final scan and still swap space available, why nr[lru] = div64_u64(scan * fraction[file], denominator); instead of nr[lru] = scan; ? > Note that this change won't make too big of a difference for general > reclaim: anonymous pages are already force-scanned when there is only > very little file cache left, and there very likely isn't when the > reclaimer enters this final cycle. > > Signed-off-by: Johannes Weiner > --- > mm/vmscan.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/vmscan.c b/mm/vmscan.c > index 3874dcb..6e53446 100644 > --- a/mm/vmscan.c > +++ b/mm/vmscan.c > @@ -1751,7 +1751,7 @@ static void get_scan_count(struct lruvec *lruvec, struct scan_control *sc, > unsigned long scan; > > scan = get_lru_size(lruvec, lru); > - if (sc->priority || noswap || !vmscan_swappiness(sc)) { > + if (sc->priority || noswap) { > scan >>= sc->priority; > if (!scan && force_scan) > scan = SWAP_CLUSTER_MAX; -- 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