From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail143.messagelabs.com (mail143.messagelabs.com [216.82.254.35]) by kanga.kvack.org (Postfix) with ESMTP id C802B90011A for ; Mon, 2 May 2011 03:22:56 -0400 (EDT) Date: Mon, 2 May 2011 09:22:10 +0200 From: Johannes Weiner Subject: Re: [PATCH 1/2] Add the soft_limit reclaim in global direct reclaim. Message-ID: <20110502072210.GA24305@cmpxchg.org> References: <1304030226-19332-1-git-send-email-yinghan@google.com> <1304030226-19332-2-git-send-email-yinghan@google.com> <20110429130503.GA306@tiehlicka.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: To: Ying Han Cc: Michal Hocko , KOSAKI Motohiro , Minchan Kim , Daisuke Nishimura , Balbir Singh , Tejun Heo , Pavel Emelyanov , KAMEZAWA Hiroyuki , Andrew Morton , Li Zefan , Mel Gorman , Christoph Lameter , Rik van Riel , Hugh Dickins , Dave Hansen , Zhu Yanhai , linux-mm@kvack.org On Fri, Apr 29, 2011 at 10:44:16AM -0700, Ying Han wrote: > On Fri, Apr 29, 2011 at 6:05 AM, Michal Hocko wrote: > > On Thu 28-04-11 15:37:05, Ying Han wrote: > >> We recently added the change in global background reclaim which > >> counts the return value of soft_limit reclaim. Now this patch adds > >> the similar logic on global direct reclaim. The changelog is a bit misleading: you don't just add something that counts something. You add code that can result in actual page reclamation. > >> @@ -1980,8 +1983,17 @@ static void shrink_zones(int priority, struct zonelist *zonelist, > >> continue; /* Let kswapd poll it */ > >> } > >> > >> + nr_soft_scanned = 0; > >> + nr_soft_reclaimed = mem_cgroup_soft_limit_reclaim(zone, > >> + sc->order, sc->gfp_mask, > >> + &nr_soft_scanned); > >> + sc->nr_reclaimed += nr_soft_reclaimed; > >> + total_scanned += nr_soft_scanned; > >> + > >> shrink_zone(priority, zone, sc); > > > > This can cause more aggressive reclaiming, right? Shouldn't we check > > whether shrink_zone is still needed? > > We decided to leave the shrink_zone for now before making further > changes for soft_limit reclaim. The same > patch I did last time for global background reclaim. It is safer to do > this step-by-step :) I am sorry, but I kinda lost track of what's going on because there are so many patches and concurrent discussions... who is we and do you have a pointer to the email where this conclusion was reached? And safe how? Do you want to trade a potential regression against a certain one (overreclaim)? -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org