From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755821Ab1ATPAP (ORCPT ); Thu, 20 Jan 2011 10:00:15 -0500 Received: from smtp110.prem.mail.ac4.yahoo.com ([76.13.13.93]:45642 "HELO smtp110.prem.mail.ac4.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1755736Ab1ATPAN (ORCPT ); Thu, 20 Jan 2011 10:00:13 -0500 X-Yahoo-SMTP: _Dag8S.swBC1p4FJKLCXbs8NQzyse1SYSgnAbY0- X-YMail-OSG: _k5HKLUVM1mP.bxTMyHNBkcK6e4m_r8.Kz_2uEBrO604bUA uFkFyWtZO6lC2e7N3iXOsX7YKgehpvDdJvPnrxXgjS1ul1RYjCEF.8r05sHt BY7vspf5axUQzDmIWsYFsVidY9XVvqePDWCH30OFbAYMvPn.cyFTpqaTnObX DHstFZ6.Pq567iIKj3KxV942E.gR7yKVGgiJ9p7UvaI5Sd4W2ju6g0nbAdWs .C7aIoPwjLyE- X-Yahoo-Newman-Property: ymail-3 Date: Thu, 20 Jan 2011 09:00:09 -0600 (CST) From: Christoph Lameter X-X-Sender: cl@router.home To: Balbir Singh cc: linux-mm@kvack.org, akpm@linux-foundation.org, npiggin@kernel.dk, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, kosaki.motohiro@jp.fujitsu.com, kamezawa.hiroyu@jp.fujitsu.com Subject: Re: [REPOST] [PATCH 3/3] Provide control over unmapped pages (v3) In-Reply-To: <20110120123649.30481.93286.stgit@localhost6.localdomain6> Message-ID: References: <20110120123039.30481.81151.stgit@localhost6.localdomain6> <20110120123649.30481.93286.stgit@localhost6.localdomain6> User-Agent: Alpine 2.00 (DEB 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 20 Jan 2011, Balbir Singh wrote: > + unmapped_page_control > + [KNL] Available if CONFIG_UNMAPPED_PAGECACHE_CONTROL > + is enabled. It controls the amount of unmapped memory > + that is present in the system. This boot option plus > + vm.min_unmapped_ratio (sysctl) provide granular control min_unmapped_ratio is there to guarantee that zone reclaim does not reclaim all unmapped pages. What you want here is a max_unmapped_ratio. > { > @@ -2297,6 +2320,12 @@ loop_again: > shrink_active_list(SWAP_CLUSTER_MAX, zone, > &sc, priority, 0); > > + /* > + * We do unmapped page reclaim once here and once > + * below, so that we don't lose out > + */ > + reclaim_unmapped_pages(priority, zone, &sc); > + > if (!zone_watermark_ok_safe(zone, order, Hmmmm. Okay that means background reclaim does it. If so then we also want zone reclaim to be able to work in the background I think. max_unmapped_ratio could also be useful to the zone reclaim logic.