Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753398AbbHCNYl (ORCPT ); Mon, 3 Aug 2015 09:24:41 -0400 Received: from gum.cmpxchg.org ([85.214.110.215]:48710 "EHLO gum.cmpxchg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752121AbbHCNYk (ORCPT ); Mon, 3 Aug 2015 09:24:40 -0400 Date: Mon, 3 Aug 2015 09:23:58 -0400 From: Johannes Weiner To: Vladimir Davydov Cc: Andrew Morton , Michal Hocko , Minchan Kim , Rik van Riel , Mel Gorman , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/3] mm: make workingset detection logic memcg aware Message-ID: <20150803132358.GA18399@cmpxchg.org> References: <9662034e14549b9e1445684f674063ce8b092cb0.1438599199.git.vdavydov@parallels.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <9662034e14549b9e1445684f674063ce8b092cb0.1438599199.git.vdavydov@parallels.com> User-Agent: Mutt/1.5.23+102 (2ca89bed6448) (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1127 Lines: 26 On Mon, Aug 03, 2015 at 03:04:22PM +0300, Vladimir Davydov wrote: > @@ -179,8 +180,9 @@ static void unpack_shadow(void *shadow, > eviction = entry; > > *zone = NODE_DATA(nid)->node_zones + zid; > + *lruvec = mem_cgroup_page_lruvec(page, *zone); > > - refault = atomic_long_read(&(*zone)->inactive_age); > + refault = atomic_long_read(&(*lruvec)->inactive_age); > mask = ~0UL >> (NODES_SHIFT + ZONES_SHIFT + > RADIX_TREE_EXCEPTIONAL_SHIFT); > /* You can not compare an eviction shadow entry from one lruvec with the inactive age of another lruvec. The inactive ages are not related and might differ significantly: memcgs are created ad hoc, memory hotplug, page allocator fairness drift. In those cases the result will be pure noise. As much as I would like to see a simpler way, I am pessimistic that there is a way around storing memcg ids in the shadow entries. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/