Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753148AbbHaOaZ (ORCPT ); Mon, 31 Aug 2015 10:30:25 -0400 Received: from relay.parallels.com ([195.214.232.42]:59934 "EHLO relay.parallels.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752054AbbHaOaX (ORCPT ); Mon, 31 Aug 2015 10:30:23 -0400 Date: Mon, 31 Aug 2015 17:30:08 +0300 From: Vladimir Davydov To: Tejun Heo CC: Michal Hocko , Andrew Morton , Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , , Subject: Re: [PATCH 0/2] Fix memcg/memory.high in case kmem accounting is enabled Message-ID: <20150831143007.GA13814@esperanza> References: <20150831132414.GG29723@dhcp22.suse.cz> <20150831134335.GB2271@mtj.duckdns.org> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20150831134335.GB2271@mtj.duckdns.org> X-ClientProxiedBy: US-EXCH2.sw.swsoft.com (10.255.249.46) To MSK-EXCH1.sw.swsoft.com (10.67.48.55) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1229 Lines: 25 On Mon, Aug 31, 2015 at 09:43:35AM -0400, Tejun Heo wrote: > On Mon, Aug 31, 2015 at 03:24:15PM +0200, Michal Hocko wrote: > > Right but isn't that what the caller explicitly asked for? Why should we > > ignore that for kmem accounting? It seems like a fix at a wrong layer to > > me. Either we should start failing GFP_NOWAIT charges when we are above > > high wmark or deploy an additional catchup mechanism as suggested by > > Tejun. I like the later more because it allows to better handle GFP_NOFS > > requests as well and there are many sources of these from kmem paths. > > Yeah, this is beginning to look like we're trying to solve the problem > at the wrong layer. slab/slub or whatever else should be able to use > GFP_NOWAIT in whatever frequency they want for speculative > allocations. slab/slub can issue alloc_pages() any time with any flags they want and it won't be accounted to memcg, because kmem is accounted at slab/slub layer, not in buddy. Thanks, Vladimir -- 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/