From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx142.postini.com [74.125.245.142]) by kanga.kvack.org (Postfix) with SMTP id 2C5C36B005D for ; Wed, 9 Jan 2013 15:37:39 -0500 (EST) Received: by mail-da0-f51.google.com with SMTP id i30so924289dad.10 for ; Wed, 09 Jan 2013 12:37:38 -0800 (PST) Date: Wed, 9 Jan 2013 12:37:31 -0800 From: Tejun Heo Subject: Re: [PATCH 1/2] Add mempressure cgroup Message-ID: <20130109203731.GA20454@htj.dyndns.org> References: <20130104082751.GA22227@lizard.gateway.2wire.net> <1357288152-23625-1-git-send-email-anton.vorontsov@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1357288152-23625-1-git-send-email-anton.vorontsov@linaro.org> Sender: owner-linux-mm@kvack.org List-ID: To: Anton Vorontsov Cc: David Rientjes , Pekka Enberg , Mel Gorman , Glauber Costa , Michal Hocko , "Kirill A. Shutemov" , Luiz Capitulino , Andrew Morton , Greg Thelen , Leonid Moiseichuk , KOSAKI Motohiro , Minchan Kim , Bartlomiej Zolnierkiewicz , John Stultz , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linaro-kernel@lists.linaro.org, patches@linaro.org, kernel-team@android.com Hello, Can you please cc me too when posting further patches? I kinda missed the whole discussion upto this point. On Fri, Jan 04, 2013 at 12:29:11AM -0800, Anton Vorontsov wrote: > This commit implements David Rientjes' idea of mempressure cgroup. > > The main characteristics are the same to what I've tried to add to vmevent > API; internally, it uses Mel Gorman's idea of scanned/reclaimed ratio for > pressure index calculation. But we don't expose the index to the userland. > Instead, there are three levels of the pressure: > > o low (just reclaiming, e.g. caches are draining); > o medium (allocation cost becomes high, e.g. swapping); > o oom (about to oom very soon). > > The rationale behind exposing levels and not the raw pressure index > described here: http://lkml.org/lkml/2012/11/16/675 > > For a task it is possible to be in both cpusets, memcg and mempressure > cgroups, so by rearranging the tasks it is possible to watch a specific > pressure (i.e. caused by cpuset and/or memcg). So, cgroup is headed towards single hierarchy. Dunno how much it would affect mempressure but it probably isn't wise to design with focus on multiple hierarchies. Isn't memory reclaim and oom condition tied to memcgs when memcg is in use? It seems natural to tie mempressure to memcg. Is there some reason this should be a separate cgroup. I'm kinda worried this is headed cpuacct / cpu silliness we have. Glauber, what's your opinion here? Thanks. -- tejun -- 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