From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx126.postini.com [74.125.245.126]) by kanga.kvack.org (Postfix) with SMTP id 37C3A6B004D for ; Thu, 5 Jan 2012 08:03:16 -0500 (EST) From: Subject: RE: [PATCH 3.2.0-rc1 0/3] Used Memory Meter pseudo-device and related changes in MM Date: Thu, 5 Jan 2012 13:02:23 +0000 Message-ID: <84FF21A720B0874AA94B46D76DB9826904554391@008-AM1MPN1-003.mgdnok.nokia.com> References: <20120104195612.GB19181@suse.de> <84FF21A720B0874AA94B46D76DB98269045542B5@008-AM1MPN1-003.mgdnok.nokia.com> In-Reply-To: Content-Language: en-US Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Sender: owner-linux-mm@kvack.org List-ID: To: penberg@kernel.org Cc: gregkh@suse.de, linux-mm@kvack.org, linux-kernel@vger.kernel.org, cesarb@cesarb.net, kamezawa.hiroyu@jp.fujitsu.com, emunson@mgebm.net, aarcange@redhat.com, riel@redhat.com, mel@csn.ul.ie, rientjes@google.com, dima@android.com, rebecca@android.com, san@google.com, akpm@linux-foundation.org, vesa.jaaskelainen@nokia.com Well, mm/notify.c seems a bit global for me. At the first step I handle inp= uts from Greg and try to find less destructive approach to allocation track= ing rather than page_alloc. The issue is I know quite well my problem, so other guys who needs memory t= racking has own requirements how account memory, how often notify/which gra= nularity, =20 how many clients could be and so one. If I get some inputs I will be happy= to implement them. With Best Wishes, Leonid -----Original Message----- From: penberg@gmail.com [mailto:penberg@gmail.com] On Behalf Of ext Pekka E= nberg Sent: 05 January, 2012 14:41 To: Moiseichuk Leonid (Nokia-MP/Helsinki) Cc: gregkh@suse.de; linux-mm@kvack.org; linux-kernel@vger.kernel.org; cesar= b@cesarb.net; kamezawa.hiroyu@jp.fujitsu.com; emunson@mgebm.net; aarcange@r= edhat.com; riel@redhat.com; mel@csn.ul.ie; rientjes@google.com; dima@androi= d.com; rebecca@android.com; san@google.com; akpm@linux-foundation.org; Jaas= kelainen Vesa (Nokia-MP/Helsinki) Subject: Re: [PATCH 3.2.0-rc1 0/3] Used Memory Meter pseudo-device and rela= ted changes in MM On Thu, Jan 5, 2012 at 1:47 PM, wrote: > As I understand AOOM it wait until situation is reached bad conditions=20 > which required memory reclaiming, selects application according to=20 > free memory and oom_adj level and kills it. So no intermediate levels co= uld be checked (e.g. > 75% usage), nothing could be done in user-space to prevent killing,=20 > no notification for case when memory becomes OK. > > What I try to do is to get notification in any application that memory=20 > becomes low, and do something about it like stop processing data,=20 > close unused pages or correctly shuts applications, daemons. =20 > Application(s) might have necessity to install several notification=20 > levels, so reaction could be adjusted based on current utilization=20 > level per each application, not globally. Sure. However, from VM point of view, both have the exact same functionality: detect when we reach low memory condition (for some configur= able threshold) and notify userspace or kernel subsystem about it. That's the part I'd like to see implemented in mm/notify.c or similar. I really don't care what Android or any other folks use it for exactly as l= ong as the generic code is light-weight, clean, and we can reasonably assum= e that distros can actually enable it. -- 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