From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763122AbYBMGio (ORCPT ); Wed, 13 Feb 2008 01:38:44 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753902AbYBMGid (ORCPT ); Wed, 13 Feb 2008 01:38:33 -0500 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:40974 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753499AbYBMGic (ORCPT ); Wed, 13 Feb 2008 01:38:32 -0500 Date: Wed, 13 Feb 2008 15:37:13 +0900 From: KOSAKI Motohiro To: Andrew Morton Subject: Re: [PATCH 4/8][for -mm] mem_notify v6: memory_pressure_notify() caller Cc: kosaki.motohiro@jp.fujitsu.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, marcelo@kvack.org, daniel.spang@gmail.com, riel@redhat.com, alan@lxorguk.ukuu.org.uk, linux-fsdevel@vger.kernel.org, pavel@ucw.cz, a1426z@gawab.com, jonathan@jonmasters.org, zlynx@acm.org In-Reply-To: <20080212145651.69cc34a5.akpm@linux-foundation.org> References: <2f11576a0802090724s679258c4g7414e0a6983f4706@mail.gmail.com> <20080212145651.69cc34a5.akpm@linux-foundation.org> Message-Id: <20080213152204.D894.KOSAKI.MOTOHIRO@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: Becky! ver. 2.42 [ja] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Andrew > > and, It is judged out of trouble at the fllowing situations. > > o memory pressure decrease and stop moves an anonymous page to the > > inactive list. > > o free pages increase than (pages_high+lowmem_reserve)*2. > > This seems rather arbitrary. Why choose this stage in the page > reclaimation process rather than some other stage? > > If this feature is useful then I'd expect that some applications would want > notification at different times, or at different levels of VM distress. So > this semi-randomly-chosen notification point just won't be strong enough in > real-world use. Hmmm actually, This portion become code broat through some bug reports. Yes, I think it again and implement it more simplefy. Thanks! > Does this change work correctly and appropriately for processes which are > running in a cgroup memory controller? nice point out. to be honest, I don't think at mem-cgroup until now. I will implement it at next post. > Given the amount of code which these patches add, and the subsequent > maintenance burden, and the unlikelihood of getting many applications to > actually _use_ the interface, it is not obvious to me that inclusion in the > kernel is justifiable, sorry. OK. I'll implement it again more simplefy. Thanks. > memory_pressure_notify() is far too large to be inlined. OK. I will fix it. > Some of the patches were wordwrapped. Agghh.. I will don't use gmail at next post. sorry. and, I hope merge only poll_wait_exclusive() and wake_up_locked_nr() if you don't mind. this 2 portion anybody noclaim about 2 month. and I think it is useful function by many people.