From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail191.messagelabs.com (mail191.messagelabs.com [216.82.242.19]) by kanga.kvack.org (Postfix) with SMTP id 3DDC36B005D for ; Sun, 9 Aug 2009 20:45:35 -0400 (EDT) Received: from m5.gw.fujitsu.co.jp ([10.0.50.75]) by fgwmail7.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id n7A0jb02021472 for (envelope-from kamezawa.hiroyu@jp.fujitsu.com); Mon, 10 Aug 2009 09:45:37 +0900 Received: from smail (m5 [127.0.0.1]) by outgoing.m5.gw.fujitsu.co.jp (Postfix) with ESMTP id 7E18645DE4C for ; Mon, 10 Aug 2009 09:45:36 +0900 (JST) Received: from s5.gw.fujitsu.co.jp (s5.gw.fujitsu.co.jp [10.0.50.95]) by m5.gw.fujitsu.co.jp (Postfix) with ESMTP id 4DB7045DE52 for ; Mon, 10 Aug 2009 09:45:36 +0900 (JST) Received: from s5.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s5.gw.fujitsu.co.jp (Postfix) with ESMTP id BA84BE1800A for ; Mon, 10 Aug 2009 09:45:35 +0900 (JST) Received: from m108.s.css.fujitsu.com (m108.s.css.fujitsu.com [10.249.87.108]) by s5.gw.fujitsu.co.jp (Postfix) with ESMTP id 646D21DB803F for ; Mon, 10 Aug 2009 09:45:35 +0900 (JST) Date: Mon, 10 Aug 2009 09:43:44 +0900 From: KAMEZAWA Hiroyuki Subject: Re: Help Resource Counters Scale Better (v3) Message-Id: <20090810094344.77a8ef55.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20090810093229.10db7185.kamezawa.hiroyu@jp.fujitsu.com> References: <20090807221238.GJ9686@balbir.in.ibm.com> <39eafe409b85053081e9c6826005bb06.squirrel@webmail-b.css.fujitsu.com> <20090808060531.GL9686@balbir.in.ibm.com> <99f2a13990d68c34c76c33581949aefd.squirrel@webmail-b.css.fujitsu.com> <20090809121530.GA5833@balbir.in.ibm.com> <20090810093229.10db7185.kamezawa.hiroyu@jp.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: KAMEZAWA Hiroyuki Cc: balbir@linux.vnet.ibm.com, Andrew Morton , andi.kleen@intel.com, Prarit Bhargava , KOSAKI Motohiro , "lizf@cn.fujitsu.com" , "menage@google.com" , Pavel Emelianov , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" List-ID: On Mon, 10 Aug 2009 09:32:29 +0900 KAMEZAWA Hiroyuki wrote: > 1. you use res_counter_read_positive() in force_empty. It seems force_empty can > go into infinite loop. plz check. (especially when some pages are freed or swapped-in > in other cpu while force_empry runs.) > > 2. In near future, we'll see 256 or 1024 cpus on a system, anyway. > Assume 1024cpu system, 64k*1024=64M is a tolerance. > Can't we calculate max-tolerane as following ? > > tolerance = min(64k * num_online_cpus(), limit_in_bytes/100); > tolerance /= num_online_cpus(); > per_cpu_tolerance = min(16k, tolelance); > > I think automatic runtine adjusting of tolerance will be finally necessary, > but above will not be very bad because we can guarantee 1% tolerance. > Sorry, one more. 3. As I requested when you pushed softlimit changes to mmotom, plz consider to implement a way to check-and-notify gadget to res_counter. See: http://marc.info/?l=linux-mm&m=124753058921677&w=2 Thanks, -Kame -- 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