From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail202.messagelabs.com (mail202.messagelabs.com [216.82.254.227]) by kanga.kvack.org (Postfix) with SMTP id 461E26B0092 for ; Tue, 18 Jan 2011 21:53:41 -0500 (EST) Received: from m2.gw.fujitsu.co.jp (unknown [10.0.50.72]) by fgwmail6.fujitsu.co.jp (Postfix) with ESMTP id BEE413EE0C0 for ; Wed, 19 Jan 2011 11:53:37 +0900 (JST) Received: from smail (m2 [127.0.0.1]) by outgoing.m2.gw.fujitsu.co.jp (Postfix) with ESMTP id A53D745DE6C for ; Wed, 19 Jan 2011 11:53:37 +0900 (JST) Received: from s2.gw.fujitsu.co.jp (s2.gw.fujitsu.co.jp [10.0.50.92]) by m2.gw.fujitsu.co.jp (Postfix) with ESMTP id 7FBFC45DE67 for ; Wed, 19 Jan 2011 11:53:37 +0900 (JST) Received: from s2.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s2.gw.fujitsu.co.jp (Postfix) with ESMTP id 73FA71DB8042 for ; Wed, 19 Jan 2011 11:53:37 +0900 (JST) Received: from ml13.s.css.fujitsu.com (ml13.s.css.fujitsu.com [10.249.87.103]) by s2.gw.fujitsu.co.jp (Postfix) with ESMTP id 324E71DB803E for ; Wed, 19 Jan 2011 11:53:37 +0900 (JST) Date: Wed, 19 Jan 2011 11:47:35 +0900 From: KAMEZAWA Hiroyuki Subject: Re: [PATCH 2/5] Add per cgroup reclaim watermarks. Message-Id: <20110119114735.aea5698f.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: References: <1294956035-12081-1-git-send-email-yinghan@google.com> <1294956035-12081-3-git-send-email-yinghan@google.com> <20110114091119.2f11b3b9.kamezawa.hiroyu@jp.fujitsu.com> <20110119095650.02db87e0.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: David Rientjes Cc: Ying Han , Balbir Singh , Daisuke Nishimura , Andrew Morton , Mel Gorman , Johannes Weiner , Christoph Lameter , Wu Fengguang , Andi Kleen , Hugh Dickins , Rik van Riel , KOSAKI Motohiro , Tejun Heo , linux-mm@kvack.org List-ID: On Tue, 18 Jan 2011 18:38:42 -0800 (PST) David Rientjes wrote: > On Wed, 19 Jan 2011, KAMEZAWA Hiroyuki wrote: > > > > so something like per-memcg min_wmark which also needs to be reserved upfront? > > > > > > > I think the variable name 'min_free_kbytes' is the source of confusion... > > It's just a watermark to trigger background reclaim. It's not reservation. > > > > min_free_kbytes alters the min watermark of zones, meaning it can increase > or decrease the amount of memory that is reserved for GFP_ATOMIC > allocations, those in irq context, etc. Since oom killed tasks don't > allocate from any watermark, it also can increase or decrease the amount > of memory available to oom killed tasks. In that case, it _is_ a > reservation of memory. > I know. THIS PATCH's min_free_kbytes is not the same to ZONE's one. It's just a trigger. This patch's one is not used to limit charge() or for handling gfp_mask. (We can assume it's always GFP_HIGHUSER_MOVABLE or GFP_USER in some cases.) So, I wrote the name of 'min_free_kbytes' in _this_ patch is a source of confusion. I don't recommend to use such name in _this_ patch. 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/ . Fight unfair telecom policy in Canada: sign http://dissolvethecrtc.ca/ Don't email: email@kvack.org