From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from m3.gw.fujitsu.co.jp ([10.0.50.73]) by fgwmail6.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id mAD1FadB021901 for (envelope-from kamezawa.hiroyu@jp.fujitsu.com); Thu, 13 Nov 2008 10:15:37 +0900 Received: from smail (m3 [127.0.0.1]) by outgoing.m3.gw.fujitsu.co.jp (Postfix) with ESMTP id AD33245DD78 for ; Thu, 13 Nov 2008 10:15:36 +0900 (JST) Received: from s3.gw.fujitsu.co.jp (s3.gw.fujitsu.co.jp [10.0.50.93]) by m3.gw.fujitsu.co.jp (Postfix) with ESMTP id 7E05845DD7A for ; Thu, 13 Nov 2008 10:15:36 +0900 (JST) Received: from s3.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s3.gw.fujitsu.co.jp (Postfix) with ESMTP id 611CB1DB803A for ; Thu, 13 Nov 2008 10:15:36 +0900 (JST) Received: from ml10.s.css.fujitsu.com (ml10.s.css.fujitsu.com [10.249.87.100]) by s3.gw.fujitsu.co.jp (Postfix) with ESMTP id D77AB1DB8040 for ; Thu, 13 Nov 2008 10:15:35 +0900 (JST) Date: Thu, 13 Nov 2008 10:13:44 +0900 From: KAMEZAWA Hiroyuki Subject: Re: [RFC][PATCH 1/6] memcg: free all at rmdir Message-Id: <20081113101344.6882c209.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20081112160758.3dca0b22.akpm@linux-foundation.org> References: <20081112122606.76051530.kamezawa.hiroyu@jp.fujitsu.com> <20081112122656.c6e56248.kamezawa.hiroyu@jp.fujitsu.com> <20081112160758.3dca0b22.akpm@linux-foundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, balbir@linux.vnet.ibm.com, nishimura@mxp.nes.nec.co.jp, menage@google.com List-ID: On Wed, 12 Nov 2008 16:07:58 -0800 Andrew Morton wrote: > On Wed, 12 Nov 2008 12:26:56 +0900 > KAMEZAWA Hiroyuki wrote: > > > +5.1 on_rmdir > > +set behavior of memcg at rmdir (Removing cgroup) default is "drop". > > + > > +5.1.1 drop > > + #echo on_rmdir drop > memory.attribute > > + This is default. All pages on the memcg will be freed. > > + If pages are locked or too busy, they will be moved up to the parent. > > + Useful when you want to drop (large) page caches used in this memcg. > > + But some of in-use page cache can be dropped by this. > > + > > +5.1.2 keep > > + #echo on_rmdir keep > memory.attribute > > + All pages on the memcg will be moved to its parent. > > + Useful when you don't want to drop page caches used in this memcg. > > + You can keep page caches from some library or DB accessed by this > > + memcg on memory. > > Would it not be more useful to implement a per-memcg version of > /proc/sys/vm/drop_caches? (One without drop_caches' locking bug, > hopefully). > > If we do this then we can make the above "keep" behaviour non-optional, > and the operator gets to choose whether or not to drop the caches > before doing the rmdir. > > Plus, we get a new per-memcg drop_caches capability. And it's a nicer > interface, and it doesn't have the obvious races which on_rmdir has, > etc. > > hm? > In my plan, I'll add memory.shrink_usage interface to do and allows #echo 0M > memory.shrink_memory_usage (you may swap tasks out if there is task..) to drop pages. Balbir, how do you think ? I've already removed "force_empty". 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