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 C9ECE6B008C for ; Wed, 10 Mar 2010 20:21:10 -0500 (EST) Received: from m1.gw.fujitsu.co.jp ([10.0.50.71]) by fgwmail7.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id o2B1L8LC013319 for (envelope-from kamezawa.hiroyu@jp.fujitsu.com); Thu, 11 Mar 2010 10:21:08 +0900 Received: from smail (m1 [127.0.0.1]) by outgoing.m1.gw.fujitsu.co.jp (Postfix) with ESMTP id E599D45DE51 for ; Thu, 11 Mar 2010 10:21:07 +0900 (JST) Received: from s1.gw.fujitsu.co.jp (s1.gw.fujitsu.co.jp [10.0.50.91]) by m1.gw.fujitsu.co.jp (Postfix) with ESMTP id C522545DE4E for ; Thu, 11 Mar 2010 10:21:07 +0900 (JST) Received: from s1.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id A79B31DB8047 for ; Thu, 11 Mar 2010 10:21:07 +0900 (JST) Received: from ml13.s.css.fujitsu.com (ml13.s.css.fujitsu.com [10.249.87.103]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id 500161DB804A for ; Thu, 11 Mar 2010 10:21:07 +0900 (JST) Date: Thu, 11 Mar 2010 10:17:26 +0900 From: KAMEZAWA Hiroyuki Subject: Re: [PATCH -mmotm 0/5] memcg: per cgroup dirty limit (v6) Message-Id: <20100311101726.f58d24e9.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20100311093913.07c9ca8a.kamezawa.hiroyu@jp.fujitsu.com> References: <1268175636-4673-1-git-send-email-arighi@develer.com> <20100311093913.07c9ca8a.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: Andrea Righi , Balbir Singh , Daisuke Nishimura , Vivek Goyal , Peter Zijlstra , Trond Myklebust , Suleiman Souhlal , Greg Thelen , "Kirill A. Shutemov" , Andrew Morton , containers@lists.linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: On Thu, 11 Mar 2010 09:39:13 +0900 KAMEZAWA Hiroyuki wrote: > > The performance overhead is not so huge in both solutions, but the impact on > > performance is even more reduced using a complicated solution... > > > > Maybe we can go ahead with the simplest implementation for now and start to > > think to an alternative implementation of the page_cgroup locking and > > charge/uncharge of pages. > > > > maybe. But in this 2 years, one of our biggest concerns was the performance. > So, we do something complex in memcg. But complex-locking is , yes, complex. > Hmm..I don't want to bet we can fix locking scheme without something complex. > But overall patch set seems good (to me.) And dirty_ratio and dirty_background_ratio will give us much benefit (of performance) than we lose by small overheads. IIUC, this series affects trgger for background-write-out. Could you show some score which dirty_ratio give us benefit in the cases of - copying a file in a memcg which hits limit ex) copying a 100M file in 120MB limit. etc.. - kernel make performance in limited memcg. ex) making a kernel in 100MB limit (too large ?) etc....(when an application does many write and hits memcg's limit.) But, please get enough ack for changes in generic codes of dirty_ratio. Thank you for your work. Regards, -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