From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx108.postini.com [74.125.245.108]) by kanga.kvack.org (Postfix) with SMTP id 627956B004D for ; Tue, 15 May 2012 20:03:21 -0400 (EDT) Received: from m1.gw.fujitsu.co.jp (unknown [10.0.50.71]) by fgwmail5.fujitsu.co.jp (Postfix) with ESMTP id 5A4FB3EE0BD for ; Wed, 16 May 2012 09:03:19 +0900 (JST) Received: from smail (m1 [127.0.0.1]) by outgoing.m1.gw.fujitsu.co.jp (Postfix) with ESMTP id 40C0D45DE5B for ; Wed, 16 May 2012 09:03:19 +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 288E945DE5A for ; Wed, 16 May 2012 09:03:19 +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 187CA1DB803A for ; Wed, 16 May 2012 09:03:19 +0900 (JST) Received: from m1000.s.css.fujitsu.com (m1000.s.css.fujitsu.com [10.240.81.136]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id C510E1DB8045 for ; Wed, 16 May 2012 09:03:18 +0900 (JST) Message-ID: <4FB2EE59.8070505@jp.fujitsu.com> Date: Wed, 16 May 2012 09:01:29 +0900 From: KAMEZAWA Hiroyuki MIME-Version: 1.0 Subject: Re: [patch 0/6] mm: memcg: statistics implementation cleanups References: <1337018451-27359-1-git-send-email-hannes@cmpxchg.org> <4FB1A115.2080303@jp.fujitsu.com> <20120515110302.GH1406@cmpxchg.org> In-Reply-To: <20120515110302.GH1406@cmpxchg.org> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Johannes Weiner Cc: Andrew Morton , Michal Hocko , cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org (2012/05/15 20:03), Johannes Weiner wrote: > On Tue, May 15, 2012 at 09:19:33AM +0900, KAMEZAWA Hiroyuki wrote: >> (2012/05/15 3:00), Johannes Weiner wrote: >> >>> Before piling more things (reclaim stats) on top of the current mess, >>> I thought it'd be better to clean up a bit. >>> >>> The biggest change is printing statistics directly from live counters, >>> it has always been annoying to declare a new counter in two separate >>> enums and corresponding name string arrays. After this series we are >>> down to one of each. >>> >>> mm/memcontrol.c | 223 +++++++++++++++++------------------------------ >>> 1 file changed, 82 insertions(+), 141 deletions(-) >> >> to all 1-6. Thank you. >> >> Acked-by: KAMEZAWA Hiroyuki > > Thanks! > >> One excuse for my old implementation of mem_cgroup_get_total_stat(), >> which is fixed in patch 6, is that I thought it's better to touch all counters >> in a cachineline at once and avoiding long distance for-each loop. >> >> What number of performance difference with some big hierarchy(100+children) tree ? >> (But I agree your code is cleaner. I'm just curious.) > > I set up a parental group with hierarchy enabled, then created 512 > children and did a 4-job kernel bench in one of them. Every 0.1 > seconds, I read the stats of the parent, which requires reading each > stat/event/lru item from 512 groups before moving to the next one: > > 512stats-vanilla 512stats-patched > Walltime (s) 62.61 ( +0.00%) 62.88 ( +0.43%) > Walltime (stddev) 0.17 ( +0.00%) 0.14 ( -3.17%) > > That should be acceptable, I think. > > Yes, thank you. 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 internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org