From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail190.messagelabs.com (mail190.messagelabs.com [216.82.249.51]) by kanga.kvack.org (Postfix) with SMTP id 5B3AE8D0040 for ; Wed, 23 Mar 2011 10:26:50 -0400 (EDT) Date: Wed, 23 Mar 2011 15:26:45 +0100 From: Michal Hocko Subject: Re: cgroup: real meaning of memory.usage_in_bytes Message-ID: <20110323142645.GB15474@tiehlicka.suse.cz> References: <20110318152532.GB18450@tiehlicka.suse.cz> <20110321093419.GA26047@tiehlicka.suse.cz> <20110322073514.GB12940@tiehlicka.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: To: Ying Han Cc: KAMEZAWA Hiroyuki , Daisuke Nishimura , Andrew Morton , linux-mm@kvack.org, LKML On Tue 22-03-11 10:06:27, Ying Han wrote: > On Tue, Mar 22, 2011 at 12:35 AM, Michal Hocko wrote: > > On Mon 21-03-11 10:22:41, Ying Han wrote: > > [...] > >> > >> Michal, > >> > >> Can you help to post the test result after applying the patch? > > > > The result of the LTP test is: > > TEST 4: MEMORY CONTROLLER TESTING > > RUNNING SETUP..... > > WARN:/dev/memctl already exist..overwriting > > Cleanup called > > TEST STARTED: Please avoid using system while this test executes > > memory usage from memory.usage_in_bytes= 62955520 > > memory usage from memory.stat= 62955520 > > TINFO ? Memory Resource Controller: stat check test passes first run > > Test continues to run the second step. > > memory usage from memory.usage_in_bytes= 78643200 > > memory usage from memory.stat=78643200 > > TPASS ? Memory Resource Controller: stat check test PASSED > > Memory Resource Controller test executed successfully. > > Cleanup called [...] > Thanks Michal for fixing it up. Regardless of the performance > overhead, the change make sense to me. As you can see in the other email in this thread the patch is not 100% correct because it doesn't consider batched uncharges which are stored in the task_struct. Make it 100% correct would be harder and probably not worth the overhead. Daisuke Nishimura is working on the documentation update patch which will most likely describe that usage_in_bytes is not exactly rss+cache and that nobody should rely on it. -- Michal Hocko SUSE Labs SUSE LINUX s.r.o. Lihovarska 1060/12 190 00 Praha 9 Czech Republic -- 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