From: kamezawa.hiroyu@jp.fujitsu.com
Message-ID: <29463997.1213012967896.kamezawa.hiroyu@jp.fujitsu.com>
Date: Mon, 9 Jun 2008 21:02:47 +0900 (JST)
To: balbir@linux.vnet.ibm.com
Subject: Re: Re: [RFC][PATCH 1/2] memcg: res_counter hierarchy
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>, linux-mm@kvack.org,
       LKML <linux-kernel@vger.kernel.org>, menage@google.com,
       xemul@openvz.org, yamamoto@valinux.co.jp
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----- Original Message -----
way, breaks limit semantics.
>>>
>> Not easy to use in my point of view. Can we use 'share' in proper way 
>> on no-swap machine ?
>> 
>
>Not sure I understand your question. Share represents the share of available
>resources.
>

If no swap, you cannot reclaim anonymous pages and shared memory.
Then, the kernel has to abandon any kinds of auto-balancing somewhere.
(just an example. Things will be more complicated when we consinder
 mlocked pages and swap-resource-controller.)


>> yield() after callback() means that res_counter's state will be
>> far different from the state after callback.
>> So, we have to yield before call back and check res_coutner sooner.
>> 
>
>But does yield() get us any guarantees of seeing the state change?
>
Hmm, myabe my explanation is bad.

in following sequence
   1.callback()
   2.yield()
   3.check usage again
Elapsed time between 1->3 is big.

in following
   1.yield()
   2.callback()
   3.check usage again
Elapsed time between 2->3 is small.

There is an option to implement "changing limit grarually"

Thanks,
-Kame


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