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Date: Tue, 05 Jun 2012 17:00:14 +0900
From: Minchan Kim <minchan@kernel.org>
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To: Pekka Enberg <penberg@kernel.org>
CC: Anton Vorontsov <cbouatmailru@gmail.com>,
        KOSAKI Motohiro <kosaki.motohiro@gmail.com>,
        Leonid Moiseichuk <leonid.moiseichuk@nokia.com>,
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        patches@linaro.org, kernel-team@android.com
Subject: Re: [PATCH 0/5] Some vmevent fixes...
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Hi Peakk,

On 06/05/2012 04:53 PM, Pekka Enberg wrote:

> On Mon, Jun 4, 2012 at 4:35 PM, Anton Vorontsov <cbouatmailru@gmail.com> wrote:
>>> I don't mean VMEVENT_ATTR_LOWMEM_PAGES but following as,
>>>
>>> VMEVENT_ATTR_NR_FREE_PAGES
>>> VMEVENT_ATTR_NR_SWAP_PAGES
>>> VMEVENT_ATTR_NR_AVAIL_PAGES
>>>
>>> I'm not sure how it is useful.
>>
>> Yep, these raw values are mostly useless, and personally I don't use
>> these plain attributes. I use heuristics, i.e. "blended" attributes.
>> If we can come up with levels-based approach w/o using vmstat, well..
>> OK then.
> 
> That's what Nokia's lowmem notifier uses. We can probably drop them
> once we have something else they could use.


Next concern is that periodic timer of implementation.
I think it would add direct hook in vmscan.c rather than peeking raw vmstat periodically by timer
so we can control more fine-grained way without unnecessary overhead.

-- 
Kind regards,
Minchan Kim