Re: [PATCH 3/3] vmevent: Implement special low-memory attribute

From: KOSAKI Motohiro <kosaki.motohiro@gmail.com>
To: Anton Vorontsov <anton.vorontsov@linaro.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@gmail.com>,
	Pekka Enberg <penberg@kernel.org>,
	Minchan Kim <minchan@kernel.org>,
	Leonid Moiseichuk <leonid.moiseichuk@nokia.com>,
	John Stultz <john.stultz@linaro.org>,
	linux-mm@kvack.org, linux-kernel@vger.kernel.org,
	linaro-kernel@lists.linaro.org, patches@linaro.org,
	kernel-team@android.com
Subject: Re: [PATCH 3/3] vmevent: Implement special low-memory attribute
Date: Tue, 08 May 2012 03:16:59 -0400	[thread overview]
Message-ID: <4FA8C86B.8010205@gmail.com> (raw)
In-Reply-To: <20120508065829.GA13357@lizard>

(5/8/12 2:58 AM), Anton Vorontsov wrote:
> On Tue, May 08, 2012 at 01:42:05AM -0400, KOSAKI Motohiro wrote:
> [...]
>>> Well, yeah, if we are to report _number of pages_, the numbers better
>>> be meaningful.
>>>
>>> That said, I think you are being unfair to Anton who's one of the few
>>> that's actually taking the time to implement this properly instead of
>>> settling for an out-of-tree hack.
>>
>> Unfair? But only I can talk about technical comment. To be honest, I
>> really dislike
>> I need say the same explanation again and again. A lot of people don't read
>> past discussion. And as far as the patches take the same mistake, I must say
>> the same thing. It is just PITA.
>
> Note that just telling people that something is PITA doesn't help solve
> things (so people will come back to you with stupid questions over and
> over again). You can call people morons, idiots and dumbasses (that's
> all fine) but still finding a way to be productive. :-)
>
> You could just give a link to a previous discussion, in which you think
> you explained all your concerns regarding cache handling issues, or
> memory notifications/statistics in general.
>
> So, feel free to call me an idiot, but please expand your points a
> little bit or give a link to the discussion you're referring to?

I don't think you are idiot. But I hope you test your patch before submitting.
That just don't work especially on x86. Because of, all x86 box have multiple zone
and summarized statistics (i.e. global_page_state() thing) don't work and can't
prevent oom nor swapping.

and please see may previous mail.