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Date: Thu, 26 Aug 2010 03:49:00 +0200
From: =?utf-8?B?TWljaGHFgiBOYXphcmV3aWN6?= <m.nazarewicz@samsung.com>
Subject: Re: [PATCH/RFCv4 0/6] The Contiguous Memory Allocator framework
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On Thu, 26 Aug 2010 01:31:25 +0200, Jonathan Corbet <corbet@lwn.net> wro=
te:
> The original OLPC has a camera controller which requires three contigu=
ous,
> image-sized buffers in memory.  That system is a little memory constra=
ined
> (OK, it's desperately short of memory), so, in the past, the chances o=
f
> being able to allocate those buffers anytime some kid decides to start=

> taking pictures was poor.  Thus, cafe_ccic.c has an option to snag the=

> memory at initialization time and never let go even if you threaten it=
s
> family.  Hell hath no fury like a little kid whose new toy^W education=
al
> tool stops taking pictures.
>
> That, of course, is not a hugely efficient use of memory on a
> memory-constrained system.  If the VM could reliably satisfy those
> allocation requestss, life would be wonderful.  Seems difficult.  But =
it
> would be a nicer solution than CMA, which, to a great extent, is reall=
y
> just a standardized mechanism for grabbing memory and never letting go=