On Monday 04 July 2011, Ankita Garg wrote:

quoted

It still sounds to me that this can be done using the NUMA properties
that Linux already understands, and teaching more subsystems about it,
but maybe the memory hotplug developers have already come up with
another scheme. The way that memory hotplug and CMA choose their
memory regions certainly needs to take both into account. As far as
I can see there are both conflicting and synergistic effects when
you combine the two.

Recently, we proposed a generic 'memory regions' framework to exploit
the memory power management capabilities on the embedded boards. Think
of some of the above CMA requirements could be met by this fraemwork.
One of the main goals of regions is to make the VM aware of the hardware
memory boundaries, like bank. For managing memory power consumption,
memory regions are created aligned to the hardware granularity at which
the power can be managed (ie, the memory power consumption operations
like on/off can be performed). If attributed are associated with each of
these regions, some of these regions could be marked as CMA-only,
ensuring that only movable and per-bank memory is allocated. More
details on the design can be found here:

http://lkml.org/lkml/2011/5/27/177
http://lkml.org/lkml/2011/6/29/202
http://lwn.net/Articles/446493/

Thanks for the pointers, that is exactly what I was looking for.

	Arnd