[PATCH 00/10] mm: Linux VM Infrastructure to support Memory Power Management

[ankita@in.ibm.com (Ankita Garg)]

Hi,

On Fri, Jun 10, 2011 at 08:02:33PM -0700, Arjan van de Ven wrote:
> On Fri, 10 Jun 2011 12:37:13 -0700
> "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> wrote:
> 
> > On Fri, Jun 10, 2011 at 08:23:29PM +0100, Matthew Garrett wrote:
> > > On Fri, Jun 10, 2011 at 11:47:38AM -0700, Paul E. McKenney wrote:
> > > 
> > > > And if I understand you correctly, then the patches that Ankita
> > > > posted should help your self-refresh case, along with the
> > > > originally intended the power-down case and special-purpose use
> > > > of memory case.
> > > 
> > > Yeah, I'd hope so once we actually have capable hardware.
> > 
> > Cool!!!
> > 
> > So Ankita's patchset might be useful to you at some point, then.
> > 
> > Does it look like a reasonable implementation?
> 
> as someone who is working on hardware that is PASR capable right now,
> I have to admit that our plan was to just hook into the buddy allocator,
> and use PASR on the top level of buddy (eg PASR off blocks that are
> free there, and PASR them back on once an allocation required the block
> to be broken up)..... that looked the very most simple to me.
> 

The maximum order in buddy allocator is by default 1k pages. Isn't this
too small a granularity to track blocks that might comprise a PASR unit? 

> Maybe something much more elaborate is needed, but I didn't see why so
> far.
> 
> 

-- 
Regards,
Ankita Garg (ankita at in.ibm.com)
Linux Technology Center
IBM India Systems & Technology Labs,
Bangalore, India