[PATCH 01/10] mm: Introduce the memory regions data structure

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

Hi Dave,

On Fri, May 27, 2011 at 02:31:52PM -0700, Dave Hansen wrote:
> On Fri, 2011-05-27 at 23:50 +0530, Vaidyanathan Srinivasan wrote:
> > The overall idea is to have a VM data structure that can capture
> > various boundaries of memory, and enable the allocations and reclaim
> > logic to target certain areas based on the boundaries and properties
> > required. 
> 
> It's worth noting that we already do targeted reclaim on boundaries
> other than zones.  The lumpy reclaim and memory compaction logically do
> the same thing.  So, it's at least possible to do this without having
> the global LRU designed around the way you want to reclaim.
>

My understanding maybe incorrect, but doesn't both lumpy reclaim and
memory compaction still work under zone boundary ? While trying to free
up higher order pages, lumpy reclaim checks to ensure that pages that
are selected do not cross zone boundary. Further, compaction walks
through the pages in a zone and tries to re-arrange them.
 
> Also, if you get _too_ dependent on the global LRU, what are you going
> to do if our cgroup buddies manage to get cgroup'd pages off the global
> LRU?  
> 

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