Re: [PATCH 1/5] mm: Add support for unaccepted memory

[Andi Kleen]

> So, this is right in the fast path of the page allocator.  It's a
> one-time thing per 2M page, so it's not permanent.
>
> *But* there's both a global spinlock and a firmware call hidden in
> clear_page_offline().  That's *GOT* to hurt if you were, for instance,
> running a benchmark while this code path is being tickled.  Not just to
>
> That could be just downright catastrophic for scalability, albeit
> temporarily

This would be only a short blib at initialization until the system 
reaches steady state. So yes it would be temporary, but very short at that.

-Andi