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
