Re: [RFC PATCH] page_cgroup: Reduce allocation overhead forpage_cgroup array for CONFIG_SPARSEMEM v2

From: Michal Hocko
Date: Thu Feb 24 2011 - 08:40:55 EST

Here is the second version of the patch. I have used alloc_pages_exact
instead of the complex double array approach.

I still fallback to kmalloc/vmalloc because hotplug can happen quite
some time after boot and we can end up not having enough continuous
pages at that time.

I am also thinking whether it would make sense to introduce
alloc_pages_exact_node function which would allocate pages from the
given node.

Any thoughts?