On 04/26/2016 12:33 PM, Mel Gorman wrote:
I dithered on this a bit and could not convince myself that the order case really is unlikely. It depends on the situation as we could be tearing down a large THP-backed mapping. SLUB is also using compound pages so it's both workload and configuration dependent whether this path is really likely or not.
Hmm I see. But e.g. buffered_rmqueue uses "if (likely(order == 0))" so it would be at least consistent. Also compound pages can amortize the extra cost over more base pages.

