On Sun, 16 Sep 2007, Jörn Engel wrote: > I bet! My (false) assumption was the same as Goswin's. If non-movable > pages are clearly seperated from movable ones and will evict movable > ones before polluting further mixed superpages, Nick's scenario would be > nearly infinitely impossible. > > Assumption doesn't reflect current code. Enforcing this assumption > would cost extra overhead. The amount of effort to make Christoph's > approach work reliably seems substantial and I have no idea whether it > would be worth it. My approach is based on Mel's code and is already working the way you describe. Page cache allocs are marked __GFP_MOVABLE by Mel's work.