Summary: Cache miss problems. His approach to solve it is first to move decision data up in the tree to prevent walking into every child node, and second reorga

Summary: Cache miss problems. His approach to solve it is first to move decision data up in the tree to prevent walking into every child node, and second reorganizing nested loops to improve locality. His loops probably can be improved further unless the missing bits (he only gives pseudo-code) are a limit. There's mention of Oprofile, something I didn't knew existed. It looks like a very nice complement for Valgrind (Cachegrind in this scenario.) Yay!