> I'm not sure which heuristics you're referring to. As I said, the details are somewhat hazy for me, but my understanding is that KSM maintains a notion of ho

> I'm not sure which heuristics you're referring to. As I said, the details are somewhat hazy for me, but my understanding is that KSM maintains a notion of how recently and how frequently a page changes, in order to determine whether it's a good candidate for deduplication or whether that would just be a waste of time that causes unnecessary page faults. I could be completely wrong on this, but I don't think it's quite as simple as "if two pages are identical, KSM de-duplicates them."