I am slowly catching up with this thread. On Fri 19-02-21 09:20:16, David Hildenbrand wrote: [...] > So if we have zero, we write zero. We'll COW pages, triggering a write fault > - and that's the only good thing about it. For example, similar to > MADV_POPULATE, nothing stops KSM from merging anonymous pages again. So for > anonymous memory the actual write is not helpful at all. Similarly for > hugetlbfs, the actual write is not necessary - but there is no other way to > really achieve the goal. I really do not see why you care about KSM so much. Isn't KSM an explicit opt-in with a fine grained interface to control which memory to KSM or not? -- Michal Hocko SUSE Labs