May add, if you mmap(2) a memory segment (even a very large one, say 1Tb), nothi... | Hacker News

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		aduitsis on Nov 28, 2017 \| parent \| context \| favorite \| on: Disable transparent hugepages May add, if you mmap(2) a memory segment (even a very large one, say 1Tb), nothing happens with regard to page mapping. It is not uncommon to see java tomcat processes allocating north of 80 Gb. But only a small percentage of these is actually used.

loeg on Nov 28, 2017 [–]

Well, the page tables are initialized. Those aren't totally free, especially if a large mapping uses 4k pages.

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