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I'm not going to dispute that but just want to highlight it doesn't change the fact that committed RAM can show as extremely high just by working with memory mapped files.

Memory mapping a GB log file for example will absolutely show GB's of committed memory but in reality you'll only have the last page in actual physical RAM.

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Right. When you memory-map a file, what you've essentially done is add a temporary new pagefile to the system (your mapped file), and when you work with memory backed by that file, it's no different from working with "anonymous" memory backed by the system-wide pagefile.

Aside: I have to say this is a genius perspective on mmap, and I now finally understand why the same syscall is used for both. I never understood the link.

Thank you.

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