I doubt these benchmarks are relevant anymore as Linux has a system just dedicated to copying files. So you never even have to leave the page cache, let alone

I doubt these benchmarks are relevant anymore as Linux has a system just dedicated to copying files. So you never even have to leave the page cache, let alone copy into user space. OFC it was implemented post 4.0 so I doubt GLibc supports it therefore the whole world pretends it doesn't exist.