> memcpy() (ie "read()" in this case) is _always_ going to be faster in many > cases, just because it avoids all the extra complexity. While mmap() is > go

> memcpy() (ie "read()" in this case) is _always_ going to be faster in many > cases, just because it avoids all the extra complexity. While mmap() is > going to be faster in other cases. > - Linus Torvalds [0] At least a long-running db process can amortize the page table costs across many operations, unlike something ephemeral like journalctl/systemctl where it really hurts. [0] https://yarchive.net/comp/mmap.html https://yarchive.net/comp/mmap.html