Linux 5.0 to Linux 5.9 Kernel Benchmarking Was a Bumpy Ride with New Regressions

Interesting that a small tidy up from Linus directly caused such an impact on Redis/Apache.

> That Apache regression was tracked down to a Linux 5.9 change by Linus Torvalds himself. He took up rewriting the wait_on_page_bit_common() logic.