FreeBSD 13 BETA Benchmarks - Performance Is Much Better
The likely explanation for the widespread performance gains would be due to the Intel hardware P-States improvements with FreeBSD 13 kernel and/or other power management improvements, but there isn't the full FreeBSD 13 change-log at this time. With the improvements being so widespread, FreeBSD likely was not taking proper advantage of Intel CPUs previously.
At first I was planning on just running some quick benchmarks on one system before becoming impressed by the performance and then tossing in a second system. From tests on other Intel hardware at least, these improvements with FreeBSD 13-BETA are widespread.
It's also not due to simply moving from LLVM Clang 10 to Clang 11 as the default compiler: workloads like Golang and OpenJDK Java are enjoying nice speed-ups too.