[p_l]

It was an early AVX-512 unit that resulted in down lock when you used more than a few instructions in short time, as well as resulted in a Linus rant.

Later CPUs (updated skylake xeons and later, AMD Zen 4 and newer) don't have the issue

[e4m2]

Historically, it was a bit more complex than that, and applies to more than just AVX-512: https://gist.github.com/rygorous/32bc3ea8301dba09358fd2c64e0....

[p_l]

Fun! in Dwarf Fortress way :)

Thanks for the deeper dive