Found it! Perl Optimization Tidbits by Daina Petit at 27:03 mark. The link is to that spot in the video.
My OS is Debian 10 (Buster); my perl versions are 5.28.1 local and 5.16.3 or 5.30.0 on web host depending on the shebang.
No matter how hysterical I get, my problems are not time sensitive. So, relax, have a cookie, and a very nice day!