Building Medley Interlisp from source has been dramatically faster since the past week or so: it now takes 1/3 of what it used to. I didn't modify the setup of my Linux Mint 22.1 Cinnamon box other than the usual system updates, and there were no recent major performance related changes to Medley.
I'm really happy but wonder about the source of the speedup. Perhaps some Linux kernel tweaks but my Mint release doesn't incorporate the bleeding edge.