From time to time I still miss turbo button and a (functioning) pause key. On DOS you could pause execution to inspect output... I guess with multiprocessing it became more difficult to implement this...

  pkill -STOP "$(xprop _NET_WM_PID)"
  pkill -CONT "$(xprop _NET_WM_PID)"

This might have some unintended consequences though (file locks, clock drift between running program and your quartz...).

Regarding turbo, I'm pretty sure a shell script could set the CPU's speed governor to "conservative" at the press of a button.

ars

You can also use the cpulimit program to do that.

https://github.com/opsengine/cpulimit