In the late '90s, I was working for CMU as a programmer and general-purpose janitor for the Andrew system, the campus computing environment. Students frequently

In the late '90s, I was working for CMU as a programmer and general-purpose janitor for the Andrew system, the campus computing environment. Students frequently worked on a pool of shared machines, particularly for a class like Operating Systems that required Unix. (Yalnix did not run on Linux at the time.) The shared machines had no per-user quota, and generally, abuse wasn't a problem. But one semester, the OS class added a new first assignment: write a shell. It took about a day or two, but after the second or third accidental fork bomb, a generous per-user process limit was imposed.