I work for Cornell Information Technologies, so I can tell you precisely what goes on during CoursEnroll. First, the "Salsa server" (the one that gives you messages with the jalepeño pepper) authenticates who you are and gets the process rolling. In past years, this was the bottleneck, as literally thousands of students were hammering away at the Salsa server simultaneously.

This year, the second part of CoursEnroll is slow. Once you get into Just The Facts (Cornell's main student services application), your computer starts sending its requests to KFront, an app sitting on the mainframe. KFront then sends the request to 20 or so dispatchers which complete the request. A request takes 1/4 of a second to fufill. The problem is that with thousands of people using the system simulatenously, some kind of powerful queueing system is needed. KFront has limited queueing ability, but most requests time out before they can be fulfilled. Exacerbating the problem are the hundreds of students continually clicking the buttons in Just The Facts, thinking that this will get them their classes faster.

During this past CoursEnroll period, it was three hours of continuous reuqesting before I got a single class. CIT is aware that this sucks, but until the registar's office updates their ancient student database to something more workable, we're probably stuck with the slowness. What you can do is suggest a better interface: the new Java one is worse than last year's crummy Hypercard-based GUI.

It's not really the servers being jammed -- or even the mainframe's processor. It's just that the applications running on the mainframe are flooded beyond their ability.