CPU spike when I quit rails

Hi -

I'm new to rails, not so new to Ruby (though by no means any sort of wizard; just use it for real projects at school.) I've coded up a pretty simple rails app to run an experiment. Very standard, nothing tricky.

Everything is fine - the app runs fine, performance is fine (although I am not stressing the system at all with the app) - until it's time to quit. I do this on the command line, in the terminal where I've executed "ruby script/server". I type control-c to interrupt the process. And here's where it gets weird - I get:

^C** INT signal received. Exiting

And then it hangs. My CPU load goes to 100%, and it stays pegged until I kill the process via kill -9 in another terminal window.

I realize this is a hard question to answer without seeing my code, but maybe someone has a pointer for how I myself could go about answering it? How I could find out what ruby/rails is doing after I press control-c to peg the CPU? Maybe I could run it via JRuby and Netbeans, or something?

Ideas or pointers are much appreciated.