For a complex system, tracking down a failure in log files can be a real challenge. Tarbox helps maintain a program that writes 100,000 lines of code an hour. He told of spreading a log printout across the floor and mapping cause and effect statements for hours to get to the root of a memory link. He decided to bring hearing as well as vision to bear on log files by combining Log4J and JFugue, and Log4JFugue was born.

Tarbox "played" a log file for the audience in which log messages were represented by percussion instruments: successful events were represented by drum sounds, failures were represented by cymbal crashes, and so on. The result sounded like an elaborate mechanism ticking along, and it was easy to tell when the system was getting into trouble by
the sound of the cymbals. Tarbox likened it to the way a good mechanic can tell the condition of a car by the sound of its engine. The timing of repeated rhythmic motifs indicated the frequency of certain function calls, and in this way he got an intuitive sense of how the system was performing.