Trace visualization is a way to understand the behavior of an application on computer systems. In this paper we describe the design and implementation of a Gantt Chart visualization tool for visualizing multi-dimensional trace files, particularly traces from Message Passing Interface (MPI) programs and Apache servers. An MPI tracing library is developed for MPI programs, and a Apache server plug-in is developed to generate web traces. Since the amount of trace data may be large, utilities are provided to convert and merge multiple event trace files into one scalable, self-defining interval file for visualization. The interval format facilitates the development of multiple time-space diagrams for visualization tools. For MPI traces, each record also includes an instruction address for source code association, which provides a way to display the source code and pin-point the line that generates the event.