Program understanding is central to the development of distributed computations, from the initial coding phase, through testing and debugging, to maintenance and support. Our goal is to support programmers unfamiliar with a particular distributed computation in developing a reasonable understanding of the workings of a program, without requireing that they examine the details of the code itself. Toward, this goal, we propose query-based visualization, a novel exploratory approach to understanding distributed computations. The key features of the approach are the use of queries as a device for searching the state space, visual presentation techniques adapted from program animation, and the ability to navigate through the state space using visual interactions.
All views correspond to globally consistent snapshots of the computation.
A working prototype demonstrates the technical feasibility of the approach.