Visualizing PVM Executions

Because of the complexity of distributed applications, understanding their behaviour is a challenging task. Frequently, tools that provide graphical visualizations based on process-time diagrams are provided to facilitate this understanding task. While a wide variety of such tools exist, few address the complexity problem directly. In contrast, our research has focused on the problem of visualizing complex distributed executions. Our visualization tool, Poet, provides abstraction facilities in both the process and time dimension to reduce the apparent complexity of a distributed execution. Because of its emphasis on target-system independence, adapting Poet for PVM 3.3, utilizing the tracing facility provided in this version of PVM, was relatively straightforward. This paper summarizes the necessary steps to adapt Poet to PVM and presents a few simple visualizations. We also discuss the use of event abstraction to provide execution visualizations that match the programming model provided by PVM, in particular with respect to group-communication primitives.