Chplvis: A Communication and Task Visualization Tool for Chapel

Tasks and locales are the two primary abstractions in Chapel, tasks for parallelism and locales for data and execution locality. Chapel contains constructs that implicitly or explicitly specify tasks and inter-locale communication. When writing Chapel programs, it is sometimes difficult, especially for new Chapel programmers, to know how tasks and inter-locale communication are generated by the program. We present a new tool, chplvis, that visually presents to a programmer this important information.