Modeling and simulation of tasks interactions using graphical interface

Concurrent processes are very important to the development of modern applications, where several tasks are performed in order to accomplish a certain activity. Unfortunately, many concurrent applications, including hard real time ones, have complex interactions between tasks, which are difficult to model in order to understand or evaluate the system's behaviour by simulation. Although an accurate model for these interactions is quite desirable, most simulators do not provide this capability, representing tasks as independent black-boxes. This paper describes a graphical approach to model tasks interactions as hierarchical trees. The approach was implemented in a simulator of real-time schedulers, and the results achieved with tests over model accuracy and tool usability are presented.