Operating System Models in a Concurrent Pascal Environment: Complexity and Performance Considerations

Empirical observations of computer operating systems have shown that operating systems are designed with one of two object oriented strategies: a process or a monitor oriented approach. This paper compares the two design approaches in a Concurrent Pascal environment. Resource manager programs that are implemented in conformity with each model are evaluated using software complexity measures and program performance measures. The average complexity of resource manager processes is 94 percent larger than the average complexity of resource manager monitors. The runtime synchronization overhead of the process model program is two-eight times higher than that of its counterpart.