Portability and reliability of parallel programs can be severely impaired by their nondeterministic behavior. Therefore, an effective means to precisely and accurately specify unacceptable nondeterministic behavior is necessary for testing and debugging parallel programs. In this paper, we describe a class of expressions called Message Expressions that can be used to specify nondeterministic behavior of message passing parallel programs. Specification of program behavior with Message Expressions is easier than pattern based specification techniques in that the former does not require knowledge of run-time event order, whereas that later depends on the user's knowledge of the run-time event order for correct specification. We also discuss our adaptation of Message Expressions for use in a dynamic distributed testing and debugging tool, called mdb, for programs written for PVM (Parallel Virtual Machine).
展开▼
