Tau - Tuning and Analysis Utilities for Portable Parallel Programming

Introduction Most users find parallel programming difficult for at least four reasons. First, parallel computing abstractions (e.g., data parallelism, control or task parallelism, producer/consumer parallelism) are diverse, differing mainly by the type of parallel behavior supported (or allowed) in a program's execution. In addition to learning the parallel programming languages and tools in a particular environment, a user must decide which parallel computing model provides the "best" execution for their problem. Deciding how to choose between models often requires a sophisticated understanding of the application, its underlying algorithms, the expressiveness of the language used, and effects of the system software and hardware architecture of the parallel machine. Unfortunately, this choice is complicated by the fact that not all parallel computing abstractions are equally well supported in existing programming systems. Second, most parallel programming systems do not insul