An Efficient Debugging Method for Message-based Parallel Programs using Static Analysis Information

Guaranteeiq reproducibility and minimizing probe effects are major issues in the parallel program debugging. This paper suggests a new debugging method, named Detect and Reproduce method, for messagebased parallel programs. The proposed method is designed to guarantee the reproducible behaviors of a target program and to alleviate probe effects by reducing both the number of the probes to be inserted into a program and the amount of information gathered by those probes. The proposed method achieves such effects by employing a static analysis technique t o detect nondeterm,inacy. By detecting nondeterminacy before running the program, only a small number of probes are required to assure reproducibility. To analyze messagebased programs statically, an MHB(Minima1 Happened Before) model is designed to catch the synch,ronization structures and algorithms have been developed to locate nondeterminacy based on the MHB model. Utilizing the analysis results, probes are inserted only into the places where nondeterminacy is likely to take place.