Parallel Graph Reduction with the h ; Gi - machine

We have implemented a parallel graph reducer on a commercially available shared memory multiprocessor (a Sequent Symmetry TM ), that achieves real speedup compared to a a fast compiled implementation of the conventional Gmachine. Using 15 processors, this speedup ranges between 5 and 11, depending on the program. Underlying the implementation is an abstract machine called the h ; Gi-machine. We describe the sequential and the parallel h ; Gi-machine, and our implementation of them. We provide performance and speedup gures and graphs.