Last parallel call optimization and fast backtracking in and-parallel logic programming systems
Dongxing Tang, Enrico Pontelli, Gopal Gupta, Manuel Carro · 1994
In this paper we present a novel optimization called Last Parallel Call Optimization. The last parallel call optimization can be regarded as an extension of last call optimization, found in sequential systems, to and-parallel systems. The last parallel call optimization leads to improved time and space performance for a majority of andparallel programs. The last parallel call optimization is presented in detail in this paper and its advantages discussed at length. The last parallel call optimization can be incorporated in a parallel system (such as RAPWAM) through relatively minor modifications to the runtime machinery. We also present some experimental results from a limited implementation of last parallel call operation done on the DDAS System. These experimental results prove that last parallel call optimization is indeed effective and produces better speed-ups with respect to an unoptimized implementation. We also discuss the problem of efficiently performing the kill operation in ...