Cumulating Search in a Distributed Computing Environment : A Case Study in Parallel Satis abilityHantao

We present a parallel propositional satissability (SAT) prover called PSATO for networks of workstations. PSATO is based on the sequential SAT prover SATO, which is an eecient implementation of the Davis-Putnam algorithm. The master-slave model is used for communication. A simple and eeective workload balancing method distributes the workload among workstations. A key property of our method is that the concurrent processes explore disjoint portions of the search space. In this way, we use parallelism without introducing redundant search. Our approach provides solutions to the problems of (i) cumulating intermediate results of separated runs of reasoning programs; (ii) designing high scalable parallel algorithms and (iii) supporting \fault-tolerant" distributed computing. Several open problems in the study of quasigroups have been solved using PSATO.