Decomposing SAT Problems into Connected Components

Many SAT instances can be decomposed into connected components either initially after preprocessing or during the solution phase when new unit conflict clauses are learned. This observation allows components to be solved individually. We present a technique to handle components within a GRASP like SAT solver without requiring much change to the solver. Results obtained when applying our implementation in the SAT solver COMPSAT to a number of realistic examples show that components really do occur in practice. We also provide some evidence that component structure can be used to improve performance.