Seven Challenges in Parallel SAT Solving

A set of challenges to researchers is presented that, we believe, must be met to ensure the practical applicability of parallel SAT solvers in the future. All these challenges are described informally but put into perspective with related research results, and a (subjective) grading of difficulty for each of them is provided. Parallelism is the wave of the future … and always will be. It conveys a general sentiment that the coming of parallel architectures would forever be delayed. This was indeed true at a time when clock-speed growth seemed always possible, allowing sequential code seamlessly to become faster.