The Sync Model: A Parallel Execution Method for Logic Programming

Abstract

The Sync Model, a parallel execution method for logic programming, is proposed. The Sync Model is a multiple-solution data-driven model that realizes AND parallelism and OR-parallelism in a logic program assuming a message-passing multiprocessor system. AND parallelism is implemented by constructing a dynamic data flow graph of the literals in the clause body with an ordering algorithm. OR parallelism is achieved by adding special Synchronization signals to the stream partial solutions and synchronizing the multiple streams with a merge algorithr The ordering algorithm and the merge algorithm are described. The merge algrithm is proved to be correct and therefore, the Sync Model is proved complete, i.e the execution of a logic program under the Sync Model generates all the solution