Scalable and optimal planning based on Pregel

Abstract

Summary Automated planning generates plans for specific tasks. Optimal planning aims at generating optimal plans under global constraints. As a result, the divide‐and‐conquer method is not applicable for optimal planning. Therefore, engineering applications of optimal planning face the scalability issue. Fortunately, cloud computing tools are on the shelf. For example, the Apache Spark is an engine for big data processing. It supports the Pregel for scalable computing. Therefore, we proposed an optimal Planning method based on the Pregel, called the PbP. Unlike classical planning, the PbP method uses the Pregel as the computation model, instead of the traditional state‐space searching. The core idea is to transform planning problems into graph processing problems. Specifically, actions are mapped into vertices, partial orders between actions are mapped into edges between vertices, and states are mapped into messages. Furthermore, the planning is viewed as message propagating in the graph, and plan traces are stored as attributes of vertices. Experimental results showed the feasibility of the proposed method PbP. Moreover, compared with state‐of‐the‐art optimal planners, our approach is more scalable and faster.