A runtime synthesis time reduction method for self-adaptive systems using reuse controller synthesis.

Abstract

A self adaptive system that can operate in a changing environment to satisfy its functional requirements is realized by reasoning on runtime models. Existing studies proposed such runtime model techniques, for example, reflecting changes in the environment in an environment model and synthesizing new behavior based on the updated environment and requirement models by using discrete controller synthesis. However, discrete controller synthesis requires huge computation time for large scale environments and complex requirements, and this is an issue for applying it to the resynthesis of controllers at runtime. In this paper, we propose a reuse controller synthesis, which reuses a part of the result of the previous controller synthesis during resynthesis. We evaluate the usefulness of the reuse controller synthesis through three concrete examples. Results show that, compared to the conventional controller synthesis, it can resynthesize controllers in about 0.1 percent of the execution time at most.