An Efficient Control-Driven Period Optimization Algorithm for Distributed Real-Time Systems

The sampling periods of real-time embedded control functions have a significant impact on control performance and system schedulability. Exploring period assignment for optimizing control performance while meeting schedulability constraints is very challenging, in particular for distributed systems where control loops share a network of computation and communication resources. In this work, we propose an efficient approach that approximates the performance of each control loop in the system with a piecewise linear function of its sampling period and end-to-end delay, and then optimizes the periods of tasks and messages by exploring the linear partitions of the approximated functions and solving a series of geometric programming (GP) formulations. Experiments on sample control models, an automotive industrial case study and a set of synthetic examples demonstrate the effectiveness and efficiency of our approach.