Real-Time Priority Assignment for AUTOSAR-based Systems with Time-Driven Synchronization

Abstract

AUTOSAR is a standard framework that aims to address many software challenges such as composability, reusability and interoperability during automotive system development. To overcome these challenges, its specifications provide a basic infrastructure for software architecture, application interfaces, and development methodology, but still leave many detailed design decisions to developers such as runnable-to-task mapping and task priority assignment. Although these design decisions have a significant impact on the overall system performance, they have not been sufficiently addressed in the AUTOSAR standard framework. In this paper, we attempt to solve the priority assignment problem for AUTOSAR tasks and in-vehicle network messages. To do so, we first describe a real-time task chain model for AUTOSAR that is amenable to schedulability analysis, and then present a genetic priority assignment algorithm that can find near optimal solutions in a moderate amount of time. Our experiments show that the proposed algorithm outperforms existing methods, producing 6% better schedulable solutions than HOPA [4] and running 18 times faster than PGA [5].