Identifying optimal trade-offs between CPU time usage and temporal constraints using search

Abstract

Integration of software from different sources is a critical activity in many embedded systems across most industry sectors. Software integrators are responsible for producing reliable systems that fulfil various functional and performance requirements. In many situations, these requirements inversely impact one another. In particular, embedded system integrators often need to make compromises regarding some of the functional system properties to optimize the use of various resources, such as CPU time. In this paper, motivated by challenges faced by industry, we introduce a multi-objective decision support approach to help balance the minimization of CPU time usage and the satisfaction of temporal constraints in automotive systems. We develop a multi-objective, search-based optimization algorithm, specifically designed to work for large search spaces, to identify optimal trade-off solutions fulfilling these two objectives. We evaluated our algorithm by applying it to a large automotive system. Our results show that our algorithm can find solutions that are very close to the estimated ideal optimal values, and further, it finds significantly better solutions than a random strategy while being faster. Finally, our approach efficiently identifies a large number of diverse solutions, helping domain experts and other stakeholders negotiate the solutions to reach an agreement.