1Generalized Elastic Scheduling for Real-Time Tasks

Abstract — The elastic task model is a powerful model for adapting periodic real-time systems in the presence of uncer-tainty. This paper generalizes the existing elastic scheduling approach in several directions. It reveals that the original task compression algorithm in fact solves a quadratic programming problem that seeks to minimize the sum of the squared deviation of a task’s utilization from initial desired utilization. This finding indicates that the task compression algorithm may be applied to efficiently solve other similar types of problems that often arise in real-time applications. In particular, an iterative approach is proposed to solve the task compression problem for real-time tasks with deadlines less than respective periods. Furthermore, the framework is generalized to adjust task deadlines instead of task periods. Index Terms — Real-time and embedded systems, Sequencing and scheduling, Performance of system