A hard real-time scheduling algorithm based on elastic model

Hard real-time systems are time critical systems and widely used in aerospace and other fields. One of the key issues for hard real-time systems is how to increase the CPU utilization while making sure that all tasks would be completed before deadlines. This paper combines EDF and elastic theory and proposes a new algorithm ELTBF to implement the scheduling of hard real-time system with hard periodic tasks and hard aperiodic tasks. Compared with EDF, ELTBF has higher CPU utilization and lower preempt times, and makes sure the number of deadlines missed is zero.