Resource Reservation for Mixed Criticality Systems

Abstract

Abstract. This paper presents a reservation-based approach to schedule mixed criticality systems in a way that guarantees the schedulability of high-criticality tasks independently of the behaviour of low-criticality tasks. Two key ideas are presented: first, to reduce the system uncertainty and advance the time at which a high-criticality task reveals its actual execution time, the initial portion of its code is handled by a dedicated server with a bandwidth reserved for the worst-case, but with a shorter deadline; second, toavoidthepessimism relatedtooff-linebudget allocation, an efficient reclaiming mechanism, namely the GRUB algorithm [6], is used to exploit the budget left by high-criticality tasks in favor of those low-criticality tasks that can still complete within their deadline.