A Technique to Calculate Cache Related Preemption Delay Using Constraints on Non-nested Preemptions

Caches incur an indirect cost to the response times of tasks due to preemptions in a task system. Hence the computation of Cache Related Preemption Delay (CRPD) is an important problem to assess the schedulability of a task system. In this paper, we have introduced the concept of inhibiting and non-nested preemptions. We have proposed a novel method to calculate tight upper and lower bounds on the number of preemptions of every task in the task-system across all phases. The problem of calculation of CRPD is modelled as a constraint satisfaction problem that can be solved by using Integer Linear Programming (ILP). The CRPD values are integrated in the worst case response time analysis.