Work-in-Progress Paper: An Analysis of the Impact of Dependencies on Probabilistic Timing Analysis and Task Scheduling

Abstract

Recently there has been a renewed interest for probabilistic timing analysis (PTA) and probabilistic task scheduling (PTS). Despite the number of works in both fields, the link between them is weak: works on the latter build upon a series of assumptions on the probabilistic behavior of each task – or instances (jobs) of it – that have not been shown how to be fulfilled by PTA. This paper makes a first step towards covering this gap with emphasis on providing the right meaning of pWCET estimate as understood by both PTA and PTS. We show that the main issue related to ensuring that PTS assumptions on pWCET estimates are captured by PTA relates to the dependencies among tasks, and even jobs of a given task. Both change the scope of applicability of pWCET estimates provided by PTA and hence, their use by PTS.