An Overview of Approaches Towards the Timing Analysability of Parallel Architecture

In order to meet performance/low energy/integration requirements, parallel architectures (multithreaded cores and multi-cores) are more and more considered in the design of embedded systems running critical software. The objective is to run several applications concurrently. When applications have strict real-time constraints, two questions arise: a) how can the worst-case execution time (WCET) of each application be computed while concurrent applications might interfere? b)~how can the tasks be scheduled so that they are guarantee to meet their deadlines? The second question has received much attention for several years~\cite{CFHS04,DaBu11}. Proposed schemes generally assume that the first question has been solved, and in addition that they do not impact the WCETs. In effect, the first question is far from been answered even if several approaches have been proposed in the literature. In this paper, we present an overview of these approaches from the point of view of static WCET analysis techniques.

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