Worst-case communication delay analysis for many-cores using a Limited Migrative Model

A steady increase in the number of cores within many-core platforms causes increasing contentions for the interconnect medium and leads to non-negligible latencies of intercore communication. In order to study the worst-case execution times of applications, it is no longer sufficient to only take into account schedulability requirements, but the communication delays also have to be considered. In this paper we focus on the worst-case communication delays of applications, assuming a Limited Migrative Model (LMM). LMM is an approach based on the multi-kernel paradigm - a promising step towards scalable and predictable many-cores. The contribution of this paper is threefold. First, we extend LMM by allowing inter-application communication, and adapt the existing worst-case communication delay analysis, to make it applicable to the enhanced model. Then, we propose a novel analysis. Finally, we compare these two methods. The experiments show that the new approach renders tighter upper-bound estimates in more than 90% of the cases, while demonstrating a comparable runtime performance.

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