Construction and Deconstruction of Hierarchical Event Streams with Multiple Hierarchical Layers

Compositional scheduling analysis couples local scheduling analysis via event streams. While local analysis has successfully been extended to include hierarchical scheduling strategies, event streams are still flat. In this paper, we formally define hierarchical event streams, which cannot only be constructed from flat event streams, but also from hierarchical streams allowing event streams with multiple hierarchical layers. We define an hierarchical event model and the operations to construct and deconstruct hierarchical events streams. Finally, we demonstrate how the model can be integrated in an existing analysis approach for distributed systems, enabling superior analysis results.