Abstracting functionality for modular performance analysis of hard real-time systems

System level performance analysis techniques play an important role in the design process of complex embedded systems. They allow analyzing essential characteristics of a system design in an early design stage and supporting therewith the choice of important design decisions. While analytical methods for system level performance analysis lead to hard bounded analysis results, the obtained results are often overly pessimistic due to a lack of details such analytical methods can incorporate in their system analysis. To overcome this problem, we present new abstract models for event streams and system components of embedded systems, and show how these models can be combined to modules for modular performance analysis. With the presented models, we can capture complex functional properties of systems, as for example caches, variable resource demand of events in an event stream, or arbitrary up- and down-sampling of event streams in a system component. The applicability of our models and their advantages over traditional models for performance analysis are shown in a case study of a system component with LRU (least recently used) cache.