Timing analysis of an avionics case study on complex hardware/software platforms

Probabilistic Timing Analysis (PTA) in general and its measurement-based variant called MBPTA in particular have been shown to facilitate the estimation of the worst-case execution time (WCET). MBPTA relies on specific hardware and software support to randomise and/or upper bound a number of sources of execution time variation to drastically reduce the need for user-provided information, thus replacing uncertainty by probabilities. MBPTA has been proven effective for specific single-core processor designs. However, particular hardware features and multicores in general challenge MBPTA application in industrial-quality developments. While solutions to those challenges have been proven on benchmarks, they have not been proven yet on real-world applications, whose timing analysis is far more challenging than that of simple benchmarks. This paper discusses the application of MBPTA to a real avionics system in the context of (1) software-only single-core solutions and (2) hardware-only multicore solutions with an ARINC 653 operating system.