Architectural Influence on the Timing Predictability

Hard real-time systems need safe methods to determine the upper bound on their execution times. These bounds are obtained by a multi-phase approach, whose core is the static analysis of the hardware platform's behavior for the program under analysis. The problem of determining upper bounds on execution times for single tasks and for quite complex processor architectures has been solved. Several commercial WCET tools are available and have experienced very positive feedback from extensive industrial use. This feedback concerned speed, precision of the results, and usability. The aiT timing-analysis tool has been used in the certification of several time-critical applications in the Airbus A380 and thereby has been accepted as a validated tool for these applications by the European Airworthiness Authorities.