Parametric Performance Contracts for Software Components with Concurrent Behaviour

Performance prediction methods for component-based software systems aim at supporting design decisions of software architects during early development stages. With the increased availability of multicore processors, possible performance gains by distributing threads and processes across multiple cores should be predictable by these methods. Many existing prediction approaches model concurrent behaviour insufficiently and yield inaccurate results due to hard underlying assumptions. In this paper, we present a formal performance prediction approach for component-based systems, which is parameterisable for the number of CPUs or CPU cores. It is able to predict the response time of component services for generally distributed execution times. An initial, simple case study shows that this approach can accurately predict response times of multithreaded software components in specific cases. However, it is limited if threads change the CPU during their execution, if the effect of processor cache thrashing is present, and if the memory bus is heavily used.