Abstract. Today’s parallel computers with SMP nodes provide both multithreading and message passing as their modes of parallel execution. As a consequence, performance analysis and optimization becomes more difficult and creates a need for advanced performance tools that are custom made for this class of computing environments. Current state-of-the-art tools provide valuable assistance in analyzing the performance of MPI and OpenMP programs by visualizing the runtime behavior and calculating statistics over the performance data. However, the developer of parallel programs is still required to filter out relevant parts from a huge amount of low-level information shown in numerous displays and map that ion onto program abstractions without tool support. The KOJAK project (Kit for Objective Judgement and Knowledge-based Detection of Performance Bottlenecks) is aiming at the development of a generic automatic performance analysis environment for parallel programs. Performance problems ...