A tool for on-line visualization and interactive steering of parallel HPC applications

Tools for parallel systems today range from specification over debugging to performance analysis and more. Typically, they help the programmers of parallel algorithms from the early development stages to a certain level of program optimization. However in HPC (High Performance Computing) today the end-user of massively parallel CFD (Computational Fluid Dynamics)-programs has little or no support in his work. The scientific engineer who often runs his application on a parallel computer somewhere in the WAN (Wide Area Network) and visualizes the enormous amounts of simulation data on a graphical workstation in his LAN (Local Area Network) has needs which are by far not covered by state of the art visualization systems. The tool proposed here follows a strategy which differs completely from existing, batch-oriented and strictly sequential methods of the working process in the application cycle of parallel HPC applications. It allows both on-line visualization and interactive program steering of massively parallel CFD-applications. The parameters of the mathematical model and the numerical methods build objects of a database which can be accessed by an object-oriented graphical user interface via visualization and modification operators. Experiences with this new tool concept VIPER (VIsualization of Parallel numerical simulation algorithms for Extended Research) applied on a real-world and industrial scientific application will be shown.