Dynamic Performance Callstack Sampling: Merging TAU and DAQV

Observing the performance of an application at runtime requires economy in what performance data is measured and accessed, and flexibility in changing the focus of performance interest. This paper describes the performance callstack as an efficient performance view of a running program which can be retrieved and controlled by external analysis tools. The performance measurement support is provided by the TAU profiling library whereas tool-program interaction support is available through the DAQV framework. How these systems are merged to provide dynamic performance callstack sampling is discussed.