A portable programming interface for performance evaluation on modern processors

The purpose of the PAPI project is to specify a standard application progra mming interface (API) for accessing hardware performance counters available on most modern microprocessors. These counters exist as a small set of reg isters that count events, which are occurrences of specific signals and sta tes related to the processor's function. Monitoring these events facilitate s correlation between the structure of source/object code and the efficienc y of the mapping of that code to the underlying architecture. This correlat ion has a variety of uses in performance analysis, including hand tuning, c ompiler optimization, debugging, benchmarking, monitoring, and performance modeling. In addition, it is hoped that this information will prove useful in the development of new compilation technology as well as in steering arc hitectural development toward alleviating commonly occurring bottlenecks in high performance computing.