Runtime Optimization of Application Level Communication Patterns

This paper introduces the Abstract Data and Communication Library (ADCL). ADCL is an application level communication library aiming at providing the highest possible performance for application level communication operations on a given execution environment. The library provides for each communication pattern a large number of implementations and incorporates a runtime selection logic in order to choose the implementation leading to the highest performance of the application on the current platform. Two different runtime selection algorithms are currently available within ADCL: the library can either apply a brute force search strategy which tests all available implementations of a given communication pattern; alternatively, a heuristic relying on attributes characterizing an implementation has been developed in order to speed up the runtime decision procedure. The paper also evaluates the performance of a finite difference code using ADCL on an AMD Opteron cluster using InfiniBand and Gigabit Ethernet interconnects.