Assessing contention effects of all‐to‐all communications on clusters and grids
International Journal of Pervasive Computing and Communications
One of the most important collective communication patterns used in scientific applications is the complete exchange, also called All-to-All. Although efficient algorithms have been studied for specific networks, general solutions like those available in wellknown MPI distributions (e.g. the MPI_Alltoall operation) are strongly influenced by the congestion of network resources. In this paper we present an integrated approach to model the performance of the Allto-All collective operation, which
... e operation, which consists in identifying a contention signature that characterizes a given network environment, using it to augment a contentionfree communication model. This approach, assessed by experimental results, allows an accurate prediction of the performance of the All-to-All operation over different network architectures with a small overhead. We also discuss the problem of network contention in a grid environment, studying some strategies to minimize the impact of contention on the performance of an Allto-All operation.