Comparing Direct-to-Cache Transfer Policies to TCP/IP and M-VIA During Receive Operations in MPI Environments

摘要

The main contributors to message delivery latency in message passing environments are the copying operations needed to transfer and bind a received message to the consuming process/thread. To reduce this copying overhead, we introduce architectural extensions comprising a specialized network cache and instructions. In this work, we study the possible overhead and cache pollution introduced through the operating system and the communications stack as exemplified by Linux, TCP/IP and M-VIA. We introduce this overhead in our simulation environment and study its effects on our proposed extensions. Ultimately, we have been able to compare the performance achieved by an application running on a system incorporating our extensions with the performance of the same application running on a standard system. The results show that our proposed approach can improve the performance of MPI applications by 10% to 20%.