Influence of Network Bandwidth on Parallel Computing Performance with Intra-node and Inter-node Communication

As technologies such as symmetrical multiprocessing (SMP) and multicore processor (MCP) advanced, more and more computational cores are contained in one node. Therefore, parallel applications running on a cluster can exchange data among processes through either intra-node or inter-node communication. This gives rise to the question of how much network bandwidth impact on parallel computing performance when intra-node and inter-node communications exist in a certain proportion. In this paper, we try to analyze and estimate this impact via using communication mechanism of message passing interface (MPI) and multi-core technology. The results show that the proportion of intra-node communication to inter-node communication has a significant effect on performance when the network bandwidth is between 50~400Mib/s, especially about 200Mib/s.