Processor affinity and MPI performance on SMP-CMP clusters

Clusters of Symmetric MultiProcessing (SMP) nodes with multi-core Chip-Multiprocessors (CMP), also known as SMP-CMP clusters, are becoming ubiquitous today. For Message Passing interface (MPI) programs, such clusters have a multilayer hierarchical communication structure: the performance of intra-node communication is usually higher than that of internode communication; and the performance of intra-node communication is not uniform with communications between cores within a chip offering higher performance than communications between cores in different chips. As a result, the mapping from Message Passing Interface (MPI) processes to cores within each compute node, that is, processor affinity, may significantly affect the performance of intra-node communication, which in turn may impact the overall performance of MPI applications. In this work, we study the impacts of processor affinity on MPI performance in SMP-CMP clusters through extensive benchmarking and identify the conditions whe...

• Type: Journal
• Year: 2010
• Where: IPPS
• Authors: Chi Zhang, Xin Yuan, Ashok Srinivasan
• Keywords: Communication, Distributed And Parallel Computing, IPPS 2010, Performance, SMP-CMP Clusters