T. Scogland, P. Balaji, W. Feng, and G. Narayanaswamy, "Asymmetric Interactions in Symmettric Multi-core Systems: Analysis, Enhancements, and Evaluation," Preprint ANl/MCS-P1603-1108, November 2008. [pdf]
Multi-core architectures have spurred the recent rapid growth in high-end computing systems. While the vast majority of such multi-core processors contain symmetric hardware components, their interaction with systems software, in particular the communication stack, results in a remarkable amount of asymmetry in the effective capability of the different cores. In this paper, we analyze such interactions and propose a novel management library called SyMMer (Systems Mapping Manager) that monitors these interactions and dynamically manages the mapping of processes on processor cores to transparently improve application performance. Together with a detailed description of the SyMMer library, we also present performance evaluation comparing SyMMer to a vanilla communication
library using various micro-benchmarks as well as popular applications and scientific libraries. Experimental results demonstrate more than a two-fold improvement in communication time and 10-15% improvement in overall application performance.