Application Sensitivity to Link and Injection Bandwidth on a Cray XT4 System
Source: Sandia National Laboratories
This paper describes the efforts to characterize application sensitivity to link and injection bandwidth on a Cray XT4 system. Link bandwidth is controlled by modifying the number of rails activated per network link. Injection bandwidth is controlled by modifying the speed of the HyperTransport connection between the Opteron and the SeaStar. A suite of micro-benchmarks and applications is evaluated at several different operating points. The experimental techniques developed by this paper are expected to be useful for future architecture research.