John McCalpin is a Research Scientist in the High Performance Computing Group at TACC. Before joining TACC, he was a senior individual contributor in performance analysis and system architecture in the computer industry. His industrial experience includes performance analysis and server system architecture at both SGI and IBM, and he served as technology lead for the Torrenza program at AMD (supporting third-party accelerated computing technologies). Prior to his industrial career, John spent six years on the faculty of the University of Delaware, engaged in research and teaching on numerical simulation of the large-scale circulation of the oceans. Best known for the STREAM Benchmark, McCalpin's research interests focus on understanding the complex interactions among the many components of modern memory hierarchies, characterizing important applications in HPC, and developing a system architecture that includes communication and synchronization as first class features.