Using fine grain multithreading for energy efficient computing

Alex Gontmakher, Avi Mendelson, Assaf Schuster

Abstract: We investigate extremely fine-grain multithreading as a means for improving energy efficiency of single-task program execution.Our work is based on low-overhead threads executing an explicitly parallel program in a register-sharing context. The thread-based parallelism takes the place of instruction-level parallelism, allowing us to use simple and more energy-efficient in-order pipelines while retaining performance that is characteristic of classical out-of-order processors. Our evaluation shows that in energy terms, the parallelized code running over in-order pipelines can outperform both plain in-order and out-of-order processors.