CAREER: Energy-Exposed Instruction Sets

Massachusetts Institute Of Technology, Cambridge MA

Investigators

Abstract

Energy consumption is a key constraint in the design of modern microprocessors, limiting battery life in portable devices and achievable performance in high-performance systems. Modern instruction set architectures such as RISC or VLIW are based on extensive research into how instruction set design affects performance, and provide a purely performance-oriented hardware-software interface. Implementations of these ISAs perform many energy-consuming microarchitectural operations during execution of each user-level instruction and these dominate total power dissipation. Because modern architectures pipeline and parallelize this microarchitectural work, it has little effect on the latency and throughput of user instructions, thus there is no incentive to expose the micro-operations in a purely performance-oriented hardware-software interface: energy consumption is hidden from software. The project will develop new energy-exposed microprocessor architectures that give software much greater control over the microarchitectural components used to execute each operation. The research will develop new integrated hardware and software energy-saving techniques by simultaneously considering all levels of processor design, including VLSI circuits, microarchitectures, instruction sets, compilers, and operating systems. The project will also be used to bring energy-efficiency into the curriculum of existing undergraduate and graduate computer architecture courses.