Assessing Processor Sustainability Using the First-Order FOCAL Carbon Model

To overcome the inherent data uncertainty regarding the sustainability of computing devices in general and processors in particular, this article proposes the parameterized First-Order analytical CArbon modeL (FOCAL) to assess processor sustainability from first principles. FOCAL’s normalized carbon footprint metric guides computer architects to holistically optimize chip area, energy, and power consumption to reduce a processor’s environmental footprint. We use FOCAL to analyze and categorize a broad set of archetypal processor mechanisms into strongly, weakly, or less sustainable design choices, providing insight and intuition into how to reduce a processor’s environmental footprint with implications to both hardware and software. A case study illustrates a pathway for designing strongly sustainable multicore processors delivering high performance while at the same time reducing their environmental footprint.