Optimizing energy efficiency of 3-D multicore systems with stacked DRAM under power and thermal constraints

3D multicore systems with stacked DRAM have the potential to boost system performance significantly; however, this performance increase may cause 3D systems to exceed the power budget or create thermal hot spots. This paper introduces a framework to model on-chip DRAM accesses and analyzes performance, power, and temperature tradeoffs of 3D systems. We propose a runtime optimization policy to maximize performance while maintaining power and thermal constraints. Our policy dynamically monitors workload behavior and selects among low-power and turbo operating modes accordingly. Experiments with multithreaded workloads demonstrate up to 49% energy efficiency improvements compared to existing thermal management policies.