Dynamic cache pooling for improving energy efficiency in 3D stacked multicore processors

Resource pooling, where multiple architectural components are shared among multiple cores, is a promising technique for improving the system energy efficiency and reducing the total chip area. 3D stacked multicore processors enable efficient pooling of cache resources owing to the short interconnect latency between vertically stacked layers. This paper introduces a 3D multicore architecture that provides poolable cache resources. We propose a runtime policy that improves energy efficiency in 3D stacked processors by providing flexible heterogeneity of the cache resources. Our policy dynamically allocates jobs to cores on the 3D stacked system in a way that pairs applications with contrasting cache use, while also partitioning the cache resources based on the cache hungriness of the applications. Experimental results demonstrate that the proposed policy improves system energy-delay product (EDP) and energy-delay-area product (EDAP) by up to 39.2% and 57.2%, respectively, compared to 3D processors with static cache sizes.