Energy efficient D-TLB and data cache using semantic-aware multilateral partitioning

The memory subsystem, including address translations and cache accesses, consumes a major portion of the overall energy on a processor. In this paper, we address the memory energy issues by using a streamlined architectural partitioning technique that effectively reduces energy consumption in the memory subsystem without compromising performance. It is achieved by decoupling the d-TLB lookups and the data cache accesses, based on the semantic regions defined by programming languages and software convention, into discrete reference substreams - stack, global static, and heap. Their unique access behaviors and locality characteristics are analyzed and exploited for power reduction. Our results show that an average of 35% energy can be reduced in the d-TLB and the data cache. Furthermore, an average of 46% energy can be saved by selectively multi-porting the semantic-aware d-TLBs and data caches against their monolithic counterparts.