Understanding Cache Compression

Abstract

Hardware cache compression derives from software-compression research; yet, its implementation is not a straightforward translation, since it must abide by multiple restrictions to comply with area, power, and latency constraints. This study sheds light on the challenges of adopting compression in cache design—from the shrinking of the data until its physical placement. The goal of this article is not to summarize proposals but to put in evidence the solutions they employ to handle those challenges. An in-depth description of the main characteristics of multiple methods is provided, as well as criteria that can be used as a basis for the assessment of such schemes. It is expected that this article will ease the understanding of decisions to be taken for the design of compressed systems and provide directions for future work.