Storage Class Memory: Principles, Problems, and Possibilities

TL;DR

This paper reviews Storage Class Memory technologies like PCM, STT-RAM, and ReRAM, discussing their operation, challenges such as endurance and performance, and exploring future prospects including multi-level cells and accelerator applications.

Contribution

It provides a comprehensive overview of SCM principles, analyzes current problems, and discusses future possibilities and applications in accelerators.

Findings

SCM exhibits non-volatility with low latency and byte-addressability.

Endurance and performance are key challenges for SCM technologies.

Future directions include multi-level cells and accelerator integration.

Abstract

Storage Class Memory (SCM) is a class of memory technology which has recently become viable for use. Their namearises from the fact that they exhibit non-volatility of data, similar to secondary storage while also having latencies comparable toprimary memory and byte-addressibility. In this area, Phase Change Memory (PCM), Spin-Transfer-Torque Random Access Memory(STT-RAM), and Resistive RAM (ReRAM) have emerged as the major contenders for commercial and industrial use. In this paper, wedescribe how these memory types function, while highlighting the problems of endurance and performance that these memory typesface. We also discuss the future possibilities of Multi-Level Cells (MLCs), as well as how SCM can be used to construct accelerators.