SSD architecture and PCI express interface

Abstract

Flash-memory-based solid-state drives (SSDs) provide faster random access and data transfer rates than electromechanical drives and today can often serve as rotating-disk replacements, but the host interface to SSDs remains a performance bottleneck. PCI Express (PCIe)-based SSDs together with the standard called NVMe (Non-Volatile Memory express) solves this interface bottleneck. This chapter walks the reader through the SSD block diagram, from the NAND memory to the Flash controller (including wear leveling, bad block management, and garbage collection). PCIe basics and different PCIe SSD architectures are reviewed. Finally, an overview on the standardization effort around PCI Express is presented.