Performance models of flash-based solid-state drives for real workloads

Abstract

There is a wide gap between the potential performance of NAND flash-based solid state drives (SSDs) and their performance in many real-world applications; understanding this gap requires knowledge of their behavior and internal algorithms for various workloads. We develop analytic models for two commonly-used Flash Translation Layer (FTL) algorithms, as used in SSDs, as well as a methodology for applying these models to real-world workloads. We demonstrate the accuracy of these models via simulation, extend this approach to incorporate measurement-based approximations when detailed parameters are unknown, and validate this methodology against real devices.