A Study of SSD Reliability in Large Scale Enterprise Storage Deployments

This paper presents the first large-scale field study of NAND-based SSDs in enterprise storage systems (in contrast to drives in distributed data center storage systems). The study is based on a very comprehensive set of field data, covering 1.4 million SSDs of a major storage vendor (NetApp). The drives comprise three different manufacturers, 18 different models, 12 different capacities, and all major flash technologies (SLC, cMLC, eMLC, 3D-TLC). The data allows us to study a large number of factors that were not studied in previous works, including the effect of firmware versions, the reliability of TLC NAND, and correlations between drives within a RAID system. This paper presents our analysis, along with a number of practical implications derived from it.