SSD Endurance Standardized – MTBF Has to Go
JEDEC has published new standards for measuring lifetime and reliability in SSDs. The new standards, JESD218 (Solid-State Drive (SSD) Requirements and Endurance Test Method) and JESD219 (Solid-State Drive Endurance Workloads), are intended to make it easier for businesses to choose the best products for their needs.
The idea is to even out the playing field for solid state drives by using measurements that are more suitable for SSDs than the existing MTBF (Mean Time Before Failure) standard, which has previously been used as a statistical measure of life span for hard drives. These are however not equally well suited for flash drives, which are based on entirely different technology.
Since SSDs are exposed to various levels of load depending on different types of usage, the new standards are defined according to two application classes: Client and Enterprise.
JESD218 creates a measurement of endurance called TWB, which represents the number of terabytes of data written to the tested drives. This can be used to compare different flash drives within the same application class.
JESD219 create metrics on workload management, where the workload is standardized.