To make strategic investment decisions on storage, it’s important to be able to gauge how long a drive will last with a given workload. Fortunately, SSD endurance can be accurately predicted using Self-Monitoring, Analysis and Reporting Technology (SMART), which allows a drive to report back to the system it’s connected to, sending data on a number of attributes that indicate drive health and reliability.
Drive lifespans for SSDs can be roughly estimated based on the total number of bytes written to the drive. However, since data is written to SSDs in blocks, data that is less than a block causes wear amplification, since a whole block must be written even if only a few bits have been changed. The data needed to predict SSD endurance includes the drive size, the number of program/erase cycles, the write amplification factor and the wear leveling factor, which pertains to how data is distributed over the drive to make sure that some cells don’t wear out before others.
There are a number of utilities, such as Samsung Magician DC, which can be used to record the necessary data and then estimate how long the drive will operate at similar loads. For more information, read the white paper below.