Google Data Center Technician Practice Exam

The signal that indicates wear-out in an SSD is the Media Wearout Indicator value, which reports the remaining write endurance of the flash memory. As you write data, the flash cells wear down, and the MWI changes to reflect how much life is left. When this indicator reaches a threshold that signals end-of-life, it’s a clear warning that the drive is nearing wear-out. This makes MWI the most direct and reliable sign of wear-out because it specifically tracks endurance, not just how long the drive has been powered, how many blocks have already failed, or the current temperature.

Power-on hours only show how long the drive has been in use, not how much usable life remains. Reallocated Sector Count shows blocks that have already failed and were remapped, which indicates degradation but is not a direct measure of remaining endurance. Temperature rises point to thermal conditions that can affect reliability, but they don’t quantify wear independently.