A Study of Soft Error Consequences in Hard Disk Drives

Hard disk drives have multiple layers of fault tolerance mechanisms that protect against data loss. However, a few failures occasionally breach the entire set of mechanisms. To prevent such scenarios, the authors rely on failure prediction mechanisms to raise alarms with sufficient warning to allow the at-risk data to be copied to a safe location. A common failure prediction technique monitors the occurrence of soft errors and triggers an alarm when the soft error rate exceeds a specified threshold. This study uses data collected from over 50,000 customer deployed disk drives to evaluate the performance of a failure prediction algorithm that relies solely on soft errors to predict failures manifested as hard errors.