SMART (often represented as S.M.A.R.T.) stands for Self-Monitoring, Analysis and Reporting Technology. Its purpose is to report specific data from rotating Hard Disk Drives (HDD) and Solid State Drives (SSD) related to the reliability of the device. This data can then be analyzed to anticipate potential failures in the near future and predict the remaining life of a product.
The SMART feature began in the world of HDDs. With mechanical issues accounting for >60% of HDD failures, the failure itself can often be predicted by analyzing increasing heat output, noise level, error correction required and failed or bad sectors.
Once a specified threshold is reached in one of these categories, a conservative approach would be to replace the HDD at the next regularly scheduled maintenance to avoid a potential unscheduled catastrophic failure.
Fast forward to SSDs and SMART reporting is very useful if the proper data points are analyzed. Since the data reported for HDDs is rightly focused on predicting mechanical failures, it is not as relevant for SSD. For this reason, there is not a single SMART reporting format and different devices (HDD/SSD) and manufacturers report different SMART data.
SSDs tend to focus their reported data on the more critical flash memory items such as wear leveling, erase block counts, error checking and correction errors and spare block count. Cactus and most SSD vendors focused on the OEM/Industrial market will provide this SMART data reporting structure and in many cases a utility to read this data from the device.
For mission critical applications, it is especially important to design-in the correct type of flash storage product from the beginning - based on the system’s usage model. In addition, many OEMs design their systems to read SMART data periodically during operation and flag when a predetermined threshold is met. Once flagged, immediate action can be taken or the situation monitored more carefully.
SMART command and related data structure information is available in select Cactus product manuals. In addition, there are several white papers that explain many of the detailed flash memory attributes to be aware of on the front end of Industrial or Mission Critical designs.
If you have any questions, feel free to talk to a Cactus Expert for assistance.
NOTE: SSDs in the context of this post refer to many varieties of solid state devices including Compact Flash, PC Card, 2.5” SSD, and several others.