The name of the Surface Scan test is not particularly apt for SSD drives, but the test is still valid. It is simply reading blocks, one after another, to make sure that they can be read. We have had customers run the Surface Scan to check SD cards used in cameras, and a few have been found to be defective.
Save the results of the Surface Scan, so it a later lest finds errors (unremapped bad blocks), you will have a good basis for a warranty claim.
It seems as if running a surface scan on an SSD when it's brand new and then again periodically but infrequently is a good idea.[/quote]
S.M.A.R.T. was intended to be a reliable guide to drive health, but in practice it turned out to her unreliable because drive manufacturers set the tolerance levels so high S.M.A.R.T. became relatively meaningless. That was particularly true because all of the utilities, except TechTool Pro, reported only a single pass/fail value and provided no opportunity for users to observe trends. The ability to
see all of the S.M.A.R.T. values and their acceptable range as provided in TechTool Pro provides a good tool for analyzing
hard drive health.
Then came SSD with a different set of S.M.A.R.T. values that could be used to infer drive health if drive health was indicated by the same factors that had been used for hard drives. But that has evolved in later SSDs into NVMe data which includes among many other things information that can be used to analyze drive health such as:
- unsafe shutdowns
- % available spares
- % available spare threshold
- % percentage used
- % percentage remaining
- data units read
- data units written
- available space below threshold (Y/N)
- over temperature threshold (Y/N)
- NVM subsystem reliability degraded (Y/N)
- Media in read only mode (Y/N)
- volitile memory backup device failure (Y/N)
Once again Macromedia has the only products that give the full report, TechTool Pro and Drive Scope. Drive Scope is a tool that is specifically for reporting this data from SSD drives and that is all it can do other than report SMART logs.
IMHO the full S.M.A.R.T. data report provides essentially the same information as a surface scan and a LOT more.
Disk Utility still reports only the SMART verified/fail. ðŸ˜
FULL DISCLOSURE: I receive no remuneration whatsoever from Micromat other than being a satisfied customer.
CONFESSION: For many years I have touted the value of surface scans based on the results of a study conducted by google LABS. It is only recently I have become fully convinced of the value of SMART
when all of the SMART values are available for analysis.
