2010 MacBook Air diagnostics and potential revival (HWTech)

Continued....

Over the years I have learned how to pick & choose which attributes to focus on and whether I should consider the "Raw Value" in my evaluation. The "Value"/"Worst"/"Threshold" will always be the ultimate judge of the drive's actual health. If the "Worst" reaches or exceeds the "Threshold" to indicate a worn out or failing drive respectively. I have never found anything online to actually fully explain all of these things. I have only seen bits & pieces of clues here & there which I've pieced together and used them along with my own personal observations, experience.....putting all of these tidbits together so that I can best decide what to do with any drive I encounter while supporting my organization's computers for decades.

I learned all of this long before I ever saw blogs from BackBlaze in 2013 about their own research into how best to utilize SMART health information to assess hundreds of thousands of their own Hard Drives (I started using SMART to analyze drives on PPC Macs....actually had to compile the utility for macOS 10.4 since it was rare for a pre-compiled binaries to be available until many years later). My own built up acquired knowledge actually matched what I later read in the BackBlaze Hard Drive reports starting in 2013 even though I had a much smaller sample size to assess. Other than the articles posted by BackBlaze, I have never seen any overall good articles explaining any of this.....my post here may be a first, but I am restricted by the forum's character limitations and formatting options as well as my desire to try & keep it very "basic".

With this basic understanding of the information presented in the SMART attribute table of the DriveDx report, you can re-examine those entries to see how none of those attributes DriveDx marked as "Warning" & "Failing" really are still within the limits expected by the drive's manufacturer when you look at the "Value", "Worst", and "Threshold" columns. Unlike Hard Drives, SSDs can actually keep working relatively unscathed when these attributes decline. The only real issue is all of the reported write errors which are a cause of concern if they are allowed to continue unchecked. And you mentioned that your SSD is having performance issues which is expected when the SSD must deal with those write errors.

With your SSD the attributes which are most concerning in their decline are the "Pre-Fail" ones where several of them are shown to be around 76% .... "Worst" has a reading of 79 (typically many attributes start at a Normalized number of 100 so considering 100 down to a threshold of 10 gives you the 76% number calculated by DriveDx to make it more understandable to the average user).

If it were my SSD.....I would definitely risk performing a hardware secure erase on this SSD to reset it to factory defaults. Depending on how this particular SSD handles errors sooner or later you may actually start to see your data corrupted. Currently the SSD is using ECC to correct for those errors, but there is likely to be a limit (perhaps attribute #195 which is currently at 73% from when it was new).

Your SSD would be a good candidate for a hardware reset to factory defaults. This type of behavior is similar to what I've seen with some other SSDs within my organization.

There is always a bit of a risk to using the SSD's built-in hardware secure erase feature to reset the SSD to factory defaults. The Linux utility only activates the existing built-in hardware feature....that is all. The SSD itself perform the actual reset to factory defaults. Of course if the hardware issue is such that the process has a problem or if the SSD's firmware has a bug in this area, then it could potentially brick the SSD.

All of the "Warning" and "Failing" notices in your DriveDx report is basically DriveDx assessing the SSD like a traditional Hard Drive. With a Hard Drive, all of the changes in those SMART attributes would indeed deserve those designations & I would recommend replacing the drive if it were a Hard Drive due to how Hard Drive failures generally behave & progress.

However, with an SSD I only take those DriveDx notices as a sign to manually examine the SSD's health attributes to see what is going on with the SSD. This is because DriveDx treats any change in value for most of the SMART health attributes as being bad so it alerts the user with a "Warning" or "Failing" notice for that attribute depending on how DriveDx perceives that attribute. These "Warning" & "Failing" notices are interpretations & annotations added by DriveDx and are not part of the usual designations from the SMART health log itself.

The table of SMART attributes contains two ways of looking at the health data. The manufacturer uses the "Value", "Worst", and "Threshold" column/items to indicate the health of the drive and when those attributes have exceeded the manufacturer's expectations which will alert an OS or utility monitoring the SMART status flag of a drive. These three values are Normalized values which generally start high & decline as the drive is used. When the "Worst" goes below (beyond may be a better word) the "Threshold" then SMART will flag the drive with a "Failed" SMART status. This is only done for the attributes designated as "PreFail". The attributes designated as "OldAge" or "LifeSpan" will never have "Value" or "Worst" go beyond the "Threshold" (the Normalized number never goes below one and most LifeSpan attributes will have a "Threshold" of zero which will never be reached. Those LifeSpan attributes don't necessarily mean the drive is bad.....just that it may be near the point where the drive may be worn out. Kind of like the difference between low oil leading to a seized engine and having high mileage on the car.

The column "Raw Value" may contain the actual count of event changes for that attribute, but for other attributes the "Raw Value" is meaningless since the manufacturer doesn't explain how the data with the "Raw Value" should be interpreted (in other words it may contain a grouping of several values & that grouping is only known by the manufacturer). The "Raw Value" is really more for a user to actually see the changes at a more granular level for some of those attributes where the "Raw Value" actually has useful meaning to people. An example is to see the number of bad blocks which is more understandable to humans. The "Raw Value" is converted to a Normalized "Value" which I mentioned in the previous paragraph. So X increments of a "Raw Value" will cause the Normalized "Value" to change by an increment of one (usually by a decrease).