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#52267 - 08/19/19 11:33 PM Re: SSD fails SMART [Re: freelance]
artie505 Online


Registered: 08/04/09
I kinda screwed up my earlier reporting, but, happily, not beyond redemption. Thanks for nudging me in the right direction.

First, the app joemike inquired about is SAT SMART Driver, and these are the DriveDx and Micromat pages on the subject; the DDx page includes a d/l link.

The first time I installed it I couldn't find anything to do in System Prefs, it didn't work, and I somehow got a "You're out of luck!" pop-up.

After reading your post, though, I installed it again, and again couldn't find anything to do in System Prefs, but this time it occurred to me to unmount/mount my external (DOH!), and VOILA!

Second, both of us have confused the issue a bit by posting only the complete reports that joemike and I find so cumbersome, so here are the actual GUI aspects of DDx's reports on my internal and external SSDs. (The small shots are expanded views of the collapsed General Information sections of the large shots above them.)

It now appears to me that DDx and DS are almost identical apps, although with obviously necessarily differing GUI aspects, and unless joemike sees any real down side to its functionality I'm going to buy it for $20 rather than SD for $30, not only to save myself $10, but to stick it to Micromat for what may easily be considered extreme overcharging, i.e. $50 if you haven't got a Micromat serial #.

And finally, in a different vein, it's interesting to note the difference between the DRIVE HEALTH INDICATORS and IMPORTANT HEALTH INDICATORS reported by DDx for my internal (Apple (Samsung-based) g-series SSD) and external (SanDisk Marvell-based SSD) drives:

Internal:

=== DRIVE HEALTH INDICATORS ===
ID | NAME | TYPE | UPDATE | RAW VALUE | VALUE | THRESHOLD | WORST | LAST MODIFIED | STATUS
1 Raw Read Error Rate Life-span online 0x0 200 0 200 - 100% OK
5 Retired Block Count Pre-fail online 0 100 0 100 - 100% OK
9 Power On Hours Life-span online 28,181 94 0 94 8/19/19 10:17 PM 94.0% OK
12 Power Cycle Count Life-span online 952 99 0 99 - 99.0% OK
169 Total Bad Block Count Pre-fail online 0x3390A800780 242 10 242 - 100% OK
173 Wear Leveling Count Life-span online 0x800900049 196 100 196 - 96.0% OK
174 Host Reads MiB Life-span online 17,622,696 (16.8 TB) 99 0 99 8/19/19 10:17 PM 99.0% OK
175 Host Writes MiB Life-span online 13,845,735 (13.2 TB) 99 0 99 8/19/19 10:17 PM 99.0% OK
192 Unsafe Shutdown Count Life-span online 98 99 0 99 - 99.0% OK
194 Temperature (Celsius) Life-span online 35 65 30 19 - 50.0% OK
197 Current Pending Block Count Life-span online 0 100 0 100 - 100% OK
199 UDMA CRC Error Count Life-span online 0 200 0 200 - 100% OK

=== IMPORTANT HEALTH INDICATORS ===
ID NAME RAW VALUE STATUS
5 Retired Block Count 0 100% OK
173 Wear Leveling Count 0x800900049 96.0% OK
175 Host Writes MiB 13,845,735 (13.2 TB) 99.0% OK
192 Unsafe Shutdown Count 98 99.0% OK
197 Current Pending Block Count 0 100% OK
199 UDMA CRC Error Count 0 100% OK

External:

=== DRIVE HEALTH INDICATORS ===
ID | NAME | TYPE | UPDATE | RAW VALUE | VALUE | THRESHOLD | WORST | LAST MODIFIED | STATUS
5 Retired Block Count Life-span online 0 100 0 100 - 100% OK
9 Power On Hours Life-span online 5,071 253 0 100 - 100% OK
12 Power Cycle Count Life-span online 638 100 0 100 - 100% OK
166 Min Write/Erase Cycle Life-span online 1 100 0 100 - 100% OK
167 Min Bad Block/Die Life-span online 53 100 0 100 - 100% OK
168 Maximum Write/Erase Cycle Count Life-span online 53 100 0 100 - 100% OK
169 Total Bad Block Count Life-span online 0x3DF 100 0 100 - 100% OK
171 Program Fail Count Total Life-span online 0 100 0 100 - 100% OK
172 Erase Fail Count Total Life-span online 0 100 0 100 - 100% OK
173 Average Write/Erase Count Life-span online 10 100 0 100 - 100% OK
174 Unexpected Power Loss Count Life-span online 298 100 0 100 - 100% OK
184 End-to-End Error Life-span online 0 100 0 100 - 100% OK
187 Reported Uncorrectable Errors Life-span online 0 100 0 100 - 100% OK
188 Command Timeout Life-span online 0 100 0 100 - 100% OK
194 Temperature (Celsius) Life-span online 34 66 0 50 - 66.0% OK
199 SATA CRC Error Life-span online 0 100 0 100 - 100% OK
212 SATA Error Count Handshake Life-span online 0 100 0 100 - 100% OK
230 Percentage Total P/E Count Life-span online 33 100 0 100 - 100% OK
232 Available Reserved Space Pre-fail online 0x64 100 4 100 - 100% OK
233 Total NAND Writes Life-span online 5,725 (5.6 TB) 100 0 100 - 100% OK
241 Lifetime Writes Life-span offline 3,307 (3.2 TB) 253 0 253 - 100% OK
242 Lifetime Reads Life-span offline 3,515 (3.4 TB) 253 0 253 - 100% OK
244 Thermal Throttle Life-span online 0x0 0 0 100 - 100% OK

=== IMPORTANT HEALTH INDICATORS ===
ID NAME RAW VALUE STATUS
5 Retired Block Count 0 100% OK
168 Maximum Write/Erase Cycle Count 53 100% OK
230 Percentage Total P/E Count 33 100% OK
232 Available Reserved Space 0x64 100% OK
233 Total NAND Writes 5,725 (5.6 TB) 100% OK
241 Lifetime Writes 3,307 (3.2 TB) 100% OK

The differences between what the two manufacturers consider important may be telling to joemike, but it's meaningless to me.

Is more actually more, or is it less? crazy
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#52269 - 08/20/19 05:36 AM Re: SSD fails SMART [Re: joemikeb]
jchuzi Online


Registered: 08/04/09
Loc: New York State
I expect to receive my new SSD in a few days. In the meantime, I need to erase the defective SSD before discarding it. Is a simple erase sufficient for an SSD or should I use a 7-way erase?
_________________________
Jon

OS 10.14.6, iMac Retina 5K 27-inch, late 2014, 3.5 GHz Intel Core i5, 1 TB fusion drive, 16 GB RAM, Epson SureColor P600, Photoshop CC, Lightroom CC, MS Office 365

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#52270 - 08/20/19 06:04 AM Re: SSD fails SMART [Re: jchuzi]
joemikeb Online
Moderator

Registered: 08/04/09
Loc: Fort Worth, Texas
A simple erase erases ONLY the volume directory and leaves the data untouched. Granted the data is not as organized as it would be on an HD and therefore much harder to piece together, but given enoughvdesire, time, and money it is potentially recoverable. A 7 pass erase actually overwrites the data cells with alternating patterns of ones and zeros and I don't know if even an NSA level lab could recover it or not. I have read varying opinions on that but all agree someone would really have to want the data.
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#52271 - 08/20/19 06:41 AM Re: SSD fails SMART [Re: artie505]
joemikeb Online
Moderator

Registered: 08/04/09
Loc: Fort Worth, Texas
Originally Posted By: artie505
Is more actually more, or is it less? crazy

A valid question! My antipathy for the mimalist SMART pass/fail is based on two different drives that failed completely, but based on an aggregate SMART score Disk Utility still reported the drives had passed SMART. On the other hand, TechTool Pro showed one or more SMART attributes that had exceeded the limits and were being reported as FAIL.

Even if manufacturers set more realistic pass/fail limits for the SMART attributes the minimalist score still would only tell you if the drive had failed, and you probably already know or at least suspect that is the case. Having all the attributes permits an informed user to anticipate impending failure and perhaps short stopping a McGillicuddy's corollary to Murphy's Law event. The fly in this ointment is the word "informed".

In the final analysis the additional information is useless if the user does not understand what the attributes are telling her/him. It would be possible for an app to apply AI techniques to analyze the data, but then they risk being sued by drive manufacturers for saying a drive had failed or is failing when, as in the case of the two drives I mentioned, it still passes the manufacturer's overly optimistic failure criteria.

In the meantime I wish there were an app that would check the SMART values at a user specified and report not only changes in the attribute values, but the rate of change in selected key values. That would truly indicate impending failure. (I think I will write Micromat and suggest this as a new feature for Drive Scope.
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#52273 - 08/20/19 10:34 AM Re: SSD fails SMART [Re: joemikeb]
jchuzi Online


Registered: 08/04/09
Loc: New York State
According to Erase a volume using Disk Utility on Mac, a Secure Erase is not possible with an SSD. "With a solid-state drive (SSD), secure erase options are not available in Disk Utility. For more security, consider turning on FileVault encryption when you start using your SSD drive." I suppose that I could turn on FileVault encryption on the disk and not erase it(?)


Edited by jchuzi (08/20/19 10:36 AM)
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Jon

OS 10.14.6, iMac Retina 5K 27-inch, late 2014, 3.5 GHz Intel Core i5, 1 TB fusion drive, 16 GB RAM, Epson SureColor P600, Photoshop CC, Lightroom CC, MS Office 365

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#52275 - 08/20/19 02:46 PM Re: SSD fails SMART [Re: jchuzi]
joemikeb Online
Moderator

Registered: 08/04/09
Loc: Fort Worth, Texas
Note that is SECURE erase that is not available. You can erase/reformat an encrypted SSD, I did it just a few days ago but that was a simple erase that only erased the volume directory. The content of the drive remained as encrypted text which will be overwritten as the drive is used.

NOTES:
  1. Be forewarned: Filevault encrypts every sector on the drive, whether there is data in that sector or not, so it can take a long time — even days — to complete. You can continue to use the drive normally while encryption is going on but you will likely experience a slowdown in performance while it is happening.
  2. You can format a drive APFS (encrypted) or HFS+ (encrypted) and that will work if it is a data only volume.
  3. You cannot install MacOS on an empty volume formatted APFS (encrypted) or HFS+ (encrypted). You must make the initial installation on an unencrypted volume and THEN turn on Filevault to encrypt the volume
  4. You can upGRADE or upDATE an existing copy of MacOS on an encrypted volume.
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joemikeb • moderator

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#52276 - 08/20/19 04:14 PM Re: SSD fails SMART [Re: joemikeb]
jchuzi Online


Registered: 08/04/09
Loc: New York State
It appears that it is only possible to encrypt the boot drive with FileVault. Does that mean that I would have to boot from the defective SSD (it is a clone, after all) and then encrypt it? I'm thinking that it would be easier to drill several holes in the drive or, better yet, expose it to a nuclear blast. grin
_________________________
Jon

OS 10.14.6, iMac Retina 5K 27-inch, late 2014, 3.5 GHz Intel Core i5, 1 TB fusion drive, 16 GB RAM, Epson SureColor P600, Photoshop CC, Lightroom CC, MS Office 365

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#52278 - 08/21/19 12:53 AM Re: SSD fails SMART [Re: joemikeb]
artie505 Online


Registered: 08/04/09
Originally Posted By: joemikeb
Originally Posted By: artie505
Is more actually more, or is it less? crazy

A valid question!

<snip>

In the meantime I wish there were an app that would check the SMART values at a user specified and report not only changes in the attribute values, but the rate of change in selected key values. That would truly indicate impending failure. (I think I will write Micromat and suggest this as a new feature for Drive Scope.

And an excellent answer; thanks.

Your final point is so obvious, though, that I've got to wonder why such an app hasn't been developed yet; although it obviously couldn't provide definitive failure anticipation, it doesn't seem as if it would be a big deal to enable it to provide at least minimal proactive early warning functionality which would certainly surpass the functionality of Drive Scope and DriveDx.

But... You didn't actually answer the question I (thought I) really asked, namely, do the different mixes of SMART attributes reported for my Samsung and SanDisk SSDs give either report an edge in assisting me in anticipating drive failure?

And in a different vein, doesn't it seem odd that only one SMART attribute is reported for freelance's SSD?

=== DRIVE HEALTH INDICATORS ===
ID | NAME | TYPE | UPDATE | RAW VALUE | VALUE | THRESHOLD | WORST | LAST MODIFIED | STATUS
194 Temperature (Celsius) Life-span online 44 56 30 50 - 37.1% OK
_________________________
The new Great Equalizer is the SEND button.

In Memory Of Harv: Those who can make you believe absurdities can make you commit atrocities. ~Voltaire

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#52279 - 08/21/19 06:48 AM Re: SSD fails SMART [Re: artie505]
joemikeb Online
Moderator

Registered: 08/04/09
Loc: Fort Worth, Texas
Originally Posted By: artie505
<snip>

Your final point is so obvious, though, that I've got to wonder why such an app hasn't been developed yet; although it obviously couldn't provide definitive failure anticipation, it doesn't seem as if it would be a big deal to enable it to provide at least minimal proactive early warning functionality which would certainly surpass the functionality of Drive Scope and DriveDx.

I suspect part of the reason is SMART was playing second fiddle to surface scans and other indicators applicable to HDs. The resurgence of interest in SMART is fairly recent and is just now being fleshed out. 🤷‍♂️

Originally Posted By: artie505
But... You didn't actually answer the question I (thought I) really asked, namely, do the different mixes of SMART attributes reported for my Samsung and SanDisk SSDs give either report an edge in assisting me in anticipating drive failure?

Yes — if you understand enough about what they are reporting to interpret the attributes. There are a whole series of SMART attributes for hard drives and SATA connected SSDs that are intended to indicate a drive is in a "pre-failure" status, and others that indicate the age of the drive and both are so designated in the Drive Scope report. Whether a report indicates a parameter is a "pre-fail" indicator or not that attribute still indicates "pre-fail status". See Drive Scope HD Attributes. Any positive number in a pre-fail attribute is at least a caution flag. If a pre-fail attribute racks up half of the threshold value you should have the drives replacement on order and planning your switchover strategy. Typically the closer you get to a threshold value the faster the rate of deteriration.

Unfortunately NVMe drives do not have as rich a set of SMARY attributes. (See Drive Scope NVMe Attributes) but the Spares statistics are a good surrogate for "pre-fail" attributes and units Read and Written are a decent indicator of age while any NO in the Yes/No attributes indicates failure.

Originally Posted By: artie505
And in a different vein, doesn't it seem odd that only one SMART attribute is reported for freelance's SSD?

There are a LOT of reasons for that:
  • The drive is connected via USB and the USB standard does not allow for reporting SMART so he is getting the report via what is essentially a hack.
  • The enclosure is a two drive hardware RAID which is pretty much guaranteed to be either RAID 0 or RAID 1 and will be "seen" by the computer as if it were a single entity.
  • We have no idea what attributes the two drives in the enclosure report or whether the closure attachment is ATA or NVMe and it is doubtful the hack can sort that out.
  • I see the individual drives in my RAID array because the connection is Thunderbolt 2 which does provide for reporting SMART and I am using Software RAID so the data is read and written to individual drives and assembled into a single stream in the computer.


Edited by joemikeb (08/21/19 07:54 AM)
Edit Reason: hit return too soon
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#52321 - Today at 01:40 AM Re: SSD fails SMART [Re: joemikeb]
artie505 Online


Registered: 08/04/09
Originally Posted By: joemikeb
Originally Posted By: artie505
...do the different mixes of SMART attributes reported for my Samsung and SanDisk SSDs give either report an edge in assisting me in anticipating drive failure?

Yes — if you understand enough about what they are reporting to interpret the attributes. There are a whole series of SMART attributes for hard drives and SATA connected SSDs that are intended to indicate a drive is in a "pre-failure" status, and others that indicate the age of the drive and both are so designated in the Drive Scope report. Whether a report indicates a parameter is a "pre-fail" indicator or not that attribute still indicates "pre-fail status". See Drive Scope HD Attributes. Any positive number in a pre-fail attribute is at least a caution flag. If a pre-fail attribute racks up half of the threshold value you should have the drives replacement on order and planning your switchover strategy. Typically the closer you get to a threshold value the faster the rate of deteriration.

I think I"m beginning to understand this.

After looking through your report and my two (Damn design copyrights!), I"m left with these questions:
  1. I assume it's manufacturer option, but do you see any logic as to why some attributes are identified as "Pre-Fail" on one drive and "Life-Span/Old Age" on another?
  2. "Any positive number" in which column of your report?
  3. Would you please explain "If a pre-fail attribute racks up half of the threshold value" graphically? I don't follow it from what I've been looking at.

Originally Posted By: joemikeb
Originally Posted By: artie505
And in a different vein, doesn't it seem odd that only one SMART attribute is reported for freelance's SSD?

There are a LOT of reasons for that:
  • The drive is connected via USB and the USB standard does not allow for reporting SMART so he is getting the report via what is essentially a hack.
  • The enclosure is a two drive hardware RAID which is pretty much guaranteed to be either RAID 0 or RAID 1 and will be "seen" by the computer as if it were a single entity.
  • We have no idea what attributes the two drives in the enclosure report or whether the closure attachment is ATA or NVMe and it is doubtful the hack can sort that out.

The report on my SanDisk SSD was generated by the same "hack," and it appears to be complete.
_________________________
The new Great Equalizer is the SEND button.

In Memory Of Harv: Those who can make you believe absurdities can make you commit atrocities. ~Voltaire

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