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Igor_Kavinski
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Block wear leveling count S.M.A.R.T. value

Tue Nov 26, 2019 10:39 am

The Block wear leveling count S.M.A.R.T. value for my workplace SSD is 38. Does this mean that the entire drive has been written 38 times over? Or does this value indicate something else?
 
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Re: Block wear leveling count S.M.A.R.T. value

Tue Nov 26, 2019 10:58 am

If you're talking about the raw value, it's a cycle count. If you're talking about the current/worst value, it's a figure that starts at 100 and drops to 0 over the life of the drive.
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Re: Block wear leveling count S.M.A.R.T. value

Tue Nov 26, 2019 11:02 am

Are you looking at the raw value, or the normalized value? For many SMART attributes, the raw value is vendor/model-specific. The normalized value typically (but not always) starts at 100 and counts down towards 0 as the drive wears out or fails.

In this case, the raw value is PROBABLY either an average or a worst-case of the number of times each flash block has been erased and reprogrammed. Assuming it really is the number of program/erase cycles, a value of 38 isn't bad, with the possible exception of first-gen QLC flash (which had rather low write endurance).

OTOH, if it's a normalized SMART value, then the drive has 38% of its rated write endurance left (i.e., it's 62% worn out).

Edit: Waco beat me to it! :lol:
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Igor_Kavinski
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Re: Block wear leveling count S.M.A.R.T. value

Tue Nov 26, 2019 2:26 pm

I'm not sure if it is raw or normalized value. However, the drive life remaining value is at 97% (it was 100% when new) so that means it must be a raw value and will increase to whatever maximum erases are possible for the available flash cells?
 
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Re: Block wear leveling count S.M.A.R.T. value

Tue Nov 26, 2019 2:43 pm

Igor_Kavinski wrote:
I'm not sure if it is raw or normalized value. However, the drive life remaining value is at 97% (it was 100% when new) so that means it must be a raw value and will increase to whatever maximum erases are possible for the available flash cells?

Yup. And 38 sounds about right for 97% life remaining, assuming the flash endurance is ~1,000 cycles.
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