please help translate smartctl output to human language

[Domagoj Smolčić]

On Thu, 18 Jul 2019 21:29:55 +0200 (CEST)
Wojciech Puchar <wojtek at puchar.net> wrote:

> i am interested how much write-wear does my samsung SSD experienced 
> relative to maximum allowed.
> 
> on my 500GB samsung SSD smartctl says
> 
> ID# ATTRIBUTE_NAME          FLAG     VALUE WORST THRESH TYPE
> UPDATED WHEN_FAILED RAW_VALUE
>    5 Reallocated_Sector_Ct   0x0033   100   100   010    Pre-fail
> Always 
> -       0
>    9 Power_On_Hours          0x0032   093   093   000    Old_age
> Always 
> -       31126
>   12 Power_Cycle_Count       0x0032   099   099   000    Old_age
> Always 
> -       59
> 177 Wear_Leveling_Count     0x0013   095   095   000    Pre-fail
> Always 
> -       88
> 179 Used_Rsvd_Blk_Cnt_Tot   0x0013   100   100   010    Pre-fail
> Always 
> -       0
> 181 Program_Fail_Cnt_Total  0x0032   100   100   010    Old_age
> Always 
> -       0
> 182 Erase_Fail_Count_Total  0x0032   100   100   010    Old_age
> Always 
> -       0
> 183 Runtime_Bad_Block       0x0013   100   100   010    Pre-fail
> Always 
> -       0
> 187 Uncorrectable_Error_Cnt 0x0032   100   100   000    Old_age
> Always 
> -       0
> 190 Airflow_Temperature_Cel 0x0032   073   051   000    Old_age
> Always 
> -       27
> 195 ECC_Error_Rate          0x001a   200   200   000    Old_age
> Always 
> -       0
> 199 CRC_Error_Count         0x003e   100   100   000    Old_age
> Always 
> -       0
> 235 POR_Recovery_Count      0x0012   099   099   000    Old_age
> Always 
> -       28
> 241 Total_LBAs_Written      0x0032   099   099   000    Old_age
> Always 
> -       115175140988
> 
> 
> 
> 
> All seems fine but i'm not sure if i correctly understand VALUE,
> WORST, THRESH data for Total_LBAs_Written
> 
> 50TB was written, so it's 100 times capacity. taking some write 
> amplification in account (i use geli so no in drive compression have 
> effect) it would be probably like 150-200.
> 
> Value is 99. It was 100 when i bought it.
> 
> Does it mean that in is 1% worn and can take 100 times more writes
> until it fails? or i am too optimistic?
> _______________________________________________
> freebsd-hackers at freebsd.org mailing list
> https://lists.freebsd.org/mailman/listinfo/freebsd-hackers
> To unsubscribe, send any mail to
> "freebsd-hackers-unsubscribe at freebsd.org"


Integers representing VALUE, WORST and THRESH columns are "normalized values".
Over time, VALUE of Total_LBAs_Written will be declining.
Once it reaches THRESH value it is considered 'Old_age', meaning it's prone
to all kinds of malfunctions expected from old hardware.
That doesn't mean you want be able to use it afterwards.


Domagoj Smolčić