Exceeding boot drives rated write life ok?

[StarsMars]

I have exceeded my boot drive rated write life.

I have a Samsung 850 evo 250gb, which is rated for 75tbw. Samsung magician says I am at about 105tbw health "good".

It's from my 2016 build that I've carried over.

 

Should I be concerned or considering transferring to another drive?

I assume they tend to go well past their rating

[jaslion]

Basically what that means is it is now in the untested for ranges so it could fail whenever or keep going for years. They do go a fair bit past their rating but you are already a fair bit past it :p. Using it as a scratch drive or something?

 

Basically keep a backup of the drive for when it fails.

[mariushm]

It's more or less like this ... The flash memory is arranged in blocks, for example 24 MB chunks. It's not the writes that wears out a SSD, it's the erases of blocks to make the pages inside the blocks writable again that causes damage to those blocks. 

They have an estimate of how many erases can be done on blocks until they're no longer reliable, until they have difficulty reading back data from pages reliably, with a low enough error rate. Once there's too many errors and block is deemed too unreliable, the block becomes read only and in theory the controller will copy the data to another block and mark this unreliable block so it won't be used anymore.  

Some number of erases varies depending on die quality and lots of other things, some blocks could last 3500 erase cycles, some could last 4000 ... the manufacturer will most likely be conservative and calculate warranties with a number like 3000 for example. 

 

Your particular SSD ... 75 TB on 250 GB is more or less 300 erase cycles ... some blocks will be erased more , some less ... if it's TLC memory, I would say at least 500 erase cycles is a safe number so I'm not surprised the drive did 105 tb ... that's still less than 450 erase cycles.

 

See https://en.wikipedia.org/wiki/Flash_memory#Write_endurance

 

You'll see there 3D TLC NAND as in your SSD estimated to have between 1000 and 3000 erases per block, and if you check the SMART data for your drive, your erase counter is probably in the 500 range.

   

[StarsMars]

12 hours ago, jaslion said:

Basically what that means is it is now in the untested for ranges so it could fail whenever or keep going for years. They do go a fair bit past their rating but you are already a fair bit past it :p. Using it as a scratch drive or something?

 

Basically keep a backup of the drive for when it fails.

Is it a risk or will SMART give me a warning?

I don't know if that's something to expect or more of a possible protection

 

12 hours ago, mariushm said:

It's more or less like this ... The flash memory is arranged in blocks, for example 24 MB chunks. It's not the writes that wears out a SSD, it's the erases of blocks to make the pages inside the blocks writable again that causes damage to those blocks. 

They have an estimate of how many erases can be done on blocks until they're no longer reliable, until they have difficulty reading back data from pages reliably, with a low enough error rate. Once there's too many errors and block is deemed too unreliable, the block becomes read only and in theory the controller will copy the data to another block and mark this unreliable block so it won't be used anymore.  

Some number of erases varies depending on die quality and lots of other things, some blocks could last 3500 erase cycles, some could last 4000 ... the manufacturer will most likely be conservative and calculate warranties with a number like 3000 for example. 

 

Your particular SSD ... 75 TB on 250 GB is more or less 300 erase cycles ... some blocks will be erased more , some less ... if it's TLC memory, I would say at least 500 erase cycles is a safe number so I'm not surprised the drive did 105 tb ... that's still less than 450 erase cycles.

 

See https://en.wikipedia.org/wiki/Flash_memory#Write_endurance

 

You'll see there 3D TLC NAND as in your SSD estimated to have between 1000 and 3000 erases per block, and if you check the SMART data for your drive, your erase counter is probably in the 500 range.

   

 

Seems fine but I don't totally know what I'm looking at.

I'll probably clone to my nvme here soon.

 

[mariushm]

29 minutes ago, StarsMars said:

Is it a risk or will SMART give me a warning?

I don't know if that's something to expect or more of a possible protection

 

 

Seems fine but I don't totally know what I'm looking at.

I'll probably clone to my nvme here soon.

So basically wear leveling count = 455  - that's probably average wear leveling across flash memory cells ... some blocks will probably be a bit higher, others a bit less.

Like the wikipedia link says, the erase cycles is within 1000....3000 for TLC used in drives like yours

 

The rest looks good... a single block was invalidated and had data moved somewhere else (you see that in "Reallocated Sector Count" and "Used Reserved Block Count (total)" )

 

29 minutes ago, StarsMars said:

 

 

[StarsMars]

17 hours ago, mariushm said:

So basically wear leveling count = 455  - that's probably average wear leveling across flash memory cells ... some blocks will probably be a bit higher, others a bit less.

Like the wikipedia link says, the erase cycles is within 1000....3000 for TLC used in drives like yours

 

The rest looks good... a single block was invalidated and had data moved somewhere else (you see that in "Reallocated Sector Count" and "Used Reserved Block Count (total)" )

 

 

Thank you. I'll backup my data and migrate it soon.

[StarsMars]

Swapped to an nvme drive in the system. Will hold the old one for a spare system

 

thanks again