SSD manage read/write with bad blocks?

rockman413

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Apr 7, 2017
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#1
Hi there,

How does SSD manage read/write with bad blocks? Will it automatically skip bad blocks and write to good blocks?

How about an SSD good block/sector has been written already, then that already-written sector turns bad, it will not be readable? Or it will still be readable, but you're going to get incomplete info/ corrupted file?
 
Solution
hard drives use megnict medium to read...there bad blocks are writen to a file not to be used. on a ssd your writting to a memory chip. if the chip goes bad the ssd firmware will not use that chip.
Every ssd block has a finite number of updates. About 10,000 I think.
The ssd firmware is very familiar with this and manages updates to wear evenly.
Implementing "trim" is one of the techniques to do this.
Some number of blocks are reserved from the advertised capacity.
If a block can no longer be updated, it is taken out of service.
Ultimately, if all the blocks are no longer capable of being updated, the ssd can still be read.

Not to worry, though, a 240gb ssd in very heavy desktop operation will become obsolete long before it wears out.
 
My concern is:

No matter how bad the condition a SSD is, now matter how many bad sectors are in there,as long as we can copy files out of it, can we be sure that the copied files are not corrupted at all? If one sector turns bad, are we going to get an error message while copying or not? Are we going to get corrupted files?

I heard if such happens to HDD, we can get corrupted files when copying from it.
 
How about a chip/sector/block goes bad caused by physical dropping of the SSD/ shocking? Will the firmware know it's bad and skip writing to it?

How firmware work? scan all sector upon start-up ?
 

No, not same question, this relates to :
http://www.tomshardware.com/answers/id-3558668/replace-ssd.html

It's about if any physical shocking/damage to a clip/sector and firmware will know and when writing, firmware will skip that , then I don't have to replace my SSD.
Or firmware only record/note bad sector when it is running, meaning at power off status any physical damage will not be noted by firmware of SSD