Wear-leveling peculiarities

[Richard Weinberger]

Am 26.05.2015 um 11:38 schrieb Johannes Bauer:
> Am 18.05.2015 22:47, schrieb Richard Weinberger:
> 
>>>> I suspect that your threshold was never reached.
>>>
>>> Yes, I suspect you're right here.
>>
>> If you did not set CONFIG_MTD_UBI_WL_THRESHOLD it is 4096.
>> So, regular wear-leveling did never happen.
> 
> Your initial assessment was correct. The WL_THRESHOLD is at 4096 when we should have configured it to a lower value for our NAND flash.
> 
>> The OOB-Data does not matter. UBI is not using OOB.
>>
>> So, you have to figure out why UBIFS is dying. Maybe it is a NAND issue.
> 
> Yes, sorry, I meant the EC header metadata. Indeed it looks like our NAND flash is dying because WL is not active. Determining the amount of erase-cycles of dead NAND blocks is
> difficult (since the EC header meatdata is lost as well when the whole block doesn't respond anymore).

What flash is this?
I should not start dying that early.

Thanks,
//richard