> On Jan 31, 2023, at 8:38 PM, Warner Losh via cctalk <cctalk@classiccmp.org>
> wrote:
>
> On Tue, Jan 31, 2023, 5:03 PM Ali via cctalk <cctalk@classiccmp.org> wrote:
>
>>> I thought Flash could only hold the data in them X amount of years
>>> until
>>> the junctions discharge or whatever? It's less permanent than decent
>>> quality optical or pro magnetic media?
>>>
>>> You have to plug them in every so often to refresh I believe.
>>
>> Does REFRESHING mean reread and rewrite or just keep power to it? If it's
>> the latter it should be trivial to setup a system with backup battery just
>> to supply voltage to a bunch of SSD drives.
>>
>
> It depends on the drive's firmware. Some do background scans of blocks
> while idle. Others do not. Since you have no way of knowing which is which
> (or even when the backgroundscan is done), the safest way to force a scan
> is to read the whole drive... any blocks whose raw error count is too high
> will be rewritten to fresh blocks. If it's a good SSD you'll likely not
> notice this happening. If it's a crappy thumb drive... you may be better
> off copying to some other media..
>
> Warner
Do you know what the likely answer is for "memory sticks", SD or MicroSD cards,
things like that? I assume their firmware is tiny, so are they likely to need
active refreshing?
paul
