Periodic refresh (or rwrite?) of data on an SSD (was: Re: Recommended SSDs and 4-bay internal dock)
On Wednesday, January 11, 2023 12:20:05 PM Linux-Fan wrote:
> > Or does one need to read every byte, allocated or not?
>
> AFAIK one needs to _power_ the device every once in a while and keep power
> connected for some time. Then, the controller can dos all the necessary
> actions in the background.
...
> Here is an article from 2021 that shows some typical numbersas I
> remembered them. I do not know anything about this specific source's
> credibility, though:
> https://www.virtium.com/knowledge-base/ssd-data-retention/
>
> This entry seems to be rather pessimistic:
> https://www.ibm.com/support/pages/potential-ssd-data-loss-after-extended-sh
> utdown
I've read some of that article, or, I guess, really the abstract and the
section labeled "Content" on that page:
https://www.ibm.com/support/pages/potential-ssd-data-loss-after-extended-
shutdown
I see the statement: "A system (and its enclosed drives) should be powered up
at least 2 weeks after 2 months of system power off. If a drive has an error
indicating it is at end of life we recommend not powering off the system for
extended periods of time.", and the first quoted paragraph in this email
reiterates the need to power up occasionally and leave connected for some time
(so that the controller can do all the necessary actions in the background).
I assume that they are talking about the hardwired controller built into the
drive, thus there is no particular need to power it up from an OS that
recognizes it but simply something that powers it somehow?
Can anyone shed more light on what happens during that two weeks -- is the
data somehow "refreshed" (in place), or rewritten somewhere else on the drive,
or ???
(Perhaps that is discussed in the complete article of which this appears to be
just the abstract??)
Thanks!
--
rhk
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