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A comment on The unpowered SSDs in your drawer are slowly losing your data. Parent comment

Re:The unpowered SSDs in your drawer are slowly losing your ... by gruez on Monday November 24, 2025 @07:25PM (#46041012)
>Generally, the data refresh will all happen in the background when the system is powered (depending on the power state).

How does the SSD know when to run the refresh job? AFAIK SSDs don't have an internal clock so it can't tell how long it's been powered off. Moreover does doing a read generate some sort of telemetry to the controller indicating how strong/weak the signal is, thereby informing whether it should refresh? Or does it blindly refresh on some sort of timer?

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Re:The unpowered SSDs in your drawer are slowly losing your ... by fairfeather on Monday November 24, 2025 @10:36PM (#46042102)
Pretty much, but it depends a lot on the vendor and how much you spent on the drive. A lot of the assumptions about enterprise SSDs is that they’re powered pretty much all the time, but are left in a low power state when not in use. So, data can still be refreshed on a timer, as long as it happens within the power budget.

There are several layers of data integrity that are increasingly expensive to run. Once the drive tries to read something that requires recovery, it marks that block as requiring a refresh and rewrites it in the background.

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Re:The unpowered SSDs in your drawer are slowly losing your ... by rasz on Monday November 24, 2025 @11:26PM (#46042326)
https://www.techspot.com/news/60501-samsung-addresses-slow-8...

samsung fix was aggressive scanning and rewriting in the background

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