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by mercora 1830 days ago
if that is true disks should come with a very visible note stating this... seriously, 3 months would be nothing. i doubt it is true because 3 months is a time frame which should be surpassed quite often making this more known.
5 comments

Three months is the minimum standard for data retention from an enterprise SSD that has used up its entire write endurance and reached end of life, but is still being stored in a hot chassis.

Outside of that narrow scenario, the three months figure is wildly wrong and should not be repeated. Lower temperatures, a consumer drive, and not having used up 100% of the write endurance will all drastically lengthen data retention.

(However, under no circumstances should you trust a cheap USB thumb drive to retain your data. Those tend to use lower-grade flash memory and lower-quality controllers. If you need an external device to reliably cart around data, shop for a "portable SSD", not a "USB flash drive".)

Depending on manufacturer, and storage conditions, it can be up to about ten years. But the “three months” number is real: https://web.archive.org/web/20210502042514/http://www.dell.c...
That's a document from nine and a half years ago, and it states:

> It depends on the how much the flash has been used (P/E cycle used), type of flash, and storage temperature. In MLC and SLC, this can be as low as 3 months and best case can be more than 10 years. The retention is highly dependent on temperature and workload.

Are there any modern sources provide more accurate stats? "3 months to 10 years" is so vague as to be useless.

Consumer SSDs (unlike enterprise SSDs) must have a retention time of at least 1 year at the end of their life.

To achieve that target, when they are new they must have a retention time of a few years, but you should better not count on that.

Yep, they are semivolatile limited write memory modules, not disks. Everyone should use that SV-LWMM acronym.
It occurs to me now that the key word here may be “unpowered”. As in, if you unplug an SSD and leave it on the shelf, it may lose (some) data in as little as three months. There might not be many people who do that, and those who do might not notice the occasional corruption.
Is this an actual useful application if optane, replacing the memory with near-ram nonvolatile ?