I know SSD’s are not meant for data backup, but I do have an external SSD drive that I only plug and use occasionally. I know from research that the data should still be fine at least a year, so I should plug it in no less than that. But… apart from plugging it in, do I need to do anything or will the controller just magically refresh everything? In that case: how long does it need to be powered for this to be completed? Some say you need to actually read through all data, or even re-write it all, however that would be possible on a system drive.
What gives? It’s really hard finding some solid advice googling the matter.
I would be impossible to guess without a knowledge of internal working of a particular SSD. For a NAND-specific file system I’ve implemented (not SSD but a device using raw SLC NAND) there was a block refresh immediately after ECC error detection at read and also background process checking slowly all the pages in use (one week for a full cycle). Background scan was starting each time after powering on from a randomized point.