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Comment by lmns | Hacker News Reader

SD cards with wear leveling and error correction are hard to find and can easily be more expensive than similar SSDs.

I was under the impression most non-awful SD cards had some sort of wear-leveling these days but there's no standard for it so they don't advertise it on the front like SSDs. I couldn't really find any proof either-way about this, just a few instances of people looking into it:

- https://electronics.stackexchange.com/questions/27619/is-it-... - https://www.reddit.com/r/raspberry_pi/comments/ex7dvo/quick_...

I think every microSD and USB sticks by now has WL across the board, especially at awful grade. WL and ECC are must at current [price, BER, capacity, bit-per-cell] or something.

With USB sticks it's a different story. There are some manufacturers like Sandisk who claim they use wear leveling in all of their current USB sticks.

microSD is a mess in this regard. Wear leveling is less common there and only present in very specific and expensive niche models.

[citation needed]. I can’t believe any but the cheapest no-name SD cards would have absolutely no form of wear leveling.

It does look like there are many of cards that don't claim any sort of wear leveling (doesn't mean they don't do it at all but they don't call it out). This is surprising to me, but if you want to make sure you get a card with wear leveling, look for it in the specs. These SanDisk industrial cards[1] are ones I've used in the past that specifically claim they do wear leveling in the spec sheet: Advanced memory management FW features power immunity, auto/manual read refresh, ECC, wear leveling. They're also only a few bucks more than a "normal" microSD card.

[1]https://www.amazon.com/SanDisk-Industrial-MicroSD-UHS-I-SDSD...

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