Mastodawn

Graham Sutherland / Polynomial May 26, 2024

SD cards are the literal worst.

they've expanded to be the size of small hard drives, and devices like the rpi keep using them as boot media, but they:

- use garbage tier low endurance flash cells internally
- have little to no overprovisioning for wear
- perform only the most basic wear levelling
- have no protocol level integrity checking
- have few internal error correction features, if any
- decay comparatively quickly without patrol scrubs
- do not perform patrol scrubs
- cannot do PLP

Show thread

Graham Sutherland / Polynomial May 26, 2024

I've been mad about this pretty much forever. Don't use SD cards for stuff where there's literally any other option.

Show thread

Alanna 🏳️‍🌈🏳️‍⚧️May 26, 2024

@gsuberland I agree with you, but what other options are there at the moment? I guess USB drives might work.

Show thread

Graham Sutherland / Polynomial

@kelpana USB flash drives are better, although still have issues. CompactFlash is ok, SATA/UAS or NVMe is preferred where you can (but obviously much more complex). For stuff where you only need firmware and a small amount of persistent storage (e.g. for a config block) it can make more sense to use EEPROMs and select parts that meet your longevity needs, and implement your own wear levelling / scrubbing where needed.