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Comment by ac29 | Hacker News Reader

"Nope, personal experience. SD cards have wear leveling, EMMC generally doesn't, so if using them for the same thing, the EMMC will fail first. depends on the FS." - An Engineer at Rasberry Pi.

Anyone comment on that?

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Average users aren't running out of write cycles. SD cards usually corrupt themselves and can be reflashed multiple times before they become physically unusable. If you are willing to pay a premium then you can get a more reliable brand but there are no guarantees that the specific model you bought is reliable. Usually corruption happens in combination with sketchy micro USB cables and power adapters (micro USB compatibility isn't actually a great benefit). Smartphones have batteries so the only thing that matters is that the average power sent to the battery exceeds the discharge rate. A temporary voltage drop for a fraction of a second can ruin the stability of your SBC and corrupt the SD card in the process. eMMC is non replaceable, therefore it has to be more resistant against power loss. Corrupting eMMC can turn the entire device into a paperweight.

It 100% comes from not enough amps from a power supply. The Pi will run on less than 2000ma but at some point you are going to start getting transistor level bit flips not unlike a CPU that is overclocked too high. Things like cell phone chargers also appear to work but simply cant supply a consistent current under load because they were never designed to

Its an incorrect statement - I think James on the Pi forum was confusing NAND vs eMMC.

eMMC has (with exception of some high grade SDCards) better write cycles and is considerably more durable than the average SDCard.

What about above average SD cards: the so called "industrial" SD cards?

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