I'm not sure there's any guarantee that it will ever be sorted, since bit flips will be random and are just as likely to put it more out of order than more in order. Plus if there's any error correction going on, it can cancel out bit flips entirely until up to a certain threshold.

Though I'm not sure if ECC (and other methods) write the corrected value back to memory or just correct the signals going to the core, so it's possible they could still add up over time and overcome the second objection.

[–] dan@upvote.au 2 points 1 week ago

ECC (and other methods) write the corrected value back to memory

That was my understanding (it corrects the error and writes the good value back to RAM), but now I'm not so sure! I imagine it must do that, otherwise a second bit flip would actually corrupt the RAM, and the RAM manufacturer would want to reduce that risk.

Regular ECC adds an extra parity bit for each byte. For each byte of memory, it can correct an error in one bit, and detect but not correct an error in two bits, so they wouldn't want a one bit error to linger for longer than it needs to.

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