2 ms·
> Disks have ECC, even consumer hard drives have checksummed blocks, that's how you get media errors detected. RAM does not. Well, technically with DDR5 it has
by marginalia_nu 3y ago
> Disks have ECC, even consumer hard drives have checksummed blocks, that's how you get media errors detected. RAM does not. Well, technically with DDR5 it has internal one but it does not give any feedback to the machine so you might not know your RAM has any problems.
Sure, and disks have random errors even with error correction. Adding hamming codes just makes errors less likely and easier to detect, but they aren't fool proof, in ram or on disk or anywhere else. The protection offered is a bit questionable because they rely on the very sketchy assumption that errors are statistically independent events, which is rarely how storage errors work.
> But it will tell you the problem
> Very ignorant take
Hardware isn't perfect. No matter how much error correction you pile onto it, you will still have errors and some cases will still be undetectable. It's a matter of pushing the rate of errors into an acceptable range, as a pure cost-benefit tradeoff, statistics through and through.