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Comment by elAhmo | Hacker News Reader

Is ECC RAM that much valuable in day to day for non-critical usages?

Short: Yes, but of course it depends. Long: I am dealing with a huge amount of fitness related health data which gets aggregated into metrics. If those metrics are wrong, for whatever reason, this is not great.

If you just run some blogs, of course, this is not important.

I’ve had it catch a bunch of errors on borderline memory at home. (Despite the memory passing memtests).

Just to throw it out there, surely we've ruled out ECC RAM gets away with worse modules because the checking bit will catch it? Because I actually tried to generate bit flips for a project once and we got nothing. Also a relatively high traffic site, registering a few bit flip variants (so like example.com -> fxample.com) got no hits whatsoever across a year. I keep seeing reports from people with ECC or people who found an available bit flip variant of a top X website, but it never happens to me on normal RAM. I can't imagine that ECC vendors are selling worse RAM with a check bit, but the more I read the more I wonder if maybe we should check just to be sure

> Just to throw it out there, surely we've ruled out ECC RAM gets away with worse modules because the checking bit will catch it?

Doubtful. With proper support, you get reports/counts per bitflip. Most people will swap out ram that has any detected bitflips or with a small number anyway. And if you have a significant number, the machine check interupts really kill perf anyway.

It’s quite possible that they’re worse but I doubt it.

If you have one product line where error will go undetected and another where it will be visible to the user (and result in returns) the manufacturer incentive is in the opposite direction as what you describe

The risk of bit flips is a percentage. The more RAM you have, the greater the likelihood. I have experienced heisenbugs on my 64 GB desktop that I bet were because of random bit flips

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