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Comment by flaunf221 | Hacker News Reader

> You notice when things like your compressed files start giving CRC/checksum errors or your downloads don't match SHA-512.

And 9 times out of 10 (probably much more) it will be faulty storage, not RAM.

I'd say you are way overestimating impact of no-ECC.

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You need the ECC RAM for your filesystem with integrity only then can you be confident you aren't going to be familiar with a concept like this happening 9 or 10 times.

You can read online how often correctable errors happen to people with ECC and reporting.

Single digit - sometimes none - errors per year in systems with consumer amount of RAM.

Systems with "consumer amounts of RAM" are often run with what you might call "consumer amounts of sysadmin knowledge" and not notice the errors.

One time I took a working workstation from my home to my parents' home to give them. When I booted it up it gave a lot of strange kernel errors which I googled and discovered were reports of ECC correction. I reseated all DIMMs and it was fine. If that gave errors a few times a year instead of thousands of times on the first boot I wouldn't have noticed.

Sometimes I get a few per day. I only know that because my Linux kernel configuration happens to have whatever settings enabled to get them reported in dmesg.

...No? Faulty storage will almost always show up as I/O errors, modern storage generally doesn't want to send a block of data to the CPU if there is an error in it. If your bits are flipping, chances are it's RAM and not storage. Your storage already has ECC.

Some crappy flash drives might not do this, though. Seems to behave like a floppy disk at times.

The majority of storage errors I've seen since using BTRFS and ZFS everywhere have shown up only as the storage returning corrupt data and claiming it to be good. I've seen drives and SSDs return dozens of errors per month for months on end without any SAS or SATA errors or any SMART errors.

I've seen this in DC grade SSDs, NAS grade hard drives, and SSDs sold in high end laptops.

This can happen, after all HDD firmware and the link is not flawless. But have you actually ruled out RAM/CPU as the primary cause? I'm skeptical.

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