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Comment by the_gorilla | Hacker News Reader

We don't really have to guess. Backblaze posted their stats for 4 TB HGST drives for 2024, and of their 10,000 drives, 5 failed. If OP's 2014 4 TB HGST drives are anything like this, then this is just snake oil and magic rituals and it doesn't really matter what you do.

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> If OP's 2014 4 TB HGST drives are anything like this, then this is just snake oil and magic rituals and it doesn't really matter what you do.

It might matter what you do, but we only have public data for people in datacenters. Not a whole lot of people with 10,000 drives are going to have them mostly turned off, and none of them shared their data.

5 drives failed in Q1 2024. 8 died in Q2. That is still a very low failure rate.

Drives have a bathtub curve, but if you want you can be conservative and estimate first year failure rates throughout. So that's p=5/10000 for drive failure. So chance of no-failure per year (because of our assumption) is 1-p. So, chance of no-failure per ten year is (1-p)^10 or about 99.5%

Is that for one drive, or for all 24 drives to survive 10 years?

That's for one drive. For all 24 it's about 88.7%.

Those are different drives though, they're MegaScale DC 4000 while OP is using 4 TB Deskstars. Not sure if they're basically the same (probably). I've also had a bunch of these 4TB Megascale drives and absolutely no problems whatsoever in about 10 years as well. Run very cool as well (I think they're 5400 rpm not 7200 rpm).

The main issue with drives like these is that 4 TB is just so little storage compared to 16-20 TB class drives, it kinda gets hard to justify the backplane slot.

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