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Comment by diggan | Hacker News Reader

> and fewer disparate materials (no moving parts = no coils,bearings,motors...)

But even so, isn't the lifetime of a SSD less than a HDD given the same amount of writes? Especially when you try to have the same amount of storage available.

So say I want 16TB, I can either get 1 16TB SATA drive, or something like 4 4TB SSDs (or 8 2TB) to have the same storage, is the physical volume still less in that case? And, if I write 16TB of data each month to each of these alternatives, which one breaks first and has to be replaced?

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A typical consumer hard drive is going to last about 5 years, maybe more but it will wear just from existing. If you wrote 16GB to it a month that wont be a challenge for it.

The SSD however will be specified on a life of how many writes it can do. For example a 990 Pro from Samsung will have a specified life of 1200TB. That is about 76,800 months of operation at 16GB, this is not only not a challenging workload for an SSD but you have 8 of them so 8 * 76800 months of operation on average.

I have SSDs that are quite old, my original Intel 80GB G1 still works and still has 80% of its life left but its utterly obsolete as its too small to be useful and 500MB/s on SATA is a bit dated. All the OCZ SSDs are dead long ago but the Crucial M4 is still trucking along and its 512GB so still useful enough as is the Western Digital 1TB. I have barely scratched the surface of their usage life despite writing 35TB on them they still have 95% life over 42,000 hours of operation.

So at 16GB writes monthly they are going to last as long as the silicon and PCB lasts, which if made well could be decades. They will certainly become obsolete in speed and size more than likely rather than dying.

> I have barely scratched the surface of their usage life despite writing 35TB on them they still have 95% life over 42,000 hours of operation.

What are you using these drives for, if I may ask? It seems to barely be used for anything, or I'm an outlier here. Here's an example of my main drive in my desktop/work computer:

    Model: Samsung SSD 980 PRO 2TB
    Power On Hours: 6,286
    Data Written: 117,916,388 [60.3 TB]

I'm just an average developer (I think), although I do bounce around a lot between languages/projects/manage VMs and whatnot, and some languages (Rust) tend to write a lot of data to disk when compiling.

But the ratio difference seems absurd, you have ~0.0008 written per hour, while I have ~0.0096, that's a huge difference.

Here's what I ran to get the data, in case others wanna check theirs: https://gist.github.com/victorb/f120f5b9bcc1c04a4c3d0107f633...

Both of these are games, so they tend to sit with contents for longer. My boot SSD is 31TB in 6183 hours so quite a bit faster usage than those old drive but about half your rate. Its very workload dependent how long SSDs last. 16GB a month is extremely slow, much slower than my usage at 120GB a day. SSDs you could write their entire contents every day and they would still be working 5 years later but probably not 10.

My main OS disk (256 GB SATA) reports 40k power on hours and 27.5 TBW. I've also got a 4 TB nvme drive that's at 16.5k power on hours and 5.7 TBW and an 8 TB SATA drive that's at 18.5k hours and 25 TBW.

A server machine with multiple busy databases has 24.6 TiB written in 1349 hours. That’s on ZFS. As such, I’d say your usage patterns appear rather non-average.

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