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Comment by mmmpetrichor | Hacker News Reader

If some typical write pattern from a typical app is wearing out the SSD really fast, I'd say that's the SSD firmware engineer's problem? And I think they've actually done a great job in general, judging by the typical lifespan of SSDs and the typically great performance. I'd argue that if the drive is designed correctly, most programmers shouldn't have to care about low level details. (I did say MOST).

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I think you misspelled "it's the user's problem". I don't think most companies care until it becomes something that materially affects them. Until then, users are reliant on the developers of the applications they use to make up for the deficiencies in lower layers.

A reputation for drives that fail faster than their competitors will definitely effect them!

> A reputation for drives that fail faster than their competitors

How can they get that if they stuff enough fake reviews, plus the legion of consumers who would have no idea that the drive was the issue and not "viruses".

Neither of those apply to enterprise customers.

That's a completely different market, to which are marketed different drives.

True mostly! OEMs are the largest non-enterprise market, and they do (roughly) the same types of testing and validation a enterprise customer would though.

No one is going to be selling a million laptops with a drive from RandoDriveManuGoodBrand off Amazon with no track record and no validation.

Anyone buying the non-name brand types of drives knows they're getting (at best) something that might only work a little while before exploding.

The name brands like Samsung, et. al. work hard to make their firmware not grenade something (and the drives overall to be AT LEAST as reliable as their competitors) BECAUSE they want the name to mean something. It is what drives customers their way, most of the time.

If they get a reputation as a company selling junk (cough Deskstar/Deathstar) that costs them billions over many years.

The firmware's job is wear leveling - making sure all the sectors wear out at about the same time, which they do a great job at. But SSDs can write so fast that you can burn out the drive in months (maybe even weeks?) if you wanted to. There's nothing the firmware can do fix the limitations of flash itself. The important thing to keep in mind is that for write heavy workloads, you need to keep write amplification in mind.

I remember an adjacent team to mine that had to store several gigs of data which changed often, but only a small percent changed at any one time. They needed to recover quickly from a crash so they wrote it to disk. But they wrote the entire data set out to disk after every update, instead of keeping it in e.g. rocksdb or even sqlite. Their entire fleet burnt through their SSDs at about the same rate, so machines were dying in rapid succession, ouch. Write amplification is a real problem, but SSDs great performance often masks it being an issue until down the road.

> But SSDs can write so fast that you can burn out the drive in months (maybe even weeks?)

You can burn out a modern consumer drive in 2 days if you want to. Write perf ~6 gb/s, mtbf 700 tb written on a 1 tb drive. The tlc/qlc cells have very poor endurance imo.

I am surprised the article doesn't mention monitoring TBW (TerraBytesWritten). I found it a good indicator for how much data is actually written to the SSD. In my case, I decided to buy cheap consumer SSDs (from WD), because I calculated I have only about 50TBW per year on my VM-drive, a ZFS-Mirror. In reality, it is even less - so far 14TBW in 2022, with 16 VMs. See a blog post here for how I monitor the stats in InfluxDB [1]. WD says the drive has an average lifetime of about 300 to 400 TBW, so I can expect at least another 5 years.

[1]: https://du.nkel.dev/blog/2021-05-05_proxmox_influxdb/#config...

"Storage study finds SSDs might not be much more reliable than HDDs after all"

https://www.pcgamer.com/storage-study-finds-ssds-might-not-b...

"Are SSDs Really More Reliable Than Hard Drives?"

https://www.backblaze.com/blog/are-ssds-really-more-reliable...

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