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Comment by riku_iki | Hacker News Reader

What special about this SSD?

Check out the sequential 128k read at queue depth 16: https://images.anandtech.com/doci/16505/sr-s-sn850-1000.png

That's >2x higher throughput than an Optane at equivalent queue depth and (as far as I can see in the UK) at less than a tenth of the price: https://www.scan.co.uk/products/2tb-wd-black-sn850-m2-2280-p... vs https://www.scan.co.uk/products/15tb-intel-optane-dc-p4800x-...

And that's 7 GB/s from _one_ SSD. Aggregate memory bandwidth on something like the Zen3 is roughly 40 GB/s. These are also first generation PCIe 4, plenty more to come.

Doesn't require a huge improvement before you end up in a position where you simply don't have the memory bandwidth or cycles to deal with more than one drive.

I suspect the Optane wins most of the benchmarks because of it's outrageously good low queue depth random read performance - that's very effective for software that's not written for modern NVMe SSDs which benefit from very high queue depths. Check out the 4k random read performance from the SN850 at high queue depths:

https://images.anandtech.com/doci/16505/rr-s-sn850-1000.png

If you can keep the queues deep, it manages to beat the throughput of the Optane. You've got to design algorithms and data structures to exploit that kind of concurrency though.

This is the fastest consumer (flash) SSD.

a lot of M.2 2280 NVME SSD still being sold on the market are PCI-E 3.0. it is interesting to see its benchmarks against the samsung and other top tier competitors.

> a lot of M.2 2280 NVME SSD still being sold on the market are PCI-E 3.0.

That's true, but there are multiple PCI-E 4.0 available on the market for a year already, with benchmarks available too..

but look at the benchmarks for this drive versus the Samsung 980 Pro 1TB.

both are selling at $199 from newegg right now...

but the WD sn850 blows away the 980 pro in nearly every benchmark.

I still have a greater degree of trust in Samsung for reliability and greatly exceeding their specified write-endurances (torture tests of MLC samsungs from 3 years ago illustrate that for a desktop workstation, you would have to REALLY abuse them to ever run into the write endurance problem).

> but the WD sn850 blows away the 980 pro in nearly every benchmark.

I think they have some cache tuning differences, because while WD wins in many benchmarks by 30-40%, it losses the same 30-40% on long sequential writes.

I have no ssd expertise, so, can't comment why this could happen.

What I am really surprised by is the price of the enterprise ones (samsung PM1735, you can get a 3.2tb for like £600). Barely more expensive than consumers with massive performance (8GB/s read) and endurance. Not sure where is the catch.

The catch is that pricing and availability for grey-market enterprise drives is wildly inconsistent, and you often don't get a manufacturer's warranty. Also, enterprise drives don't use SLC write caching, so their peak write performance is usually substantially lower than on a consumer SSD. And not that it matters much for a desktop, but enterprise drives also don't do idle power management, so they stay pretty warm even when you're not using them.

It’s not just endurance. I wouldn’t use anything other than an older Samsung Pro (not an 850 Pro, before they went TLC), a Samsung Z, or an Intel Optane for something like a ZFS slog or a hardware RAID write accelerator cache - they have unmatched latency for these applications which cruet came by via their technical choices and is independent of write throughout.

Even with it's big performance gains, optane is still well ahead in almost every benchmark.

Shame more manufacturers don't make that type of drive

If the price point of the Optane is keeping consumers from embracing them, then why not look for another way to make something the consumers are willing to buy? That's kind of what WD does. They have a huge chunk of the consumer market.

> Shame more manufacturers don't make that type of drive

Now that Micron has apparently called it quits, it's a shame no manufacturers make that type of drive!

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