[menaerus]

> I get ~30 GiB/s for threaded sequential memory reads, but ~4 GiB/s for SSD. However, I think the SSD number is single-threaded and not even with io_uring—so I need to regenerate those numbers. It's possible it could be 2-4x better.

Assuming that you run the experiments on NVMe SSD which is attached to PCIe 3.0, where theoretical maximum is around 1GB/s per each lane, I am not sure I understand how do you expect to go faster than 4 GiB/s? Isn't that already a theoretical maximum of what you can achieve?

[formerly_proven]

PCIe 4.0 SSDs are pretty common nowadays and are basically limited to what PCIe 4.0 x4 can do (around 7 GB/s net throughput).

[menaerus]

I don't think they're that common. You would have to have quite recentish motherboard and CPU that both support PCIe 4.0.

And I'm pretty sure that parent comment doesn't own such a machine because otherwise I'd expect 7-8GB/s figure to be reported in the first place.

[dagmx]

I really doubt they’re that common. They only became available on motherboards fairly recently, and are quite expensive.

I’d guess that they’re a small minority of devices at the moment.

[robocat]

PCIe 5.0 has just recently started showing up on consumer motherboards.

4.0 might not be common, but surprisingly it is now the previous generation!

[Sirupsen]

You might be very right about that! It's been a while since I did the SSD benchmarks. Glad to hear it's most likely entirely accurate at 4 GiB/s then!