Well, it shouldn't be slower than "Read 1,000,000 bytes sequentially from memory" (741ns) which in turn shouldn't be slower than "Read 1,000,000 bytes sequentially from disk" (359 us).

That said, all those numbers feel a bit off by 1.5-2 orders of magnitude -- that disk read speed translates to about 3 GB/s which is well outside the range of what HDDs can achieve.

https://brenocon.com/dean_perf.html indicates the original set of numbers were more like 10us, 250us, and 30ms.

And it links to https://github.com/colin-scott/interactive_latencies which seems like it extrapolates progress from 14 years ago:

        // NIC bandwidth doubles every 2 years
        // [source: http://ampcamp.berkeley.edu/wp-content/uploads/2012/06/Ion-stoica-amp-camp-21012-warehouse-scale-computing-intro-final.pdf]
        // TODO: should really be a step function
        // 1Gb/s = 125MB/s = 125*10^6 B/s in 2003

which means that in 2026 we'll have seen 11 doublings since gigabit speeds in 2003, so we'll all have > terabit speeds available to us.

▲ amluto 4 hours ago | parent | next [-]

> that disk read speed translates to about 3 GB/s which is well outside the range of what HDDs can achieve.

That’s PCIe 3.0 x4 or PCIe 4.0 x2, which a decent commodity M.2 NVMe SSD can use and can possibly saturate, at least for reads.

> which means that in 2026 we'll have seen 11 doublings since gigabit speeds in 2003, so we'll all have > terabit speeds available to us.

We’re not that far off. 100GbE hardware is not especially expensive these days. Little “AI” boxes with 400-800 Gbps of connectivity are a thing.

That being said, all the connections over 100Gbps are currently multi-lane AFAIK, and the heroic efforts and multiplexing needed to exceed 100Gbps at any distance are a bit in excess of the very simple technology that got us to 100Mbps “fast Ethernet”.

	▲	vitus an hour ago \| parent [-]
		> That’s PCIe 3.0 x4 or PCIe 4.0 x2, which a decent commodity M.2 NVMe SSD can use and can possibly saturate, at least for reads. Given that there's a separate item for sequential disk reads vs SSD reads, I think it's pretty clear that particular item meant hard drives specifically. Agreed that modern SSDs should be able to pull that off. > That being said, all the connections over 100Gbps are currently multi-lane AFAIK, and the heroic efforts and multiplexing needed to exceed 100Gbps at any distance are a bit in excess of the very simple technology that got us to 100Mbps “fast Ethernet”. Yeah. Terabit networking is not here yet, and it's certainly not "commodity network"-grade. We can LACP a bunch of 100G optics together, but we're probably 5-10 years out for 800G ethernet to become widely adopted and for 1600G to even be developed.

▲ yomismoaqui 4 hours ago | parent | prev [-]

You are right, but my comment was about a trivial observation: 1 green square is 10µs so half a green square should be 5µs (not 5ns)

So I guess it's a typo but it makes me doubt the other numbers.