A switch with just 49 ns latency? What strange magic is this?

Australian company Exablaze has released a switch with claimed latency of just 49 nanoseconds. The ExaLINK Fusion FastMux is designed for those who can't wait for data to make it through a box, especially high-frequency traders but also HPC types. The device isn't a switch to rank with the likes of Cisco or Arista, because it …

[David Austin]

I Know it's completely pointless...

But the Primal part of my brain is screaming to buy one to squeeze that little extra bit of "git gud" performance out of OverWatch.

[jake]

But it's not a switch.

It's a multiplexer.

Comparing it to a switch is like comparing pears & apples.

[tedleaf]

Re: But it's not a switch.

https://www.theregister.co.uk/2017/04/27/apple_lawyers/

That's never stopped people from doing so..

[jasonmac404]

Re: But it's not a switch.

That's only partially true. Firstly according to the website, it's also a pretty quick L2 switch, but more importantly, it's used in places where people would usually use a switch (like the Mellanox example in the article) so it might not be a switch, but it competes against them.

[John Smith 19]

"It's a multiplexer."

Absolutely.

My understanding of a true switch is it's an N-N device. Any I/P to any O/P. This a 1:N or N:1 device

A very radical loss in flexibility.

If it's targeted at HFT's I'm sure it will be "reassuringly expensive" to coin a phrase but for the rest of us?

[Richard 12]

Sounds like a hub to me

Doesn't a switch, well, switch?

[tedleaf]

I've got a nice big chunk of copper than can do the same thing,even quicker,it's yours for £25.000.

[Kevin McMurtrie]

Product page says it has 49ns uplink latency as a 1Gbps to 10Gbps mux.

If I'm doing math right, a sensibly sized packet takes 12176 ns to arrive and 1217.6 ns to exit. That means the head of the packet must be delayed by at least 10958.4 ns to prevent a buffer under-run. It seems that the timing is for either a very small packet or it's measuring latency of the last bit in the packet. Each packet queuing to prevent a collision would also add another 1218 ns of latency.

Either way, it's after midnight and I shouldn't be attempting math.

[jasonmac404]

Jason Mac

I think you're doing the math wrong. It's a cut through device doing 10G/10G multiplexing. So the timing is presumably from the first bit, to the first bit where there is no queuing.

[SirWired 1]

Cut-through routing (where you don't wait for the whole thing to arrive before transmitting) has been used in switch products for years.

[Christian Berger]

"Cut-through routing (where you don't wait for the whole thing to arrive before transmitting) has been used in switch products for years."

Absolutely, and in the 10 Mbps era that was rather popular even, as there latency was more of an issue. Though I don't think most switches today will do it. Unless you are doing high speed trading, latency usually isn't that much of an issue.

[jasonmac404]

AFAIK, all modern 10G switches support cut-through, though none have latencies anywhere near this (special purpose) device.

[a pressbutton]

Re: The future...

In the context of HFT, the idea is to get the order to the exchange fastest.

If you shave 300-49 ns off the time (~250ns), super.

However, if you move your box just ~250 feet closer to the exchange, that will cancel the performance gain.

[Allan George Dyer]

Re: The future...

HFT shows that the financial system is broken and working against the needs of Society. If the financial system was an audio amplifier, then HFT would be ultrasonic ringing, and the designer would insert a low-pass filter to improve the amplifier's performance. Instead, the HFT traders throw money at increasing the problem, because it makes them more money.

[Charles 9]

Re: The future...

"HFT shows that the financial system is broken and working against the needs of Society. If the financial system was an audio amplifier, then HFT would be ultrasonic ringing, and the designer would insert a low-pass filter to improve the amplifier's performance. Instead, the HFT traders throw money at increasing the problem, because it makes them more money."

Your analogy is broken here because the HFT people WANT the ultrasonic ringing, as it gives them a money edge. That's why they're willing to throw money at it, because they get MORE money in return. It goes to basic human behavior, so you likely can't fix something like this without fixing the human being.

[inmypjs]

Re: The future...

"HFT shows that the financial system is broken"

Broken? More like being abused. The trading systems should add up to 5 seconds of random delay to each trade to stop traders wasting money on technology and location trying to screw each other.

[dlc.usa]

Re: The future...

"The trading systems should add up to 5 seconds of random delay to each trade to stop traders wasting money on technology and location trying to screw each other."

If the markets were truly free, yes, but that was the point regarding the broken financial system comment--markets are NOT free anymore, and no governments with the necessary jurisdiction are inclined to intervene. This is not a problem of technology, of course, but one of societal corruption.

[Charles 9]

Re: The future...

Then the traders will go back to the old method: bribery, as far up as needed.

[Anonymous Coward]

Re: The future...

"traders will go back to the old method: bribery, as far up as needed."

It's fairly clear from the limited evidence that's reached the UK public that bribery, insider trading, and other dubious practices have been generally acceptable to management in the City.

It's less obvious that behaviour like that will be quite so acceptable elsewhere in Europe, given the number of times that City companies have threatened to relocate elsewhere, and yet very few have done so in any meaningful way.

[Charles 9]

Re: The future...

But that was the FIRST thing they did. All the prime real estate's assumed to already be taken, including space WITHIN the exchange if at all possible. Now, due to the crazy demand, prime real estate commands prices too high for RoI to be worth it anymore. Which means time for Plan B: quicker turnaround at junction points because everything else is basically hampered by the speed of light in medium and the speed of electricity.

[katrinab]

Re: The future...

Your box is inside the exchange, and every machine is connected by the same length of cable regardless of what length is actually needed to reach it.

[phuzz]

For reference, in 49 nanoseconds light can travel about 15m, so you'll want to use cables that are as short as possible with this device, otherwise you're just wasting (nanoseconds of) your time.

[Timmay]

Gaming

The goddamn financial system. It's just gaming at its base level, albeit with actual money (well, virtual money but backed with other people's real money), and these gambling gimps just want the best gaming equipment they can buy to give them an edge over the competition.

They're not contributing to society, this is no use in the real world, this is all about 100% personal gain.

[Anonymous Coward]

Re: Gaming

Well, they are serving to push networking technology ahead...

[Anonymous Coward]

Re: Gaming

"Well, they are serving to push networking technology ahead..."

Not in any meaningful and generally applicable way they're not.

[John Smith 19]

You say HFT I say automated man-in-middle attack

Because that's what they do.

These people contribute no benefit to the financial system. They are well financed parasites who could not last a day if they actually "traded" in the real meaning of the term for any actual goal.

[Charles 9]

Re: You say HFT I say automated man-in-middle attack

You ever thought those parasites STARTED on the trading floor and simply found ways to get around them? It's like anything in human competition: anything for an edge, even if it means getting around the rules. If you think applying rules will change anything, you don't realize the lengths people will go when the stakes get that high.