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New 10 GbE USB adapters are cooler, smaller, cheaper

jeffgeerling.com

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Re: New 10 GbE USB adapters are cooler, smaller, cheaper

#301

Post by jburgess777 »

ZekeSulastin wrote: post #261
Fnoord wrote: post #117

Earlier quoted context omitted.

DACs are very cheap (second hand and AliExpress) and they never use much W. If both machines are near each other though (which a DAC cable implies) and both run Linux and both support Thunderbolt, you might be better off with a direct ethernet over TB connection. Whether macOS supports such, I don't know. The other side will then also need a low power NIC (of which fiber and DAC over SFP+ are less power hungry). What…

I just wish someone would come out with a PCIE 4x1 capable card with SFP - my main desktop’s non-GPU expansion slots are all 4x1 electrically and even the one you linked is a 3x2. As far as I can tell the only 4x1 cards available are RTL8127 or AQC113 RJ45 ones :( I suppose an NVME riser is also an option, albeit janky.

There are RTL8127 cards with SFP+, e.g. https://www.lekuo.com/product_view.php?id=659

edit: on looking closer, that still seems to be an x4 card.

Re: New 10 GbE USB adapters are cooler, smaller, cheaper

#302

Post by iknowstuff »

stonegray wrote: post #299
fulafel wrote: post #258

Earlier quoted context omitted.

A single threaded benchmark better represents real performance, I'd argue. 10 Gbps is only 1.2 GB/s after all and few applications use parallel streams.

I think the intention is to measure the adapter itself independent from the CPU/overall system. Besides, I can’t think of a typical single threaded application that would use those data rates, can you?

Steam downloads

Re: New 10 GbE USB adapters are cooler, smaller, cheaper

#303

Post by lpcvoid »

Someone1234 wrote: post #151
TomatoCo wrote: post #141

Earlier quoted context omitted.

Going by Fabien Sanglard's cheat sheet (who I trust uncritically) https://fabiensanglard.net/usbcheat/index.html it looks like 3.2 actually is a broader term than expected. Maybe there was some awful attempt at backwards compatibility? Or forwards?

Great site, thanks for the link. But holy heck, that "Also Known As" column is complete chaos. What the heck is wrong with the USB Consortium, do they have brain damage? Also, according to that table, "USB4 Gen 2×2" is a downgrade on "USB 3.2 Gen 2x2", since the cable length is 0.8m instead of 1m for the same speeds. Which is uhh unexpected.

I really, really wish somebody would explain to me what thr USB consortium was smoking, yeah. I cannot explain it.

Re: New 10 GbE USB adapters are cooler, smaller, cheaper

#304

Post by stonegray »

iknowstuff wrote: post #302
stonegray wrote: post #299

Earlier quoted context omitted.

I think the intention is to measure the adapter itself independent from the CPU/overall system. Besides, I can’t think of a typical single threaded application that would use those data rates, can you?

Steam downloads

Steam download rates are throttled based on how fast it can actually install the game so it’s a bit of an outlier

Re: New 10 GbE USB adapters are cooler, smaller, cheaper

#305

Post by [deleted] »

exabrial wrote: post #225

Jeff: I see a possible problem with your tests that bit me before! ipferf3 is not multithreaded by default. The more capable computers probably have an interrupt rate sufficient to handle 10gig over USB (which likely multiplies the interrupt rate needed), but it's completely possible you're pushing the interrupt rate limits on the Macbook Neo and other lower powered hardware. Any chance you could re-run with `-P 4` w…

[deleted]

Re: New 10 GbE USB adapters are cooler, smaller, cheaper

#306

Post by dgacmu »

exabrial wrote: post #225

Jeff: I see a possible problem with your tests that bit me before! ipferf3 is not multithreaded by default. The more capable computers probably have an interrupt rate sufficient to handle 10gig over USB (which likely multiplies the interrupt rate needed), but it's completely possible you're pushing the interrupt rate limits on the Macbook Neo and other lower powered hardware. Any chance you could re-run with `-P 4` w…

Most modern ethernet chips, including those used on USB ethernet devices, have adaptive interrupt coalescing (or moderation) for network I/O, which renders this likely not as big a deal as it once was. There will still be limits on packets/sec/core but it's not because of interrupts.

Re: New 10 GbE USB adapters are cooler, smaller, cheaper

#307

Post by MisterTea »

donatj wrote: post #161
MisterTea wrote: post #134

Earlier quoted context omitted.

10 Gb is cheap! Mikrotik has a 4x10Gb + 1x1Gb port switch for $150 USD and an 8x10Gb version for about $275. I have the 8 port version. SFP+'s and fiber are cheap, like maybe 50 bucks for the SFP+ set and fiber. 10Gb PCIe cards are maybe ~$50 new on Amazon with Intel chips and cheaper on eBay - I bought used 10 Gb Mellanox cards for $25 each - "they just work" under FreeBSD and Linux. Copper 10 Gb used to consume waa…

I redid the backbone of my home in 10Gb fiber, and "cheap" is not the term I would use. Especially when you can get perfectly cromulent 1GbE switches for like $10 these days. The Mikrotik switches [1] work technically speaking but they are quite difficult to configure. You have to pull them from your network, connect physically to a specific port, force your machine onto a specific IP, connect to a specific IP. I cou…

I don't configure anything on the mikrotik. Out of the box it's a dumb switch and that is all I want.

> The Mikrotik switches are also fanless, and 10GbE SFP+ adapters throw off a lot of heat.

If you are talking about copper SFP's, then that's the problem: copper. It takes a lot of energy to drive a wire at GHz speeds, not so much with an optical link (though it's getting much better.) I have only ever felt luke warm optical and DAC SFP's. Copper 10 Gb SFP's are burning hot. I avoid using copper and run fiber.

Re: New 10 GbE USB adapters are cooler, smaller, cheaper

#308

Post by marcosdumay »

eqvinox wrote: post #67
_blk wrote: post #42

Earlier quoted context omitted.

The issue might not be the wattage bit rather the minimum voltage. (Some?) Macs seems to charge at 15v already, most laptops need 20v

Coincidentally, the USB-C spec is written such that wattage implies a minimum set of supported voltages: * ≤15W charger: must have 5V * ≤27W charger: must have 5V & 9V * ≤45W charger: must have 5V & 9V & 15V * (OT but worth noting: >60W: requires "chipped" cable.) * ≤100W charger: must have 5V & 9V & 15V & 20V (levels above this starting to become relevant for the new 240W stuff) (36W/12V doesn't exist anymore in PD…

It's a 3A supply up to the 100W one, that gets upped to 5A at higher voltages.

Varying voltage power supplies are usually capped by current, not power. That's because many of the components, set maximum current and voltage that you must obey independently.

At higher voltages people start accepting higher loses in stuff like cables, because fire-safety becomes a more important concern than efficiency. So the standard relaxes things a little bit.

Re: New 10 GbE USB adapters are cooler, smaller, cheaper

#309

Post by cyberax »

One another thing to try: set the MTU to 9000. But don't do this on your main interface, or you'll get haunted by traffic being blackholed.

At home, I have separate VLANs for the 9k packets. It has a separate subnet (both V6 and V4), so it works perfectly. The devices on this VLAN use it directly if they can, and everything else goes through the router that sends proper ICMP "too big" messages.

Re: New 10 GbE USB adapters are cooler, smaller, cheaper

#310

Post by toast0 »

bri3d wrote: post #200

I'm disappointed that both the article and comments don't go into the actual differences between how these adapters work and the overhead incurred by USB. At a high level, I'm pretty sure Thunderbolt will be significantly better in all situations: Thunderbolt is PCIe; depending on the way the network card driver works, the PCIe controller will usually end up doing DMA straight into the buffers the SKB points to, and…

> At a high level, I'm pretty sure Thunderbolt will be significantly better in all situations:

None of my devices support thunderbolt; so not all situations.

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