How many megabytes per second may I expect from a gigabit USB 2.0 network card under linux?

4

I'm interested in the actual real-word throughput attainable with an external 1000BaseT USB 2.0 network card under Linux. I have been able to attain 90 megabytes per second on a PCI-E interface, but the USB 2.0 bus has a theoretical limit of 480Mbit/s, and in practice less than 40 megabytes per second.

Is the actual throughput attainable with such a card under linux 40, 30, 20, or even as low as 10 megabytes per second, eg. no better than a normal 100BaseT network card?

Nakedible

Posted 2010-04-02T09:55:15.417

Reputation: 461

1i'd expect your throughput will bottleneck at the USB bus, so you'll never even approach practical Gig-E limitations. – quack quixote – 2010-04-02T11:38:25.310

1Thanks, I am aware of that. The question is how fast will it go - it's clear that the performance is at most something like 30%-40% of Gig-E, but it is important for me to know how much less. – Nakedible – 2010-04-02T12:17:10.240

Answers

3

Bought an USB gigabit ethernet adapter. This one is from A-Link and uses the 'asix' kernel driver. Throughput is a stable 37-38 megabytes per second.

That's more than what I was guessing it to transfer. Basically that means that it can saturate most less than a gigabyte links, such as 300 Mbit wireless N and a 200 MBit broadband that's available around here.

Nakedible

Posted 2010-04-02T09:55:15.417

Reputation: 461