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[Reformed]

Pretty sure a cable run is hardware, Sir. Ethernet doesn't rate adapt once connected so no point in measuring throughput between two devices directly connected to the cable run: you look at speed, duplex and errors and get that from switches.

An error free, stable cable run at 10G will give 10G as long as the equipment either side isn't a bottleneck. Software can't measure the performance of the cable run as it has to run on a computer. You're measuring performance from one computer to another via all the equipment and software layers in between, not the cable run.

Switches that are non-blocking and the error rates either side are fine. If they're very low or zero and the link is stable the throughput on the cable is what the link says on the tin.

[Ronski]

Whatever, sir, we're both guessing at what Skieci meant until they come back and clarify. Yes you are correct cables are hardware, but he still asked if there was any software that can test through put 

[skyeci]

Thanks for the comments. As I don't have access to a certified tester like a fluke or something I just wondered if it was possible to see if my cabling was any good using some software  to test its performance...

[Reformed]

Sadly no. Any software checker will be restricted by the hardware either side and will never give a result higher than the maximum the hardware will support.

To check if a cable can support x Gbps you need hardware either side that can actually push that many Gbps through the cable.

[Weaver]

I would think that without special kit then UDP ramping up to flat out transmission rate would be the best you can do on the cheap. Of course a tester that could inject arbitrary waveforms would be far better, far more stressful, but perhaps not sufficiently ‘relevant’ to your everyday world - what’s the word I need here?

[burakkucat]

- what’s the word I need here?

"usage". 

[Alex Atkin UK]

I would think that without special kit then UDP ramping up to flat out transmission rate would be the best you can do on the cheap.

You'd need to compare it to a bad cable though, as even over fibre I get "some" retries from TCP traffic if I try to max out the link with perf3 so I'd expect UDP to always show some dropped traffic.  There's just so many places things can go wrong in the software stack that it makes knowing what is normal and what is a defect really tricky.

The best you can do really is bring up the interface statistics and look if there have been any dropped packets, collisions or overruns.  But again, I see dropped packets even on 10Gbit when stress testing. (or maybe I DO have a fault?)

[Ronski]

Thanks for the comments. As I don't have access to a certified tester like a fluke or something I just wondered if it was possible to see if my cabling was any good using some software  to test its performance...

Can you clarify whether you want to know the maximum speed your cable will support, or that it will work fine at 1,2.5,5, or 10Gbps?

[Reformed]

The best you can do really is bring up the interface statistics and look if there have been any dropped packets, collisions or overruns.  But again, I see dropped packets even on 10Gbit when stress testing. (or maybe I DO have a fault?)

Overruns are between kernel and NIC, collisions can't happen on full duplex connections. Drops it depends which they are however filling a link you will see drops when you actually fill it. Have to go above the link's capacity to find that capacity with software.

[Reformed]

Thanks for the comments. As I don't have access to a certified tester like a fluke or something I just wondered if it was possible to see if my cabling was any good using some software  to test its performance...

You are going to need hardware, but what's your budget?

Mikrotik have some good kit, Zyxel have a switch that might be perfect. You'll likely only need a couple of ports capable of more than 1G on each switch so there are options.

[Alex Atkin UK]

Overruns are between kernel and NIC, collisions can't happen on full duplex connections. Drops it depends which they are however filling a link you will see drops when you actually fill it. Have to go above the link's capacity to find that capacity with software.

Thanks, I was hoping someone would clarify what they mean as its something I've never really thought much about since the 10BASE2 days.  It just struck me as odd as I never saw drops on Gigabit but have since being on 10Gbit.