X550 and X710 Less than half speed on 10Gb Hyper-V Guests

[Keeop]

And back I come.........

Well, for ages I was enjoying around 9Gb speeds between VMs using my lovely quad port X710 daughterboard but on trying to get to the bottom of sub-par Internet speeds, I notice I am now only getting around 3.5Gb speeds between VMs again - same problem I was having with the X550 - please see https://community.intel.com/t5/Ethernet-Products/X550-T2-Less-than-half-speed-on-10Gb-Hyper-V-Guests/td-p/1567509. Arrgghhh!

So, any ideas as to what may be going on here? It was all OK so can only assume it is some Windows updates that have had a detrimental affect? Crazy stuff. The one physical port not assigned to Hyper-V works at full speed. If I iPerf from a VM to the host - i.e. Virtual NIC to Physical NIC - I get full speed. However, if I iPerf from Physical Host to VM I get around 3.5Gb, same if I do VM to VM.

Currently have SRV-IOV disabled and VMQ enabled and this was the same when I was getting full speeds throughout, so I haven't made any changes to the NIC settings at all.

I did try the good old X550 again as well, and get exactly the same results.

Any ideas please?

Cheers.

Keeop

[Akshaya1]

Hi Keeop,

Thank you for contacting Intel.

Apologies for the delay in the response. Kindly allow some time to review the details, and will get back to you with an update shortly.

We appreciate your patience.

Regards,
Akshaya 
Intel Customer Support Technician

[Keeop]

Hi,

Please feel free to close - I had reduced the memory assigned to a lot of my VMs and it was this that caused the throughput issues. Added additional memory and all VMs now running through these NICs at full speed.

Cheers.

Keeop

[Akshaya1]

Hi Keeop,

Thank you for the confirmation. I will proceed with closing the case now.

Feel free to reach out if you need any further assistance in the future.

Regards,
Akshaya 
Intel Customer Support Technician