poor network performance when using X520-DA2

[SRind]

I´ve got a problem with a server connection using the following combination:

IBM Server SystemX 3450 Typ:7379-K4G (PCIE x8 slot, 25w), running Windows Server2008R2

Intel Network Adapter X520-DA2

Intel TwinAxial Cable 3m (XDACBL3M)

D-Link switch DGS-1510-52

Problem:

10Gbit Link is up, but the performance is like 10Mbit. Gigabit connection with the internal adapter is much faster!

Even when i try to open the management gui of the adapter it takes several seconds to open and everything seems to be very slow.

As i don´t use them i tried to disable the IPv6 but this didn´t have any effect.

Any ideas?

Thank you in advance! :-)

best regards

Stefan Rindler

[st4]

Hi Stefan,

Thank you for the post. Please provide additional info:

1) What is the driver version?

2) Have you check if there is any configuration on the swtich that needs to be ajusted?

3) Have you installing the NIC in another system to test?

rgds,

wb

[SRind]

Hi wb, thank you for answering.

The driver is 11.07.2014 version 3.9.58.9101.

As far as i know, the switch should need no further configuration at this point. I use them in several environments and i asked the D-Link guys in advance - they said the constallation with the twin axial cable should work fine.

The problem is, that the Server is a client system in productive use, so that i can´t work on it while people work there. I could take the adapter out and try it in another system. If there will be no other solution, i will do that the next step.

[SRind]

maybee i found the problem in the whitepapers of the server: I found out, that the PCIE slot i used is x8 but only x4 wired. I will try the adapter with another slot which is fully wired. If this fixes the problem i will mark the thread as solved :-)

Hope i can go there and try it this week.

[st4]

Hi Stefan,

Thank you for the update. Please do let me know the result.

rgds,

wb

[SRind]

I have been there two day´s ago. I tried the Adapter in another Slot (8x - fully wired) then in a 16x - no change. I´ve got connection, 10GBit link is up, but slow as 10Mbit. I tried every option that the driver has like switching off the flow control, no jumbo frames etc...

I finally took the nic out now and hope that i soon can find some time and possibility to try it in another system and sceario.

[SRind]

It´s still not solved yet. After a few more tests we figured out, that the upstream speed seems to be o.k., just the downstream is so low. We also figured out, that the quality of the connection changes, when we changed the direction of the cable. This should make no difference but it does!

I ordered a new cable which we try today. We also try an alternative switch.... we will see.

[SRind]

Looks like the problem is solved. I changed the (brandnew) switch. That brought the success. Obviously it had a problem with the SFP+ Ports. So there was never really a problem with the intel devices. Once more one thing i learned: If there is any problem with hardware - check all the other brands first! ;-)

Thank you for your affords!

rgds

Stefan

[rhou2]

I see similar problem, I use UDP protocol, the throughput only 2Gbps.