4 Replies Latest reply on Jan 20, 2015 1:17 PM by Colargol59

    Dual port 10Gbe performing at half speed


      I have two servers running OpenSUSE both with  Intel dual port 82599EB 10-Gigabit SFI/SFP+ using the ixgbe drivers. And I'm not getting the bandwidth I expect with iperf. Both ports are connected directly to the the other two ports of the second server.


      On one machine I run


      iperf -s


      On the other machine I run these two commands in separate terminals.


      iperf -c -t 20 -B

      iperf -c -t 20 -B


      And I get


      [  4]  0.0-20.0 sec  7.63 GBytes  3.28 Gbits/sec

      [  5]  0.0-20.0 sec  14.7 GBytes  6.30 Gbits/sec


      If I run only one port, I get


      [  6]  0.0-20.0 sec  22.8 GBytes  9.80 Gbits/sec


      Shouldn't I be able to expect roughly 10Gbe on each port simultaneously? Do I have the wrong hardware for that requirement? Or an invalid test?