10G NIC Speed issue

Hi,

Please help for improve performance of 10G NIC.

We have two 10G NIC "X540-T2 Intel network card with RJ45 copper Cat6A " .

One 10G NIC is installed on i5 with xenomai patched ubuntu OS.

And 2nd one is on i7 with xenomai patched ubuntu OS.

both card is connected back to back with crossover cable.

Ping is ruining ok.

We make test using i-perf utitlty for measure 10G nic performance but we get very less speed.

Results seems like as

iperf -c 192.168.10.6 -P 1 -i 1 -p 5001 -C -f g -t 10
------------------------------------------------------------
Client connecting to 192.168.10.6, TCP port 5001
TCP window size: 0.00 GByte (default)
------------------------------------------------------------
[  3] local 192.168.10.2 port 44870 connected with 192.168.10.6 port 5001
[ ID] Interval       Transfer     Bandwidth
[  3]  0.0- 1.0 sec  0.16 GBytes  1.36 Gbits/sec
[  3]  1.0- 2.0 sec  0.19 GBytes  1.66 Gbits/sec
[  3]  2.0- 3.0 sec  0.22 GBytes  1.85 Gbits/sec
[  3]  3.0- 4.0 sec  0.21 GBytes  1.80 Gbits/sec
[  3]  4.0- 5.0 sec  0.18 GBytes  1.50 Gbits/sec
[  3]  5.0- 6.0 sec  0.19 GBytes  1.63 Gbits/sec
[  3]  6.0- 7.0 sec  0.18 GBytes  1.54 Gbits/sec
[  3]  7.0- 8.0 sec  0.21 GBytes  1.80 Gbits/sec

Thanks,

-Ilesh