Iperf3 PCIe NTB Non-crosslink bandwidth measurement

Please provide the following info (check/uncheck the boxes after creating this topic):
Software Version
DRIVE OS Linux 5.2.6
DRIVE OS Linux 5.2.0
DRIVE OS Linux 5.2.0 and DriveWorks 3.5
NVIDIA DRIVE™ Software 10.0 (Linux)
NVIDIA DRIVE™ Software 9.0 (Linux)
other DRIVE OS version
other

Target Operating System
Linux
QNX
other

Hardware Platform
NVIDIA DRIVE™ AGX Xavier DevKit (E3550)
NVIDIA DRIVE™ AGX Pegasus DevKit (E3550)
other

SDK Manager Version
1.6.0.8170
other

Host Machine Version
native Ubuntu 18.04
other

Hello, I followed the steps in Non-Transparent Bridging and PCIe Interface Communication and I have two Xavier devices communicating through each other using a PCIe ntb non-crosslink communication.
When trying to measure the bandwidth using iperf3, I get the following figures:

nvidia@xavier1a:~/workspace$ iperf3 -u -c 192.168.1.11 -b 100G
Connecting to host 192.168.1.11, port 5201
[  4] local 192.168.1.12 port 60717 connected to 192.168.1.11 port 5201
[ ID] Interval           Transfer     Bandwidth       Total Datagrams
[  4]   0.00-1.00   sec   210 MBytes  1.76 Gbits/sec  26837  
[  4]   1.00-2.00   sec   210 MBytes  1.76 Gbits/sec  26913  
[  4]   2.00-3.00   sec   211 MBytes  1.77 Gbits/sec  26996  
[  4]   3.00-4.00   sec   211 MBytes  1.77 Gbits/sec  27036  
[  4]   4.00-5.00   sec   211 MBytes  1.77 Gbits/sec  27027  
[  4]   5.00-6.00   sec   212 MBytes  1.77 Gbits/sec  27072  
[  4]   6.00-7.00   sec   211 MBytes  1.77 Gbits/sec  27055  
[  4]   7.00-8.00   sec   211 MBytes  1.77 Gbits/sec  27001  
[  4]   8.00-9.00   sec   211 MBytes  1.77 Gbits/sec  27032  
[  4]   9.00-10.00  sec   211 MBytes  1.77 Gbits/sec  27010  
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bandwidth       Jitter    Lost/Total Datagrams
[  4]   0.00-10.00  sec  2.06 GBytes  1.77 Gbits/sec  0.011 ms  9011/269979 (3.3%)  
[  4] Sent 269979 datagrams

iperf Done.

The bandwidth of 1.77 Gbits/sec is not in line with the theoretical limit of a PCIe connection of 4 lanes.
How can we get a better performance out of the connection in order to get as close to the theoretical limit as possible?

Thanks in advance for your reply

Dear @erick.vieyra,
We will check internally and update you. Could you check the same with our latest release DRIVE OS 5.2.6? Also, check with iperf instead of iperf3 and share the results.

Thanks for your reply @SivaRamaKrishnaNV !
I have redone the tests using iperf and iperf3. There does not seem to be much difference. The results are shown below:

iperf XavierB Server, XavierA Client

nvidia@xavier1a:~$ iperf -c 192.168.1.12
------------------------------------------------------------
Client connecting to 192.168.1.12, TCP port 5001
TCP window size: 2.50 MByte (default)
------------------------------------------------------------
[  3] local 192.168.1.11 port 54554 connected with 192.168.1.12 port 5001
[ ID] Interval       Transfer     Bandwidth     
[  3]  0.0-10.0 sec  2.70 GBytes  2.32 Gbits/sec

iperf3 XavierB Server, XavierA Client

Connecting to host 192.168.1.12, port 5201
[  4] local 192.168.1.11 port 57544 connected to 192.168.1.12 port 5201
[ ID] Interval           Transfer     Bandwidth       Retr  Cwnd
[  4]   0.00-1.00   sec   274 MBytes  2.29 Gbits/sec    0    639 KBytes       
[  4]   1.00-2.00   sec   279 MBytes  2.34 Gbits/sec    0    639 KBytes       
[  4]   2.00-3.00   sec   279 MBytes  2.34 Gbits/sec    0    639 KBytes       
[  4]   3.00-4.00   sec   280 MBytes  2.34 Gbits/sec    0    639 KBytes       
[  4]   4.00-5.00   sec   279 MBytes  2.34 Gbits/sec    0    639 KBytes       
[  4]   5.00-6.00   sec   279 MBytes  2.34 Gbits/sec    0    639 KBytes       
[  4]   6.00-7.00   sec   280 MBytes  2.35 Gbits/sec    0    639 KBytes       
[  4]   7.00-8.00   sec   279 MBytes  2.34 Gbits/sec    0    639 KBytes       
[  4]   8.00-9.00   sec   280 MBytes  2.35 Gbits/sec    0    639 KBytes       
[  4]   9.00-10.00  sec   280 MBytes  2.35 Gbits/sec    0    639 KBytes       
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bandwidth       Retr
[  4]   0.00-10.00  sec  2.72 GBytes  2.34 Gbits/sec    0             sender  
[  4]   0.00-10.00  sec  2.72 GBytes  2.34 Gbits/sec                  receiver

iperf Done.