I was setting up a PCIe Interface Communication using Non-Transparent Bridging on a DriveAGX Pegasus running Drive9 according to the guide at https://docs.nvidia.com/drive/drive_os_188.8.131.52L/nvvib_docs/index.html#page/DRIVE_OS_Linux_SDK_Development_Guide/System%20Programming/sys_components_non_transparent_bridging.html# to have a fast interconnect between XavierA and XavierB.
From what I could see, the PCIe switch did have the correct configuration (usecase4.0) and an appropriate firmware (IMG version 1.08 BD58) already installed.
The connection works, but is very slow. I used the tool iperf to benchmark the connection and it did report a speed of about 380Mbit/s. I would have expected a much higher speed.
iperf reports 940Mbit/s for the 1GbE connection over the internal Ethernet switch and about 6000Mbit/s for the external 10GbE connectors when sending data between XavierA and XavierB. These numbers seem legit do me, so it seems the benchmarking tool does its job.
Do others also see a low speed on the PCIe Interface Communication too or are there some settings that can increase the speed?