How to achieve maximun throughput in PCIe?

Hi,

We are transferring video frames from Jetson AGX Xavier PCI Endpoint to Jetson AGX Xavier PCI Root complex. The throughput which we achieved is given below,

| PCI gen | Observed fps | Max Bandwidth | Observed Bandwidth |

| PCIe 1.0 | 2660 fps | 2 GB/s | 1.52 GB/s |

| PCIe 2.0 | 5000 fps | 4 GB/s | 2.86 GB/s |

| PCIe 3.0 | 9200 fps | 8 GB/s | 5.2 GB/s |

| PCIe 4.0 | 15600 fps | 16 GB/s | 8.92 GB/s |

We found the frame-rate at which the video frames are being received in Root complex using gstreamer application with sink as fakesink. We used 8 lanes to transfer the video frames. We calculated the throughput from the fps we have received. In the above table, the difference between max bandwidth and observed bandwidth in PCIe gen 3.0 and PCIe gen 4.0 is high. How can we improve the throughput?