For super large systems, you do something like DPDK or XDP instead for large memory and super high throughput, the kernel's network stack is not designed for th

For super large systems, you do something like DPDK or XDP instead for large memory and super high throughput, the kernel's network stack is not designed for that anyways. HPC has been moving huge data cross PCIe running Linux for a long while, there must be multiple ways to overcome IOVA-4GB-allocation limit. Last, they can be dealt with at hardware level, let the (smart) hardware(e.g. an offload engine, or accelerator) to manage the memory on its own for DMAs.