Hardware/Driver Tuning Required

If a CPU core is fully utilized by interrupts, the network card driver may need tuning. Some cards, such as igb, are able to use more queues for processing packets which will spread the load across multiple cores and result in higher throughput, but not every workload is helped by these options, so less queues may also help. Another item to check is under System > Advanced on the Networking tab. Ensure that the boxes are checked for Disable hardware TCP segmentation offload and Disable hardware large receive offload. If they are already checked, try toggling Disable hardware checksum offload. If no difference is observed, toggle it back