Hi, all
I want to know the principle of the vxlan checksum offload NIC. I know the vxlan packet is composed of outer udp header, vxlan header and innel l2 frame. And I read one description of a vxlan checksum offload NIC: VXLAN overlay performance challenge: Hypervisor IP stack and standard NICs are not aware of the client TCP/IP traffic. The common offload hardware techniques such as: TCP segmentation/re-assembly RX/TX checksum offload CPU core scaling (RSS/TSS) do not operate on the VM TCP/IP packets (inner payload) which leads to significant CPU overhead and much lower performance. Mellanox ConnectX-3 Pro adapter card offloads those tasks to the hardware leading to significant CPU overhead reduction and greater performance. I think the ip checksum and tcp/udp transport checksum of inner payload is calculcated by vm itself, so why it is needed to be calculcated in physical NIC? Looking forward for your reply. Thanks. _______________________________________________ dev mailing list dev@openvswitch.org http://openvswitch.org/mailman/listinfo/dev
