The throughput of TCP traffic, greater than MTU size, exchanged between VMs using the OvS-DPDK datapath is significantly lower than the OvS Kernel datapath. This makes OvS-DPDK a less attractive choice for this type of use case, even though it is core for enabling NFV functions in domains that require higher throughput in TCP-based workloads, such as Telco's Service Providers.
This talk shows how TCP Segmentation Offload (TSO) is being enabled in the OvS-DPDK datapath in order to take advantage of NIC offload capabilities, to avoid segmentation inside the VM and, as a consequence, to scale the throughput in TCP-workloads between VMs. The considerations taken to achieve this will also be discussed during this talk.
Preliminary performance measurements show performance gains of 100x for traffic exchanged between VMs running on the same host and 10x for traffic exchanged between VMs running on different hosts, when compared to DPDK configurations without TSO support.
