Evaluate OpenShift and OVN-Kubernetes with its primary network operating completely in userspace, covering physical NICs, containers, and virtual machines. Our previous PoCs FDP-198 and FDP-1285 already accomplished the first part:

• OVS bridges br-ex and br-int are of type netdev (userspace) rather than system (kernel),
• DPDK drivers (rather than kernel drivers) are used when attaching physical NICs to OVS bridges, and
• VDUSE devices (rather than VETH devices) are used to provide network connectivity aka eth0 in containers.

Now, develop a follow up PoC which, in addition, provides the following:

• vhost-vdpa devices (rather than tap devices) are used to provide network connectivity to KubeVirt virtual machines, and
• optimal CPU affinity and cgroup v2 cpuset settings for OVS and VDUSE.

Identify missing functionality and other shortcomings in OVS, DPDK, VDUSE and KubeVirt. The primary objective is to assess the feasibility, benefits, and costs of userspace networking in OpenShift as soon as possible. Submitting patches for upstream projects and reporting unrelated bugs are considered incidental.

Key results

• An OpenShift release image which allows to install a OpenShift cluster with OVS' userspace datapaths for the primary cluster network.
• A successful deployment of an OpenShift cluster which uses OVS' userspace datapaths for its primary network.
• Preliminary test results for OpenShift's conformance test suite run against a OpenShift cluster with OVS' userspace datapaths.
• Preliminary benchmark results for pod-to-pod-on-different-nodes scenario and vm-to-vm-on-different-nodes scenario on bare-metal.