SRIOV scheduling with NIC capabilities

There is a per packet overhead associated with ethernet based packet processing, examples of this processing are packet checksum management, protocol segmentation and vlan offloads.

Modern network controllers (NIC) can offload some of this overhead to hardware (HW) that resides on the NIC. Offloading network processing to HW reduces CPU utilisation and network latencies, providing a more efficient system.

Guests with network processing workloads can optimise their configuration by availing of the hosts NIC offload capabilities. To avail of this optimal configuration, its important that a guest with NIC offload requirements is associated with a host platform NIC that provides the required offload capabilities, especially when the guest might need to perform within certain cpu utilisation, throughput or latency tresholds.

This blueprint will add the following support to Openstack:
(1) Discover and manage the usage of NIC HW offloads capabilities of its compute nodes
(2) Add support to guest scheduling/filtering that ensures a guest with NIC offload requirements is associated with a compute node NIC that provides the required offloads.
(3) Add support to guest scheduling/filtering that ensures a guest with NIC link speed requirements is associated with a compute node NIC that provides the required link speed.