SR-IOV

Single-root I/O virtualization (SR-IOV) is a hardware-assisted feature that allows virtual machines to communicate directly with the physical hardware, bypassing the Hyper-V virtual switch and management operating system entirely. SR-IOV as a technology is by no means restricted to networking, but this is the only usage that will be covered in this book. As with RDMA, SR-IOV is typically only found on higher-end adapters, but it does not have any particular requirements otherwise.

An SR-IOV network adapter grants access to a Physical Function (PF) through a certain number of Virtual Functions (VF) that are made available for virtual adapters to use. These functions are a specific combination of hardware addresses and available function sets for utilizing a device. The PFs are how the hardware performs its duties while the VFs are how the PFs are made available to virtual adapters.

Remember from Chapter 5, Network Design, that a virtual switch must have SR-IOV enabled when it is first...