SRIOV / Single root I/O virtualization

Bypassing the hypervisor's involvement in the communication between the Guest VM driver and the hardware/devices.
Physical(Hardware) device attached to host machine will appear as seperate device to each VM.
Hardware device must support SRIOV. Hardware device must provide an independent memory space, interrupts, DMA streams to each virtual machine

Physical and Virtual Functions

Physical Function? PFs are full PCIe functions ie access to complete PCIe space. This is provided to host OS.
Virtual Function? VFs provide to virtual devices.