Table of Contents
What is the purpose of SR-IOV?
The single root I/O virtualization (SR-IOV) interface is an extension to the PCI Express (PCIe) specification. SR-IOV allows a device, such as a network adapter, to separate access to its resources among various PCIe hardware functions.
Should I enable or disable SR-IOV?
Enabled—Enables a hypervisor to create virtual instances of a PCIe device, potentially increasing performance. Disabled—Does not enable a hypervisor to create virtual instances of a PCIe device.
What is SR-IOV port?
An SR-IOV-enabled NIC is a standard Ethernet port that provides the same physical bit-by-bit function of any network card. The SR-IOV provides several virtual functions, which are accomplished by using simple queues to handle input and output tasks.
How do I know if SR-IOV is enabled in VMware?
Enable SR-IOV on a Physical Adapter Navigate to the host in the left navigation pane and click the Manage tab. Go to Hardware tab. Under PCI Devices option, select the physical adapter and click Configure SR-IOV option. In the populated window, select Yes to enable SR-IOV.
What is PCI passthrough?
PCI passthrough allows guests to have exclusive access to PCI devices for a range of tasks. PCI passthrough allows PCI devices to appear and behave as if they were physically attached to the guest operating system. PCI devices are limited by the virtualized system architecture.
What is PF and VF?
The physical device is referred to as Physical Function (PF) while the virtual devices are referred to as Virtual Functions (VF).
What is NIC passthrough?
This may sound a lot like what a virtual NIC and a vSwitch does, but the feature works very similarly to PCI passthrough, granting a VM direct access to the NIC hardware. In a nutshell, PCI passthrough allows you to give a virtual machine direct access to a PCI device on the host.
What is VM passthrough?
Passthrough mode, supported by Microsoft Hyper-V, Citrix XenServer and VMware ESX simply hands off the entire GPU to the hypervisor for the benefit of one VM. No carving or segmentation possible. This mode is more common for Citrix XenApp environments where a few VMs will be shared by many users.
What is SR-IOV and how does it work?
SR-IOV is a specification that allows a single Peripheral Component Interconnect Express (PCIe) physical device under a single root port to appear as multiple separate physical devices to the hypervisor or the guest operating system. SR-IOV uses physical functions (PFs) and virtual functions (VFs) to manage global functions for the SR-IOV devices.
Do I need a virtual bridge with an SR-IOV Nic?
With the introduction of SR-IOV based NICs, the traditional virtual bridge is no longer required. Each SR-IOV port is associated with a virtual function (VF).
How do I Reserve guest memory for my SR-IOV Nic?
Once you’ve got your new SR-IOV enabled NIC attached to the VM, you’ll need to reserve all guest memory. This is done by editing the resource settings for the VM: This is nothing new, and is the same requirement for any VM with PCI passthrough enabled.
What are SR-IOV physical and virtual functions (PFS)?
SR-IOV uses physical functions (PFs) and virtual functions (VFs) to manage global functions for the SR-IOV devices. PFs are full PCIe functions that are capable of configuring and managing the SR-IOV functionality. It is possible to configure or control PCIe devices using PFs, and the PF has full ability to move data in and out of the device.