In
virtualization, single root input/output virtualization (SR-IOV) is a specification that allows the isolation of
PCI Express
PCI Express (Peripheral Component Interconnect Express), officially abbreviated as PCIe or PCI-e, is a high-speed serial computer expansion bus standard, designed to replace the older PCI, PCI-X and AGP bus standards. It is the common ...
resources for manageability and performance reasons.
Details
A single physical
PCI Express
PCI Express (Peripheral Component Interconnect Express), officially abbreviated as PCIe or PCI-e, is a high-speed serial computer expansion bus standard, designed to replace the older PCI, PCI-X and AGP bus standards. It is the common ...
bus can be shared in a virtual environment using the SR-IOV specification. The SR-IOV offers different
virtual functions
In object-oriented programming, in languages such as C++, and Object Pascal, a virtual function or virtual method is an inheritable and overridable function or method for which dynamic dispatch is facilitated. This concept is an important part o ...
to different virtual components (e.g.
network adapter) on a physical server machine. SR-IOV uses physical and virtual functions to control or configure PCIe devices. Physical functions have the ability to move data in and out of the device while virtual functions are lightweight PCIe functions that support data flowing but also have a restricted set of configuration resources. The virtual or physical functions available to the
hypervisor or guest operating system depend on the PCIe device.
The SR-IOV allows different
virtual machines (VMs) in a virtual environment to share a single
PCI Express
PCI Express (Peripheral Component Interconnect Express), officially abbreviated as PCIe or PCI-e, is a high-speed serial computer expansion bus standard, designed to replace the older PCI, PCI-X and AGP bus standards. It is the common ...
hardware interface. In contrast, MR-IOV allows I/O PCI Express to share resources among different VMs on different physical machines.
InfiniBand
A major field of application for SR-IOV is within the
high-performance computing (HPC) field. The use of high-performance
InfiniBand networking cards is growing within the HPC sector, and there is early research into the use of SR-IOV to allow for the use of InfiniBand within virtual machines such as
Xen
Xen (pronounced ) is a type-1 hypervisor, providing services that allow multiple computer operating systems to execute on the same computer hardware concurrently. It was
originally developed by the University of Cambridge Computer Laboratory an ...
.
[http://datasys.cs.iit.edu/reports/2014_IIT_virtualization-fermicloud.pdf ]
See also
*
I/O virtualization
References
{{Reflist
Hardware virtualization
Computer networking
Peripheral Component Interconnect