What is the specific functionality of a PF(Physical Function) in SR-IOV ? Also what is the difference between virtual function and a physical function ? Does the VF communicate with a PF during the transfer of a packet from the VM ?

[idata]

What is the specific functionality of a PF(Physical Function) in SR-IOV ? Also what is the difference between virtual function and a physical function ? Does the VF communicate with a PF during the transfer of a packet from the VM ?@

[idata]

Hi Ygkumar,

Thank you for the post. 1) The specific funtionality of a PF in SR-IOV is actually refers to the physical NIC that includes the full feature of the PCI-e functions, it is to configure and manage the SR-IOV. .You may refer to page 13 at http://www.intel.com/content/www/us/en/pci-express/pci-sig-sr-iov-primer-sr-iov-technology-paper.html2) The difference between virtual function and physical function as follow:(based on page 13 of the website above) -Physical Functions (PFs): These are full PCIe functions that include the SR-IOV, Extended Capability. The capability is used to configure and manage the SR-IOV functionality. - Virtual Functions (VFs): These are 'lightweight' PCIe functions that contain the resources necessary for data movement but have a carefully minimized set of configuration resources (this is the virtual NIC) 3) You may refer to page 12, the sample shows that the 3 virtual machines are directly accessing to dedicated resources within the ethernet controller without passing the PF. http://www.intel.com/content/www/us/en/pci-express/pci-sig-sr-iov-primer-sr-iov-technology-paper.htmlThanks,wb

[idata]

Hi Ygkumar,

Good day. Please feel free to update me if further assistance needed?rgds,wb