Planning for the Use of PCIe SR-IOV Virtual Functions

Plan ahead to determine how you want to use virtual functions in your configuration. Determine which virtual functions from the SR-IOV devices will satisfy your current and future configuration needs.

If you have not yet enabled I/O virtualization, which requires using the static method, combine this step with the steps to create virtual functions. By combining these steps, you need to reboot the root domain only once.

Even when dynamic SR-IOV is available, the recommended practice is to create all the virtual functions at once because you might not be able to create them dynamically after they have been assigned to I/O domains.

In the static SR-IOV case, planning helps you to avoid performing multiple root domain reboots, each of which might negatively affect I/O domains.

For information about I/O domains, see General Guidelines for Creating an I/O Domain.

Use the following general steps to plan and perform SR-IOV virtual function configuration and assignment:

1. Determine which PCIe SR-IOV physical functions are available on your system and which ones are best suited to your needs.

   Use the following commands to identify the required information:

   ldm list-io

   Identifies the available SR-IOV physical function devices.

   prtdiag -v

   Identifies which PCIe SR-IOV cards and on-board devices are available.

   ldm list-io -l pf-name

   Identifies additional information about a specified physical function, such as the maximum number of virtual functions that are supported by the device.

   ldm list-io -d pf-name

   Identifies the device-specific properties that are supported by the device. See Advanced SR-IOV Topics: Ethernet SR-IOV.

2. Enable I/O virtualization operations for a PCIe bus.

   See How to Enable I/O Virtualization for a PCIe Bus.

3. Create the required number of virtual functions on the specified SR-IOV physical function.

   Use the following command to create the virtual functions for the physical function:

   primary# ldm create-vf -n max pf-name

   For more information, see How to Create an Ethernet SR-IOV Virtual Function, How to Create an InfiniBand Virtual Function, and How to Create a Fibre Channel SR-IOV Virtual Function.

4. Use the ldm add-config command to save the configuration to the SP.

   For more information, see How to Add an Ethernet SR-IOV Virtual Function to an I/O Domain, How to Add an InfiniBand Virtual Function to an I/O Domain, and How to Add a Fibre Channel SR-IOV Virtual Function to an I/O Domain.