You can create OpenStack instances using DirectPath I/O and Single Root I/O Virtualization (SR-IOV) passthrough devices.

Important: This feature is offered in VMware Integrated OpenStack Carrier Edition only. For more information, see VMware Integrated OpenStack Licensing.

Passthrough associates a physical device with a virtual machine, reducing the latency caused by virtualization. The following table shows how passthrough is implemented in VMware Integrated OpenStack.

Table 1. Key Passthrough Components and Roles
Component Role
Nova compute
  • Collects the list of SR-IOV devices and updates the list of PCI device specifications.
  • Embeds the host object ID in device specifications.
Nova PCI manager
  • Creates and maintains a device pool with address, vendor ID, product ID, and host ID.
  • Allocates and deallocates PCI devices to instances based on PCI requests.
Nova scheduler
  • Schedules instance placement on hosts that match the PCI requests
  • Manages hosts in a dedicated compute cluster with NICs and hosts enabled for SR-IOV.
    Note: DRS rules do not apply to devices enabled for SR-IOV. Place SR-IOV hosts in a separate compute cluster.