vDPA-net Live Migration with Shadow Virtqueue

Explore the intricacies of vDPA-net live migration using Shadow Virtqueue in this KVM Forum talk. Delve into the concept of vDPA devices, which combine a virtio-compliant datapath with vendor-specific control paths, enabling high-performance data processing offloading while maintaining flexibility for device configuration. Learn how this unified interface facilitates VM migration between different device types, simplifying workload upgrades and scaling. Discover the Shadow Virtqueue (SVQ) technique, which provides an emulated queue to the device, allowing QEMU to track guest commands that affect device internal state. Understand how QEMU switches between passthrough and SVQ modes to balance performance and dirty memory tracking. Examine the details of Shadow Virtqueue implementation and its role in migration, minimizing device assistance requirements. Witness a demonstration of the technology in action and gain insights into future developments in this 26-minute presentation.