KVM Forum 2018

This may come as a surprise but it is already possible to run nested KVM inside Hyper-V VMs and this includes several instance types on Azure. Such workloads, however, may not always perform very well. Some limitations come from x86 architecture and conceptual differences between KVM and Hyper-V, other issues could be dealt with within KVM. In this talk we will go through different performance bottlenecks of nested KVM-on-Hyper-V deployments. The presentation will highligh recent developments in the area: Englightened VMCS, Enlightened MSR-Bitmap, stable clocksource and others. We will also try to describe our work in progress and possible future improvements for nested KVM in general and KVM on Hyper-V in particular.