During the development of Windows Server 2016 we spent a lot of time working on delivering the best core performance as a cloud platform. At the same time the Cloudbase team have spent a lot of time optimizing the performance of the Hyper-V OpenStack drivers as part of their work on the Mitaka release of OpenStack.
Just recently, they sat down and did a series of OpenStack benchmarks that compared OpenStack on KVM to OpenStack on Windows Server 2012 R2 and OpenStack on Windows Server 2016.
You can read about it in this series of blog posts:
Hopefully, you will not be surprised to hear that Windows Server 2016 wins the performance race in this comparison