Virtualization costs something and the goals of any design should be to balance that cost against the benefits. I've designed systems that have crazy low-latenc

Virtualization costs something and the goals of any design should be to balance that cost against the benefits. I've designed systems that have crazy low-latency and high QPS needs and nothing beats bare metal for these systems. That said if you need to manage 5,000 of them you start to debate the advantages of having the application in a virtual environment against the cost of buying 600 more servers. In most situations the difference is noise against the backdrop of security, maintenance, labor to manage a system -vs- the performance needed. Sadly many people think virtualization and/or containers are "Free" and make uninformed decisions that have real impacts on systems at scale later in the system's lifetime. In general if you need the flexibility or your application is usually 5% CPU 95% of the time you'd better off doing some form of virtualization to save labor and maximize resource utilization of systems you're deploying. That said I agree with many of the comments here it would be nice to see more head-to-heads of hypervisors but that's scary stuff for the vendors involved and puts them at serious risk in the arms race to save every penny we can in managing large farms of applications and the systems running them. Remember, Virtualization is just a technology like anything else it has it's benefits and brings with it resource usage and challenges. There is no "Free Lunch".. :-)