AnandTech has written an extensive article about hardware virtualization:
While a lot has been written about the opportunities that virtualization brings (consolidation, hosting legacy applications, resource balancing, faster provisioning...), most publications about virtualization are rather vague about the "nuts and bolts". We talked to several hypervisor architects at VMWorld 2008. In this article, we'll delve a bit deeper as we look to understand the impact of virtualization on performance.
Performance? Isn't that a non-issue? Modern virtualization solutions surely do not lose more than a few percent in performance, right? We'll show you that the answer is quite a bit different from what some of the sponsored white papers want you to believe. We'll begin today with a look at the basics of virtualization, and we will continue to explore the subject in future articles over the coming months.
In this first article we discuss "hardware virtualization", i.e. the technology that makes it possible to offer several virtualized server such as VMware's ESX, Xen, and Windows 2008's Hyper-V. We recently provided an introduction to application virtualization using Thinstall, SoftGrid, and others software packages at our new IT portal, it.anandtech.com. These articles are all about quantifying the performance of virtualized servers and understanding virtualization technologies a bit better.