Did you catch the latest video from Microsoft’s virtualization team? In this one, the Microsoft guys are making the argument that VMware somehow imposes a “virtualization tax” by inserting an additional layer in your datacenter architecture that Microsoft doesn’t need. I’m familiar with Microsoft’s Hyper-V architecture and knew that as far as the count of layers, it’s no different than VMware. So what has changed? Did Microsoft achieve the impossible and remove a complete layer from their virtualization architecture without so much as a service pack?
Here’s how the VMware architecture looks:
From bottom to top, I count four layers: 1) the x86/x64 hardware; 2) the hypervisor (VMware ESXi); 3) the guest OS in the VM; and 4) the application in the VM. It’s nothing surprising and the same diagram we’ve used for years to explain how our products work.
Now, let’s take a look at the latest Microsoft architecture using a diagram from their video:
Wow, maybe they’re right! I only count three layers. How did they do it? They got rid of an entire layer. Is virtualization now part of the guest OS? Maybe they figured out how to make their apps run directly on Hyper-V with no guest OS at all? It’s especially amazing when all the Hyper-V product presentations I’ve ever seen and even Microsoft’s own virtualization white paper on their web site use a diagram like this:
This picture clearly shows the same four layers as the VMware architecture with Hyper-V operating as a type 1 or “bare-metal” hypervisor running directly on the hardware. In fact, compared to the OS-free ESXi architecture, Hyper-V even adds in that extra copy of Windows Server 2008 you see on the left side. Should we count that as a fifth layer?
So, has Microsoft achieved a software miracle by fully eliminating one or two layers from the Hyper-V architecture? Are VMware users really stuck paying a “tax” due to an excess layer in our design? Or could it be that Microsoft has simply redrawn their pictures and changed their story on how Hyper-V really works? I’ll leave it to sharper minds than mine to uncover the answer to this mystery.
As to the Microsoft claims of costing one-third as much as VMware repeated yet again in their video, we ask that you not be fooled. Microsoft may give away Hyper-V with Windows Server 2008, but they are charging big bucks for System Center management and all the servers, databases and agents you need to compare with our combination of VMware ESX and vCenter. It’s not easy to figure out all the Hyper-V and System Center pieces required to run a given number of VMs, but we’ve done the hard work for you in our Cost-per-Application Calculator. Give it a try and you’ll see that, even without the VM density advantage you get with our exclusive memory overcommit capability, VMware costs about the same as Microsoft. You’ll also see that running just a few extra VMs per host with ESX operating at a very conservative level of memory overcommit quickly yields a 20-30% cost advantage for VMware.
Anyway, nice try with the sequel guys – do you have plans to make it a trilogy?