vTeardown

vSphere over Hyper-V: create 8 vCPU VMs for any of the 55 vSphere supported OSs. Hyper-V supports only up to 4 vCPUs and then only for Windows Server 2008 and Windows 7

vSphere currently supports 55 guest operating systems – maximum flexibility for deploying applications in a virtual environment

On the guest operating system support side, VMware ESX supports far more guest operating systems than any other bare-metal virtualization platform. In fact, VMware supports 55 different OSs ranging from Windows, OS/2, Solaris, and even NetWare (yes, a lot of people still use NetWare!) Visit the online VMware Compatibility Guide and you’ll see that ESX4 supports over 460 versions of those 55 OSs:

vSphere VMs scale up to 8 vCPUs and 255 GB of RAM – maximum scalability to take advantage of today’s hardware

What’s even more exciting is that for each one of those 460 versions of the 55 supported guest operating systems, ESX enables up to 8 virtual CPUs. Be it Windows or Linux, any ESX4 VM can be configured to have 8 vCPUs along with 255GB of RAM—the exception being Windows XP and Vista, which has an OS limitation of 2 vCPUs even when running natively on physical (Hyper-V on the other hand only supports up to 64GB of VM RAM). With this support, maximum throughput achievable from a single VM is much higher in ESX4 than in previous versions.

ESX4 even allows one to configure vCPUs in odd numbers such as 3, 5, or 7 if one chooses. This ability allows application workloads to be configured with the most flexibility:

Hyper-V limits choice, treats Linux VMs as second-class citizens and doesn’t scale to the full potential of today’s hardware

In contrast, Microsoft Hyper-V has a much smaller guest OS support list along with very limited vSMP support. Take a close look at their guest operating system support list and you’ll notice Windows 2008 and Windows 7 VMs are limited to only 1, 2, or 4 vCPUs. In addition, Hyper-V Linux VMs are hindered by only 1vCPU. Don’t even try running SAP on a Linux VM under Hyper-V because it’s NOT supported! SAP does not even plan to evaluate this type of combination for their applications. On the other hand, ESX has supported SAP in both Windows and Linux VMs since 2007.

In addition to Linux, legacy systems, even Windows legacy systems, are also treated as second-class citizens. Where’s the 4 vCPU support for Windows 2003? Or how about 2 vCPU support in Windows 2000? Can’t do it on Hyper-V!  Could Microsoft be limiting support for legacy Windows systems to “encourage” upgrades to newer OSs? Hmm – VMware does not have that type of conflict of interest. ESX4 does a better job at running Windows OSs than Microsoft by supporting practically every Windows version since 3.1 and even MS DOS 6.22! Alright, I know we don’t support Windows ME (Mistake Edition), but then again, who’s willing to admit that they’re running the worst OS of all time?

The Bottom Line

Virtualization should not be used as a vehicle to influence a customer’s choice of guest operating systems or when they should do an operating system upgrade. VMware strives to support guest operating systems as consistently and equally as possible. On the other hand, Microsoft’s preferential treatment of Windows Server 2008 and Windows 7 pressures companies to deploy these OSs in order to get the full benefits of Hyper-V. If a guest OS doesn’t generate any revenue for Microsoft, it most likely won’t show up on their guest support list. Do you think Solaris will ever make the list?

With the introduction of 6 core CPUs and with 8 cores just right around the corner, customers need a virtualization platform that can take advantage of the increased processing power. VMs under ESX4 does just that with support for up to 8 vCPUs and 255GB of RAM. On the other hand, Hyper-V comes up short and is not yet enterprise-ready, as noted pointedly by Burton Group.