While pundits are getting all moist about the prospect of Windows 8 including Hyper-V hypervisor, there might be a few problems for those using older PCs and servers.
Hyper-V hypervisor has been under the bonnet of Windows Server 2008 and Windows Server 2008 R2, but last week Vole has announced that the client-side virtualisation will be included in Windows 8.
It looks like Windows 8 will use Hyper-V to do a number of tricks including new storage systems, memory, and networking enhancements, including a new virtual hard drive format (.vhdx) that allows for up to 16TB of data, as opposed to the 2TB limit of .vhd.
Vole will add support for four core CPUs and hardware acceleration.
But, according to CIO magazine, Hyper V requires 64-bit processors with Intel’s VT-x or AMD’s AMD-V virtualisation technology and have a Second Level Address Translation (SLAT). The 64 bit requirement might not be too tricky, unless you are dumb enough to want to jump from a Windows XP era machine to Windows 8, but SLAT is a little rarer.
SLAT is an updated version of hardware virtualisation that’s included in Intel’s Core i3, i5, and i7 and AMD’s latest Barcelona processors.
In the server world, where machines are not upgraded as often, the SLAT requirement is going to be a headache for those already running Hyper-V. Many will have to buy new servers if they want to run the server versions of Windows 8.
Hyper-V can run 32- and 64-bit guest operating systems, but will need to be controlled by a 64 bit overlord operating system with a bit more RAM than the conventional four gigabyes.
Microsoft appears to be hoping that corporates will buy a small amount of new gear and then run old gear virtually on the new stuff.
But there will still be features and software that depend on specific hardware which still do not work well in a VM. GPU based applications do not work well in a virtual environment and neither do things like BitLocker and Measured Boot.