Viridian – Better Late than… Early?

The big news today is that the Hypervisor for Windows Server Longhorn (codenamed Viridian) is being delayed.  See the Windows Server Division Blog for the main details.  On the surface it seems like this is bad news.  Many of us would like to move to the new Hypervisor ASAP.  From a strategic standpoint, I think it’s most important for Microsoft to ship a rock-solid first version of the Longhorn Server Hypervisor.  So is Microsoft doing the right thing?

When I first heard about the goals for Viridian (which were then pretty closely guarded), I thought that this “feature” was enough to warrant a new release the Windows Server platform (post-Longhorn Server).  At the very least, it could have commanded a “Virtualization Edition” of the product.  It’s no small architectural task to provide for the dynamic addition of hardware, support for large parallel processing, dozens of VMs, etc.  Goals include the ability to easily transition from at least Microsoft Virtual Server (and, perhaps, competing solutions – the names of which may or may not begin with the letters “V” or “X”).  And, it’s a new product – this isn’t a rebranding of another platform.

Microsoft states that scalability (and related testing) is a major reason for the delays.  Given that quality (measuring by reliability, stability, performance, etc.) is not up for compromise, I would have preferred to see Microsoft do a smaller initial release of the Hypervisor.  Perhaps an initial “lite” version that focused on the architecture of the product would have been a better approach.  While running on 64-CPU machines is definitely a plus, I’d rather have a more scaled-down version of the Hypervisor available earlier.  That would allow for determining migration paths, better understanding capacity planning, and for performing initial testing.  With that available, Microsoft could then focus on scalability to very large environments.

Regardless of the release timing, I think we’ll all eventually look back and say that Viridian was worth the wait.  Until then, we’ll have to rely on the many first- and third-party products that are available today.