Early on in the Windows 7 development process, we learned of something called MinWin. This was to be the most radical change to the Windows codebase yet, trading the aging NT kernel for an almost Linux-style system of compartmentalization. MinWin would represent only the base component of the OS, thus reducing its size, with other components layered on-top. Or so we thought. As development continued, MinWin's purpose shifted, and we learned it was not the compartmentalized wonder we once thought.
But according to some, Microsoft might just be revisiting their compartmentalized vision in an entirely new and radical way. While MinWin was all about splitting up the kernel into individual parts, a recent article from PC Magazine suggests that Microsoft should go a step further - splitting not just the kernel, but the operating system itself, with applications and services running in isolation from one another via virtualization. It sounds crazy, but it might just be what Microsoft needs to reinvent the modern OS.
The ability to simply suspend or start an application could be attractive.
What author Lance Ulanoff suggests is that Microsoft could possibly be turning Windows 8 into one giant virtual machine. Applications would no longer run as we currently know it, side by side in memory with other apps, but inside their own, dedicated virtual machine - a speedy, thin client that is segmented from the rest of the system, but still fully capable of behaving as a normal application. This whole process would, of course, be transparent. You wouldn't actually know you were running numerous, small virtual machines, but that's how the system would be set up.
In essence, it could spawn the ultimate crash-proof OS. Just as you can stop, start and freeze the contents of a virtual machine in VMWare or Parallels, so too could you with a Windows 8 application. This is also beneficial from a security standpoint; there would still be direct hardware access to things like graphics, or external drives, but the sandboxed nature of the machine prevents the rest of the system from being touched. If you're infected by a virus or other unwanted app, "that nastyware simply won't get further than the browser sandbox," explains Ulanoff. Sweet.
Parallels, for example, is a machine that virtualizes all aspects of a system, from BIOS to graphics, overhead that a Windows 8 implementation would theoretically reduce.
Considering Microsoft's previous work on the MinWin kernel, attempts to compartmentalize elements of the Windows OS have clearly been on the company's radar for some time (It's even used to some extent in Windows 7). In fact, if you examine trends in the business market, there might even be a corporate rationale as well. Many servers and data centers rely heavily upon virtual machines these days to split up processing power and hardware access to multiple clients. A perfect example of this is shared web hosting. However, these implementations most often rely on so-called "fat" clients - virtual machines that emulate an entire system, including the hardware and software. This takes a great deal of power, and a lot of fine tuning to keep multiple machines running smoothly.
Companies like VMWare, however, have been working on thin clients in an attempt to solve these problems. Thin virtual machines only virtualize specific components of a system — like the registry or other system variables — while sharing certain hardware components with the host OS. Virtualizing a web server, for example, wouldn't require unnecessary things like graphics or USB devices to be virtualized, reducing the overhead required for the environment to run. That equals more processing power to play with, and more efficient virtualized machines.
Windows 7's XP mode, where old and new coexist, is how Windows 8 should work by default, allowing Microsoft to make radical changes while continuing to provide legacy support.
Even if Microsoft fails to make such a large, sweeping change to their OS strategy, virtualization could still play a large part in other areas. Much as Apple did with OS X and its Classic mode many years ago, Microsoft could do away with the registry and other aging NT components, while still supporting older software through a virtualized layer. It could work very similarly to Windows 7's XP mode, but on steroids, completely seamless and segregated from the core OS.
Of course, every Windows development cycle is the same. Things like MinWin and WinFS, once slated to become core parts of the OS, were eventually dropped or modified in such a way that they were no longer what we expected. And while there may be signs now of a virtualized future, that too is subject to change. One thing is clear, there are big things coming for Windows 8 — it's the only way Microsoft can continue to survive.