Virtualization environments for the Mac have been popular applications ever since Apple made the move to Intel-based processors. Along with the move to X86-compatible processors came the ability to run Windows, Linux, and other popular OSes directly on the Mac's hardware. Even Apple itself got into the act, by releasing Boot Camp Assistant, an application that lets you install and run Windows on your Mac in a multi-boot environment.
Boot Camp was the first supported method for running Windows on Intel Macs, but Boot Camp has one drawback: It lets you run OS X or Windows, but not both simultaneously. Many users need a way to run OS X and Windows or another OS simultaneously, so they can access and exchange information between both environments.
Parallels pioneered virtualization on the Mac, with an application that allowed users to install Windows or Linux as a guest OS, and run both OS X and the guest OS simultaneously.
VMWare, a leading virtualization company on the Windows platform, soon joined in with Fusion, which can run Windows, Linux, and other OSes under OS X.
The third virtualization environment we will look at is from Oracle. When Oracle purchased Sun Microsystems, it acquired Sun's VirtualBox, a free virtualization application for the Mac. Parallels, Fusion, and VirtualBox are the three virtualization heavyweights on the Mac.
Virtualization on the Mac takes advantage of the fact that under the hood, the Mac uses the same technology that runs Windows and other OSes, including the same processor types, peripherals, memory, and other sundry parts.
You would think, then, that virtualization systems should be able to run as fast as a native implementation; that is, if you loaded the same computer hardware with just Windows or Linux, you should see comparable performance. Unfortunately that's not the case. Running a virtual environment has some overhead that can't be avoided. Since the virtual environment is running at the same time as the native OS (OS X), there has to be sharing of hardware resources. In addition, OS X has to provide some services to the virtualization environment, such as windowing and core services. The combination of these services and resource sharing tends to limit how well a virtualized OS can run.
The purpose of this series of benchmarks is to measure the performance of each virtual environment, to see how they compare against each other, and to see how they compare to the native performance of the OS running standalone in a non-virtualization environment.
With that in mind, let's find out how well the virtualization applications perform.