Apple’s Boot Camp program allows Intel Macs to boot directly into Windows XP (Pro or Home versions) and run it natively, with full support for accelerated graphics and hardware devices (other than the built-in iSight camera, that is). But rebooting is time-consuming, and Mac users would much rather stay in Mac OS X and just run Windows when needed. Plus, Boot Camp only supports Windows XP.
Enter Parallels, an Mac OS X solution for running ‘guest’ operating systems within OS X. Parallels utilises the Intel chip’s hardware virtualisation technology (VT). This means that VT lets an Intel processor act as if it were several distinct processors, which in turn enables guest operating systems to run much faster.
What it really means to you, the user, is that you can run a wide variety of operating systems, including multiple versions of Windows and multiple versions of Linux, at good speeds, without ever rebooting your Mac.
Parallels doesn’t include any operating systems, so it’s up to you to supply them. In the case of Windows, you’ll need the actual installation CDs. For Linux, you may have image files (.iso) or burned CDs, depending on the source of the Linux distribution you’re using. Simply insert the installation CD, press Play in the Parallels interface, and the virtual machine will ‘boot’, which begins the actual operating-system installation process.
The guest operating system has no clue that it’s being installed on a machine running a virtual version of a computer under Mac OS X. Depending on which operating system you’ve chosen, you’ll spend anywhere from 10 to 45 minutes completing the installation. For instance, we installed Windows XP in about 30 minutes – basically the same amount of time it takes to install XP on a PC.
To test Parallels’ performance, we ran WorldBench 5, the official PC World testing tool, on a 20-inch 2GHz Intel iMac and a 15-inch 2.16GHz MacBook Pro. We compared those results with the same machines running Windows XP Pro natively via Boot Camp, and with a few actual PCs.
Using Parallels on the Macs, the overall test score was about two-thirds of what it was for the same machine booted natively into Windows via Boot Camp. Some portions of our tests, such as multitasking, showed a big divide in performance. Other portions showed only slight differences. In the Office 2002 test, for example, Parallels was just 10 per cent slower than in native mode.
How do these benchmarks translate to real life? We performed a few additional tests to simulate some common tasks. Running Microsoft Office on a 1.66GHz Core Duo mini with 2GB of RAM the speed was impressive. We were hard pressed to tell any difference between scrolling through a long Word document in Parallels and scrolling through that same document when booted into Windows via Boot Camp. Even using applications that perform very complex computations, such as Photoshop CS2, you’ll see good results.
To get the most out of Parallels, you’ll want to give your Mac as much RAM as you can afford – 1GB is enough to run Parallels alongside a few other programs. However, 2GB is much better, particularly if you’re going to run multiple operating systems at the same time or run a lot of large applications within your virtual machines.
Parallels’ ability to run nearly every version of Windows, along with many versions of Unix and Linux, makes it a valuable tool for anyone using an Intel-based Mac who has a need or desire to work with other operating systems. If you put the Parallels session in full-screen mode, anyone walking by won’t even be able to tell that under the Windows façade, you’re actually running the world’s greatest operating system.