VMware and My Alien Dream

I Had a Dream

An alien is loose in the city. I am hot on his trail, but he eludes me. Unable to catch him I head home. Then the hunter becomes the hunted. The alien is after me! I scramble through the streets in a panic. Out of breath, I turn and confront the alien at the door to my home. He seems pleasant enough, so I invite him in for tea and cookies.

He is very interested in my computer. I pop the lid off for him and from out of nowhere he produces a mass of silicone and wires. He hooks it into my computer and powers it on. I sit in wonder as my computer can now run multiple operating systems! UNIX, Windows, OS/2, even Macintosh are all running side by side and communicating with each other! The alien grins at me, then leaves while I sit and play with this new toy. I don't even have the chance to thank him!

For years I thought it was just a dream until a coworker told me about VMware. I jumped on their web site quick to download the alien's technology.

VMware: Alien Technology?

At first sight, it wasn't nearly as alien as I had dreamed. No Romulan characters in the display; just a regular old window. I entered the settings for my new virtual machine and powered on. My system beeped and I watched the BIOS information and memory count inside an X window. It checked the floppy drives for an operating system. Like any other new computer with no OS installed it choked. I almost did too: there was a computer inside my computer!

I scrambled to find some install disks to feed it. I chose Windows 98 to start with. It was handy. Later I would try NT Workstation and NT Server, and even another Linux distribution. All of these worked great. Unlike my dream, you cannot run Macintosh or BeOS, but supports most anything else that runs on Intel-based hardware. I don't often enjoy OS installs, having done too many of them in my life. But this one was an exception.

What You Can Expect

Virtual machines in a VMware environment are called guest systems; your regular machine is the host. You can display a guest system within a window or full screen at the click of a button or a command keystroke. In full screen mode the casual observer would not know it was a guest system. It is fast, almost as fast as if it were running all by itself.

In five months of use, VMware has only crashed on me once. I had run out of space on the drive that held the guest's virtual hard drive. VMware spat out an error (VMware Panic!) and died. But it restarted okay, and after deleting some stuff has given me no further problems. Of course Windows running within VMware is still crash prone; alien technology can't fix everything.

If you're using Windows as a guest system, get VMware's additional drivers for Windows. You will get better video color. Your mouse will move freely between the two systems and the systems clipboards will be synchronized. That last feature alone has me wishing someone would built a network tool to sink together the clipboards of multiple systems. I often have something I want to cut on one system and paste on another.

Some drawbacks

Windows sound output is choppy, sometimes scratchy. I wanted to take advantage of Windows multimedia support to browse some videos online, but the sound is horrible. Dings and chirps come through, but anything longer is a problem. This is a bug in VMware for Linux they claim will be fixed in a future release.

You can point to an existing operating system (like the dual-boot partition you were using before this came along.) Windows will insist on changing all your drivers to match the new virtual system. This makes it frustrating to switch back and forth from dual boot to virtual.

I got everything to work, but be careful when using things like disk partitioning tools on the guest system. I tried this and it rearranged my partition table numbering, and it took me a while to straighten that out. VMware suggests (and I agree) that you use a virtual drive partition rather than a real one. It seems safer to me: I don't want my guest system getting confused and messing up my real drives.

Netscape under Linux is a memory pig. While not specifically a VMware problem, it can slow your performance. I ended up bumping my system memory from 129 Mbytes to 256 Mbytes, and it ran a lot smoother. I still give the guest system only 64 Mbytes. That leaves me a reasonable amount for VMware to do its thing and still run Netscape without thrashing my swap space for memory. Close Netscape before launching VMware. Netscape seems to consume as much memory as you have. If it is already laying claim to memory that VMware wants, your system will slow to a crawl.

Everything else is what you would expect from a machine running two operating systems at the same time. They compete for the same resources. When neither system is hogging the CPU cycles, it runs smoothly. Run a couple of CPU-intense programs and the systems will start fighting each other while you are forced to wait it out. The drives can also be used by both systems, but will fight if both want a disk at the same time. To avoid this, you learn to let one system finish an intense task before starting a new one on the other. Which is just common sense. The same thing is true of any two processes on your system. VMware will behave no worse than any other application you are running.

Thanking the Alien

VMware is a great choice if you want to switch between operating systems frequently. It is cheaper than buying multiple computers, less irritating than dual booting your computer, and offers interesting possibilites you can't get out of either of the two previous methods (like the synchronized clipboards.) While not suitable for server systems, it seems great for development systems, test systems, technical support systems, or even a workstation for the person that always wants the best on all systems.

The technology turns out not to be so alien after all. As explained in the accompanying interview, it is really old technology with some new twists. There were obstacles to surmount to get it to work, but nothing came from Roswell. It is still a thrill for me, if a bit strange, to see the guest operating system boot inside of a window. It may not be alien technology, but I will always think of VMware's chief scientist, as the alien that made my dream come true. Thank you, Mendel Rosenblum!