View Full Version : Understanding Parallels, VMWare, etc.

28th January 2008, 10:14 AM
I am simply a small business user of computers and don't have the understanding of much in the way of the back end of a computer.

With say the Parallels or VM software my understanding is that to use MS programs you will always be in the Apple OS with the Windows/Vista simply being another "Tab or app" on your computer.

Therefore my question is - does having two operating systems running at the same ie me using "Pages" and me also wanting to use a Windows based software ie a database our small business uses create a taxing result for the computer. we would have the PC database and other one or two other PC softwares open all day.

ie is two OS's running at the same time creating a large drain on the computer??

Is it noticeable in running speed?

Is it even worthwhile to go to Apple if we need to have both OS's open all day?

28th January 2008, 11:03 AM
You can leave VMware or Parallels running all day, but your assumption is correct - it will use up system resources.

I guess it really depends on how much performance the apps you are running need.

As an aside, stability is pretty good, but I'd still hesitate to trust Parallels or VMWare with system-critical 24/7 tasks just yet.

28th January 2008, 11:03 AM
Think of Parallels or VMware Fusion running say Windows XP Pro virtually as just running another application (much like running say iTunes). It will use ram and cpu just like any other program.

Of course the guest operating system can be configured for a certain amount of memory. In this case the best default for Windows XP Pro guest/virtual machine would be 512mb.

This means the Windows XP Pro guest/virtual machine will think it has 512mb ram and of course it will then use 512mb + some other overhead from Parallels or Fusion from the machine running it. So it might use say 768mb ram from the OSX system to run this.

Performance wise, I find the guest operating system XP Pro with 512mb allocated to be perfectly fine. Not used for gaming, but for general use perfectly fine.

If the application in Windows consumes lots of CPU usage, then a core on the machine will then be seen to use lots of CPU (less cpu for OSX applications).

Hope this helps a little.

28th January 2008, 11:43 AM
Get 2GB of memory at the minimum if you want to virtualize.


Johnny Appleseed
28th January 2008, 11:53 AM
Yep, the more RAM you throw at it, the faster it'll be!

28th January 2008, 02:06 PM
You can set either program to prioritise Mac OS X or Windows programs. Otherwise, as JA stated, having a lot of RAM will help, as will having your VM disks (they are just very large files) on a second hard disk rather than your main one.