Full System Virtualizing (How to limit processor speed?)
 

Hello everyone,

I have joint (virtual)hardware-software issue. I would appreciate any hints you might have. The information is as follows:

[A] BACKGROUND:
I have been looking for a cheap old laptop that I might run Linux on. My good laptop is basically a desktop replacement and not good for carrying around. Sellers out there have all sorts of different configurations and I have been trying to emulate their specs to see which distribution would be best suited to that particular machine.

[B] GOAL:
To FULLY emulate a computer so that I have full control over how much processor power (mhz) I allow it, how much HDD space (gb) and how much RAM (mb).

[C] PROBLEM:
I have looked into VIRTUALBOX, QEMU, and VMWARE Player:

1. Virtual Box and Qemu:
I have been able to set the RAM and HDD but I am not sure how to limit the processor speed.

2. VMware Player:
Haven't had much success at all with it mainly because I despise the idea of having to DOWNLOAD virtual images and registering with the company for VMWARE SERVER if I want to create my own images. It's frustrating and feels restricting, almost anti-open source. However, I am willing to give it a shot if it can allow full virtualization of the processor, ram, and hdd.

[D] POSSIBLE SOLUTIONS:
1. I COULD perhaps edit my BIOS and limit the clock speed? (Though that defeats the whole purpose of virtualizing)
2. Is there another virtualizing software that I might use?
3. Is there a way to limit processor power given to a virtual machine using VIRTUALBOX, QEMU, VMWARE, or any other virtualization software?

Thanks for your help

1) Hardware level virtualization or paravirtualization as it is called, is supported in only some recent processors. In para-virtualization, the guest OS runs at near native speed.

2) Your Virtualization software should support para-virtaulization. Try Xen on Linux or recent version of Microsoft Virtual PC which support this technology (Sorry for mentioning Microsoft on Linux Forum, but it is one of the solution to your problem).

1) Why do you want to emulate the specs? Just check Linux compatibility list on Internet for your laptop, so Linux works fine on your particular laptop.
2)Some Linux distributions better support some systems than others check your favorite Linux distribution for compatibility.
3)About performance, command-line mode, X-windows (Xbox, fluxbox, enlightenment,etc.), Full GUI(KDE,GNOME) will require more swap, ram and processor power in the order they are mentioned.

I don't think you can limit processor power on a uniprocessor or a multiprocessor. I guess, clusters can be configured to do that.
No virtualization software currently supports limiting processor power.