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I was looking into emulating Linux on my Windows computer. Well anyways what do you think is the fastest emulator? Right now it seems to be Virtual PC 2007. One little thing though I have a dual core processor, does anyone know of an emulator that will actually use both cores? (ie simulate 2 processors and run each processor in a different thread or something like that)

Thanks

What i really would like to be able to do would be OS shifting.
fx.
i have linux and windows on my computer and though i can run both at the same time by the help of an emulator, it usually isnt very useably due to the masive memory consumption and cpu load.
However imagine this:
You are running linux and want to do something in wondows (dont ask me why) then you simply push a button and the linux system is dumped, with everything that relates to it in memory, to the harddrive, and the windows startsup, or if you allready have a dump of windows from a previous startup, it only need to be loaded in to memory.

If you have dual cores it might even be possible to run both OS' at the same time, allthough it would probably use a great deal of memory.

I am quite sure (some of) this is possible and i would be very amazed if someone havent done this allready, however i have never succeeded in finding any information about the subject.

Zacariaz wrote:I am quite sure (some of) this is possible and i would be very amazed if someone havent done this allready, however i have never succeeded in finding any information about the subject.

Xen?

Never seen it before.
As i understand it, it works like this:
Use have a computer with, fx a small linux dist installed in order to be able to run xen. Then you have some other oses lying around, either installed or as images or simular which can be run on top of xen.

Is this correct? I so it is a very nice idea but i would think that there could be certain... complication involved in doing it this way.

Zacariaz wrote:Is this correct? I so it is a very nice idea but i would think that there could be certain... complication involved in doing it this way.

I've never used it, and, in fact, know very little about it, however, it is my understanding that it uses modified disk images that use its own ABI (To increasing speed), extensive use of hardware virtualization, and advanced emulation techniques. I don't think speed would be much of a problem, especially with 2 or 4 cores.

One of the main problems is having to actually modify the child kernel.

yes, as i understand it an os would have to be "ported" (as they discribe it), however when talkin non opensource os that is a problem, and even with opensource it isnt just something you do.

My use for this would be to run both windows and debian. I dont know how much trouble debian would result in, but windows is a problem, The solution they say, is intels VT-x support, however ive tryed using that in vmware, without any noticable improvement. I other words, it sound great, but i have a hard time believeing it.

How about this (assuming you are using GRUB and you can access the config file from Windows (use an ext2 IFS or something)):

In Windows:
- Write a program that removes the default/timeout from your GRUB configuration file. Make it auto-start on start-up (use the registry/scheduler/Startup folder).
- Write a program that changes your grub configuration to default to Linux with a 1 second time out. Then place Windows into hibernation mode with reboot (the Windows Platform SDK should explain it all). Store a copy of the current system time. Keep looping until the current system time is about a minute past your old time (enough time to ensure your computer has actually hibernated and resumed) then run the first program.
- Place a short-cut on the desktop and label it "Switch to Linux".

In Linux:
- Write a program that removes the default/timeout from your GRUB configuration file. Make it auto-start on start-up (install it as a daemon, or on your Window-manager/shell startup).
- Write a program that changes your grub configuration to default to Windows with a 1 second time out. Then reboot with saving your session (most Window-managers have their own functions for this). Store a copy of the current system time. Keep looping until the current system time is about a minute past your old time (enough time to ensure your computer has actually hibernated and resumed) then run the first program.
- Place a link to it in /usr/bin and name is "SwitchToWindows" so you can type that in your favourite shell, or create a link to it on your favourite Window-manager's desktop/menu.

That would probably work, anyway it was exactly what i had in mind, only problem being that this is probably a tad to complicated for me.
It would be cool though, so ill take a wack at it.