Physical Volumes!!

R

rxcited

Bit poster
I can't believe I am the only one thinking about this. I've been on the bleeding edge since XOM was released a short number of weeks ago. As soon as Apple announced Boot Camp, I was on it. So here I have a separate dedicated partition setup with XP installed, configured, dual-bootable, (soon to be) activated, and with a bunch of software installed on it. Now comes along Parallels. I have to reinstall the OS, reconfigure the software, and waste more space.

I would really love to stay booted in OS X most of the time. I would run Parallels booted off of my FAT32 XP partition for occassional/regular Windows use. If/when I needed full performance for gaming or 3D CAD software, I would reboot my Mac into XP. This would rock!

To achieve this, I see two major requirements:

1. Parallels needs to support physical drive partitions.

2. Somehow the different drivers required when booting under the VM versus under the real hardware needs to be addressed. Certain configuration files might also need tweaking when this switch is made (e.g. boot.ini for Windows).

For number 1, it seems like this is already happening when using the real CD/DVD option (though CD only for now and not writable). So it doesn't seem like too much of a stretch for Parallels to support read/write for physical hard disk partitions. If needed, the volumes could be unmounted from OS X, but it would be convenient as a file sharing mechanism if it could stay mounted by OS X while in use by Parallels. As for number 2, maybe a clever use of hardware profiles and swapping of boot.ini files could be used to allow the volume to boot under the VM or the real hardware as needed?

This would be SUPER cool!! :D
 
Hi rxcited,

you're absolutely right - booting from an already existing WinXP partition would be great. Alas, as Parallels sports some own virtual devices, like the Parallel VGA Bios, I would assume some troubles every time you swicht from Parallels to BootCamp and vice versa, since Windows would have to reconfigure its drivers all the time. Plus that the Apple drivers do not work at all when running the VM under Parallels.

But anyway, booting from one partition would be really great!

Cheers,
Budy
 
Hi Budy

Yeah I wouldn't expect the Apple Boot Camp drivers to work under Parallels. Those drivers are for the Apple hardware which is different than the virtual environment emulated within Parallels. This is precisely what my #2 point was all about. It is possible under NT/W2K/XP at least, to have different hardware profiles. I've never used them, but they allow you to have a set of different configurations, each of which correspond to a different set of hardware with associated configured drivers.

Although it might be tedious, in theory the idea would be to select a different hardware profile when booting under Parallels and another profile when booting under Boot Camp. You won't find different hardware profiles to choose unless you have saved some. You can do this under Windows using Control Panels / System / Hardware (tab) / Hardware Profiles (button). Maybe it would be possible to have Parallels select its preferred hardware profile when it boots and reset the default hardware profile to the needed set for booting the Mac hardware?

Related to this is the boot.ini settings. For example, under Parallels, my boot.ini file is set to "multi(0)disk(0)rdisk(0)partition(1)\WINDOWS" whereas the boot.ini file on my Boot Camp partition says "multi(0)disk(0)rdisk(0)partition(3)\WINDOWS". Note the partition number is different. So the boot.ini file would need to be adjusted to boot under the two different environments or maybe Parallels could inspect the boot.ini file on the physical volume and emulate the required partition arrangement to allow booting with the boot.ini as is.

This all seems doable to me. This would make Parallels an incredibly optimal enhancement for the Boot Camp OS X user. Worth well over $50, IMNSHO!! :D
 
Booting both raw and in a virtual environment from the same partition seems to me to present a real technical challange. I'd be happy with a utility to copy a Windows partition into a VM, substituting drivers and editing the registry as needed. Since we're only dealing with one version of XP, it should be doable. This would give us the ability to use boot camp for now to set up a Windows environment, and when the VM software is released with all the features needed for a given user (ie me), we would have an easy migration path -- copy the Windows partition to a VM, test it, burn the Windows partition, recover the space, and keep running. Given Microsoft's <explitive deleted> "activation" (AKA we're criminals until proven otherwise) requirement, reactivation may be required, but that, annoying though it may be, is surmountable. (Can you tell what I think of activation?)
 
Physical Disk Access

I too would love to see physical disk access implemented on a per partition basis. I don't want to be able to share a physical partition with the host OS nor with another guest OS. The virtual file system is causing me to use twice the physical space on my pc :( bummer.

Thanks
 
sync or share home directory for the first implementation

I am certainly happy if I could use the same Windows installation for Boot Camp and Parallels.
However, It seems difficult to share the core part of the Windows OS. So that I would suggest
a step by step implementation before full functionability.

1. Syncing capability between home directories in BC and VM.
For this purpose at least we must mount real windows partition into VM, and mount .vhd disk
image in real Windows.

2. Sharing home directory between BC and VM.
The next step would be a function to use the same physical home directory by VM and real
Windows.

I think such simple implementation helps us very much already. A utility to mount .vhd disk
image in Windows is rather urgent request that allows us to maintain the virtual hard drive
smoothly. For example, virus checking of older windows system drive, installation of older OS that
does not support CD boot, etc.
 
Sharing between Boot Camp and VM has several issues.

XP systems can handle the technical problems of multiple boot configurations. That is not so much a problem.

The real problems extend from things like Windows Activation. Whenever you make such a "significant hardware change", MS will want you to re-activate Windows. You see, Windows will think that going from Boot Camp to Parallels is the same as a complete motherboard replacement.

I suspect that Microsoft will be the ones to bank on this, with Virtual PC for Mac that has a corporate-edition of XP, no Activation, and proprietary boot configuration scripting so that VPC will go with boot camp. Of course, that requires two things; the MBU to have half a brain, and, of course, a leadership that would let them develop such a product.

I don't think this is going to happen with Parallels, unless they chose to support pirated copies of Windows that lack product activation.

Edit: As for accessing an existing home folder on BC, you can do that currently with a drive share. That will work for file access, but since boot configuration has changed, you really can't link local folders due to the different environments.
 
Last edited:
One more vote for physical volumes support!!

I have a different take on it, though, and brings with it another Wish List request -- support for USB and Firewire drives.

I have a number of legacy Windows drives (98SE, 2000, and even XP) that I'd like to just be able to use to boot into a VM. Hate to suck up my Mac mini's itty bitty hdd space (80GB) creating drive images out of these physical drives, and after I imaged 'em what will I do with the legacy drives? Toss 'em into an ATA RAID? Hardly worth sucking up good RAID space for these (generally low-capacity) drives.

Parallels team, let's see physical volume support in a soon-to-be-released version, PLEASE!!

Meantime, keep up the good work!
 
rxcited said:
1. Parallels needs to support physical drive partitions.
Click to expand...

Nice concept, but perhaps not based in knowledge of the technology. If you would look at WinPro, VMware, QEMU, XEN you would discover that all of these virtualizers have this same 'limitation' as Parallels. Parallels is the latest product to enter this marketplace and they have done some much better things. But clearly there is a limitation in virtualization that prevents this - possibly referred to as the difficulty building a 'stack' of disk accesses that would interact with the host in an asynchronous manner and still not impact overall performance. Using a virtual drive means that only one process is accessing one disk file. Expanding that to random disk accesses to many files is magnitudes more difficult. All of the many developers of the competing products must have thought about this concept long ago, but for some reason never implemented it either. I think that the only way this could ever happen is to use a real-time kernel than doesn't exist in Windoze, OSX and Linux now.
 
Chris Price said:
Sharing between Boot Camp and VM has several issues.

XP systems can handle the technical problems of multiple boot configurations. That is not so much a problem.

The real problems extend from things like Windows Activation. Whenever you make such a "significant hardware change", MS will want you to re-activate Windows. You see, Windows will think that going from Boot Camp to Parallels is the same as a complete motherboard replacement.

I suspect that Microsoft will be the ones to bank on this, with Virtual PC for Mac that has a corporate-edition of XP, no Activation, and proprietary boot configuration scripting so that VPC will go with boot camp. Of course, that requires two things; the MBU to have half a brain, and, of course, a leadership that would let them develop such a product.

I don't think this is going to happen with Parallels, unless they chose to support pirated copies of Windows that lack product activation.

Edit: As for accessing an existing home folder on BC, you can do that currently with a drive share. That will work for file access, but since boot configuration has changed, you really can't link local folders due to the different environments.
Click to expand...

Ultimately, this is the real reason for this request. I don't want to have to purchase two full licenses for Windows. Is the following possible? Use a full version of Windows for Boot Camp and an upgrade version for Parallels.
 
VMWare can use physical partitions... i installed an OS using that, and I was able to *native or virtual* boot from this partition afterwards. Therefore, it's possible... as soon as GUID is not a problem, maybe it is...
 
I'd like to be able to access my physical USB floppy drive, as well as keychain drives and the like, from within my guest OSes.
 
You must log in or register to reply here.
Back
Top