- OS-level virtualization is an operating system paradigm in which the kernel allows the existence of multiple isolated user space instances. Such instances, called containers (LXC, Solaris containers, Docker), Zones (Solaris containers), virtual private servers , partitions, virtual environments (VEs), virtual kernels (DragonFly BSD), or jails (FreeBSD jail or chroot jail), may look like real.
- Honest, Objective Reviews. PCMag.com is a leading authority on technology, delivering Labs-based, independent reviews of the latest products and services.
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Last week I took delivery of a shiny new iMac. I'll talk about it next week, but today I want to talk about running Windows on it.
Like most people who want Windows, I used Boot Camp. As it turns out, Boot Camp, appears to be nothing more than an application to non-destructively repartition your hard drive and create a disk of Mac drivers. Unlike the impression it gives that it does something to your Mac to make it possible to install Windows.
I ran and installed Windows on my iMac fine without even the Apple drivers - although of course networking and sound didn't work and the display was not ideal. But if those things weren't important II could have had a usable and bootable version of Windows on my iMac without any use of Boot Camp.
I encountered one problem though - you must install Boot Camp on a hard drive with only a single partition. It was then that I discovered Boot Camp isn't necessary to run Windows. Needing multiple partitions for OS X, I set up a multi-partitioned hard disk and then installed Windows on one partition anyway - something Boot Camp wouldn't let me do. If you're interested, instructions can be found on CrossOSS.
Like anyone though, I don't really want to reboot every time I need to use Windows - despite it being only occasionally.
And like anyone, I was really keen to check out the acclaimed Parallels. That was a GREAT disappointment. It doesn't work on my new iMac Core 2 Duo. It runs and lets you create a virtual system, but when you try to fire up that system, Parallels cause a kernel panic. The Grey Screen Of Death. It's quite entertaining the way that grey curtain of death sweeps down from above.!
Q to the rescue
With little optimism, I decided to give Q a go, assuming if Parallels couldn't have a working version on the Core 2 Duo Macs, what hope would Q have?
A couple of hours later, I had fully working versions of both Windows 98 and Windows XP running in Q. And running quite quickly and quite satisfactorily.
From the Q website:
Q is based on the excellent open source CPU emulator QEMU from Fabrice Bellard. Pierre d'Herbemont from stegefin.free.fr ported QEMU to OS X and initiated a cocoa Version.
That was the initialization for Mike to develop Q. A completely rewritten cocoa port of QEMU, built directly on OS X, making use of Apples Core-technologies like Core-image, Core-audio and OpenGL for in- and output, saving the overhead of cross platform APIs like SDL, FMOD or GTK.
Q in action
Q virtual systems are called Guests. Q provides several default Windows configurations for each version of Windows. If you want to install Linux or another OS, you need to manually configure your Guest.
Q can also emulate non-native CPUs. Thus if you run it on a PowerPC Mac, it will emulate x86, and vice-versa. Other CPUs Q can emulate are: x86-64, PPC PREP, SPARC-32, MIPS and ARM.
Windows 98
Windows 98 runs as fast as any PC I ran it on in the late ‘90s but it did display its legendary instability, with Internet Explorer crashing when it tried to view some websites.
The virtual display driver that Q used for Windows 98 (a Cirrus Logic 5446 PCI) worked fine and gave me 24-bit color up to 1024x768 pixels, and 16-bit up to 1280x1024.
The virtual soundcard Q defaults to is a Soundblaster 16 and this worked well although did stutter if the processor was busy.
The virtual network adapter also works fine, an NE2000.
Notably though, the CD drive (on my system a CD & DVD burner) only configures as a CD-ROM.
Virtualisering For Mac Torrent
Windows XP
Windows XP runs reasonably fast and is certainly quite usable. Like the Windows 98 Guest, sound is choppy and my DVD is only usable as a CD-ROM. Networking and display also work fine.
Linux
I successfully installed Freespire. Initial impressions are it is slower than either of the two Windows I installed.
Windows eye opener
Running Windows was an eye opener after three years as a Mac user. Mind snares: alices journey for mac. So many things you take for granted on Windows when that's all you know. Things like a plethora of questions, balloons popping up everywhere and restarts for most software installations. They all drive Mac users to distraction.
But still, it served my purpose. My major need for Windows is checking if my website designs work in Internet Explorer. And as so often happens, I discover that my sites don't work in IE so back to the drawing board. Q make this process simple and has cost me nothing (as I already owned a copy of Windows XP).
Shortcomings and Bugs
The lack of a driver to support CD burning and any type of DVD access is an issue that needs to be addressed by the developer. To install from a DVD requires converting the DVD to an ISO. Use Disk Utility to make an DMG image of the DVD and then the command on this page at Tech-Recipes to convert that to an ISO.
On both Windows installations I encountered a crash on the first reboot of the installation process which required rebooting, but thereafter, had no further problems with the install, or since.
If you 'Save the state' of a Guest, when it restores it is hung, and needs restarting. I found this with both Windows and Linux (although I did not have this problem on my PowerBook G4). This is a bit of problem if you intend to use Windows regularly on an Intel Mac - although the boot up time is very fast.
And yes, Q does knock system performance around, especially if you up the memory of your Guest system.
Overall
Sure Q has some issues to resolve, but it is still in beta and it is free. From my experience, I sugges you give Q a look before you try Parallels if your looking for a virtualization solution on Intel Macs. If Q meets your needs, why would you bother paying for Parallels? And given Parallels is not even working on the latest Macs, it'd score a zero, while I'd give Q a 7.5/10.
HOW VIRTUALIZATION WORKS
Virtualization 101
Due to the limitations of x86 servers, many IT organizations must deploy multiple servers, each operating at a fraction of their capacity, to keep pace with today's high storage and processing demands. The result: huge inefficiencies and excessive operating costs.
Enter virtualization. Virtualization relies on software to simulate hardware functionality and create a virtual computer system. This enables IT organizations to run more than one virtual system – and multiple operating systems and applications – on a single server. The resulting benefits include economies of scale and greater efficiency.
Virtual Machines Explained
A virtual computer system is known as a 'virtual machine' (VM): a tightly isolated software container with an operating system and application inside. Each self-contained VM is completely independent. Putting multiple VMs on a single computer enables several operating systems and applications to run on just one physical server, or 'host.'
A thin layer of software called a 'hypervisor' decouples the virtual machines from the host and dynamically allocates computing resources to each virtual machine as needed.
Key Properties of Virtual Machines
VMs have the following characteristics, which offer several benefits.
Virtualization Macbook Pro
Partitioning
- Run multiple operating systems on one physical machine.
- Divide system resources between virtual machines.
Isolation
The virtual soundcard Q defaults to is a Soundblaster 16 and this worked well although did stutter if the processor was busy.
The virtual network adapter also works fine, an NE2000.
Notably though, the CD drive (on my system a CD & DVD burner) only configures as a CD-ROM.
Virtualisering For Mac Torrent
Windows XP
Windows XP runs reasonably fast and is certainly quite usable. Like the Windows 98 Guest, sound is choppy and my DVD is only usable as a CD-ROM. Networking and display also work fine.
Linux
I successfully installed Freespire. Initial impressions are it is slower than either of the two Windows I installed.
Windows eye opener
Running Windows was an eye opener after three years as a Mac user. Mind snares: alices journey for mac. So many things you take for granted on Windows when that's all you know. Things like a plethora of questions, balloons popping up everywhere and restarts for most software installations. They all drive Mac users to distraction.
But still, it served my purpose. My major need for Windows is checking if my website designs work in Internet Explorer. And as so often happens, I discover that my sites don't work in IE so back to the drawing board. Q make this process simple and has cost me nothing (as I already owned a copy of Windows XP).
Shortcomings and Bugs
The lack of a driver to support CD burning and any type of DVD access is an issue that needs to be addressed by the developer. To install from a DVD requires converting the DVD to an ISO. Use Disk Utility to make an DMG image of the DVD and then the command on this page at Tech-Recipes to convert that to an ISO.
On both Windows installations I encountered a crash on the first reboot of the installation process which required rebooting, but thereafter, had no further problems with the install, or since.
If you 'Save the state' of a Guest, when it restores it is hung, and needs restarting. I found this with both Windows and Linux (although I did not have this problem on my PowerBook G4). This is a bit of problem if you intend to use Windows regularly on an Intel Mac - although the boot up time is very fast.
And yes, Q does knock system performance around, especially if you up the memory of your Guest system.
Overall
Sure Q has some issues to resolve, but it is still in beta and it is free. From my experience, I sugges you give Q a look before you try Parallels if your looking for a virtualization solution on Intel Macs. If Q meets your needs, why would you bother paying for Parallels? And given Parallels is not even working on the latest Macs, it'd score a zero, while I'd give Q a 7.5/10.
HOW VIRTUALIZATION WORKS
Virtualization 101
Due to the limitations of x86 servers, many IT organizations must deploy multiple servers, each operating at a fraction of their capacity, to keep pace with today's high storage and processing demands. The result: huge inefficiencies and excessive operating costs.
Enter virtualization. Virtualization relies on software to simulate hardware functionality and create a virtual computer system. This enables IT organizations to run more than one virtual system – and multiple operating systems and applications – on a single server. The resulting benefits include economies of scale and greater efficiency.
Virtual Machines Explained
A virtual computer system is known as a 'virtual machine' (VM): a tightly isolated software container with an operating system and application inside. Each self-contained VM is completely independent. Putting multiple VMs on a single computer enables several operating systems and applications to run on just one physical server, or 'host.'
A thin layer of software called a 'hypervisor' decouples the virtual machines from the host and dynamically allocates computing resources to each virtual machine as needed.
Key Properties of Virtual Machines
VMs have the following characteristics, which offer several benefits.
Virtualization Macbook Pro
Partitioning
- Run multiple operating systems on one physical machine.
- Divide system resources between virtual machines.
Isolation
- Provide fault and security isolation at the hardware level.
- Preserve performance with advanced resource controls.
Encapsulation
- Save the entire state of a virtual machine to files.
- Move and copy virtual machines as easily as moving and copying files.
Hardware Independence
- Provision or migrate any virtual machine to any physical server.
