VM: A Disposable Computing Unit

The beauty of virtualization is in the disposable nature of the virtual machine.

Do you ever think that virtual machines (VMs) are disposable entities that you create and destroy on a whim? I do. I have the feeling that VMs are less valuable than their physical counterparts. I feel less guilt when rebooting a VM. I feel less angst when adding and removing hardware resources (NICs, disks, CPUs, memory). And, I feel a little buzzed when I get to remove one and free up some space for another semi-worthless VM to take its place.

Has virtualization made us think of virtual machines as throwaway commodities?

I think it has.

And, I think it has to do with how easy I can create a VM, bring it to life, put it into production and leave it in someone else's hands for routine care and feeding. Physical systems need nurturing, coaxing and special treatment.

Even a Gold disk image has to have some tweaking done to it in order to make it production-ready. You have to install drivers, setup disks, make sure that network drops are run, plug into power strips and trudge through the endless patch, reboot, patch, reboot cycle.

Physical systems gain value each time you install a driver, install a patch, configure a RAID controller or pop in additional RAM. But, you can create a VM from a template with a few mouse clicks, configure additional storage, change VLANs and you're up and running. What used to take all day on a physical system, now takes an hour at most for a VM.

There's your value difference between the two systems. Time.

VMs have reduced the cost of a reboot to a minute or less and a similarly configured physical machine can take 15 minutes or more for a reboot. No wonder I feel vindicated when I click the reboot button without so much as a flinch. It's virtual. What do I care?

Virtualization has trained me to think in terms of computing units and workloads, instead of actual systems. Workloads that have the shape and scent of an actual computer. VMs are more like photographs of actual systems or graphical representations of the real things.

Maybe it's just me.

Or, maybe that's the beauty of virtualization. Disposable, replaceable and volatile workloads that can spin up extra capacity on a moment's notice and then be mothballed or destroyed when the party's over. I rather like the idea of disposable computing units.

The term "computing unit" makes more sense in large scale deployments. A computing unit implies an amount of resources dedicated to a workload. Who cares about the number of VMs, operating system or other nonsensical details? What you're really looking for is horsepower to run a workload (application, database, service).

Thinking in computing units further drives the disposable nature of VMs. It also creates a whole new idea of which ingredients make up a VM but that's another story. In fact, it's tomorrow's story, "Wanted: A Virtual Machine OS."

What do you think of the disposable nature of VMs? Do you think that the term disposable is accurate when describing a VM? Talk back and let me know.