A Virtualization Metaphor

This is a rare kind of blog post for me, because I’m basically copying a discussion that rose from one of my Twitter/Facebook status updates earlier today:

I wish I could change the RAM, CPU configuration on running VMs in #VMWare and have the changes apply on next reboot.

This prompted one of my nieces, a lovely and intelligent young lady in high school, to ask me to say that in English.

I pondered just hand waving it, but I was loathe to do so. Like I said, she’s intelligent. I firmly believe that kids live up to your expectations; if you talk down to them and treat them like they’re dumb because that’s what you expect, they’re happy to be that way. On the other hand, if you expect them to be able to understand concepts with the proper explanations, even if they may not immediately grasp the fine points, I’ve found that kids are actually quite able to do so – better than many adults, truth be told.

So, this is my answer:

The physical machinery of computers is called hardware. The programs that run on them (Windows, games, etc.) is software.
VMware is software that allows you to create virtual machines. That is, instead of buying (for example) 10 computers to do different tasks and have most of them have unused memory and processor power, you buy one or two really beefy computers and run VMWare. That allows you to create a virtual machine in software, so those two computers become 10. I don’t have to buy quite as much hardware because each virtual machine only uses the resources it needs, leaving the rest for the other virtual machines.

However, one of the problems with VMWare currently is that if you find you’ve given a virtual machine too much memory or processor (or not enough), you have to shut it down, make the change, then start it back up. I want the software to be smart enough to take the change *now* and automatically apply it when it can, such as when the virtual machine is rebooting. For a physical computer, it makes sense — I have to power it down, crack the case open, put memory in, etc. — but for a virtual computer, it should be able to be done in software.

Think of it this way: hardware is like a closet. You can build a big closet or a small closet or a medium closet, but each closet holds a finite amount of stuff. Software is the stuff you put in the closet — clothes, shoes, linens, etc. You can dump a bunch of stuff into a big closet, but doing so makes it cluttered and hard to use. So if you use multiple smaller closets, you’re wasting space because you probably won’t fill every one exactly.

In this metaphor, virtualization is like a closet organizer system. You can add a clothing rod here to hang dresses and blouses on, and underneath that add a shelf or two for shoes, while to the side you have more shelves for pants and towels and other stuff. You waste a little bit of your closet space for the organizer, but you keep everything organized and clutter-free, which means you’re better off and take less time to keep everything up.

Of course, this metaphor fails on my original point, because it totally makes sense you have to take all the stuff off shelves before moving those shelves around. In the world of software, though, it doesn’t necessarily make sense — it’s just the right people didn’t think of it at the right time.

Clear?

I came close to busting out Visio and starting to diagram some of this. I decided not to.

Edit: I don’t have to diagram it! Thank you, Ikea, and your lovely KOMPLEMENT wardrobe organizer line!

Ikea KOMPLEMENT organizer as virtualization software

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