Absurd precision

In the battlefield, facing the enemy army, the general ask his aide-de-camp:
- How many soldiers do you think there are in the enemy ranks?
The aide looks for a little while and respond:
- One thousand and three, my general.
- Amazing! How can you tell this precise number so quickly?
- Very easy, my general! There are three in the first line, and about one thousand behind.
I like this joke a lot. And I think it teaches a lot, in a very simple and humorous manner. Performance is about measuring, calculating and quantifying. The values must be presented with the right precision, but no more. Otherwise, you are inventing.

I doubt you could report  67.953% usage average, but 68%.  Or, perhaps even better, between 65% and 70%. You cannot arbitrarily add (absurd) precision. I'm not trying to teach error theory here. Only warning you to be careful when giving quantities.

Demystifying Virtual Capacity, 2nd Part and Tool

Hello:
Here are a new document and tool about virtual capacity: "Demystifying Virtual Capacity, Part II".

Abstract: The previous work, “Demystifying Virtual Capacity, Part I” is extended here to more that 2 virtual machines (VM). For solving the virtual capacity it has been created a companion spreadsheet helper: “The Virtual Capacity Demystifyier”. This tool is presented here, and its usage is illustrated with several simple use cases.

Section I: The VM Capacity Space. In this part the guidelines for solving the generic N virtual machines capacity problem are exposed.

Section II: The Dashboard. The user interface of the spreadsheet helper is presented. The inputs and the outputs are conveniently explained.

Section III: Scenarios. This is time to play with the tool. Several simple scenarios are presented, but the main purpose of this section is to show how to use the tool by example.

I hope you like it! Please, send me feedback as I would like to improve the tool in the future, as time permits...
Jorge L. Navarro