Let's see if I understand this right: you want to determine how powerful your server(s) need to be
before starting to write your program?
If I had to make such a decision, I'd probably ask myself the following questions:
- What features does the program need? Heavy database applications can require lots of RAM/CPU.
- How many users do you expect to serve? Do you want to create a second Slashdot?
- What's the penalty for not serving your customers fast enough? Are they willing to wait, or is your application so mission-critical that you must acknowledge the request within a specified amount of time?
Based upon these (and perhaps more?) questions, I could deside what amount of servers I would need. Or at least, I could take this into account when designing my application!
Those few applications I've developed didn't require more than one server to give a reasonable response-time...
Hope this helps! Greets,
-- JaWi
"A chicken is an egg's way of producing more eggs."