What are we talking about exactly, what and what about it specifically needs to scale in what way?<p>Does it need to process more things per time?<p>Does it need to run on more machines?<p>Is it time critical / is responsiveness critical?<p>What are it's bottlenecks? Is it mem-bound? CPU-bound? IO-bound?<p>What is "it"?<p>Is "it" connecting to something else, and what does "something" run on?