title: How to Measure a Web-Apps need for scalability
body: <p>I'm building a web app which will serve content to a constantly growing user base. I'm wondering where to start with scalability, and how to measure the performance of my app, so i know when it's needed.</p>
  
  <p>For example, I understand that as traffic to a site grows, things like minifying scripts and using caches for static content will help manage load times, but I'm not sure when the right time is to implement these features.</p>
  
  <p>Additionally, how can I measure the performance of the site, to know when it's time to start adding more servers,and building out the robustness of the app, etc - before my servers start crashing and choking?</p>
  
  <p>Thanks in advance...</p>