Every company as they start getting traction faces challenges about scaling databases, scaling website/applications, etc. I would like to ask HN about what was your scalability approach? When building minimum viable product release, did you built it with scalable architecture in mind or rebuild the site ground up once it got more traction?
Scaling to a million page views or so a day is not difficult. With the technologies available at hand there is less need for big hardware to do it. For instance you could grab a few Amazon EC2 nodes, use one as a balancer to the others. Grab nginx for the web server, proxy to your application, varnish for static caching. Alot is going to be determined by the way you access the database, there is no need to go to nosql when mysql can scale beyond your needs. Limit your queries, only select the data you need instead, use indexes, be smart about table structures.<p>If you ever do get to facebook/twitter like traffic, you'll probably have money and entire ops team to deal with it.
Scale is almost always something you should ignore completely while building an MVP. It is trivial to build a web app that can handle enough users to prove the product. There are exceptions, but they're very rare.
What happens when site pickup and scaling issue becomes real. How would you deal with such situations? Do you rewrite the site or try to keep scaling up as much as possible.