Does it scale? Who cares (2011)
Couldn't agree with this article more.I built the biggest social network to come out of India from 2006-2009. It was like Twitter but over text messaging. At it's peak it had 50M+ users and sent 1B+ text messages in a day.When I started, the app was on a single machine. I didn't know a lot about databases and scaling. Didn't even know what database indexes are and what are their benefits.Just built the basic product over a weekend and launched. Timeline after that whenever the web server exhausted all the JVM threads trying to serve requests:1. 1 month - 20k users - learnt about indexes and created indexes.2. 3 months - 500k users - Realized MyISAM is a bad fit for mutable tables. Converted the tables to InnoDB. Increased number of JVM threads to tomcat3. 9 months - 5M users - Realized that the default MySQL config is for a desktop and allocates just 64MB RAM to the database. Setup the mysql configs. 2 application servers now.4. 18 months - 15M users - Tuned MySQL even more. Optimized JDBC connector to cache MySQL prepared statements.5. 36 months - 45M users - Split database by having different tables on different machines.I had no idea or previous experience about any of these issues. However I always had enough notice to fix issues. Worked really hard, learnt along the way and was always able to find a way to scale the service.I know of absolutely no service which failed because it couldn't scale. First focus on building what people love. If people love your product, they will put up with the growing pains (e.g. Twitter used to be down a lot!).Because of my previous experience, I can now build and launch a highly scalable service at launch. However the reason I do this is that it is faster for me to do it - not because I am building it for scale.Launch as soon as you can. Iterate as fast as you can. Time is the only currency you have which can't be earned and only spent. Spend it wisely.Edited: formatting