» It’s tough to scale, too: According to Blake Matheny, Tumblr’s Distributed Systems Engineer, the service’s broad distribution makes it different from many other social networks, adding complexity that can stress the servers greatly. “It’s not just one or two users that have millions of followers. The graph for Tumblr users has hundreds of followers,” he writes. “This is different than any other social network and is what makes Tumblr so challenging to scale.” Matheny says that people will go back hundreds of pages on the dashboard to read content. And the network will only grow in complexity over time — the site is growing by 30 percent each month, and requires hundreds of servers to do what it has to do. If you’re technically-inclined, read High Scalability’s entire article — it’s super-fascinating.