High Scalability regularly profiles the scalability challenges of some of the web's busiest sites. Today HS provides a closer look at the architecture behind architecture behind Tumblr, the popular instablogging service that has grown to 15 billion page views per month.
"Tumblr started as a fairly typical large LAMP application," High Scalability writes. "The direction they are moving in now is towards a distributed services model built around Scala, HBase, Redis, Kafka, Finagle, and an intriguing cell based architecture for powering their Dashboard. Effort is now going into fixing short term problems in their PHP application, pulling things out, and doing it right using services."
An interesting data point: Tumblr currently runs its entire operation out of a single colocation facility. Read more at High Scalability.