Playing games with databases

Scalability is a fundamental problem in the development of computer games and massively multiplayer online games (MMOs). Players always demand more - more polygons, more physics particles, more interesting AI behavior, more monsters, more simultaneous players and interactions, and larger virtual worlds. Scalability has long been a focus of the database research community. However, the games community has done little to exploit database research. Most game developers think of databases as persistence solutions, designed to store and read game state. But the advantages of database systems go way beyond persistence. Database research has dealt with the beautiful question of efficiently processing declarative languages, and the resulting research questions have touched many areas of computer science. In this talk, I will show how the idea of declarative processing from databases can be applied to computer games and simulations. I will describe our journey from declarative to imperative scripting languages for computer games and simulations, introducing the state-effect pattern, a design pattern that enables developers to design games and simulations that can be programmed imperatively, but processed declaratively. I will then show how we can use database techniques to run scalable games and simulations cheaply in the cloud. I will then discuss how we can use ideas from optimistic concurrency control to scale interactions between players in MMOs, and I will describe how we can use these techniques to build elastic transaction processing infrastructure for the cloud.