Current Massively Multi-player Online Games (MMOGs) have enormous server-side bandwidth requirements. The costs of providing this bandwidth is in turn passed on to the consumer in the form of high monthly subscription fees. Prior work has primarily focused on distributing this bandwidth using peer-to-peer architectures, but these architectures have difficulty preventing cheating, overwhelming low resource peers, and maintaining consistent game state. We have developed a hybrid game architecture that combines client-server and peer-to-peer technologies to prevent cheating, maintain centralized and consistent game state, significantly reduce central server bandwidth, and prevent lower capacity players from being overwhelmed. By dramatically reducing the bandwidth needed to host a game without introducing additional liabilities, our hybrid architecture reduces the costs associated with that bandwidth and allows MMOG developers to reduce the cost of monthly subscription fees. In addition, because the central server will need less bandwidth per player, a single server is able to support considerably more concurrent players. Our experiments show that bandwidth can be reduced by up to 95% and a single server can support a game twice as large.

Game engines process a lot of data under strict deadlines. Therefore, measures to increase performance are important in this area. Data-Oriented Design (DOD) promotes principles that are meant to increase performance by better cache utilization. The purpose of this thesis is to examine a selection of these principles to give a better understanding of how DOD affects CPU time and the rate of cache misses, with focus on the area of game development. More specifically, the principles examined are removal of run-time polymorphism, iteration over contiguous data, and lowering the amount of data in hot loops. Also, the Entity-Component-System pattern is examined, which is based upon DOD principles. The approach was to first present a theoretical background on the subject, and then to conduct tests by implementing a simulation of movement and collision detection utilizing said principles. The tests were written in C++ and executed on an Intel Core i7 4770k with no rendering. CPU time was measured in updated entities per μs, and cache utilization was measured in the form of cache miss rate. The results showed that the DOD principles did increase performance. Cache miss rate was also lower, with the exception of when removing run-time polymorphism. The conclusion is that Data-Oriented Design, used in game development, is likely to result in better performance, mostly as a result of better cache utilization.