Stream Engine: A New Kernel Interface for High-Performance Internet Streaming Servers

As high-speed Internet connections and Internet streaming media become widespread, the demand for high-performance, cheap Internet streaming servers increases. This paper looks into the performance limitations of streaming server applications running on PC servers with Linux, and proposes a new kernel optimization called "Stream engine" that combines both copy elimination and context switch avoidance to double the streaming server throughput. The experiments with stream engine show that for Internet streaming, eliminating context switches is just as important as eliminating data copying. Using profile data, the paper also project the benefits of TCP offloading hardware implementing part or all of the stream engine optimization.