Overload Detecting in High Performance Network I/O Frameworks

Overload detecting mechanisms are the prerequisites for admission controls and differentiated services. Conventional mechanisms are always coordinated with conventional network stacks. As the hardware evolution and applications' increasing demand, the architecture of conventional network stacks make themselves become the bottleneck. In this context, high performance network I/O frameworks have been proposed and adopted by both academia and industry. However, the characteristics of these frameworks limit the effectiveness of conventional overload detecting mechanisms. In this paper, we propose that RX RING length can act as a good threshold signal to reflect whether overload happens or not. Through experiments with varying the input load and the processing task load, RX RING length is proved to be a high-quality indicator for overload detecting. Meanwhile, we design a low-cost algorithm to detect RX RING length in real time. Compared with the original method, our algorithm reduces more than 90% of running cost when RX RING is nearly full. This makes RX RING possible to be a high-quality indicator in future overload detecting mechanism design for applications based high performance network I/O frameworks.