Improving Dynamic Web Servers by Affinity-Based Network Interfaces

Present trend towards multiprocessor and multi-core architectures as well as programmable NICs (Network Interface Cards) provides new opportunities to exploit the available parallelism in the network interface design and implementation to cope with the high communication overhead required to take advantage of a multi-gigabit links. In this paper we have used dynamic web servers to evaluate several alternatives to distribute the network interface work among the different cores available in the node. These alternatives have been devised according to the affinity of the work to be done with the location (proximity to the memories where the different data structures are stored) and characteristics of the processing core. Improvements in the throughput (up to 110%), the response time (up to 500%) and the requests attended per second (up to 85%) have been observed in our experiments on dynamic web servers.