Web Server Technology Research Based On Zero-copy

With the development of modern communication technology, the Web System applied regions become wider and wider, and the scope and number of disseminating information are increasing exponentially. Web Server carrys more traffic load than ever before, as the key node of Web System releasing and processing information. Traditional Web Server, however, has performance bottlenecks in data transmission, throughput, and response speed aspects. Addressing these bottlenecks and improving Web Server performance is the most important thing for the Web System.Bandwidth, memory, and hard drive performance, CPU performance are not the main aspects any longer, which influence Web server performance, with the high-speed network link technology, software and hardware technology development. The key is information effective transmission from the host or other devices to the network layer. Therefore, this article solves the Web Server bottleneck problems in two different ways: speeding up packet send-receive rate and reducing data copy numbers in communication process .Its main job as follows:1. Research of the key technologies in improving Web Server performance. Adopting PF_RING technologies which similar to zero-copy, and Network Interface Card NAPI working mechanism can improve the packet send-receive rate effectively; DMA mode data copies can reduce CPU participation; MMAP mechanism can reduce memory copy, save system resources; The mended protocol stack, which analyzes packets in cross-layer and serial way from the link layer to the application layer, and transfers data pointers between layers directly, can avoid enqueue-dequeue operation and date copies between layers.2. A lightweight and high-performance Web Server prototype system which is named FastMattows is realized using the key technologies; PF_RING module, which is loaded in Linux kernel and combining the NIC NAPI mechanism, can quicken the packet capture speed in FastMattows system; The PF_RING Socket interface is modified to achieve coping data to PF_RING ring buffer in DMA mode and accessing data in MMAP way, so that the CPU participation and memory copies are reduced; FastMattows uses the mended protocol stack in splitting and packaging packet process. The mended protocol stack reduces data copies and enqueue-dequeue operation, quickens the packet processing speed. FastMattows's properties are analyzed and simulation experiments are carried out in the second part of the paper. After that, the article summaries the research work and points out the next work plan.To sum up, this paper researches how to resolve the Web Server performance bottlenecks and realizes a high-performance Web Server prototype system- FastMattows. It lays foundation for further research to improve strong practicality, feature-rich Web Server performance.