Efficient resource management on template-based web servers

The most commonly used request processing model in multithreaded web servers is thread-per-request, in which an individual thread is bound to serve each web request. However, with the prevalence of using template techniques for generating dynamic contents in modern web servers, this conventional request processing model lags behind and cannot provide efficient resource management support for template-based web applications. More precisely, although content code and presentation code of a template-based dynamic web page can be separated into different files, they are still processed by the same thread. As a result, web server resources, especially database connection resources, cannot be efficiently shared and utilized. In this paper, we propose a new request scheduling method, in which a single web request is served by different threads in multiple thread pools for parsing request headers, performing database queries, and rendering templates. The proposed scheme ensures the high utilization of the precious database connections, while templates are being rendered or static contents are being served. We implemented the proposed scheme in CherryPy, a representative template-enabled multithreaded web server, and we evaluated its performance using the standard TPC-W benchmark implemented with the Django web templates. Our evaluation demonstrates that the proposed scheme reduces the average response times of most web pages by two orders of magnitude and increases the overall web server throughput by 31.3% under heavy loads.