Performance evaluation of HTTP web servers in embedded systems

Abstract: This Masters Thesis was carried out in cooperation with Syntronic AB. The purpose was todetermine what was possible in terms of Hypertext Transfer Protocol (HTTP) serverperformance on selected hardware platforms for embedded systems. The results should bevaluable for those who are about to select a hardware platform for an embedded system thatwill contain a HTTP server, and the evaluation therefore included load limits, performancecharacteristics and system resource usage.The required data was gathered with performance measurements, and a pre-study wasperformed to decide on platforms, functionality and performance parameters to include in thestudy. Three hardware platforms with different levels of performance - BeagleBoard-xM,STK1000 and Syntronic Midrange - were selected. A simulated web application was usedduring the tests and a total of five HTTP server software were tested.BeagleBoard-xM with BusyBox httpd had the best overall performance when running the testapplication. It had a high overload point, low connection durations when not overloaded, anda superior overload behavior. However, Midrange with a modified version of a server madeby Stefano Oliveri performed better when not overloaded. STK1000 was far behind the othertwo platforms in terms of performance.The overload behavior and efficiency of system resource usage differed greatly between theservers. The test results also showed that the performance varied significantly betweenHTTP server software running on the same hardware platform, and generally the softwarewith limited feature sets performed best.