Adaptive OS Switching for Improving Availability During Web Traffic Surges: A Feasibility Study

Web services have seen early adoption and rapid growth with the introduction of various web system frameworks, and not only large companies but also smaller businesses or individuals can provide their own web services offering access to their products, entertainment, and information. Therefore, as the number of Internet users increases, especially with the spread of smartphones, even relatively small web service infrastructure need to have both high access performance and availability, although the cost of additional computational resources and redundant servers may be hard to bear depending on the load. We focus on the fact that the performance characteristics may differ depending on the internal implementation of the operating system (OS), even when the available computing resources are the same. This paper investigates the possibility of developing a system that achieves both high access performance and availability of the web server by dynamically switching the OS on which the web server is running, without requiring additional computing resources or using redundant servers. This paper identifies the differences between Linux and FreeBSD in terms of network processing and describes the mechanism of process migration among heterogeneous OSes to switch the OSes. It then demonstrates the feasibility of our approach with experimental results on the performance characteristics and load tolerance of a web server in operation when the OSes are dynamically switched.