A good and scalable architecture always matters
Dynamic web sites often evolve from a simple and not necessarily efficient proof-of-concept to a larger system that needs to serve many customers. Getting dynamic web sites to scale is not always easy and HTTP is rarely the culprit. In a very interesting talk, Willy Tarreau, the author of HA Proxy explores several of these factors with a simple use case.
The interesting part of this presentation is that it combines both performance, measured in number of users served per second, with energy consumption. Increasing the number of servers does not always increase the performance proportionally while the energy consumption increase. This presentation could be a good topic for discussions with students to ask them to predict what would happen with each proposed modification and try to understand the bottlenecks in this configuration.