@carlzulauf:

Good point! This article was supposed to be an intro to the main steps towards memory optimisation but I guess I could profile individual kernel modules as well and update the article with the findings. I'll get some time to do it.

Other aspects of memory consumption that I was thinking of are mainly around common services on Ubuntu servers. For example using Nginx instead of Apache to lower the memory footprint, however these would be specific to individual use cases. (Not everybody is using a HTTP server, although it's quite common).