I have been a little too obsessed with uber-performant things lately. I try to avoid as many CPU cycles, memory usage, I/O etc.
I have used Wordpress for many years but after I had done some heavy performance tests, it just seemed like a very inneficient architecture that every time any page is load all the plugins and thousands of lines of code get executed specially after seeing how in some benchmarks, PHP (not using HHVM) is very slow compared to Python or Ruby.
I stumbled upon Jekyll which turns templates into static HTML posts and to me it seemed wonderful as servers like NGINX are excellent at managing them without the I/O and processing time of FastCGI or uWSGI and the respective backend runtimes. For just HTML, this seemed to me like the most performant way to do my blog so I moved to Jekyll.
Check out the Jekyll docs for more info on how to get the most out of Jekyll.