Most Essential Tips for Improving Response Time of Your WordPress Blog
WordPress consumes enormous amounts of CPU and memory resources in order to respond to a single page request. The many string replacements in templates, multiple request to the database per request simply adds up and may take your entire site down if you hit the front page on fx. digg.com.
But worry not, because this brilliantly detailed article is there to help you optimize your page’s load time while also reducing the strain WordPress does to your server. A required read.