SharePoint’s Page Output Caching can offer a massive performance boost to publishing sites but only when its working and working correctly. One of the problems I have seen is when some administrators turn on Page Output Caching they just assume it works. While this may be the desire and in most cases it may just work for you I would suggest you verify; and I don’t mean hit the site with the browser to see if it speeds up.
This post is about troubleshooting SharePoint’s Page Output Caching. Now if you don’t use Page Output Caching or yours is working just fine you are the ‘Master of your Page Output Caching’ as for the rest of us we will likely need to put on our troubleshooting hat and dig a bit deeper. I find troubleshooting anything is allot easier if you know a little about how the component you are troubleshooting operates and how it is suppose to work.