I wrote a rather small skeleton for my web apps and thought that I would also add a small cache for it. It is rather simple: If the current page exists as a file in the cache and the file isn't too old, read it out and exit instead of rebuilding the page If the current page isn't cached/outdated recalc the page and save it However, the bad thing about it is: My performance tests with a page that receives 40 relatively long posts via a MySQL query said that with using the cache, it took even longer to handle a single request (1000 tests each) How can that happen? Should I just remove the complete raw-PHP cache and relieve on the availability of some PHP cache like memcached or so?