The Zend Optimizer has been integrated into PHP core with the 5.5 release, which, according to the RFC page, has many advantages over APC.
The request causes Dispatcher to eventually refresh the file in the cache as new content is published.
Cache invalidation requests for a page are also generated for any aliases or vanity URLs that are configured in the page properties.
The dummy file thing is honestly more of a workaround than a solution, but you can create a file, and put a single line fpm cycle (instead of spawning a separate process), and it will be executed by the process that we need.
Cache invalidation is a process in a computer system whereby entries in a cache are replaced or removed.
The servlet uses the values to construct the HTTP request for Dispatcher.
When the servlet is deployed to the publish instance, the following URL causes Dispatcher to delete the /content/geometrixx-outdoors/page and then cache a new copy.
A graceful restart (sending SIGHUP to it) is enough for the cache to clear.
According to a guy in the #php channel on freenode, this is the recommended way to do it.
Issue an HTTP request that causes Dispatcher to delete cached files, and immediately retrieve and recache the file.