Anyone who ever performs profiling of a Zend Framework application will
immediately recognize that class loading is relatively expensive in Zend
Framework. Between the sheer number of class files that need to be
loaded for many components, to the use of plugins that do not have a 1:1
relationship between their class name and the file system, the various
require_once() can be problematic. This chapter intends to provide
some concrete solutions to these issues.