As far as i understand, do modperl::Registryloader and apache::registryloader do the same job; They allow compilation of scripts at server startup.
ModPerl::RegistryCooker is used to create registry modules which emulate mod_cgi for Perl scripts.
See:
modperl::Registryloader ,
apache::registryloader and
ModPerl::RegistryCookerfor more info.
"We all agree on the necessity of compromise. We just can't agree on when it's necessary to compromise." - Larry Wall.