suggestions for dynamic run-time configuration?

I was wondering if anyone had suggestions / recommendations for a
run-time application configuration mechanism for mod-perl apps. What I
am thinking of is simply a way to communicate new application settings
to all of the mod-perl children.

The only solution I can think of is to have all of the mod-perl child
processes periodically check a file to see if it has changed, and if
so have the child process reload their application configuration. By
"application configuration" I mean configuration data at the
application level and above - not necessarily httpd-level
configuration data (i.e. such as found in httpd.conf.) Typical
application configuration data includes database credentials, flags to
enable/disable parts of the application, urls for web services used by
the application, etc. The idea is to have a capability something like
Facebook's Gatekeeper as described in one of their tech talks (
http://techcrunch.com/2011/05/30/facebook-source-code/ )

To reduce the impact this checking would have on serving requests I
was thinking of checking only every N requests (i.e. N = 10) and/or
performing the check as part of the cleanup handler.

Any suggestions / recommendations or alternatives for a mod-perl environment?