> Can someone let me know which one is correct so I can stop worrying
> about it?
ns_include_adp will stat the file on every request. If ADP caching is
enabled, and the ADP is in the cache, and the file on disk hasn't
changed since the ADP was cached, then ns_adp_include will use the
cached version of the ADP. Otherwise it will load the ADP from disk.
(Maybe not really from disk; the kernel might have the file contents in
its cache.)
Search for "ADP Tuning" at <http://aolserver.com/docs/config.adp> to see
how to enable the cache.