I also use a PerlRequire startup.pl to preload most modules (CGI, DBI),
but I thought that was only for quicker startup times and not for sharing
memory. Is that correct?
Preloading helps with speed (you don't get the the initial loading hit for
a module the first time it's used in a specific process) but it can also
help with memory on certain OSs.
Pre-loading *will* give you a longer startup time, as you have to pre-load
all the modules before apache can start.
However, as Michael says, the module would be loaded the first time a script
used it anyway - so you'd have the same delay but in the middle of a request
rather than at server start-up! Additionally you would have that delay in
each child process that apache creates in the entire life of the server.
Carl