You can probably get it to work under PerlRun. That would completely eliminate the startup time. It won't help with the processing time though. For that, you really have to profile things and change code. The only generic piece of advice I can offer is to run perl 5.6.1 compiled with no threads, since it seems to have better performance than later perl versions.

Incidentally, FastCGI and SpeedyCGI have the same limitations as mod_perl when running poorly written code. PerlRun does a better job than either of them do at trying to make things work.