in reply to Perl v5.6.1 looking for .pmc files
10 seconds to start up sounds about right if you have 150 modules you're loading and compiling also on modest hardware. Consider using Autoloader to load functions on demand instead of at startup to avoid some of that penalty. Also consider using Devel::DProf (run Perl with -d:DProf) and dprofpp to profile your code and see where perl is spending most of its time.
A 'stat' call is common if Perl is using 'stat' to look through @INC trying to search for your modules. A given module will rarely be found in the very first place perl looks, so you're going to get a lot of these failed calls.
Though I'm not really sure why it'd be looking for a .pmc and not .pm. I haven't heard anything about that. But still, as another poster mentioned, these calls should take almost no time whatsoever. I doubt these calls (failing or otherwise) are what's causing your performance woes.