in reply to Becoming familiar with a too-big codebase?
Devel::Trace usually does the trick for me.
When it doesn't, I open up Devel::TraceCalls and GraphViz::ISA.
If dealing with apache, I use Apache::Status.
Devel::ModInfo (and the tools it comes with) might also be useful (though I've not used them).
There are also useful B:: modules like B::Xref, but but they're more useful for developing tools like the forementioned modules (which might be what you're after).
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