I've had similar problems on my 1.something GHz machine, its entirely plausible. In that case it was a really large chunk of data from Data::Dumper. I switched to Storable and that was much faster.
Comment on Re: Re: Saving parsed perl for faster loading?
Storable was what I was thinking of too when I read the question. I use it for most configuration style things now, with auto-update if the configuration file changes. In some cases it has only a marginal benefit, but for 8000+ regexes it might be worth doing.