Here's a question I posted to the DBI as well as mod_perl mailing list that I thought would be also a good question to ask here:
I'm currently working on... of all things, a book on book about web app programming with Perl/Apache/MySQL, and I'm trying to explain what Ubuntu packages to use for installation (and I'm sure other Linux variants same applies)
I've used both prefork and worker (as of late, due to concerns with perl and threads), both of which seem to work fine. Though, the DBI documentation warns of caveats of using threaded, especially if the client is not thread safe (I always compile mysql with a thread-safe client, and DBD::mysql against that thread safe client).
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