Yes, IIRC none of the running instances of my program had very large Shared parts in their memory usage. I won't be at this particular $client's till Wednesday but I'll double check then. (Thanks for the wiki tip; I will certainly update the FAQ there if my hypothesis is confirmed.)

The system is CentOS, but that doesn't have RPMs for any of the PAR utils (including PAR::Dist). Since PAR is meant to help with the bootstrapping problem of weakling perl installs, it'd be awesome if all major distros got one -- I'll see if what I can do in a couple of days :-)