The current release of P::D requires Perl-5.10 via "use" syntax in the modules and tests. This module is intended for systems with a working fork. If your system's fork is broken then it will not work, or -- worse yet -- work sporadically. Adjusting the parameters in the expensive tests (see next paragraph) will help determine just how much abuse your system can handle. A number of items in t/*t are intended to stress- test the module. They stress-test your system at the same time: creating over 100_000 status files or forking hundreds of jobs in a short period. All of the really dangerous tests will short-circut unless EXPENSIVE_TESTS is set in the environment -- for example "EXPENSIVE_TESTS=1 prove --blib t/*t" will run everything. All of ./Profile/*t (currently empty) are intended for use with Devel::Profile. For example: perl -d:Profile --blib Profile/phorkatosis; They are separated in order to avoid adding Devel::Profile to the Manifest for the small number of cases where anyone cares. Those of us who do this kind of profiling will already have D::P installed and won't care; everyone else can ignore them.