$perl -d:MOD script.pl runs the program under the control of a debugging, profiling, or tracing module installed as Devel::MOD.
For example, -d:NYTProf executes the program using the Devel::NYTProf profiler.
See all available Devel modules here
Recommended modules:
Devel::NYTProf -- Powerful fast feature-rich Perl source code profilerDevel::Trepan -- A modular gdb-like Perl debuggerDevel::MAT -- Perl Memory Analysis ToolDevel::hdb -- Perl debugger as a web page and REST serviceDevel::DebugHooks::KillPrint -- Allows to forget about debugging by print statementDevel::REPL -- A modern perl interactive shellDevel::Cover -- Code coverage metrics for Perl