While there isn't one included with the perl source distribution (yet) various folks have written packages that allow you to do at least some sort of profiling. The strategy usually includes modifying the perl debugger to handle profiling. Authors of these packages include
Wayne Thompson me@anywhere.EBay.Sun.COM Ray Lischner firstname.lastname@example.org Kresten Krab Thorup email@example.com
The original articles by these folks containing their profilers are available at ftp://convex.com/pub/perl/info/profiling.shar.
Recently, Dean Roehrich* has written a profiler for version 5 that likely will be distributed with the standard release. For now, it should be available through any of the extension archives as DProf.tar.gz.
Other resources at this site: