Devel::NYTProf is a powerful feature-rich perl source code profiler. * Performs per-line statement profiling for fine detail * Performs per-subroutine statement profiling for overview * Performs per-block statement profiling (the first profiler to do so) * Accounts correctly for time spent after calls return * Performs inclusive and exclusive timing of subroutines * Subroutine times are per calling location (a powerful feature) * Can profile compile-time activity, just run-time, or just END time * Uses novel techniques for efficient profiling * Sub-microsecond (100ns) resolution on systems with clock_gettime() * Very fast - the fastest statement and subroutine profilers for perl * Handles applications that fork, with no performance cost * Immune from noise caused by profiling overheads and I/O * Program being profiled can stop/start the profiler * Generates richly annotated and cross-linked html reports * Trivial to use with mod_perl - add one line to httpd.conf * Includes an extensive test suite * Tested on very large codebases