Programming Perl, 4th Edition

Devel::NYTProf

The Devel::NYTProf module started at the New York Times by Adam Kaplan, although it’s currently maintained outside the Times now. It’s fast (written in C), it’s powerful, and it makes nice reports. It’s the fastest statement and subroutine profiler available, and we don’t have enough room to tell you all of the wonderful things about it. Download it from CPAN, and then use it just like the other debuggers:

% perl –d:NYTProf your_program

Once finished, you can inspect the results as HTML files. The first HTML file (Figure 18-1) is the summary:

% nytprofhtml ––open

Figure 18-1. The starting page for the HTML view of NYTProf

You can set various options in the NYTPROF environment variable. For instance, you can tell the profiler when to start: right away, at the INIT phase, or at the beginning of the END:

% env NYTPROF=start=init perl –d:NYTProf your_program

See the module documentation for more details. Now go take that coffee break. You’ll need it for the next chapter.