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After I’ve complained on #perl channel that dprofpp (perl profiler) dies on me, I received a number of suggestions on how to profile the code without using dprofpp. Ideas ranged from elemetary insertion of ‘print “Started”, time,”\n”‘ to all sorts of dynamic subroutine overloading. Here is one elegant solution that was suggested:

sub foo { print "foo (@_)\n" }
sub bar { print "bar (@_)\n" }

for (qw(foo bar)) {
  my $name = "main::" . $_;
  my $old = *$name{CODE};
  *$name = sub {
    print scalar(localtime), " Started $name\n";
    &$old;
    print scalar(localtime), " Finished $name\n";
  };
}

foo(qw(one two));
bar(qw(three four));

Oh, and someone also mentioned that dprofpp is known to be buggy. Here is a quote from the “Profiling Perl” article at perl.com:

The other problem you might face is that Devel::DProf, being somewhat venerable, occasionally has problems keeping up on certain recent Perls, (particularly the 5.6.x series) and may end up segfaulting all over the place.

Tag: profile

Lucas Zarebinski – still life photographer

Profiling perl