Beefy Boxes and Bandwidth Generously Provided by pair Networks
Don't ask to ask, just ask

How do I profile my Perl programs?

by faq_monk (Initiate)
on Oct 08, 1999 at 00:12 UTC ( #525=perlfaq nodetype: print w/ replies, xml ) Need Help??

Current Perl documentation can be found at

Here is our local, out-dated (pre-5.6) version:

You should get the Devel::DProf module from CPAN, and also use from the standard distribution. Benchmark lets you time specific portions of your code, while Devel::DProf gives detailed breakdowns of where your code spends its time.

Here's a sample use of Benchmark:

  use Benchmark;

  @junk = `cat /etc/motd`;
  $count = 10_000;

  timethese($count, {
            'map' => sub { my @a = @junk;
                           map { s/a/b/ } @a;
                           return @a
            'for' => sub { my @a = @junk;
                           local $_;
                           for (@a) { s/a/b/ };
                           return @a },

This is what it prints (on one machine--your results will be dependent on your hardware, operating system, and the load on your machine):

  Benchmark: timing 10000 iterations of for, map...
         for:  4 secs ( 3.97 usr  0.01 sys =  3.98 cpu)
         map:  6 secs ( 4.97 usr  0.00 sys =  4.97 cpu)

Log In?

What's my password?
Create A New User
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others wandering the Monastery: (11)
As of 2015-11-30 18:15 GMT
Find Nodes?
    Voting Booth?

    What would be the most significant thing to happen if a rope (or wire) tied the Earth and the Moon together?

    Results (778 votes), past polls