Can someone show me a test that will prove that passing
references to a subroutine is better/faster than passing
around the data itself? I haven't hit upon a good test
that shows passing references is faster. 
use strict;
use Benchmark;

my $len = 4000;
my @data = ();
push(@data,rand()) for (0..$len);

timethese(2000, {
    'by_whole' => sub {
        my @copy = sort_by_array(@data);
    }
    ,
    'by_refs' => sub {
        my @copy = sort_by_ref(\@data);
    }

});

sub sort_by_array
{
    return sort {$a <=> $b} @_;
}

sub sort_by_ref
{
    return sort {$a <=> $b} @{$_[0]};
}

__END__


Benchmark: timing 2000 iterations of by_refs, by_whole...
by_refs: 54 wallclock secs (42.80 usr +  0.01 sys = 42.81 CPU) @ 46.72
+/s (n=2000)
by_whole: 44 wallclock secs (43.02 usr +  0.00 sys = 43.02 CPU) @ 46.4
+9/s (n=2000)

[download]

In reply to Show that using references is faster by Keystroke

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.