You could try this 
#!/usr/bin/perl --

use strict;
use warnings;

use Benchmark 'cmpthese';

{
    my $small = join'', map { ' ' x  (int rand 2) . ','.  (int rand 2)
+.$_ } 0 .. 1_000;
    cmpthese(-3,{
        'small1' => sub { my $f = $small; $f =~ s/\s+,\s+|\s+,|,\s+/,/
+g; },
        'small2' => sub { my $f = $small; $f =~ s/\s*,\s*/,/g; },
    });
    undef $small;
}
print "\n";
{
# 1_000_000 was too much for my machine
    my $bigg = join'', map { ' ' x  (int rand 2) . ','.  (int rand 2).
+$_ } 0 .. 200_000;

    cmpthese(-3,{
        'bigg1' => sub { my $f = $bigg; $f =~ s/\s+,\s+|\s+,|,\s+/,/g;
+ },
        'bigg2' => sub { my $f = $bigg; $f =~ s/\s*,\s*/,/g; },
    });
    undef $bigg;

}
__END__
perl 5.10.1

         Rate small1 small2
small1  365/s     --   -69%
small2 1171/s   221%     --

        Rate bigg1 bigg2
bigg1 1.27/s    --  -77%
bigg2 5.41/s  327%    --


perl 5.8.8

         Rate small1 small2
small1  785/s     --   -51%
small2 1587/s   102%     --

        Rate bigg1 bigg2
bigg1 2.59/s    --  -62%
bigg2 6.86/s  165%    --

[download]

In reply to Re: Comparing Regular Expressions by Anonymous Monk
in thread Comparing Regular Expressions by vitoco

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.