There is no difference ;) 
#!/usr/bin/perl --

use strict;
use warnings;

use Benchmark qw' cmpthese ';

BEGIN { *begin = sub {} }

INIT { *init = sub {} }

sub declared {}

*runtime = sub {};

cmpthese(-3, {
    begin      => sub { begin()    for (1 .. 1000) },
    init       => sub { init()     for (1 .. 1000) },
    declared   => sub { declared() for (1 .. 1000) },
    runtime    => sub { runtime()  for (1 .. 1000) }
});
__END__

[download]
$ perl temp.pl
           Rate declared     init  runtime    begin
declared 1663/s       --      -0%      -3%      -6%
init     1670/s       0%       --      -3%      -6%
runtime  1722/s       4%       3%       --      -3%
begin    1772/s       7%       6%       3%       --

$ perl temp.pl
           Rate    begin     init  runtime declared
begin    1607/s       --      -1%      -1%      -9%
init     1621/s       1%       --      -1%      -8%
runtime  1630/s       1%       1%       --      -8%
declared 1770/s      10%       9%       9%       --

$ perl temp.pl
           Rate declared  runtime    begin     init
declared 1622/s       --      -2%      -3%      -4%
runtime  1655/s       2%       --      -1%      -2%
begin    1668/s       3%       1%       --      -1%
init     1686/s       4%       2%       1%       --

$ perl temp.pl
           Rate  runtime     init    begin declared
runtime  1551/s       --      -6%      -7%     -11%
init     1658/s       7%       --      -0%      -5%
begin    1661/s       7%       0%       --      -4%
declared 1737/s      12%       5%       5%       --

[download]

In reply to Re: Subs created at run-time are faster than those created at compile-time by Anonymous Monk
in thread Subs created at run-time are faster than those created at compile-time by neodon

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