gistfile1.txt

#!/usr/bin/perl

use strict;
use warnings;

use File::Copy;
use Benchmark qw(cmpthese);

my $file = shift;
my $moved = "$file.mv";

cmpthese shift || -3, {
    mv          => sub {
        system "mv" => $file => $moved;
        die if $?;
        system "mv" => $moved => $file;
        die if $?;
    },
    move        => sub {
        move $file, $moved or die $!;
        move $moved, $file or die $!;
    },
    rename      => sub {
        rename $file, $moved or die $!;
        rename $moved, $file or die $!;
    },
    cp          => sub {
        system "cp" => $file => $moved;
        die if $?;
        system "cp" => $moved => $file;
        die if $?;
    },
    copy        => sub {
        copy $file, $moved or die $!;
        copy $moved, $file or die $!;
    },
};

__END__

For a small file (3 lines of text)
         Rate     cp     mv   copy   move rename
cp     68.1/s     --    -2%   -95%   -99%   -99%
mv     69.6/s     2%     --   -95%   -99%   -99%
copy   1282/s  1782%  1741%     --   -74%   -82%
move   5000/s  7240%  7080%   290%     --   -30%
rename 7143/s 10386% 10157%   457%    43%     --


For a large file (2.4 megs /usr/share/dict/words)
         Rate     cp     mv   copy   move rename
cp     36.0/s     --   -48%   -49%   -99%   -99%
mv     69.6/s    93%     --    -1%   -99%   -99%
copy   70.6/s    96%     1%     --   -99%   -99%
move   5000/s 13780%  7080%  6980%     --   -30%
rename 7143/s 19729% 10157% 10014%    43%     --