use warnings;
use sort '_qsort';
use Benchmark qw(timethese);

my @x;
my $max = 40000;

$x[$_] = int rand(2e5) foreach (0..$max);
my @w = 1..$max;
my @z = reverse 1..$max;

sub sort_random {
	my @v = sort {$a <=> $b}  (@x);
}

sub sort_sorted {
	my @v = sort {$a <=> $b}  (@w);
}

sub sort_reversed {
	my @v = sort {$a <=> $b}  (@z);
}

timethese (800, {
	'random'  => \&sort_random,
	'sorted'  => \&sort_sorted,
	'reverse' => \&sort_reversed,
} );

##</code><code>##

$ perl bench_sort2.pl
Benchmark: timing 800 iterations of random, reverse, sorted...
    random: 14 wallclock secs (14.48 usr +  0.00 sys = 14.48 CPU) @ 55.26/s (n=800)
   reverse: 14 wallclock secs (13.57 usr +  0.00 sys = 13.57 CPU) @ 58.94/s (n=800)
    sorted: 14 wallclock secs (13.57 usr +  0.00 sys = 13.57 CPU) @ 58.94/s (n=800)

##</code><code>##

$ perl bench_sort2.pl
Benchmark: timing 800 iterations of random, reverse, sorted...
    random: 11 wallclock secs (11.31 usr +  0.00 sys = 11.31 CPU) @ 70.73/s (n=800)
   reverse:  2 wallclock secs ( 1.98 usr +  0.00 sys =  1.98 CPU) @ 403.84/s (n=800)
    sorted:  2 wallclock secs ( 1.94 usr +  0.00 sys =  1.94 CPU) @ 413.44/s (n=800)