#! perl -sw
use vars '$size $cpu';
use strict;
use Benchmark 'cmpthese';

$::size ||= 1000;
$::cpu  ||= 1;

my @empty;
my @prealloc; $#prealloc = $::size;

cmpthese( -$::cpu, {
	push		=> 'push @empty,                 q{data} for 0 .. $::size-1',
	assign	  => '$empty[$_] =                 q{data} for 0 .. $::size-1',
	assignpre   => '$prealloc[$_] =              q{data} for 0 .. $::size-1',
	slice	   => '@empty[0 .. $::size-1] =    (q{data} x $::size)',
	slicepre	=> '@prealloc[0 .. $::size-1] = (q{data} x $::size)',
});

cmpthese( -1, {
	push		=> 'push @empty,                     rand $::size for 0 .. $::size-1',
	assign	  => '$empty[$_] =                     rand $::size for 0 .. $::size-1',
	assignpre   => '$prealloc[$_] =                  rand $::size for 0 .. $::size-1',
	slice	   => '@empty[0 .. $::size-1] =    (map{rand $::size}1 .. $::size)',
	slicepre	=> '@prealloc[0 .. $::size-1] = (map{rand $::size}1..$::size)',
});

__END__
C:\test>arraybench -size=10000 -cpu=1
Benchmark: running assign, assignpre, push, slice, slicepre, each for at least 1 CPU seconds...
    assign:  2 wallclock secs ( 1.01 usr +  0.00 sys =  1.01 CPU) @ 18.77/s (n=19)
 assignpre:  1 wallclock secs ( 1.01 usr +  0.00 sys =  1.01 CPU) @ 18.77/s (n=19)
      push:  1 wallclock secs ( 1.05 usr +  0.05 sys =  1.10 CPU) @ 13.61/s (n=15)
     slice:  2 wallclock secs ( 1.10 usr +  0.00 sys =  1.10 CPU) @ 26.32/s (n=29)
  slicepre:  1 wallclock secs ( 1.15 usr +  0.00 sys =  1.15 CPU) @ 26.04/s (n=30)
            Rate      push    assign assignpre  slicepre     slice
push      13.6/s        --      -28%      -28%      -48%      -48%
assign    18.8/s       38%        --       -0%      -28%      -29%
assignpre 18.8/s       38%        0%        --      -28%      -29%
slicepre  26.0/s       91%       39%       39%        --       -1%
slice     26.3/s       93%       40%       40%        1%        --
Benchmark: running assign, assignpre, push, slice, slicepre, each for at least 1 CPU seconds...
    assign:  1 wallclock secs ( 1.06 usr +  0.00 sys =  1.06 CPU) @ 20.74/s (n=22)
 assignpre:  1 wallclock secs ( 1.15 usr +  0.00 sys =  1.15 CPU) @ 20.85/s (n=24)
      push:  1 wallclock secs ( 0.98 usr +  0.03 sys =  1.01 CPU) @ 15.83/s (n=16)
     slice:  1 wallclock secs ( 1.00 usr +  0.00 sys =  1.00 CPU) @  6.99/s (n=7)
  slicepre:  1 wallclock secs ( 1.13 usr +  0.00 sys =  1.13 CPU) @  7.07/s (n=8)
            Rate     slice  slicepre      push    assign assignpre
slice     6.99/s        --       -1%      -56%      -66%      -66%
slicepre  7.07/s        1%        --      -55%      -66%      -66%
push      15.8/s      127%      124%        --      -24%      -24%
assign    20.7/s      197%      193%       31%        --       -1%
assignpre 20.9/s      198%      195%       32%        1%        --

C:\test>