<?php
class A {
    public $a;

    public function set($a) {
        $this->a = $a;
    }

    public function bind(&$a) {
        $this->a = &$a;
    }
}

$i = $m1 = $m2 = 0;

echo "start: ", xdebug_memory_usage(), "\n";

$a = new A();
for (; $i < 100000; $i++) {
    $b[] = array('c' => $i);
}

echo "after generating: ", $m1 = xdebug_memory_usage(), "\n";

switch ($argv[1]) {
    case "s":
        echo "setting...\n";
        $a->set($b);
        break;
    case "b":
        echo "binding...\n";
        $a->bind($b);
        break;
}

echo "after action: ", xdebug_memory_usage(), "\n";

foreach ($a->a as $i) {
    foreach ($i as $inner) {
        continue;
    }
}

echo "after iterating: ", $m2 = xdebug_memory_usage(), "\n";
echo "difference: ", $m2 - $m1, "\n";