PHP memory recursive.

gistfile1.php

<?php


$performGC = false;

if ($performGC) {
    echo "GC collection will be done - app should not crash.\n";
}
else {
    echo "GC collection won't be done - app should crash.\n";
}
$dataSizeInKB = 128;

//Change this line if you tweak the parameters above.
ini_set('memory_limit', "64M");

$memData = '';

for ($y=0 ; $y<$dataSizeInKB ; $y++) {
    for ($x=0 ; $x<32 ; $x++) { //1kB
        $memData .= md5(time() + (($y * 32) + $x));
    }
}

file_put_contents("memdata.txt", $memData);

// This function creates a cyclic variable loop
function useSomeMemory($x) {
    $data = [];
    $data[$x] = file_get_contents("memdata.txt");
    $data[$x + 1] = &$data;
};


for($x=0 ; $x<1000 ; $x++) {
    useSomeMemory($x);
    if ($performGC == true) {
        gc_collect_cycles();
    }
}

printf("\nused: %10d | allocated: %10d | peak: %10d\n",
   memory_get_usage(),
   memory_get_usage(true),
   memory_get_peak_usage(true)
);