<?php
$start = microtime(true);
function bytesToSize($bytes, $precision = 2) {
$symbols = array('B', 'Kb', 'Mb', 'Gb', 'Tb', 'Pb', 'Eb', 'Zb', 'Yb');
$exp = (int)floor(log($bytes) / log(1024));
return sprintf('%.'. $precision .'f '. $symbols[$exp], $bytes / pow(1024, floor($exp)));
}
function mem() {
return bytesToSize(memory_get_usage(true));
}
function test($msg, $test) {
$t = microtime(true);
$test($msg);
echo $msg .': <b>'. sprintf('%.6f', microtime(true) - $t) .'</b>'. PHP_EOL;
}
$array = range(0, 30000);
test('foreach', function ($msg) use ($array) {
echo $msg . ' before loop mem: '. mem() .PHP_EOL;
foreach ($array as $v) {
$b = $v;
}
echo $msg . ' after loop mem: '. mem() .PHP_EOL;
});
test('foreach ref', function ($msg) use ($array) {
echo $msg . ' before loop mem: '. mem() .PHP_EOL;
foreach ($array as &$v) {
$b = $v;
}
unset($v);
echo $msg . ' after loop mem: '. mem() .PHP_EOL;
});
test('for', function ($msg) use ($array) {
echo $msg . ' before loop mem: '. mem() .PHP_EOL;
$so = count($array);
for ($i = 0; $i < $so; ++$i) {
$b = $array[$i];
}
echo $msg . ' after loop mem: '. mem() .PHP_EOL;
});
test('while each -> list', function ($msg) use ($array) {
echo $msg . ' before loop mem: '. mem() .PHP_EOL;
while (list($k, $v) = each($array)) {
$b =$v;
}
echo $msg . ' after loop mem: '. mem() .PHP_EOL;
});
echo 'Memory peak: ' . round(memory_get_peak_usage() / 1048576, 3) .PHP_EOL;
echo sprintf('%.6f', microtime(true) - $start) .'</b>'. PHP_EOL;
preferences:
30.87 ms | 402 KiB | 5 Q