php memory leak test.

memory_leak.php

<?php

class test
{
    private $test = null;

    public function testMethod()
    {
        $this->test = "abc";
        $count = 0;
        while ($count <= 10000) {
            $this->test = "abc" . $this->test;
            $count++;
        }
        //echo $this->test . PHP_EOL;
    }

    public function testMethod2()
    {
        $test = "abc";
        $count = 0;
        while ($count <= 100000) {
            $test = "abc" . $test;
            $count++;
        }
    }
}

echo "[setup_start] memory usage : " . number_format(memory_get_usage() / 1048576, 2) . " MB" . PHP_EOL;

$objArr = [];
for($i = 0; $i <= 100; $i++) {
    $objArr[$i] = new test();
    $objArr[$i]->testMethod2();
    $objArr[$i]->testMethod();
    echo "[exec_end] memory usage : " . number_format(memory_get_usage() / 1048576, 2) . " MB" . PHP_EOL;

    $reflection = new \ReflectionObject($objArr[$i]);
        foreach ($reflection->getProperties() as $property) {
        $property->setAccessible(true);
        $property->setValue($objArr[$i], null);
    }
    $objArr[$i] = null;

    echo "[down_end] memory usage : " . number_format(memory_get_usage() / 1048576, 2) . " MB" . PHP_EOL;
}

$objArr = null;
echo "[down_end] memory usage : " . number_format(memory_get_usage() / 1048576, 2) . " MB" . PHP_EOL;
echo "[down_end] peak memory usage : " . number_format(memory_get_peak_usage() / 1048576, 2) . " MB" . PHP_EOL;