单例模式在PHP中的性能测试与优化

class Singleton
{
    private static $instance;

    private function __construct()
    {
        // 私有构造函数，防止类外实例化
    }

    public static function getInstance()
    {
        if (!self::$instance) {
            self::$instance = new self();
        }

        return self::$instance;
    }

    // 其他方法
}

class Test
{
    public function run()
    {
        $startTime = microtime(true);

        for ($i = 0; $i < 100000; $i++) {
            $singleton = Singleton::getInstance();
        }

        $endTime = microtime(true);
        $executionTime = round($endTime - $startTime, 4);

        echo "执行100000次单例模式实例化耗时：{$executionTime} 秒
";

        $startTime = microtime(true);

        for ($i = 0; $i < 100000; $i++) {
            $instance = new Singleton();
        }

        $endTime = microtime(true);
        $executionTime = round($endTime - $startTime, 4);

        echo "执行100000次类实例化耗时：{$executionTime} 秒
";
    }
}

$test = new Test();
$test->run();

class Singleton
{
    private static $instance;
    private static $lock;

    private function __construct()
    {
        // 私有构造函数，防止类外实例化
    }

    public static function getInstance()
    {
        if (!self::$instance) {
            self::$lock = true;
            if (!self::$instance) {
                self::$instance = new self();
            }
            self::$lock = false;
        }

        return self::$instance;
    }
}