Timer定时器同步问题

echo date('Y-m-d H:i:s') . '开始' . PHP_EOL;
$timeId = Timer::add(3, function () use (&$timeId) {
    echo 'Timer:' . date('Y-m-d H:i:s');
    return;
}, [], false);
echo date('Y-m-d H:i:s') . '结束' . PHP_EOL;

composer require workerman/workerman ^5.0.0-beta.7
composer require revolt/event-loop ^1.0.1

echo date('Y-m-d H:i:s') . '开始' . PHP_EOL;
Timer::sleep(3);
echo 'Timer:' . date('Y-m-d H:i:s');
echo date('Y-m-d H:i:s') . '结束' . PHP_EOL;