for ($i = 0; $i < 3; $i++) {
    // start a span, register some events
    $span = $tracer->spanBuilder('loop-' . $i)->startSpan();

    $span->setAttribute('remote_ip', '1.2.3.4')
        ->setAttribute('country', 'USA');

    $span->addEvent('found_login' . $i, new Attributes([
        'id' => $i,
        'username' => 'otuser' . $i,
    ]));
    $span->addEvent('generated_session', new Attributes([
        'id' => md5((string) microtime(true)),
    ]));

    $span->end();
}