Codeigniter 3会话错误500

I'm having problems with sessions in the CI 3 .

I'm having the "error 500" every time that users login on my website.

In the past I had same problems because I created on login sessions and the cookie size was only 4k. Becouse of this, today I use database to store my sessions and it seems that I still have the cookie size limite problem.

I disable the creation of some sessions ( randomly sessions to make sure the problem is not of specifies session ) and the problem (error 500) stop. When I uncomment all sessions, I get the error 500.

Why this is happening if I use database sessions and the filed are TEXT?

Part of the code:

$this->session->set_userdata('l_usr', $user_id);
$this->session->set_userdata('l_usr_email', $user_email);
$this->session->set_userdata('l_usr_login', $user_login);
$this->session->set_userdata('l_nivel', $user_nivelacesso);
$this->session->set_userdata('l_usr_genero', $user_genero);
//$this->session->set_userdata('token', $token_id);
$this->session->set_userdata('l_usr_pic_perfil', "usuarios/".$user_id."/perfil/".$user_foto_perfil);
//$this->session->set_userdata('l_usr_pic_avatar', "usuarios/".$user_id."/perfil/".$user_foto_avatar);

Tanks