I have the following code

```
function openDBConn($params){
    $conn_mode = $params['conn_mode'];
    $db_conn = $params['db_conn'];

    //create connections
    if(empty($db_conn->info)) {
        $db_conn = new mysqli("localhost", $user, $password, "database");
        $db_conn->set_charset('UTF8'); 
        $mysqli_error = $db_conn->connect_error;
    }

    if($mysqli_error !== NULL){ 
        die('Could not connect <br/>'. $mysqli_error); 
    }else{ 
        return $db_conn; 
    }
}

//close db connection
function closeDBConn( $params ){
    $db_conn = $params['db_conn'];
    $db_conn->close;
}

//used as below
$db_conn = openDBConn();

save_new_post( $post_txt, $db_conn );

closeDBConn( array('db_conn'=>$db_conn));

```

From time to time, I get the "Could not connect. Too many connections" error. 
This tends to happen when I have Google bot scanning my website.

This problem seems to have started ever since upgrading to MySQLi from MySQL.
Is there any advice on how ensure all connections are closed?

Thanks