CI调用存储过程很慢怎么提速，mysql存储过程本身执行很快，但是在php调用就要0.8s

<code>                            $this -> db -> reconnect();                            $mysqli = new mysqli();                            $mysqli -> query("SET NAMES utf8");                            if (mysqli_connect_errno()) {                                    printf('Connect failed: %s\n', mysqli_connect_error());                                    exit();                            }                            if($set){                                    $mysqli ->multi_query("SET {$set} ");                            }                            //$query  = 'CALL p_MyFrontAndBackListTie(2)';                            /* execute multi query */                            if ($mysqli -> multi_query($query)) {                                    do {                                            /* store first result set */                                            if ($result = $mysqli -> store_result()) {                                                     while ($row = $result -> fetch_all()) {                                                            $all_result[] = $row;                                                      }                                                    $result -> free();                                            }                                    }                                    while ($mysqli -> next_result());                            }                                    /* close connection */                            $mysqli -> close();                            return $all_result;</code>