php - Fatal error on session_start() -

i have function track user session time.

function sessiontracker(){     ini_set('session.cookie_lifetime', 86400);     ini_set('session.gc_maxlifetime', 86400);     $sid = session_id();     if ($sid != '') {         //echo "session exists!";     } else {         //echo "no current session exists! starting...";         session_start();     }      if(!isset($_session['username']))     {         header("location:login.php");         exit();     } 

but i'm getting "maximum execution time of 30 seconds exceeded" when hits session_start(); line. there better function or how fix this? don't time, line.

function sessionreup() {     $time = $_server['request_time'];      //for 30 minute timeout, specified in seconds     $timeout_duration = 1800;      /*       here user’s last_activity timestamp. if       it’s set , indicates our $timeout_duration has passed,       blow away previous $_session data , start new one.     */     if (isset($_session['last_activity']) && ($time -     $_session['last_activity']) > $timeout_duration) {         session_unset();         session_destroy();         session_start();         header("location:login.php");         exit();     }      /*      finally, update last_activity our timeout      based on , not user’s login time.     */     $_session['last_activity'] = $time; } 

the code not show line, responsible long runtime. sessions stored hard disk. device really slow? did exchanged session handler?

but can reduce code to:

session_start();  if(!isset($_session['username'])) {     header("location:login.php");     exit(); }