javascript - How to use Comet and Push technique using AJAX and PHP -

i calling ajax after each 5 seconds update info of current logged-in user database table in php.

but creates heavy load on website, , website down after time when there multiple users logged-in on website.

is there way use other techniques comet or push improve script?

here code using:

javascript code:

jquery(document).ready(function ($) {        update_data();      function update_data() {      $.ajax({        type: "post",        url: "$url",        data: {update_current_time:1},        success: function(response){          settimeout(update_data, 5000);        },        error: function(){          settimeout(update_data, 5000);        }      });    } }); 

php code:

if(isset($_post['update_current_time'])) {    $query = "update users set user_timer=now()  user_id=".$_session['id'];    $db->execute();    echo 'success';    die; } 

to use push or comet need setup "webserver" listen port. cannot solved using pure php needs listener setup (unless create on listening server using php).

to stay @ php can check out ratchet.

another common way go node.js server parrallel webserver.