Who's Online Performance Issue

[kanine]

I believe our site was updated a week or so ago by the provider and I've since noticed a major slowdown on the "Who's Online" page. It now takes almost a minute for that to refresh. These are the details from the Server Info.

Server OS: Linux 2.6.9-023stab033.6-enterprise
Database: MySQL 5.0.67-community
Server Date: 03/07/2009 22:11:30
Database Date: 03/07/2009 22:11:30
Server Up Time: 22:11:30 up 60 days, 21:03, 0 users, load average: 0.92, 0.95, 1.10 HTTP
Server: Apache/2.2.11 (Unix) mod_ssl/2.2.11 OpenSSL/0.9.7a mod_auth_passthrough/2.1 mod_bwlimited/1.4 FrontPage/5.0.2.2635 mod_jk/1.2.25
PHP Version: 5.2.6 (Zend: 2.2.0)
PHP Memory Limit: 32M PHP Safe Mode: Off
PHP File Uploads: On
Max Size: 32M POST Max Size: 8M
Database Data Size: 1,978 kB
Database Index Size: 722 kB

Any ideas?

[frank18]

I would monitor the site for another week or so - just to make sure the download status of the site remains unchanged, and then ask some serious questions to my hosting company.

If there is no plausible explanation then you may want to consider changing to another host.

Frank

www.zencart.frnt.org

[DrByte]

The delay is likely due to ip-to-hostname lookup delays caused by poorly-configured server nameserver settings ... which only your hosting company can fix.

[kanine]

We are still suffering from this issue. The reverse lookups appear OK because I've noticed more recently that if I hit the "Stop" button in IE immediately after entering the who's online page all the details are there. So the issue seems to be something to do with displaying the cart information.

Is there a way to stop zc from displaying the cart info so I can isolate this issue?

[kanine]

I've isolated the problem area to the following code, can anyone give me pointers as to why the response from this section appears to be causing a timeout?

<?php
  $heading = array();
  $contents = array();
  if ($info) {
    $heading[] = array('text' => '<b>' . TABLE_HEADING_SHOPPING_CART . '</b>');

    if (STORE_SESSIONS == 'db') {
      $session_data = $db->Execute("select value from " . TABLE_SESSIONS . "
                                    WHERE sesskey = '" . $info . "'");

      $session_data = trim($session_data->fields['value']);
    } else {
      if ( (file_exists(zen_session_save_path() . '/sess_' . $info)) && (filesize(zen_session_save_path() . '/sess_' . $info) > 0) ) {
        $session_data = file(zen_session_save_path() . '/sess_' . $info);
        $session_data = trim(implode('', $session_data));
      }
    }

    if ($length = strlen($session_data)) {
      if (PHP_VERSION < 4) {
        $start_id = strpos($session_data, 'customer_id[==]s');
        $start_cart = strpos($session_data, 'cart[==]o');
        $start_currency = strpos($session_data, 'currency[==]s');
        $start_country = strpos($session_data, 'customer_country_id[==]s');
        $start_zone = strpos($session_data, 'customer_zone_id[==]s');
      } else {
        $start_id = strpos($session_data, 'customer_id|s');
        $start_cart = strpos($session_data, 'cart|O');
        $start_currency = strpos($session_data, 'currency|s');
        $start_country = strpos($session_data, 'customer_country_id|s');
        $start_zone = strpos($session_data, 'customer_zone_id|s');
      }

      for ($i=$start_cart; $i<$length; $i++) {
        if ($session_data[$i] == '{') {
          if (isset($tag)) {
            $tag++;
          } else {
            $tag = 1;
          }
        } elseif ($session_data[$i] == '}') {
          $tag--;
        } elseif ( (isset($tag)) && ($tag < 1) ) {
          break;
        }
      }

      $session_data_id = substr($session_data, $start_id, (strpos($session_data, ';', $start_id) - $start_id + 1));
// fix nnobo bug
      $session_data_cart = substr($session_data, $start_cart, $i - $start_cart);
      $session_data_currency = substr($session_data, $start_currency, (strpos($session_data, ';', $start_currency) - $start_currency + 1));
      $session_data_country = substr($session_data, $start_country, (strpos($session_data, ';', $start_country) - $start_country + 1));
      $session_data_zone = substr($session_data, $start_zone, (strpos($session_data, ';', $start_zone) - $start_zone + 1));

      session_decode($session_data_id);
      session_decode($session_data_currency);
      session_decode($session_data_country);
      session_decode($session_data_zone);
      session_decode($session_data_cart);

      if (PHP_VERSION < 4) {
        $broken_cart = $cart;
        $cart = new shoppingCart;
        $cart->unserialize($broken_cart);
      }

      if (is_object($_SESSION['cart'])) {
        $contents[] = array('text' => $full_name . ' - ' . $ip_address . '<br />' . $info);
        $products = $_SESSION['cart']->get_products();
        for ($i = 0, $n = sizeof($products); $i < $n; $i++) {
          $contents[] = array('text' => $products[$i]['quantity'] . ' x ' . '<a href="' . zen_href_link(FILENAME_CATEGORIES, 'cPath=' . zen_get_product_path($products[$i]['id']) . '&pID=' . $products[$i]['id']) . '">' . $products[$i]['name'] . '</a>');
// cPath=23&pID=74
        }

        if (sizeof($products) > 0) {
          $contents[] = array('text' => zen_draw_separator('pixel_black.gif', '100%', '1'));
          $contents[] = array('align' => 'right', 'text'  => TEXT_SHOPPING_CART_SUBTOTAL . ' ' . $currencies->format($_SESSION['cart']->show_total(), true, $_SESSION['currency']));
        } else {
          $contents[] = array('text' => TEXT_EMPTY_CART);
        }
      }
    }
  }

  if ( (zen_not_null($heading)) && (zen_not_null($contents)) ) {
    echo '            <td width="25%" valign="top">' . "\n";

    $box = new box;
    echo $box->infoBox($heading, $contents);

    echo '            </td>' . "\n";
  }
?>

If I remove this section of code the who's online responds instantly with a list of users and their cart status. But I would like to be able to see what is in their carts as it provides useful info.

[mprough]

This should likely be increased, we find 90 to be a better match

PHP Memory Limit: 32M PHP Safe Mode: Off

Also, we have tweaked the SQL quite a bit on our servers. This tool is a great help...
You can download it and run it by typing perl mysqltuner.pl

http://mysqltuner.com/mysqltuner.pl

Some of the settings we tweaked for the Zen Cart servers are below..

tmp_table_size=128M
max_heap_table_size=128M
key_buffer_size=64M
innodb_buffer_pool_size=128M

~Melanie

[peachgifts]

I modified my who's online to refresh every 30 secs it works fine:

<script type="text/javascript">
<!--
function init()
{
timedRefresh(30000);
cssjsmenu('navbar');
if (document.getElementById)
{
var kill = document.getElementById('hoverJS');
kill.disabled = true;
}
}
// -->
</script>
<script type="text/JavaScript">
<!--
function timedRefresh(timeoutPeriod) {
setTimeout("location.reload(true);",timeoutPeriod);
}
// -->
</script>
</head>


<body onLoad="init()">

peachgifts,
diylearnwithme.com

Zen Cart 1.3.8a
File: whos_online.php