I was just poking around the UT code a bit and noticed that the user tracking function file is checking to see if there's a customer id (in other words its checking to see if the person is logged in or not) and then querying the database for the customers first name and last name every single time a new page loads up for that person.
So if the person is logged in we don't have to query the DB, their first and last name are already in the $_SESSION.
As long as your user tracking code snippet isn't one of the first things to be loaded, to help improve your load time you may try the following.
in includes/functions/extra_functions/user_tracking.php
find the following code
if ($_SESSION['customer_id'])
{
$customer = $db->Execute("select customers_firstname, customers_lastname from " . TABLE_CUSTOMERS . " where customers_id = '" . $_SESSION['customer_id'] . "'");
$wo_full_name = addslashes($customer->fields['customers_firstname'] . ' ' . $customer->fields['customers_lastname']);
}
```replace it with
if ($_SESSION['customer_id'])
{
$wo_full_name = $_SESSION['customer_first_name'] . ' ' . $_SESSION['customer_last_name'];
}