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    <p>The session information is a resource that can only be used exclusively, and you have not taken this into account.</p> <p>Specifically, under default settings <code>session_start</code> causes PHP to acquire an exclusive lock on a file that contains the session data. This file is not unlocked until the script exits or <code>session_write_close</code> is called.</p> <p>In your example, <code>process.php</code> acquires the lock and starts working. In the meantime, <code>progress.php</code> tries to <code>session_start()</code> and cannot (due to the lock). Enough time needs to pass for <code>process.php</code> to complete and exit (thus releasing the lock) before the request for progress information can be satisfied.</p> <p>A small change you can make that will have immediate effect is to call <code>session_write_close</code> and <code>session_start</code> from within your worker loop:</p> <pre><code>for ($i=0; $i &lt;= $totalItems; $i++) { session_start(); $_SESSION['currentItem'] = $i; $_SESSION['percentComplete'] = round(($i / $totalItems * 100)); session_write_close(); } </code></pre> <p>This will allow the two scripts to take turns locking the session storage file, so you will see things working as intended. However, performance will <strong>tank</strong> (this is a really impolite way to treat the session storage file).</p> <p>If you had need to do something like this in the real world, it would be necessary to utilize something other than the session data to enable this exchange of information between the PHP scripts (e.g. an in-memory cache like APC or memcached).</p>
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    1. COI have apc installed I didn't even think to use that... I wasn't too concerned about performance as this script is only run by a single user once a week but I will give apc cache a try.
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Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

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