When load balancers have set timeouts at 30 seconds, this script will process requests that may take longer than 30 seconds (up to 15 minutes) without causing a timeout.

unzip.php

<?php
	$cmd = "zip -9prv content_backup.zip .";
	$pipe = popen($cmd, 'r');

	if (empty($pipe)) {
		throw new Exception("Unable to open pipe for command '$cmd'");
	}

	stream_set_blocking($pipe, false);
	echo "\n";

	while (!feof($pipe)) {
		fread($pipe, 1024);
		sleep(1);
		echo ".";
		flush();
	}

	echo "\n";
	echo "Complete";
	pclose($pipe);
?>