PHP对多个数组进行排序

I have a PHP report which goes out to an array of servers to get their uptime. Then present the uptime in a table. Very simple.

I'm looking to see how to sort this array so that the highest uptime is at the top of the list.

I know about arsort() but I don't know how to apply it to this statement because of the foreach building the table dynamically.

Here's my code:

$servers = server1,server2,server3

foreach ($servers as $srv) {
    $output = array(); // Reset the $output array each time
    exec("/root/get_report_uptime.sh $srv",$output,$retval);
    echo "<tr>";
        echo "<td><a href='http://$srv/' target='_blank'>$srv</a></td>";
        echo "<td>$output[0] days</td>";
    echo "</tr>";
}

$output[0] returns a number like "100". Looking to sort by $output[0] while keeping the $srv linked to it.

$days = array()
foreach ($servers as $srv) {
    $output = array(); // Reset the $output array each time
    exec("/root/get_report_uptime.sh $srv",$output,$retval);
    $days[$srv] = $output[0];
}
arsort($days);
foreach($days as $srv => $day) {
    echo "<tr>";
        echo "<td><a href='http://".$srv."/' target='_blank'>".$srv."</a></td>";
        echo "<td>".$day." days</td>";
    echo "</tr>";
}