If I just had two threads to signal I would create a queue for each one and just enqueue the messages when I felt the need. the thread can then block on a queue read and do nothing until it gets a message

Updated to mention threads->create

...
use Thread::Queue;

my $conn_q = thread::queue->new()
my $rev_q  = thread::queue->new()

sub connection_check {
   while (my $msg = $conn_q->dequeue) { # will block 'til it gets sign
+aled
      # Do something
   }
}
...
# in main
$conn_thread = threads->create('connection_check');
$conn_q->enqueue("Get on with it");
[download]

$min % 55 will be zero at 55 and at 0 minutes. Perhaps two timers would do your trick

my %timer = (
    check_conn => 0,
    check_rev  => 0,
};
my %interval = (
    check_conn => 5,  # check conn every 5 min
    check_rev  => 55, # and revocation at 55min
};

while (1) {
    my $now = time;
    if ($now + interval{check_conn} * 60 > $timmer{check_conn} ) { #pa
+ssed mark
        $timer{check_conn} = $now + interval{check_conn} * 60;
        # signal conn thread to do its work
        $conn_q->enqueue("Get on with it"); 
    }
    # similar for check rev list
    #
    sleep 10; # or 60, or 300...
}
[download]

Cheers,
R.