mention DoS attacks too

mojolicious · Jan 31, 2016 · 37478b7 · 37478b7
1 parent a8a640e
commit 37478b7
Showing 1 changed file with 15 additions and 14 deletions.
diff --git a/lib/Mojolicious/Guides/FAQ.pod b/lib/Mojolicious/Guides/FAQ.pod
@@ -251,31 +251,32 @@ server closed the connection before the user agent could receive the whole
 response or that the user agent got destroyed, which forces all connections to
 be closed immediately.
 
-=head2 What does "Worker 31842 has no heartbeat, restarting" mean?
-
-As long as they are accepting new connections, worker processes of all built-in
-preforking web servers send heartbeat messages to the manager process at
-regular intervals, to signal that they are still responsive. A blocking
-operation such as an infinite loop in your application can prevent this, and
-will force the affected worker to be restarted after a timeout. This timeout
-defaults to C<20> seconds and can be extended with the attribute
-L<Mojo::Server::Prefork/"heartbeat_timeout"> if your application requires it.
-
 =head2 What does "Write congestion" mean?
 
 All built-in web servers are based on an event-loop, and can therefore only
 write data when the event-loop is in control. So if you are writing a lot of
 data at once to your WebSocket, it all has to be buffered, which can be very
-inefficient. So you will be notified once the data waiting to be written reaches
-a certain size, which defaults to 16MB, and can be changed for each connection
-individually with L<Mojo::IOLoop::Stream/"high_water_mark">. To avoid this, all
-you have to do, is to wait for all data to be written, before sending more.
+inefficient, and even be used for denial-of-service attacks. So you will be
+notified once the data waiting to be written reaches a certain size, which
+defaults to 16MB, and can be changed for each connection individually with
+L<Mojo::IOLoop::Stream/"high_water_mark">. To avoid this, you can simply wait
+for all data to be written, before sending more.
 
   $c->send('First message!' => sub {
     my $c = shift;
     $c->send('Second message!');
   });
 
+=head2 What does "Worker 31842 has no heartbeat, restarting" mean?
+
+As long as they are accepting new connections, worker processes of all built-in
+preforking web servers send heartbeat messages to the manager process at
+regular intervals, to signal that they are still responsive. A blocking
+operation such as an infinite loop in your application can prevent this, and
+will force the affected worker to be restarted after a timeout. This timeout
+defaults to C<20> seconds and can be extended with the attribute
+L<Mojo::Server::Prefork/"heartbeat_timeout"> if your application requires it.
+
 =head1 MORE
 
 You can continue with L<Mojolicious::Guides> now or take a look at the