| Re: [paho-dev] Long timeouts to real sites with no MQTT |
Hi Steven,
The connection timeout is there for when a socket is successfully
connected but the other end doesn't respond to the initial MQTT
connect packet exchange in a timely fashion.
I've run your code a few times and it times out for my after roughly
5-6 seconds:
nol@noltop:/tmp/Mqttv3ClientOut/ship$ java -classpath
org.eclipse.paho.client.mqttv3.jar:. SuperSimple
(00:05.624)Exception: Unable to connect to server
I get exactly the same results when I change the code to remove the
MqttClient altogether and just try to connect a raw socket (code
attached). Could you give that a go and see what you get?
I also get the same result when I simply try telnet'ing to that server/port:
nol@noltop:~$ time telnet some.company.net 1883
Trying 82.98.86.161...
telnet: Unable to connect to remote host: Connection refused
real 0m6.121s
user 0m0.000s
sys 0m0.000s
What operating system are you running this on? I suspect there is an
underlying socket level timeout coming into play here.
Cheers,
Nick
On 26 February 2013 03:29, Steven Luke <stevejluke@xxxxxxxxx> wrote:
> When I make a connection to a valid looking Host Address, but which does not
> have an MQTT server running I get a seriously long timeout (I think it may
> actually never end in some cases). I tried setting the Connection Timeout
> to 20, or 5, or anything, but it doesn't work. Anything I can try to make
> the client realize the connection is no-good earlier? Alternatively is
> there something I can manually do in another thread to make the connection
> stop trying?
>
> This is a big issue for me, because the setting will be user-configurable
> and if it takes this long to fail it means a negative and very visible user
> experience. I would like it to fail in 30 seconds or less so I can prompt
> for them to modify the address without making them wait for minutes to set
> up.
>
> Thanks,
> Steve
>
> Here is sample code which shows the problem. In plain desktop Java it takes
> a consistent 1 minute, 3 seconds to fail. I use the same code on android,
> and on WiFi it takes about the same time (a little over a minute), but on
> 3G/4G it takes 2+ minutes, and I timed one (google.com) at >10 minutes
> before killing it.
>
> public class SuperSimple
> {
> public static final String timeDiffFormat = "%1$tM:%1$tS.%1$tL";
> private static MqttClient client;
>
> public static void main(String... args)
> {
> final long startTime = System.currentTimeMillis();
> try
> {
> client = new MqttClient("tcp://some.company.net:1883",
> "this_should_fail_fast");
>
> MqttConnectOptions mOptions = new MqttConnectOptions();
> mOptions.setKeepAliveInterval(20);
> mOptions.setConnectionTimeout(20);
> client.connect(mOptions);
>
> }
> catch (MqttException mEx)
> {
> long errorTime = System.currentTimeMillis();
> Date difference = new Date(errorTime - startTime);
> String time = String.format(Locale.US, timeDiffFormat,
> difference);
> String message = mEx.getMessage();
> System.out.printf("(%s)Exception: %s%n", time, message);
> }
>
> try
> {
> client.disconnect();
> }
> catch (MqttException e)
> {
> //This always happens: already disconnected.
> }
> }
> }
>
>
> _______________________________________________
> paho-dev mailing list
> paho-dev@xxxxxxxxxxx
> http://dev.eclipse.org/mailman/listinfo/paho-dev
>
Attachment:
SocketTest.java
Description: Binary data