Problema di disconnessione Tomcat / BlazeDS / ActiveMQ

Question

Stiamo riscontrando disconnessioni sul nostro stack Tomcat / BlazeDS / ActiveMQ. Sebbene il nostro BlazeDS StreamingAMFChannel sia configurato con i minuti di inattività-time predefiniti pari a 0, sembra scadere dopo circa 30 minuti di inattività (consultare il registro). Il client non fa alcuna richiesta durante quel periodo e non stiamo nemmeno inviando messaggi dall'argomento ActiveMQ.

Abbiamo abilitato la registrazione di debug su activeMQ e BlazeDS e vediamo che BlazeDS sta rimuovendo il consumatore. Sfortunatamente non c'è nessun messaggio di registro prima del messaggio di disconnessione, quindi non possiamo davvero tracciare quando questo viene chiamato all'interno di BlazeDS.

Qualcun altro ha sperimentato questo o qualcuno può fornire una soluzione?

* Registro ActiveMQ *

11 Mar 2009 16:25:47,405 [ActiveMQ Transport: tcp:///127.0.0.1:49971] DEBUG activemq.broker.region.AbstractRegion  - Removing consumer: ID:TMSNEC02.traficon.int-52586-1236783284912-2:3:1:1
11 Mar 2009 16:25:47,406 [ActiveMQ Transport: tcp:///127.0.0.1:49971] DEBUG activemq.broker.region.AbstractRegion  - Removing consumer: ID:TMSNEC02.traficon.int-52586-1236783284912-2:3:-1:1
11 Mar 2009 16:25:47,407 [ContainerBackgroundProcessor[StandardEngine[Catalina]]] DEBUG activemq.transport.tcp.TcpTransport  - Stopping transport tcp://localhost/127.0.0.1:61616
11 Mar 2009 16:25:47,408 [ActiveMQ Transport Stopper: /127.0.0.1:49971] DEBUG apache.activemq.broker.TransportConnection  - Stopping connection: /127.0.0.1:49971
11 Mar 2009 16:25:47,409 [ActiveMQ Transport Stopper: /127.0.0.1:49971] DEBUG activemq.transport.tcp.TcpTransport  - Stopping transport tcp:///127.0.0.1:49971
11 Mar 2009 16:25:47,413 [ActiveMQ Transport Stopper: /127.0.0.1:49971] DEBUG apache.activemq.broker.TransportConnection  - Stopped connection: /127.0.0.1:49971
11 Mar 2009 16:25:47,417 [ActiveMQ Transport Stopper: /127.0.0.1:49971] DEBUG apache.activemq.broker.TransportConnection  - Connection Stopped: /127.0.0.1:49971
11 Mar 2009 16:25:47,427 [ActiveMQ Transport: tcp:///127.0.0.1:50680] DEBUG activemq.broker.region.AbstractRegion  - Removing consumer: ID:TMSNEC02.traficon.int-52586-1236783284912-2:4:1:1
11 Mar 2009 16:25:47,430 [ActiveMQ Transport: tcp:///127.0.0.1:50680] DEBUG activemq.broker.region.AbstractRegion  - Removing consumer: ID:TMSNEC02.traficon.int-52586-1236783284912-2:4:-1:1
11 Mar 2009 16:25:47,431 [ContainerBackgroundProcessor[StandardEngine[Catalina]]] DEBUG activemq.transport.tcp.TcpTransport  - Stopping transport tcp://localhost/127.0.0.1:61616
11 Mar 2009 16:25:47,431 [ActiveMQ Transport Stopper: /127.0.0.1:50680] DEBUG apache.activemq.broker.TransportConnection  - Stopping connection: /127.0.0.1:50680
11 Mar 2009 16:25:47,431 [ActiveMQ Transport Stopper: /127.0.0.1:50680] DEBUG activemq.transport.tcp.TcpTransport  - Stopping transport tcp:///127.0.0.1:50680
11 Mar 2009 16:25:47,435 [ActiveMQ Transport Stopper: /127.0.0.1:50680] DEBUG apache.activemq.broker.TransportConnection  - Stopped connection: /127.0.0.1:50680
11 Mar 2009 16:25:47,438 [ActiveMQ Transport Stopper: /127.0.0.1:50680] DEBUG apache.activemq.broker.TransportConnection  - Connection Stopped: /127.0.0.1:50680
11 Mar 2009 16:25:47,439 [ActiveMQ Transport: tcp:///127.0.0.1:50681] DEBUG activemq.broker.region.AbstractRegion  - Removing consumer: ID:TMSNEC02.traficon.int-52586-1236783284912-2:5:1:1
11 Mar 2009 16:25:47,439 [ActiveMQ Transport: tcp:///127.0.0.1:50681] DEBUG activemq.broker.region.AbstractRegion  - Removing consumer: ID:TMSNEC02.traficon.int-52586-1236783284912-2:5:-1:1
11 Mar 2009 16:25:47,440 [ContainerBackgroundProcessor[StandardEngine[Catalina]]] DEBUG activemq.transport.tcp.TcpTransport  - Stopping transport tcp://localhost/127.0.0.1:61616
11 Mar 2009 16:25:47,440 [ActiveMQ Transport Stopper: /127.0.0.1:50681] DEBUG apache.activemq.broker.TransportConnection  - Stopping connection: /127.0.0.1:50681
11 Mar 2009 16:25:47,441 [ActiveMQ Transport Stopper: /127.0.0.1:50681] DEBUG activemq.transport.tcp.TcpTransport  - Stopping transport tcp:///127.0.0.1:50681
11 Mar 2009 16:25:47,441 [ActiveMQ Transport Stopper: /127.0.0.1:50681] DEBUG apache.activemq.broker.TransportConnection  - Stopped connection: /127.0.0.1:50681
11 Mar 2009 16:25:47,441 [ActiveMQ Transport Stopper: /127.0.0.1:50681] DEBUG apache.activemq.broker.TransportConnection  - Connection Stopped: /127.0.0.1:50681

* Registro BlazeDS *

[BlazeDS]03/11/2009 15:55:39.776 [DEBUG] [Endpoint.AMF] Serializing AMF/HTTP response
Version: 3
  (Message #0 targetURI=/4/onResult, responseURI=)
    (Externalizable Object #0 'DSK')
      (Externalizable Object #1 'flex.messaging.io.ArrayCollection')
        (Array #2)
1.236783339776E12
(Byte Array #3, Length 16)
(Byte Array #4, Length 16)
(Byte Array #5, Length 16)

[BlazeDS]03/11/2009 16:25:47.391 [INFO] [Service.Message.JMS] JMS consumer for JMS destination 'java:comp/env/eventMessagesFlexTopic' is being removed from the JMS adapter
[BlazeDS]03/11/2009 16:25:47.392 [INFO] [Service.Message.JMS] JMS consumer for JMS destination 'java:comp/env/eventMessagesFlexTopic' is stopping.
[BlazeDS]03/11/2009 16:25:47.417 [DEBUG] [Client.MessageClient] MessageClient with clientId '7A98D7BC-F0B3-922C-A968-BE0BFB7D9080' for destination 'eventMessageFeed' has been invalidated.
[BlazeDS]03/11/2009 16:25:47.419 [INFO] [Service.Message.JMS] JMS consumer for JMS destination 'java:comp/env/detectorsFlexTopic' is being removed from the JMS adapter
[BlazeDS]03/11/2009 16:25:47.423 [INFO] [Service.Message.JMS] JMS consumer for JMS destination 'java:comp/env/detectorsFlexTopic' is stopping.
[BlazeDS]03/11/2009 16:25:47.435 [DEBUG] [Client.MessageClient] MessageClient with clientId '7A9BC826-2199-C772-0A1B-FE6FAE9F7402' for destination 'detectorsFeed' has been invalidated.
[BlazeDS]03/11/2009 16:25:47.438 [INFO] [Service.Message.JMS] JMS consumer for JMS destination 'java:comp/env/scenariosFlexTopic' is being removed from the JMS adapter
[BlazeDS]03/11/2009 16:25:47.438 [INFO] [Service.Message.JMS] JMS consumer for JMS destination 'java:comp/env/scenariosFlexTopic' is stopping.
[BlazeDS]03/11/2009 16:25:47.440 [DEBUG] [Client.MessageClient] MessageClient with clientId '7A9BCE40-A0DA-18D6-9FA1-6D6AA2088256' for destination 'scenarioMessageFeed' has been invalidated.
[BlazeDS]03/11/2009 16:25:47.441 [DEBUG] [Client.FlexClient] FlexClient with id '7A95FDE9-0091-B1CD-3660-D8E9CD6CD3E6' has been invalidated.
[BlazeDS]03/11/2009 16:25:47.441 [DEBUG] [Endpoint.StreamingAMF] Endpoint with id 'my-streaming-amf' is streaming message: Flex Message (flex.messaging.messages.CommandMessage)
operation = disconnect
clientId = null
correlationId = null
destination = null
messageId = 7ED1C45A-10A7-BFBB-E24E-94B9C03047EE
timestamp = 1236785147441
timeToLive = 0
body = null
[BlazeDS]03/11/2009 16:25:47.441 [DEBUG] [Endpoint.FlexSession] FlexSession with id '71A76CA22AC435285736F6DB0E38AC11' for an Http-based client connection has been invalidated.
[BlazeDS]03/11/2009 16:25:47.444 [DEBUG] [Client.FlexClient] FlexClient with id '7A941468-80E5-8343-A2AE-A3AFFA135734' has been invalidated.
[BlazeDS]03/11/2009 16:25:47.444 [DEBUG] [Endpoint.FlexSession] FlexSession with id '1238AA40EF8B016F3942C6D6BDBA29B9' for an Http-based client connection has been invalidated.
[BlazeDS]03/11/2009 16:25:47.444 [DEBUG] [Endpoint.StreamingAMF] Streaming thread 'http-8080-1' for endpoint with id 'my-streaming-amf' is releasing connection and returning to the request handler pool.
[BlazeDS]03/11/2009 16:25:47.444 [INFO] [Endpoint.FlexSession] Number of streaming clients for FlexSession with id '71A76CA22AC435285736F6DB0E38AC11' is 0.
[BlazeDS]03/11/2009 16:25:47.444 [DEBUG] [Endpoint.StreamingAMF] Number of streaming clients for endpoint with id 'my-streaming-amf' is 0.
[BlazeDS]03/11/2009 16:25:47.489 [DEBUG] [Endpoint.FlexSession] FlexSession created with id 'E5BCC7617F3937139CCAD377EEB85D45' for an Http-based client connection.
[BlazeDS]03/11/2009 16:25:47.489 [INFO] [Endpoint.General] Channel endpoint my-streaming-amf received request.

Answer 1

Abbiamo risolto questo problema inviando un messaggio keep-alive dal client al server ogni 30 secondi. Apparentemente era la FlexSession che stava scadendo poiché segue il timeout di sessione predefinito di Tomcat. Poiché il messaggio keep-alive viene inviato a un intervallo basso, impostiamo anche il timeout della sessione su un valore basso sul server, il che comporta un miglioramento del consumo di memoria sul server.

Answer 2

Puoi rispondere a un evento di disconnessione e riconnetterti se necessario.