none
SQL Service Broker External Activator Verbose Logging

    Question

  • I recently created a External Activator setup.  While testing we are viewing the log file and concerned about the "Trying to launch application...".  I tried searching for the phrase but unable to find any references.  Can anyone shed some light whether I should be concerned.
    In our setup we are calling one web service that in turn calls another web service.


    2/3/2012 8:38:39 AM VERBOSE  Received event notification for server.dbo.myQueue
    2/3/2012 8:38:39 AM VERBOSE  Application process c:\test\myProcess.exe  "server" "myDB" "dbo" "myQueue"  was created: id = 3256
    2/3/2012 8:38:43 AM VERBOSE  Received event notification for server.myDB.dbo.myQueue
    2/3/2012 8:38:45 AM VERBOSE  Trying to launch application myProcess for [server].[myDB].[dbo].[myQueue] due to a missed notification
    2/3/2012 8:38:48 AM VERBOSE  Trying to launch application myProcess for [server].[myDB].[dbo].[myQueue] due to a missed notification
    2/3/2012 8:38:51 AM VERBOSE  Trying to launch application myProcess for [server].[myDB].[dbo].[myQueue] due to a missed notification
    2/3/2012 8:38:53 AM VERBOSE  Received event notification for server.myDB.dbo.myQueue
    2/3/2012 8:38:54 AM VERBOSE  Trying to launch application myProcess for [server].[myDB].[dbo].[myQueue] due to a missed notification
    2/3/2012 8:38:56 AM VERBOSE  Received event notification for server.myDB.dbo.myQueue
    2/3/2012 8:38:57 AM VERBOSE  Trying to launch application myProcess for [server].[myDB].[dbo].[myQueue] due to a missed notification
    2/3/2012 8:39:00 AM VERBOSE  Trying to launch application myProcess for [server].[myDB].[dbo].[myQueue] due to a missed notification
    2/3/2012 8:39:00 AM VERBOSE  Received event notification for server.myDB.dbo.myQueue
    2/3/2012 8:39:03 AM VERBOSE  Trying to launch application myProcess for [server].[myDB].[dbo].[myQueue] due to a missed notification
    2/3/2012 8:39:05 AM VERBOSE  Application process id = 3256 has exited.
    2/3/2012 8:39:05 AM VERBOSE  Trying to launch application myProcess for [server].[myDB].[dbo].[myQueue] due to a missed notification
    2/3/2012 8:39:05 AM VERBOSE  Application process c:\test\myProcess.exe  "server" "myDB" "dbo" "myQueue"  was created: id = 2672
    2/3/2012 8:39:05 AM VERBOSE  Application process id = 2672 has exited.

    Thanks,

    George Dellinger

    Friday, February 03, 2012 3:53 PM

All replies

  • Hi George,

    I would like to involve someone familiar with this issue to have a look, and give an update later. Thanks for your understanding.


    Stephanie Lv

    TechNet Community Support

    Monday, February 06, 2012 5:53 AM
  • Hi George,

    The service broker external activator application has an ApplicationMonitor class that is responsible for keeping track of specific applications as well as activating new instances of applications on receiving a notification. Remember that you have created an event notification on QUEUE_ACTIVATION that sends a message to your notification queue. SSBEA continually monitors the queue for messages. You will see a RPC:Completed profiler event like..

    exec sp_executesql N'WAITFOR (RECEIVE conversation_handle,message_type_name,service_contract_name,convert(xml, message_body) FROM [dbo].[NotificationQueue]), TIMEOUT @timeout',N'@timeout int',@timeout=3000

    When the message is received from this queue and analyzed, SSBEA will then startup an instance of your applications that will then receive messages from your target queue.

    What the VERBOSE message "Trying to launch application ..." means is that a event notification was triggered for a QUEUE_ACTIVATION (Broker:Activaion event in profiler) but was deemed missed by SSBEA, so it trys to start an instance of the applicaiton. When you have multiple QUEUE_ACTIVATION messages in your notification queue when SSBEA receives them from the queue you will get the message.

    You can investigate this closer by running a profiler trace with RPC:Completed and Broker:Activation events for the External Activator. This will show you the number of QUEUE_ACTIVATION events and the times the SSBEA receives messages from your notification queue.

    The message is nothing to worry about becaue SSBEA will continually check your notification queue for events. The time out value is 3 seconds and when it exits it will just execute again. One configuration change that I would make is to test increasing your max Concurrency value. (<Concurrency min="1" max="2" />) to see if they number of messages decreases.

    Hope this helps,

    Bill -- Microsoft CSS

    Tuesday, February 07, 2012 4:45 PM
  • "increasing your max Concurrency value" ... that fixed the msg processing app not launching.  Do we know the possible reasons msg app does not launch when  min/max = 1?  

    Mike McIver

    Wednesday, December 12, 2012 12:20 PM