Why do the JMS dbms_aqadm.add_subscriber and dbms_aqadm.remove_subscriber calls sometimes hang when there are concurrent enqueues or dequeues happening on the same queue to which these calls are issued?
Answer Posted / munnu
Add_subscriber and remove_subscriber are administrative operations on a queue. Though AQ does not prevent applications from issuing administrative and operational calls concurrently, they are executed serially. Both add_subscriber and remove_subscriber will block until pending transactions that have enqueued or dequeued messages commit and release the resources they hold. It is expected that adding and removing subscribers will not be a frequent event. It will mostly be part of the setup for the application. The behavior you observe will be acceptable in most cases. The solution is to try to isolate the calls to add_subscriber and remove_subscriber at the setup or cleanup phase when there are no other operations happening on the queue. That will make sure that they will not stay blocked waiting for operational calls to release resources.
| Is This Answer Correct ? | 0 Yes | 0 No |
Post New Answer View All Answers
What is the difference between a queue and a topic?
What is jms and how it works?
What is difference between jms and activemq?
How do I configure jms security?
Is jms a message broker?
Explain about message selector?
Explain the difference between topic and queue?
What is jms protocol?
What is jms queue in java?
Which types of jdbc databases does weblogic jms support?
What are the different parts of a jms message?
What type of messaging is provided by JMS?
What are jms topics and queues?
How may messaging models do JMS provide for and what are they?
How to consume message from jms queue in soa 12c?