title: Oracle AQ performance tuning
body: <p>I am using oracle database [11.2] with advanced queuing (AQ) w/ java JMS API. 
  My current oracle setup is default settings, with no additional tuning parameters.
  High level architecture:</p>
  
  <p><strong><em>Database enqueue message into persistent queue (sorted by priority)</em></strong></p>
  
  <pre><code>EXEC DBMS_AQADM.CREATE_QUEUE_TABLE (queue_table =&gt; 'order_queue_table', queue_payload_type =&gt; 'aqadm.order_message_t', sort_list=&gt;'PRIORITY,ENQ_TIME'); 
  EXEC DBMS_AQADM.CREATE_QUEUE (queue_name =&gt; 'order_queue', queue_table =&gt; 'order_queue_table'); 
  EXEC DBMS_AQADM.START_QUEUE (queue_name =&gt; 'order_queue');
  </code></pre>
  
  <p><em><strong>Java JMS consumer is dequeue messages with 3 concurrent threads.</em></strong> </p>
  
  <p>Everything is works great! and happy scenario, as long as messages in the queue @10K. 
  As soon as messages in queue <strong>doubles</strong> or triples <strong><em>dequeue</em></strong> performance goes significantly down!!!. </p>
  
  <p>I followed following link
  <a href="http://docs.oracle.com/cd/B28359_01/server.111/b28420/perform.htm" rel="nofollow">http://docs.oracle.com/cd/B28359_01/server.111/b28420/perform.htm</a></p>
  
  <p>Any suggestions on performance tuning on IO and AQ? </p>