deltalounge

If you are using AQ within Oracle ESB there might be a point in time you want to tune AQ performance. In this post you’ll find the results of Metalink research, and our experience on a production system.

Queue compatibility

When creating the ORAESB schema (in version 10.1.3.3) using the script $ORACLE_HOME/integration/esb/sql/oracle/create_esb_topics.sql, the queues are created with 8.1 compatibility. This is solved in 10.1.3.4. To alter this find the statement

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dbms_aqadm.create_queue_table
    ( Queue_table => qtablename
    , Queue_payload_type => 'SYS.AQ$_JMS_TEXT_MESSAGE'
    , multiple_consumers => true
    , compatible => '8.1'
    );

and change this to:

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dbms_aqadm.create_queue_table
    ( Queue_table => qtablename
    , Queue_payload_type => 'SYS.AQ$_JMS_TEXT_MESSAGE'
    , multiple_consumers => true
    , compatible => '10.2'
    );

if you already created the queues, use this statement:

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dbms_aqadm.migrate_queue_table
    ( queue_table => 'ESB_JAVA_DEFERRED'
    , compatible => '10.2'
    );

If you’re not sure check the compatibility with this query:

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SELECT queue_table
,      compatible
,      recipients
FROM   dba_QUEUE_tables
WHERE  owner = 'ORAESB'
;

Streams pool size

Verify the current stream_pool_size using the following query:

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SELECT component
,      current_size/1024/1024 "CURRENT_SIZE"
,      min_size/1024/1024 "MIN_SIZE"
,      user_specified_size/1024/1024 "USER_SPECIFIED_SIZE"
,      last_oper_type "TYPE" 
FROM   v$sga_dynamic_components
;

look for the streams pool. There are several Metalink notes on this setting (including 316889.1, 102926.1 and 335516.1). The latter has a general recommandetion per RDBMS version:

• 11g: set STREAMS_POOL_SIZE to be greater or equal to 100 MB;
• 10gR2: set SGA_TARGET > 0 and STREAMS_POOL_SIZE=0 to enable autotuning of the Streams pool;
• 10gR1: use the STREAMS_POOL_SIZE init.ora parameter to configure the Streams memory allocation;

And of course you could use V$STREAMS_POOL_ADVICE to get advice for your specific situation.

Upgrade the JDK

A described here upgrading the JDK can also give a performance boost.

Because the growth in the number of messages that one of our customers is receiving on it’s Oracle ESB, they were looking into how to enhance it’s performance. Oracle came up with the following clues:

• Upgrade SOA Suite to a higher patch level
• Reduce logging (including instance tracking in ESB)
• Increase the number of listeners in ESB on Queues
• Turn off payload validation

In order to see what these could do for them we did some loadtesting. The upgrade to a higher patch level of SOA Suite was needed at least to get the ESB working correctly with the configured number of listeners. However because of some issues running Oracle Universal Installer there wasn’t any time left to verify that the patch resulted in increased performance.
For functional and application management reasons turning of logging was not considered an option at this stage.

Increase the number of listeners in ESB on Queues

set ESB listeners in console

Average response time

As expected the respons time increases at a certain point when the number of listeners is raised.

With 90% and max response time

From this experiments it can be concluded that the response time can significantly be reduced by setting the number of listeners of an ESB system to the appropriate level. The maximum respons time has can be decreased by over 50%. This has a significant impact on the availability of the services exposed using the ESB.

Turn off payload validation

Turn off payload validation

Response time

If you can change your service so payload validation at this point is no longer required, this is a great step in enhancing the Oracle ESB’s performance.

Async queue

One of our customers asked me exactly this question. They have an  Oracle ESB and it seemed that it could not handle all incoming requests. With the queues being a decoupling point between the incoming requests and the related transactions to the back office systems, its size can be an indication of just how busy the system is.

As I couldn’t find the answer using the Oracle Enterprise Manager Oracle Enterprise Manager and its MBeans, I started to look on the web for a tool. The tool I found and started to use was HermesJMS. This helps you interact with JMS providers making it easy to browse or search queues and topics, copy messages around and delete them.

HermesJMS screenshot

The HermesJMS requires Java 1.6. It has a clear installation guide installation guide and it is tested for multiple JMS providers. Besides the guide we needed for the Oracle AS there is also another blog describing the install and use of HermesJMS.

Using HermesJMS we were able to answer this customers question.