Administer Object Request Brokers

An Object Request Broker (ORB) uses the Internet InterORB Protocol (IIOP) to manage the interaction between clients and servers. The ORB enables clients to make requests and receive responses from servers in a network-distributed environment.

Each client request uses a client-side ORB and a server-side ORB. It is important that the ORB properties be set for both sides as necessary. Clients use the ORB to locate objects in the server-side network and call operations on those objects as if the remote objects were located in the same running process as the client. The client calls an operation on a local object, known as a stub. The client-side ORB creates an IIOP request that contains the operation and any required parameters, and sends the request to the network. The server-side ORB receives the IIOP request, locates the target object, invokes the requested operation, and returns the results to the client. The client-side ORB demarshals the returned results and passes the result to the stub, which returns to the client application.

WebSphere Application Server uses an ORB to manage communication between client applications and server applications as well as communication among product components. During product installation, default property values are set when the ORB is initialized. These properties control the run-time behavior of the ORB and can also affect the behavior of product components that are tightly integrated with the ORB, such as security. WebSphere Application Server does not support the use of multiple ORB instances.

When you start WebSphere Application Server, the application server initializes the Java Object Request Broker (ORB) service. When the ORB is initialized, a set of default properties are set. These properties control the runtime behavior of the ORB, and can affect the behavior of product components that are integrated with the ORB, such as security.

After an ORB instance is established in a process, changes to ORB properties do not affect the behavior of the running ORB instance. For the changes to take effect, stop and restart the process.

Under most circumstances, you do not need to modify the default properties. To change the properties, follow these steps:

  1. Start the administrative console.
  2. In the topology tree, expand Servers and click Application Servers
  3. Click the name of your application server.
  4. On the application server page, click ORB Service.
  5. You can modify the general ORB properties on the ORB Service page. To make changes to thread pool settings, click Thread Pool under Additional Properties. For help with ORB settings, see Object Request Broker service settings. Link outside Information Center

    Note: The Request timeout setting can affect the performance of the ORB. If you want to change the timeout setting, see Object Request Broker tuning guidelines.

  6. To enable and configure the Logical Pool Distribution (LPD) mechanism, click Custom Properties. For more information about LPD, see Logical Pool Distribution.
  7. After you make your changes, click OK.
  8. Save the configuration.
  9. Restart the server so that the changes take effect.

These topics provide additional information about using the ORB service:

Logical Pool Distribution
Logical Pool Distribution can improve performance in situations where client requests have varying execution times. This topic provides information about

Object Request Broker service custom properties
This topic describes the custom properties that you can set for the ORB service and how to set them.

Determine the ORB message size
The ORB breaks messages into fragments to send over the ORB connection. This topic describes how to determine the size of the messages that are transferred over the ORB connection and the number of fragments required to send the messages.

Object Request Broker tuning guidelines
This topic provides information to help you tune ORB performance.