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Tune a workload management configuration

We can set values for several workload management client properties to tune the behavior of the workload management runtime.

You set the properties as command-line arguments for the JVM process in which the workload management client is running.

Caution: Set the values of these properties only in response to problems that you encounter. In most cases, we do not need to change the values. If workload management is functioning correctly, changing the values can produce undesirable results.

To change the property values, we can use the JVM page of the console or wsadmin commands. In cases such as where a servlet is a client to an enterprise bean, use the administrative console page for the application server where the servlet is running to configure the properties. The following steps describe how to change the values using the console.

1. Access the Java Virtual Machine page in the console.

2. On the Java Virtual Machine page, specify one or more of the following command-line arguments in the Generic JVM arguments field:

   • -Dcom.ibm.CORBA.RequestTimeout=timeout_interval

     If the application is experiencing problems with timeouts, this argument changes the value for the com.ibm.CORBA.RequestTimeout property, which specifies the timeout period for responding to requests sent from the client. This argument uses the -D option. timeout_interval is the timeout period in seconds. If the network experiences extreme latency, specify a large value to prevent timeouts. If we specify a value that is too small, an application server that participates in workload management can time out before it receives a response.

     Avoid trouble: Be careful specifying this property; it has no recommended value. Set it only if the application is experiencing problems with timeouts.gotcha

   • -Dcom.ibm.websphere.wlm.unusable.interval=interval

     If the workload management state of the client is refreshing too soon or too late, this argument changes the value for the com.ibm.websphere.wlm.unusable.interval property, which specifies the time interval that the workload management client runtime waits after it marks a server as unavailable before it attempts to contact the server again. This argument uses the -D option. interval is the time in seconds between attempts. The default value is 300 seconds. If the property is set to a large value, the server is marked as unavailable for a long period of time. This prevents the workload management refresh protocol from refreshing the workload management state of the client until after the time period has ended.

3. Click OK and Save to save the configuration changes.

4. Stop the application server and then restart the application server.

Related tasks

Balancing workloads

Configure the JVM