Setting the new size

Getting the new size correct is probably the single biggest thing that can be done to prevent poor garbage collection performance.

Getting ready

This recipe assumes that you are starting WebLogic using the startWebLogic or startManagedWebLogic scripts. If you are using the node manager or some other mechanism, simply apply the startup parameter to the relevant place. You will need the file system permissions to edit the WebLogic start scripts for this recipe.

This recipe assumes that you are using the HotSpot JVM, and if you are using JRockit, see the There's more… section of this recipe, for the parameter you need.

How to do it...

To set the HotSpot heap memory's new size, perform the following steps:

1. Navigate to the domain's bin directory:

   cd %MIDDLEWARE_HOME%/user_projects/domains/soa_domain/bin

2. Open the setSOADomainEnv.cmd or setSOADomainEnv.sh script in a text editor.

3. Locate the following lines for a Windows system:

   SET DEFAULT_MEM_ARGS=%DEFAULT_MEM_ARGS% -XX:PermSize=128m...