Setting the survivor ratio

Survivor ratio determines the size of the survivor spaces, as a ratio of the total new space, and can be tuned to ensure that the survivor spaces are large enough to hold all the objects that survive "young" garbage collections.

Getting ready

This recipe assumes you are using the HotSpot JVM. JRockit manages memory differently and does not have an equivalent parameter.

For more details, refer to the Getting ready section of the Setting the new size recipe.

How to do it...

To set the heap survivor ratio for the HotSpot JVM, 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:

   SET DEFAULT_MEM_ARGS=%DEFAULT_MEM_ARGS% -XX:PermSize=128m –XX:MaxPermSize=512m
   SET PORT_MEM_ARGS=%PORT_MEM_ARGS% -XX:PermSize=128m –XX:MaxPermSize=512m

   Or the equivalent on a Linux or a Unix system.

4. Edit the previous lines to add...