Adjusting the JVM Heap Size

Java options, such as JVM heap size and VM mode, used by the WebLogic server are stored in your WebLogic domain's setEnv script, stored in:

PIA_HOME\webserv\peoplesoft\bin

These options are specified in the script using the JAVA_OPTIONS_OSplatform environment variable. If you need to adjust any of the Java options, including changing the JVM heap size, you must manually edit the script.

The Microsoft Windows setEnv.cmd script contains the following default setting:

SET JAVA_OPTIONS_WIN=-jrockit -XnoOpt -Xms512m -Xmx512m 
-Dtoplink.xml.platform=oracle.toplink.platform.xml.jaxp.JAXPPlatform

The UNIX standard setEnv.sh script contains the following default settings for supported Linux and UNIX platforms:

JAVA_OPTIONS_AIX="-Xms128m -Xmx256m -Dtoplink.xml.platform
=oracle.toplink.platform.xml.jaxp.JAXPPlatform 
-Dcom.sun.xml.namespace.QName.useCompatibleSerialVersionUID=1.0"
 
JAVA_OPTIONS_HPUX="-Xms256m -Xmx256m -XX:MaxPermSize=256m 
-Dtoplink.xml.platform=oracle.toplink.platform.xml.jaxp.JAXPPlatform 
-Dcom.sun.xml.namespace.QName.useCompatibleSerialVersionUID=1.0"
 
JAVA_OPTIONS_LINUX="-jrockit -XnoOpt -Xms512m -Xmx512m 
-Dtoplink.xml.platform=oracle.toplink.platform.xml.jaxp.JAXPPlatform 
-Dcom.sun.xml.namespace.QName.useCompatibleSerialVersionUID=1.0"
 
JAVA_OPTIONS_SOLARIS="-Xms256m -Xmx256m -XX:MaxPermSize=256m 
-Dtoplink.xml.platform=oracle.toplink.platform.xml.jaxp.JAXPPlatform 
-Dcom.sun.xml.namespace.QName.useCompatibleSerialVersionUID=1.0"

You modify the Xms parameter to adjust minimum heap size, and modify the Xmx parameter to adjust maximum heap size. For most operating systems, the minimum and maximum values of the heap size are equal, which is recommended for better performance.

In a multi-server domain, the platform-specific versions of the JAVA_OPTIONS environment variable that appear in the setEnv script apply only to managed servers. The administration server doesn't use any of these variables, but it assumes default JVM heap size values of "-Xms256m -Xmx256m".

To adjust the JVM heap size for the administration server, add the environment variable JAVA_OPTIONS_ADMINSERVER following the last entry for JAVA_OPTIONS_OSplatform, and set it to your required minimum and maximum values, for example:

JAVA_OPTIONS_ADMINSERVER="-Xms128m -Xmx256m"