JVM configuration

IBM® WebSphere® sMash Applications can be tuned by adjusting the JVM configuration

Adjusting JVM Parameters

The parameters used when starting the JVM of an application can be tuned by editing the zero.config configuration file of that application. To allow flexibility in the parameters used for different Java Runtimes, WebSphere sMash will use the list of values found at /config/ZSO/jvmArgs as a list of system properties. Then the values found under that configuration branch will be compared to the property returned by the JVM. If the JVM property contains the configured value, then the list of Strings found under that configuration leaf will added to the JVM arguments list. For example, the following configuration block will add the -Xmx64M argument to any JVM whose java.specification.version system property returns 1.6.

/config/zso/jvmargs/java.specification.version/1.6 += [
	"-Xmx64M"
]

The default configuration for JVM args is the following configuration segment:

/config/zso/jvmargs/java.vendor/IBM += [
	"-Xquickstart",
	"-Xshareclasses:name=Zero_%u"
]

# Marker for Windows IBM 1.6.0 SR1 JVM
/config/zso/jvmargs/java.fullversion/jvmwi3260-20080415 = [
	"-Xzero"
]

# Marker for Linux IBM 1.6.0 SR1 JVM
/config/zso/jvmargs/java.fullversion/jvmxi3260-20080415 = [
	"-Xzero"
]