The preferred way to control trace is through trace options that you specify by using the -Xtrace option on the launcher command line, or by using the IBM_JAVA_OPTIONS environment variable.
Some trace options have the form <name> and others are of the form <name>=<value>, where <name> is case-sensitive. Except where stated, <value> is not case-sensitive; the exceptions to this rule are file names on some platforms, class names, and method names.
methods={java/lang/*,com/ibm/*}
java -Xgcpolicy:metronome -Xtrace:<name>,<another_name>=<value> HelloWorld
java -Xgcpolicy:metronome -Xtrace:none=all
If you specify other tracepoints without specifying -Xtrace:none, the tracepoints are added to the default set.
set IBM_JAVA_OPTIONS=-Xtrace:<name>,<another_name>=<value>or
export IBM_JAVA_OPTIONS=-Xtrace:<name>,<another_name>=<value>
java -Xgcpolicy:metronome "-Xtrace:<name>,<another_name>=<value>" HelloWorldFor more information, see the manual for your shell.