Controlling the trace

You have several ways by which you can control the trace.

You can control the trace in several ways by using:
  • The -Xtrace options when launching the JVM, including trace trigger events
  • A trace properties file
  • com.ibm.jvm.Trace API
  • JVMTI and JVMRI from an external agent
Note:
  1. The specification of trace options is cumulative. Multiple -Xtrace options are accepted on the command line and they are processed in order starting with the option that is closest to the -Xtrace string. Each option adds to the previous options (and to the default options), as if they had all been specified in one long comma-separated list in a single option. This cumulative specification is consistent with the related -Xdump option processing.
  2. Some trace options are enabled by default. To disable the defaults, use the -Xtrace:none option.
  3. Many diagnostic tools start a JVM. When using the IBM_JAVA_OPTIONS environment variable to trace to a file, starting a diagnostic tool might overwrite the trace data generated from your application. Use the command-line tracing options or add %d, %p or %t to the trace file name to prevent this from happening. See -Xtrace for the appropriate trace option description.