-Xmixed           mixed mode execution (default)
    -Xint             interpreted mode execution only
    -Xbootclasspath:<directories and zip/jar files separated by :>
                      set search path for bootstrap classes and resources
    -Xbootclasspath/a:<directories and zip/jar files separated by :>
                      append to end of bootstrap class path
    -Xbootclasspath/p:<directories and zip/jar files separated by :>
                      prepend in front of bootstrap class path
    -Xnoclassgc       disable class garbage collection
    -Xincgc           enable incremental garbage collection
    -Xverbosegc<options>
                      output Java heap information during garbage collection
                      (use -Xverbosegc:help for options)
    -Xbatch           disable background compilation
    -Xms<size>        set initial Java heap size. example: -Xms32m
    -Xmx<size>        set maximum Java heap size. example: -Xmx64m
    -Xmn<size>        set new generation Java heap size. example: -Xmn64m
    -Xss              set Java thread stack size. example: -Xss128k
    -Xprof            output cpu profiling data
    -Xeprof:<options> output profile data for HPjmeter
                      (use -Xeprof:help for options)
    -Xrunhprof[:help]|[:<option>=<value>, ...]
                      perform JVMPI heap, cpu, or monitor profiling
    -Xdebug           enable remote debugging
    -Xfuture          enable strictest checks, anticipating future default
    -Xrs              reduce use of OS signals by Java/VM (see documentation)
    -Xprep<options>   use dynamic bytecode preprocessor for loaded classes
    -XdoCloseWithReadPending
                      enable non-blocking close operations
    -XUseSIGUSR2      use SIGUSR2 for vm signals instead of SIGUSR1
    -Xnocatch         disable the catch all signal handler

The -X options are non-standard and subject to change without notice.