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Prevents the Eclipse OpenJ9™ runtime environment from handling any internally or externally generated signals such as SIGSEGV and SIGABRT. Any signals that are raised are handled by the default operating system handlers, which you might want if you are using a debugger such as GDB or WinDbg to diagnose problems in JNI code.

Disabling signal handling in the OpenJ9 VM reduces performance by approximately 2-4%, depending on the application.

Note: Setting this option prevents dumps being generated by the OpenJ9 VM for signals such as SIGSEGV and SIGABRT, because the VM is no longer intercepting these signals. Do not use the -Xrs option with the following options:

An error is thrown if either of the options is enabled together with the -Xrs option. To resolve this error, one of the options should be disabled.




If you specify the sync parameter:

  • On AIX®, Linux®, macOS®, and z/OS® systems: Disables signal handling in the VM for SIGSEGV, SIGFPE, SIGBUS, SIGILL, SIGTRAP, and SIGABRT signals. However, the VM still handles the SIGQUIT and SIGTERM signals, among others.
  • On Windows™ systems: Hardware exceptions are not handled by the OpenJ9 VM when this option is specified. However, the Windows CTRL_BREAK_EVENT signal, triggered by the Ctrl-Break key combination, is still handled by the VM.

Linux and macOS systems always use the SIGUSR1 signal.

See also