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Controls processing of the -Xlog option.


Setting Effect Default
-XX:+LegacyXlogOption Enable legacy -Xlog behavior
-XX:-LegacyXlogOption Process -Xlog requests for GC logging yes


From Eclipse OpenJ9™ 0.24.0, the -Xlog option is replaced by the -Xsyslog option. The -XX:[+|-]LegacyXlogOption controls how the -Xlog option is processed.

  • When -XX:-LegacyXlogOption is set, the -Xlog option is recognized only when a form of this option is run that requests garbage collection (GC) logging (for example, -Xlog:gc[:stderr|:file=<filename>]). For more information, see -Xlog.
  • When -XX:+LegacyXlogOption is set, the legacy -Xlog behavior is enabled. When enabled, the option is equivalent to the -Xsyslog option. That is, the -Xlog option can be used with the parameters documented in -Xsyslog.