This option was added, with false default value, for JDK-7020042 "G1: Partially remove fix for 6994628", with hg 2283, 18-Feb-2011. The purpose is to, by default, disable reference processing during concurrent marking and at the end of remark, due to test failures.

The default for the option was changed from false to true for JDK-7009266: G1: assert(obj->is_oop_or_null(true )) failed: Error", with hg 2346, 7-April-2011. That change actually fixed the problem with G1 concurrent mark reference processing, by adding G1 read barriers for Reference referents.

The option has long since served its purpose, and is no longer needed.