See bug for details. open webrev at http://cr.openjdk.java.net/~coleenp/8202164.01/webrev bug link https://bugs.openjdk.java.net/browse/JDK-8202164 Tested with runThese (lots of class unloading) for all the GCs and with mach5 hs-tier1 and 2. Thanks, Coleen