private static boolean CAS( long[] A, int idx, long old, long nnn ) {
      return UNSAFE.compareAndSwapLong( A, rawIndex(A,idx), old, nnn );
    }
Return the internal counter striping factor.  Useful for diagnosing
performance problems.
jctools-core/src/main/java/org/jctools/maps/ConcurrentAutoTable.java