code: public void setDiscarding()
      {
          state = state.transition(LifeCycle.DISCARDING);
          // mark the memory owned by this allocator as reclaiming
          onHeap.markAllReclaiming();
          offHeap.markAllReclaiming();
      }
docs: Mark this allocator reclaiming; this will permit any outstanding allocations to temporarily
  overshoot the maximum memory limit so that flushing can begin immediately