void TenuredGeneration::collect(bool   full,
                                bool   clear_all_soft_refs,
                                size_t size,
                                bool   is_tlab) {

  {- -------------------------------------------
  (1) 
      ---------------------------------------- -}

      retire_alloc_buffers_before_full_gc();

  {- -------------------------------------------
  (1) OneContigSpaceCardGeneration::collect() を呼び出して GC 処理を行う.
      ---------------------------------------- -}

      OneContigSpaceCardGeneration::collect(full, clear_all_soft_refs,
                                            size, is_tlab);
    }