code: @Override
    public void afterDataFlush(PageServiceImpl tableService, 
                               int sequenceFlush)
    {
      super.afterDataFlush(tableService, sequenceFlush);
      
      tableService.compareAndSetBlobPage(this, _stub);
      
      ArrayList<TempBuffer> buffers = _buffers;
      _buffers = null;
  
      if (buffers != null) {
        for (TempBuffer buffer : buffers) {
          buffer.free();
        }
      }
    }
docs: Callback after the data has been written to the mmap, which allows for
  reads (but not necessarily fsynced.)