code: @Override
    public void flush()
    {
      // server/021g
      _logWriterQueue.wake();
      
      waitForFlush(10);
      
      try {
        super.flush();
      } catch (IOException e) {
        log.log(Level.FINER, e.toString(), e);
      }
    }
docs: must be synchronized by _bufferLock.