code: public void addNano(long nanos)
      {
          // convert to microseconds. 1 millionth
          latency.update(nanos, TimeUnit.NANOSECONDS);
          totalLatency.inc(nanos / 1000);
          totalLatencyHistogram.add(nanos / 1000);
          recentLatencyHistogram.add(nanos / 1000);
          for(LatencyMetrics parent : parents)
          {
              parent.addNano(nanos);
          }
      }
docs: takes nanoseconds *