code: void delay(long alreadyElapsed) {
      recorder.recordValue(alreadyElapsed);
      if (distribution != null) {
        long nextPermitted = Math.round(distribution.sample() * 1000000000.0);
        if (nextPermitted > alreadyElapsed) {
          LockSupport.parkNanos(nextPermitted - alreadyElapsed);
        }
      }
    }
docs: Record the event elapsed time to the histogram and delay initiation of the next event based
  on the load distribution.