code: public void maybePutThrottle(int nodeId) {
          if(!putThrottlers.containsKey(nodeId)) {
              putThrottlers.putIfAbsent(nodeId, new EventThrottler(perServerQPSLimit));
          }
          putThrottlers.get(nodeId).maybeThrottle(1);
      }
docs: Throttle put (repair) activity per server.
  
  @param nodeId The node for which to possibly throttle put activity.