docs: void recordDroppedRequest(String category) {
      AtomicLong counter = dropCounters.get(category);
      if (counter == null) {
        counter = dropCounters.putIfAbsent(category, new AtomicLong());
        if (counter == null) {
          counter = dropCounters.get(category);
        }
      }
      counter.getAndIncrement();
    }