code: int refreshAndGetMax() {
  		int max = 0;
  
  		for (ResultSubpartition part : partition.getAllPartitions()) {
  			int size = part.unsynchronizedGetNumberOfQueuedBuffers();
  			max = Math.max(max, size);
  		}
  
  		return max;
  	}
docs: Iterates over all sub-partitions and collects the maximum number of queued buffers in a
  sub-partition in a best-effort way.
  
  @return maximum number of queued buffers per sub-partition