@Override
  public CallQueueInfo getCallQueueInfo() {
    String queueName = "Master Fifo Queue";

    HashMap<String, Long> methodCount = new HashMap<>();
    HashMap<String, Long> methodSize = new HashMap<>();

    CallQueueInfo callQueueInfo = new CallQueueInfo();
    callQueueInfo.setCallMethodCount(queueName, methodCount);
    callQueueInfo.setCallMethodSize(queueName, methodSize);

    updateMethodCountAndSizeByQueue(executor.getQueue(), methodCount, methodSize);
    updateMethodCountAndSizeByQueue(rsReportExecutor.getQueue(), methodCount, methodSize);

    return callQueueInfo;
  }
Set RSReport requests handlers count when masters use MasterFifoRpcScheduler. The default value
is half of "hbase.regionserver.handler.count" value, but at least 1. The other handlers count
is "hbase.regionserver.handler.count" value minus RSReport handlers count, but at least 1 too.
hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/MasterFifoRpcScheduler.java