@Test
  public void testStopRegionServer() {
    conn.getAdmin().stopRegionServer(ServerName.valueOf("rs", 16010, 12345)).join();
    verify(adminStub, times(1)).stopServer(assertPriority(HIGH_QOS), any(StopServerRequest.class),
      any());
  }
Confirm that we will set the priority in {@link HBaseRpcController} for several admin operations.
hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestAsyncAdminRpcPriority.java