code: private void tearDown() throws Exception {
      try {
        if (fileSystem != null) {
          fileSystem.delete(new Path(ROOT), true, true);
        }
      } finally {
        RPC.stopProxy(proxyClientProxyProtocol);
        IOUtils.cleanup(LOG, proxyTClientProxyProtocol, clientManager, fileSystem);
      }
    }
docs: Tears down clients after each benchmark