docs: public static Client createClient(ClientConfig config) {
          Client client = null;
          synchronized (ClientFactory.class) {
              if (!m_preserveResources && ++m_activeClientCount == 1) {
                  VoltLogger.startAsynchronousLogging();
                  EstTimeUpdater.start();
                  ReverseDNSCache.start();
              }
          }
          client = new ClientImpl(config);
          return client;
      }