SupportMapFragment loads slowly the first time

gistfile1.java

private SupportMapFragment supportMapFragment;

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.fragment_map, container, false);
    
    supportMapFragment = SupportMapFragment.newInstance();
    getChildFragmentManager().beginTransaction().replace(R.id.map_container, supportMapFragment).commit();

    return view;
}

@Override
public void onViewCreated(View view, Bundle savedInstanceState) {
    super.onViewCreated(view, savedInstanceState);
}

@Override
public void onStart() {
    super.onStart();

    final GoogleMap googleMap = supportMapFragment.getMap();
    
    ...
}