// to populate new values upon cache invalidation.
func (g *MetricsGroupV2) RegisterRead(read func(context.Context) []MetricV2) {
	g.metricsCache = cachevalue.NewFromFunc(g.cacheInterval,
		cachevalue.Opts{ReturnLastGood: true},
		func(ctx context.Context) ([]MetricV2, error) {
			if g.metricsGroupOpts.dependGlobalObjectAPI {
				objLayer := newObjectLayerFn()
				// Service not initialized yet