return err
			}
			states[idx] = st
			return nil
		}, idx, *client.host)
	}

	return states, ng.Wait()
}

// StartProfiling - start profiling on remote peers, by initiating a remote RPC.
func (sys *NotificationSys) StartProfiling(ctx context.Context, profiler string) []NotificationPeerErr {
	ng := WithNPeers(len(sys.peerClients))
	for idx, client := range sys.peerClients {
		if client == nil {

	// Start profiling on remote servers.
	for _, profiler := range profiles {
		// Limit start time to max 10s.
		ctx, cancel := context.WithTimeout(ctx, 10*time.Second)
		globalNotificationSys.StartProfiling(ctx, profiler)
		// StartProfiling blocks, so we can cancel now.
		cancel()

		// Start profiling locally as well.
		prof, err := startProfiler(profiler)
		if err == nil {
			globalProfiler[profiler] = prof
		}