chore(perf): Pre-allocate where possible (enable prealloc linter) (#88952)

* chore(perf): Pre-allocate where possible (enable prealloc linter) Signed-off-by: Dave Henderson <dave.henderson@grafana.com> * fix TestAlertManagers_buildRedactedAMs Signed-off-by: Dave Henderson <dave.henderson@grafana.com> * prealloc a slice that appeared after rebase Signed-off-by: Dave Henderson <dave.henderson@grafana.com> --------- Signed-off-by: Dave Henderson <dave.henderson@grafana.com>
2024-06-14 14:16:36 -04:00
parent e53e6e7caa
commit 6262c56132
43 changed files with 211 additions and 140 deletions
@@ -332,12 +332,14 @@ func setupRedisLiveEngine(g *GrafanaLive, node *centrifuge.Node) error {
 	redisShardConfigs := []centrifuge.RedisShardConfig{
 		{Address: redisAddress, Password: redisPassword},
 	}
-	var redisShards []*centrifuge.RedisShard
+
+	redisShards := make([]*centrifuge.RedisShard, 0, len(redisShardConfigs))
 	for _, redisConf := range redisShardConfigs {
 		redisShard, err := centrifuge.NewRedisShard(node, redisConf)
 		if err != nil {
 			return fmt.Errorf("error connecting to Live Redis: %v", err)
 		}
+
 		redisShards = append(redisShards, redisShard)
 	}

@@ -348,6 +350,7 @@ func setupRedisLiveEngine(g *GrafanaLive, node *centrifuge.Node) error {
 	if err != nil {
 		return fmt.Errorf("error creating Live Redis broker: %v", err)
 	}
+
 	node.SetBroker(broker)

 	presenceManager, err := centrifuge.NewRedisPresenceManager(node, centrifuge.RedisPresenceManagerConfig{
@@ -357,7 +360,9 @@ func setupRedisLiveEngine(g *GrafanaLive, node *centrifuge.Node) error {
 	if err != nil {
 		return fmt.Errorf("error creating Live Redis presence manager: %v", err)
 	}
+
 	node.SetPresenceManager(presenceManager)
+
 	return nil
 }

@@ -116,17 +116,21 @@ func (s *Manager) handleDatasourceEvent(orgID int64, dsUID string, resubmit bool
 		s.mu.RUnlock()
 		return nil
 	}
-	var resubmitRequests []streamRequest
-	var waitChannels []chan struct{}
+
+	resubmitRequests := make([]streamRequest, 0, len(dsStreams))
+	waitChannels := make([]chan struct{}, 0, len(dsStreams))
 	for channel := range dsStreams {
 		streamCtx, ok := s.streams[channel]
 		if !ok {
 			continue
 		}
+
 		streamCtx.cancelFn()
+
 		waitChannels = append(waitChannels, streamCtx.CloseCh)
 		resubmitRequests = append(resubmitRequests, streamCtx.streamRequest)
 	}
+
 	s.mu.RUnlock()

 	// Wait for all streams to stop.