slight performance improvement

main.go

@@ -124,6 +124,7 @@ func (that *ProjectBackfeedManager) Do() {
 	//defer that.CloseItemChannel()
 	defer that.Cancel()
 
+	pipe := that.BackfeedRedis.Pipeline()
 	for {
 		select {
 		case <-that.Context.Done():
@@ -158,7 +159,6 @@ func (that *ProjectBackfeedManager) Do() {
 		}
 		now := time.Now()
 		resultMap := map[string]*redis.Cmd{}
-		pipe := that.BackfeedRedis.Pipeline()
 		lastTS := make([]any, 0, len(keyMap)*2)
 		for key := range keyMap {
 			lastTS = append(lastTS, key)
@@ -641,10 +641,18 @@ func (that *GlobalBackfeedManager) HandleDump(res http.ResponseWriter, req *http
 	}
 	tarWriter := tar.NewWriter(res)
 	defer tarWriter.Close()
+	pipe := that.BackfeedRedis.Pipeline()
 	for _, key := range keys {
 		cursor := int64(0)
 		for i := 0; ; i++ {
-			rawRes, err := that.BackfeedRedis.Do(req.Context(), "bf.scandump", key, cursor).Result()
+			rawResResult := pipe.Do(req.Context(), "bf.scandump", key, cursor)
+			tsStringResult := that.BackfeedRedis.HGet(req.Context(), ":last_ts", key)
+			_, err := pipe.Exec(req.Context())
+			if err != nil && err != redis.Nil {
+				WriteResponse(res, http.StatusInternalServerError, err)
+				return
+			}
+			rawRes, err := rawResResult.Result()
 			if err != nil && err != redis.Nil {
 				WriteResponse(res, http.StatusInternalServerError, err)
 				return
@@ -674,7 +682,7 @@ func (that *GlobalBackfeedManager) HandleDump(res http.ResponseWriter, req *http
 			chunk := []byte(chunkString)
 
 			lastAccess := time.Time{}
-			tsString, err := that.BackfeedRedis.HGet(req.Context(), ":last_ts", key).Result()
+			tsString, err := tsStringResult.Result()
 			if err == nil && tsString != "" {
 				ts, err := strconv.ParseInt(tsString, 10, 64)
 				if err == nil {