sync/pipeline: using timer replace ticker (#477)

pkg/sync/pipeline/pipeline.go

@@ -174,12 +174,13 @@ func (p *Pipeline) mergeproc(mirror bool, index int, ch <-chan *message) {
 		closed  bool
 		count   int
 		inteval = p.config.Interval
-		oldTicker = true
+		timeout = false
 	)
 	if index > 0 {
 		inteval = xtime.Duration(int64(index) * (int64(p.config.Interval) / int64(p.config.Worker)))
 	}
-	ticker := time.NewTicker(time.Duration(inteval))
+	timer := time.NewTimer(time.Duration(inteval))
+	defer timer.Stop()
 	for {
 		select {
 		case m = <-ch:
@@ -193,12 +194,8 @@ func (p *Pipeline) mergeproc(mirror bool, index int, ch <-chan *message) {
 				break
 			}
 			continue
-		case <-ticker.C:
-			if oldTicker {
-				ticker.Stop()
-				ticker = time.NewTicker(time.Duration(p.config.Interval))
-				oldTicker = false
-			}
+		case <-timer.C:
+			timeout = true
 		}
 		name := p.name
 		process := count
@@ -215,8 +212,12 @@ func (p *Pipeline) mergeproc(mirror bool, index int, ch <-chan *message) {
 		_metricChanLen.Set(float64(len(ch)), name, strconv.Itoa(index))
 		_metricCount.Add(float64(process), name, strconv.Itoa(index))
 		if closed {
-			ticker.Stop()
 			return
 		}
+		if !timer.Stop() && !timeout {
+			<-timer.C
+			timeout = false
+		}
+		timer.Reset(time.Duration(p.config.Interval))
 	}
 }