[fanout] Break worker from higher index

messaging/fanout.go

@@ -29,12 +29,13 @@ func (p *Pipeline) Start() {
 		for {
 			for _, c := range cs {
 				expectationWorkers := uint32(len(ch)/(MaxQueueSize/MaxWorkers)) + 1
+				runningWorker := atomic.LoadUint32(&running)
+				if c.index > runningWorker+1 || c.index > expectationWorkers {
+					break
+				}
 				select {
 				case val := <-ch:
-					runningWorker := atomic.LoadUint32(&running)
-					if c.index <= runningWorker || c.index <= expectationWorkers {
 					writer = c
-					}
 					if c.debug {
 						log.Info("Worker receiving", zap.Any("index", writer.index), zap.Any("running", runningWorker), zap.Any("no# workers", expectationWorkers))
 					}
@@ -43,6 +44,7 @@ func (p *Pipeline) Start() {
 			}
 			}
 		}
+	}
 
 	go distributeToChannels(p.chain, p.workers)
 }