[fanout] Break worker from higher index

messaging/fanout.go

@@ -29,18 +29,20 @@ 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)
+					writer = c
-					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))
 					}
 					go writer.stream(val)
 				}
 			}
+			}
 		}
 	}