diff --git a/miner/miningmgr.go b/miner/miningmgr.go
index 436f336..89ba094 100644
--- a/miner/miningmgr.go
+++ b/miner/miningmgr.go
@@ -134,7 +134,6 @@ func (m *Miner) winCountInRound(ctx context.Context, account string, mAddr addre
 
 	var nullRounds abi.ChainEpoch
 	if epoch > ts.Height() {
-		log.Infof("winCountInRound had null round, expect epoch %d, actual epoch %d", epoch, ts.Height())
 		nullRounds = epoch - ts.Height()
 	}
 	round := ts.Height() + nullRounds + 1
@@ -194,8 +193,10 @@ func (m *Miner) CountWinners(ctx context.Context, addrs []address.Address, start
 	}
 	m.lkWPP.Unlock()
 
+	controlChan := make(chan struct{}, 100)
 	if len(minerWpps) > 0 {
 		sign := m.signerFunc(ctx, m.gatewayNode)
+
 		wg.Add(len(minerWpps))
 		for addr, wpp := range minerWpps {
 			tAddr := addr
@@ -209,7 +210,12 @@ func (m *Miner) CountWinners(ctx context.Context, addrs []address.Address, start
 				for epoch := start; epoch <= end; epoch++ {
 					wgWin.Add(1)
 					go func(epoch abi.ChainEpoch) {
-						defer wgWin.Done()
+						defer func() {
+							wgWin.Done()
+							<-controlChan
+						}()
+
+						controlChan <- struct{}{}
 
 						winner, err := m.winCountInRound(ctx, tWpp.account, tAddr, sign, epoch)
 						if err != nil {
@@ -233,6 +239,7 @@ func (m *Miner) CountWinners(ctx context.Context, addrs []address.Address, start
 		}
 		wg.Wait()
 	}
+	close(controlChan)
 
 	return res, nil
 }
diff --git a/miner/util.go b/miner/util.go
index b8306c9..21b4116 100644
--- a/miner/util.go
+++ b/miner/util.go
@@ -45,7 +45,8 @@ func IsRoundWinner(
 	miner address.Address,
 	brand types.BeaconEntry,
 	mbi *types.MiningBaseInfo,
-	sign SignFunc) (*types.ElectionProof, error) {
+	sign SignFunc,
+) (*types.ElectionProof, error) {
 
 	buf := new(bytes.Buffer)
 	if err := miner.MarshalCBOR(buf); err != nil {