eth: fix stuck when handleBlockBroadcast

eth/handler_eth.go

@@ -149,7 +149,9 @@ func (h *ethHandler) handleBlockBroadcast(peer *eth.Peer, packet *eth.NewBlockPa
 	log.Debug("handleBlockBroadcast", "peer", peer.ID(), "block", block.Number(), "hash", block.Hash())
 	h.blockFetcher.Enqueue(peer.ID(), block)
 	stats := h.chain.GetBlockStats(block.Hash())
+	blockFirstReceived := false
 	if stats.RecvNewBlockTime.Load() == 0 {
+		blockFirstReceived = true
 		stats.RecvNewBlockTime.Store(time.Now().UnixMilli())
 		addr := peer.RemoteAddr()
 		if addr != nil {
@@ -166,7 +168,9 @@ func (h *ethHandler) handleBlockBroadcast(peer *eth.Peer, packet *eth.NewBlockPa
 	// Update the peer's total difficulty if better than the previous
 	if _, td := peer.Head(); trueTD.Cmp(td) > 0 {
 		peer.SetHead(trueHead, trueTD)
-		h.chainSync.handlePeerEvent()
+		if blockFirstReceived {
+			h.chainSync.handlePeerEvent()
+		}
 	}
 	return nil
 }

eth/sync.go

@@ -79,7 +79,7 @@ type chainSyncOp struct {
 func newChainSyncer(handler *handler) *chainSyncer {
 	return &chainSyncer{
 		handler:     handler,
-		peerEventCh: make(chan struct{}),
+		peerEventCh: make(chan struct{}, 10),
 	}
 }
 
@@ -186,9 +186,9 @@ func (cs *chainSyncer) nextSyncOp() *chainSyncOp {
 	} else if op.td.Cmp(new(big.Int).Add(ourTD, common.Big2)) <= 0 { // common.Big2: difficulty of an in-turn block
 		// On BSC, blocks are produced much faster than on Ethereum.
 		// If the node is only slightly behind (e.g., 1 block), syncing is unnecessary.
-		// It's likely still processing broadcasted blocks or block hash announcements.
-		// In most cases, the node will catch up within 3 seconds.
-		time.Sleep(3 * time.Second)
+		// It's likely still processing broadcasted blocks(such as including a big tx) or block hash announcements.
+		// In most cases, the node will catch up within 2 seconds.
+		time.Sleep(2 * time.Second)
 
 		// Re-check local head to see if it has caught up
 		if _, latestTD := cs.modeAndLocalHead(); ourTD.Cmp(latestTD) < 0 {