refactor(eth/downloader): truncate peer id in sync logs

eth/downloader/downloader.go

@@ -340,7 +340,7 @@ func (d *Downloader) Synchronising() bool {
 // RegisterPeer injects a new download peer into the set of block source to be
 // used for fetching hashes and blocks from.
 func (d *Downloader) RegisterPeer(id string, version int, peer Peer) error {
-	logger := log.New("peer", id)
+	logger := peerLogger(id)
 	logger.Trace("Registering sync peer")
 	if err := d.peers.Register(newPeerConnection(id, version, peer, logger)); err != nil {
 		logger.Error("Failed to register sync peer", "err", err)
@@ -361,7 +361,7 @@ func (d *Downloader) RegisterLightPeer(id string, version int, peer LightPeer) e
 // the queue.
 func (d *Downloader) UnregisterPeer(id string) error {
 	// Unregister the peer from the active peer set and revoke any fetch tasks
-	logger := log.New("peer", id)
+	logger := peerLogger(id)
 	logger.Trace("Unregistering sync peer")
 	if err := d.peers.Unregister(id); err != nil {
 		logger.Warn("Failed to unregister sync peer", "err", err)

eth/downloader/peer.go

@@ -114,6 +114,15 @@ func (w *lightPeerWrapper) RequestNodeData([]common.Hash) error {
 	panic("RequestNodeData not supported in light client mode sync")
 }
 
+// peerLogger creates a logger tagged with the peer id, truncated to keep the
+// sync logs readable. Short ids used by the tests are left untouched.
+func peerLogger(id string) log.Logger {
+	if len(id) > 16 {
+		id = id[:16]
+	}
+	return log.New("peer", id)
+}
+
 // newPeerConnection creates a new downloader peer.
 func newPeerConnection(id string, version int, peer Peer, logger log.Logger) *peerConnection {
 	return &peerConnection{

eth/downloader/queue.go

@@ -708,37 +708,39 @@ func (q *queue) DeliverHeaders(id string, headers []*types.Header, headerProcCh
 	headerReqTimer.UpdateSince(request.Time)
 	delete(q.headerPendPool, id)
 
+	logger := peerLogger(id)
+
 	// Ensure headers can be mapped onto the skeleton chain
 	target := q.headerTaskPool[request.From].Hash()
 
 	accepted := len(headers) == MaxHeaderFetch
 	if accepted {
 		if headers[0].Number.Uint64() != request.From {
-			log.Trace("First header broke chain ordering", "peer", id, "number", headers[0].Number, "hash", headers[0].Hash(), request.From)
+			logger.Debug("First header broke chain ordering", "number", headers[0].Number, "hash", headers[0].Hash(), "expected", request.From)
 			accepted = false
 		} else if headers[len(headers)-1].Hash() != target {
-			log.Trace("Last header broke skeleton structure ", "peer", id, "number", headers[len(headers)-1].Number, "hash", headers[len(headers)-1].Hash(), "expected", target)
+			logger.Debug("Last header broke skeleton structure ", "number", headers[len(headers)-1].Number, "hash", headers[len(headers)-1].Hash(), "expected", target)
 			accepted = false
 		}
 	}
 	if accepted {
 		for i, header := range headers[1:] {
 			hash := header.Hash()
 			if want := request.From + 1 + uint64(i); header.Number.Uint64() != want {
-				log.Warn("Header broke chain ordering", "peer", id, "number", header.Number, "hash", hash, "expected", want)
+				logger.Warn("Header broke chain ordering", "number", header.Number, "hash", hash, "expected", want)
 				accepted = false
 				break
 			}
 			if headers[i].Hash() != header.ParentHash {
-				log.Warn("Header broke chain ancestry", "peer", id, "number", header.Number, "hash", hash)
+				logger.Warn("Header broke chain ancestry", "number", header.Number, "hash", hash)
 				accepted = false
 				break
 			}
 		}
 	}
 	// If the batch of headers wasn't accepted, mark as unavailable
 	if !accepted {
-		log.Trace("Skeleton filling not accepted", "peer", id, "from", request.From)
+		logger.Debug("Skeleton filling not accepted", "from", request.From)
 
 		miss := q.headerPeerMiss[id]
 		if miss == nil {
@@ -765,7 +767,7 @@ func (q *queue) DeliverHeaders(id string, headers []*types.Header, headerProcCh
 
 		select {
 		case headerProcCh <- process:
-			log.Trace("Pre-scheduled new headers", "peer", id, "count", len(process), "from", process[0].Number)
+			logger.Trace("Pre-scheduled new headers", "count", len(process), "from", process[0].Number)
 			q.headerProced += len(process)
 		default:
 		}