les: improved header fetcher and server statistics

Author: zsfelfoldi

les/fetcher.go

@@ -24,10 +24,8 @@ import (
 	"math/big"
 	"net"
 	"sync"
-	"time"
 
 	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/common/mclock"
 	"github.com/ethereum/go-ethereum/core"
 	"github.com/ethereum/go-ethereum/core/state"
 	"github.com/ethereum/go-ethereum/core/types"
@@ -60,7 +58,7 @@ const (
 	MaxHeaderProofsFetch = 64  // Amount of merkle proofs to be fetched per retrieval request
 	MaxTxSend            = 64  // Amount of transactions to be send per request
 
-	disableClientRemovePeer = true
+	disableClientRemovePeer = false
 )
 
 // errIncompatibleConfig is returned if the requested protocols and configs are
@@ -157,44 +155,27 @@ func NewProtocolManager(chainConfig *params.ChainConfig, lightSync bool, network
 			Length:  ProtocolLengths[i],
 			Run: func(p *p2p.Peer, rw p2p.MsgReadWriter) error {
 				var entry *poolEntry
+				peer := manager.newPeer(int(version), networkId, p, rw)
 				if manager.serverPool != nil {
 					addr := p.RemoteAddr().(*net.TCPAddr)
-					entry = manager.serverPool.connect(p.ID(), addr.IP, uint16(addr.Port))
+					entry = manager.serverPool.connect(peer, addr.IP, uint16(addr.Port))
 					if entry == nil {
 						return fmt.Errorf("unwanted connection")
 					}
 				}
-				peer := manager.newPeer(int(version), networkId, p, rw)
 				peer.poolEntry = entry
 				select {
 				case manager.newPeerCh <- peer:
 					manager.wg.Add(1)
 					defer manager.wg.Done()
-					start := mclock.Now()
 					err := manager.handle(peer)
 					if entry != nil {
-						connTime := time.Duration(mclock.Now() - start)
-						stopped := false
-						select {
-						case <-manager.quitSync:
-							stopped = true
-						default:
-						}
-						//fmt.Println("connTime", peer.id, connTime, stopped, err)
-						quality := float64(1)
-						setQuality := true
-						if connTime < time.Minute*10 {
-							quality = 0
-							if stopped {
-								setQuality = false
-							}
-						}
-						manager.serverPool.disconnect(entry, quality, setQuality)
+						manager.serverPool.disconnect(entry)
 					}
 					return err
 				case <-manager.quitSync:
 					if entry != nil {
-						manager.serverPool.disconnect(entry, 0, false)
+						manager.serverPool.disconnect(entry)
 					}
 					return p2p.DiscQuitting
 				}
@@ -224,7 +205,6 @@ func NewProtocolManager(chainConfig *params.ChainConfig, lightSync bool, network
 		manager.downloader = downloader.New(downloader.LightSync, chainDb, manager.eventMux, blockchain.HasHeader, nil, blockchain.GetHeaderByHash,
 			nil, blockchain.CurrentHeader, nil, nil, nil, blockchain.GetTdByHash,
 			blockchain.InsertHeaderChain, nil, nil, blockchain.Rollback, removePeer)
-		manager.fetcher = newLightFetcher(manager)
 	}
 
 	if odr != nil {
@@ -254,10 +234,12 @@ func (pm *ProtocolManager) removePeer(id string) {
 	glog.V(logger.Debug).Infof("LES: unregister peer %v", id)
 	if pm.lightSync {
 		pm.downloader.UnregisterPeer(id)
-		pm.odr.UnregisterPeer(peer)
 		if pm.txrelay != nil {
 			pm.txrelay.removePeer(id)
 		}
+		if pm.fetcher != nil {
+			pm.fetcher.removePeer(peer)
+		}
 	}
 	if err := pm.peers.Unregister(id); err != nil {
 		glog.V(logger.Error).Infoln("Removal failed:", err)
@@ -276,8 +258,10 @@ func (pm *ProtocolManager) Start(srvr *p2p.Server) {
 	lesTopic := discv5.Topic("LES@" + common.Bytes2Hex(pm.blockchain.Genesis().Hash().Bytes()[0:8]))
 	if pm.lightSync {
 		// start sync handler
-		if srvr != nil {
+		if srvr != nil { // srvr is nil during testing
 			pm.serverPool = newServerPool(pm.chainDb, []byte("serverPool/"), srvr, lesTopic, pm.quitSync, &pm.wg)
+			pm.odr.serverPool = pm.serverPool
+			pm.fetcher = newLightFetcher(pm)
 		}
 		go pm.syncer()
 	} else {
@@ -369,12 +353,17 @@ func (pm *ProtocolManager) handle(p *peer) error {
 			requestHeadersByHash, requestHeadersByNumber, nil, nil, nil); err != nil {
 			return err
 		}
-		pm.odr.RegisterPeer(p)
 		if pm.txrelay != nil {
 			pm.txrelay.addPeer(p)
 		}
 
-		pm.fetcher.notify(p, nil)
+		p.lock.Lock()
+		head := p.headInfo
+		p.lock.Unlock()
+		if pm.fetcher != nil {
+			pm.fetcher.addPeer(p)
+			pm.fetcher.announce(p, head)
+		}
 
 		if p.poolEntry != nil {
 			pm.serverPool.registered(p.poolEntry)
@@ -460,7 +449,9 @@ func (pm *ProtocolManager) handleMsg(p *peer) error {
 			return errResp(ErrDecode, "%v: %v", msg, err)
 		}
 		glog.V(logger.Detail).Infoln("AnnounceMsg:", req.Number, req.Hash, req.Td, req.ReorgDepth)
-		pm.fetcher.notify(p, &req)
+		if pm.fetcher != nil {
+			go pm.fetcher.announce(p, &req)
+		}
 
 	case GetBlockHeadersMsg:
 		glog.V(logger.Debug).Infof("<=== GetBlockHeadersMsg from peer %v", p.id)
@@ -558,7 +549,7 @@ func (pm *ProtocolManager) handleMsg(p *peer) error {
 			return errResp(ErrDecode, "msg %v: %v", msg, err)
 		}
 		p.fcServer.GotReply(resp.ReqID, resp.BV)
-		if pm.fetcher.requestedID(resp.ReqID) {
+		if pm.fetcher != nil && pm.fetcher.requestedID(resp.ReqID) {
 			pm.fetcher.deliverHeaders(p, resp.ReqID, resp.Headers)
 		} else {
 			err := pm.downloader.DeliverHeaders(p.id, resp.Headers)

les/handler.go

@@ -25,6 +25,7 @@ import (
 	"math/big"
 	"sync"
 	"testing"
+	"time"
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core"
@@ -334,3 +335,13 @@ func (p *testPeer) handshake(t *testing.T, td *big.Int, head common.Hash, headNu
 func (p *testPeer) close() {
 	p.app.Close()
 }
+
+type testServerPool peer
+
+func (p *testServerPool) selectPeer(func(*peer) (bool, uint64)) *peer {
+	return (*peer)(p)
+}
+
+func (p *testServerPool) adjustResponseTime(*poolEntry, time.Duration, bool) {
+
+}

les/helper_test.go

@@ -37,22 +37,26 @@ var (
 // peerDropFn is a callback type for dropping a peer detected as malicious.
 type peerDropFn func(id string)
 
+type odrPeerSelector interface {
+	selectPeer(func(*peer) (bool, uint64)) *peer
+	adjustResponseTime(*poolEntry, time.Duration, bool)
+}
+
 type LesOdr struct {
 	light.OdrBackend
 	db           ethdb.Database
 	stop         chan struct{}
 	removePeer   peerDropFn
 	mlock, clock sync.Mutex
 	sentReqs     map[uint64]*sentReq
-	peers        *odrPeerSet
+	serverPool   odrPeerSelector
 	lastReqID    uint64
 }
 
 func NewLesOdr(db ethdb.Database) *LesOdr {
 	return &LesOdr{
 		db:       db,
 		stop:     make(chan struct{}),
-		peers:    newOdrPeerSet(),
 		sentReqs: make(map[uint64]*sentReq),
 	}
 }
@@ -77,16 +81,6 @@ type sentReq struct {
 	answered chan struct{} // closed and set to nil when any peer answers it
 }
 
-// RegisterPeer registers a new LES peer to the ODR capable peer set
-func (self *LesOdr) RegisterPeer(p *peer) error {
-	return self.peers.register(p)
-}
-
-// UnregisterPeer removes a peer from the ODR capable peer set
-func (self *LesOdr) UnregisterPeer(p *peer) {
-	self.peers.unregister(p)
-}
-
 const (
 	MsgBlockBodies = iota
 	MsgCode
@@ -142,29 +136,26 @@ func (self *LesOdr) requestPeer(req *sentReq, peer *peer, delivered, timeout cha
 
 	select {
 	case <-delivered:
-		servTime := uint64(mclock.Now() - stime)
-		self.peers.updateTimeout(peer, false)
-		self.peers.updateServTime(peer, servTime)
+		if self.serverPool != nil {
+			self.serverPool.adjustResponseTime(peer.poolEntry, time.Duration(mclock.Now()-stime), false)
+		}
 		return
 	case <-time.After(softRequestTimeout):
 		close(timeout)
-		if self.peers.updateTimeout(peer, true) {
-			self.removePeer(peer.id)
-		}
 	case <-self.stop:
 		return
 	}
 
 	select {
 	case <-delivered:
-		servTime := uint64(mclock.Now() - stime)
-		self.peers.updateServTime(peer, servTime)
-		return
 	case <-time.After(hardRequestTimeout):
-		self.removePeer(peer.id)
+		go self.removePeer(peer.id)
 	case <-self.stop:
 		return
 	}
+	if self.serverPool != nil {
+		self.serverPool.adjustResponseTime(peer.poolEntry, time.Duration(mclock.Now()-stime), true)
+	}
 }
 
 // networkRequest sends a request to known peers until an answer is received
@@ -193,7 +184,13 @@ func (self *LesOdr) networkRequest(ctx context.Context, lreq LesOdrRequest) erro
 
 	exclude := make(map[*peer]struct{})
 	for {
-		if peer := self.peers.bestPeer(lreq, exclude); peer == nil {
+		var p *peer
+		if self.serverPool != nil {
+			p = self.serverPool.selectPeer(func(p *peer) (bool, uint64) {
+				return true, p.fcServer.CanSend(lreq.GetCost(p))
+			})
+		}
+		if p == nil {
 			select {
 			case <-ctx.Done():
 				return ctx.Err()
@@ -202,17 +199,17 @@ func (self *LesOdr) networkRequest(ctx context.Context, lreq LesOdrRequest) erro
 			case <-time.After(retryPeers):
 			}
 		} else {
-			exclude[peer] = struct{}{}
+			exclude[p] = struct{}{}
 			delivered := make(chan struct{})
 			timeout := make(chan struct{})
 			req.lock.Lock()
-			req.sentTo[peer] = delivered
+			req.sentTo[p] = delivered
 			req.lock.Unlock()
 			reqWg.Add(1)
-			cost := lreq.GetCost(peer)
-			peer.fcServer.SendRequest(reqID, cost)
-			go self.requestPeer(req, peer, delivered, timeout, reqWg)
-			lreq.Request(reqID, peer)
+			cost := lreq.GetCost(p)
+			p.fcServer.SendRequest(reqID, cost)
+			go self.requestPeer(req, p, delivered, timeout, reqWg)
+			lreq.Request(reqID, p)
 
 			select {
 			case <-ctx.Done():