WIP: implement chain sync manager and concurrent sync

chain/sync.go

@@ -47,8 +47,6 @@ type Syncer struct {
 	// The known Genesis tipset
 	Genesis *types.TipSet
 
-	syncLock sync.Mutex
-
 	// TipSets known to be invalid
 	bad *BadBlockCache
 
@@ -57,12 +55,10 @@ type Syncer struct {
 
 	self peer.ID
 
+	syncLock  sync.Mutex
 	syncState SyncerState
 
-	// peer heads
-	// Note: clear cache on disconnects
-	peerHeads   map[peer.ID]*types.TipSet
-	peerHeadsLk sync.Mutex
+	syncmgr *SyncManager
 }
 
 func NewSyncer(sm *stmgr.StateManager, bsync *blocksync.BlockSync, self peer.ID) (*Syncer, error) {
@@ -87,8 +83,6 @@ func NewSyncer(sm *stmgr.StateManager, bsync *blocksync.BlockSync, self peer.ID)
 	}, nil
 }
 
-const BootstrapPeerThreshold = 1
-
 // InformNewHead informs the syncer about a new potential tipset
 // This should be called when connecting to new peers, and additionally
 // when receiving new blocks from the network
@@ -123,10 +117,8 @@ func (syncer *Syncer) InformNewHead(from peer.ID, fts *store.FullTipSet) {
 		return
 	}
 
-	syncer.peerHeadsLk.Lock()
-	syncer.peerHeads[from] = fts.TipSet()
-	syncer.peerHeadsLk.Unlock()
 	syncer.Bsync.AddPeer(from)
+	syncer.syncmgr.SetPeerHead(from, fts.TipSet())
 
 	bestPweight := syncer.store.GetHeaviestTipSet().Blocks()[0].ParentWeight
 	targetWeight := fts.TipSet().Blocks()[0].ParentWeight

chain/sync_manager.go

@@ -0,0 +1,87 @@
+package chain
+
+import (
+	"context"
+	"sync"
+
+	"github.com/filecoin-project/lotus/chain/types"
+	peer "github.com/libp2p/go-libp2p-peer"
+)
+
+const BootstrapPeerThreshold = 2
+
+type SyncFunc func(context.Context, *types.TipSet) error
+
+type SyncManager struct {
+	lk           sync.Mutex
+	peerHeads    map[peer.ID]*types.TipSet
+	bootstrapped bool
+
+	bspThresh int
+
+	syncTargets chan *types.TipSet
+
+	doSync func(context.Context, *types.TipSet) error
+}
+
+func NewSyncManager(sync SyncFunc) *SyncManager {
+	return &SyncManager{
+		peerHeads:   make(map[peer.ID]*types.TipSet),
+		syncTargets: make(chan *types.TipSet),
+		doSync:      sync,
+	}
+}
+
+func (sm *SyncManager) Start() {
+	for i := 0; i < syncWorkerCount; i++ {
+		go sm.syncWorker(i)
+	}
+}
+
+func (sm *SyncManager) SetPeerHead(p peer.ID, ts *types.TipSet) {
+	sm.lk.Lock()
+	defer sm.lk.Unlock()
+	sm.peerHeads[p] = ts
+
+	if !sm.bootstrapped {
+		spc := sm.syncedPeerCount()
+		if spc >= sm.bspThresh {
+			// Its go time!
+		}
+		log.Infof("sync bootstrap has %d peers", spc)
+		return
+	}
+
+}
+
+func (sm *SyncManager) syncWorker(id int) {
+	for {
+		select {
+		case ts, ok := sm.syncTargets:
+			if !ok {
+				log.Info("sync manager worker shutting down")
+				return
+			}
+
+			if err := sm.doSync(context.TODO(), ts); err != nil {
+				log.Errorf("sync error: %+v", err)
+			}
+		}
+	}
+}
+
+func (sm *SyncManager) syncedPeerCount() int {
+	var count int
+	for _, ts := range sm.peerHeads {
+		if ts.Height() > 0 {
+			count++
+		}
+	}
+	return count
+}
+
+func (sm *SyncManager) IsBootstrapped() bool {
+	sm.lk.Lock()
+	defer sm.lk.Unlock()
+	return sm.bootstrapped
+}