added a new test for a dhthell scenario that was failing

bitswap.go

@@ -128,7 +128,7 @@ func (bs *bitswap) sendWantListTo(ctx context.Context, peers <-chan peer.Peer) e
 			log.Event(ctx, "DialPeer", p)
 			err := bs.sender.DialPeer(ctx, p)
 			if err != nil {
-				log.Errorf("Error sender.DialPeer(%s)", p)
+				log.Errorf("Error sender.DialPeer(%s): %s", p, err)
 				return
 			}
 
@@ -153,10 +153,8 @@ func (bs *bitswap) sendWantListTo(ctx context.Context, peers <-chan peer.Peer) e
 
 func (bs *bitswap) run(ctx context.Context) {
 
-	const batchDelay = time.Millisecond * 3 // Time to wait before sending out wantlists to better batch up requests
-	const numKeysPerBatch = 10
-	const maxProvidersPerRequest = 6
-	const rebroadcastPeriod = time.Second * 5 // Every so often, we should resend out our current want list
+	// Every so often, we should resend out our current want list
+	rebroadcastTime := time.Second * 5
 
 	var providers <-chan peer.Peer // NB: must be initialized to zero value
 	broadcastSignal := time.After(rebroadcastPeriod)

bitswap_test.go

@@ -100,7 +100,7 @@ func TestSwarm(t *testing.T) {
 
 	t.Log("Create a ton of instances, and just a few blocks")
 
-	numInstances := 5
+	numInstances := 500
 	numBlocks := 2
 
 	instances := sg.Instances(numInstances)
@@ -140,6 +140,57 @@ func TestSwarm(t *testing.T) {
 	}
 }
 
+func TestLargeFile(t *testing.T) {
+	if testing.Short() {
+		t.SkipNow()
+	}
+	net := tn.VirtualNetwork()
+	rs := mock.VirtualRoutingServer()
+	sg := NewSessionGenerator(net, rs)
+	bg := NewBlockGenerator()
+
+	t.Log("Test a few nodes trying to get one file with a lot of blocks")
+
+	numInstances := 10
+	numBlocks := 100
+
+	instances := sg.Instances(numInstances)
+	blocks := bg.Blocks(numBlocks)
+
+	t.Log("Give the blocks to the first instance")
+
+	first := instances[0]
+	for _, b := range blocks {
+		first.blockstore.Put(b)
+		first.exchange.HasBlock(context.Background(), *b)
+		rs.Announce(first.peer, b.Key())
+	}
+
+	t.Log("Distribute!")
+
+	var wg sync.WaitGroup
+
+	for _, inst := range instances {
+		for _, b := range blocks {
+			wg.Add(1)
+			// NB: executing getOrFail concurrently puts tremendous pressure on
+			// the goroutine scheduler
+			getOrFail(inst, b, t, &wg)
+		}
+	}
+	wg.Wait()
+
+	t.Log("Verify!")
+
+	for _, inst := range instances {
+		for _, b := range blocks {
+			if _, err := inst.blockstore.Get(b.Key()); err != nil {
+				t.Fatal(err)
+			}
+		}
+	}
+}
+
 func getOrFail(bitswap instance, b *blocks.Block, t *testing.T, wg *sync.WaitGroup) {
 	if _, err := bitswap.blockstore.Get(b.Key()); err != nil {
 		_, err := bitswap.exchange.GetBlock(context.Background(), b.Key())