diff --git a/eth/downloader/downloader.go b/eth/downloader/downloader.go
index 0bc8b4acf1440f8823099e77f4abcfd75a612a9e..92124cfeb2dfb663b51cc50395a1cdf693b72787 100644
--- a/eth/downloader/downloader.go
+++ b/eth/downloader/downloader.go
@@ -54,14 +54,15 @@ var (
blockTargetRTT = 3 * time.Second / 2 // [eth/61] Target time for completing a block retrieval request
blockTTL = 3 * blockTargetRTT // [eth/61] Maximum time allowance before a block request is considered expired
- headerTargetRTT = time.Second // [eth/62] Target time for completing a header retrieval request (only for measurements for now)
- headerTTL = 3 * time.Second // [eth/62] Time it takes for a header request to time out
- bodyTargetRTT = 3 * time.Second / 2 // [eth/62] Target time for completing a block body retrieval request
- bodyTTL = 3 * bodyTargetRTT // [eth/62] Maximum time allowance before a block body request is considered expired
- receiptTargetRTT = 3 * time.Second / 2 // [eth/63] Target time for completing a receipt retrieval request
- receiptTTL = 3 * receiptTargetRTT // [eth/63] Maximum time allowance before a receipt request is considered expired
- stateTargetRTT = 2 * time.Second / 2 // [eth/63] Target time for completing a state trie retrieval request
- stateTTL = 3 * stateTargetRTT // [eth/63] Maximum time allowance before a node data request is considered expired
+ rttMinEstimate = 2 * time.Second // Minimum round-trip time to target for download requests
+ rttMaxEstimate = 20 * time.Second // Maximum rount-trip time to target for download requests
+ rttMinConfidence = 0.1 // Worse confidence factor in our estimated RTT value
+ ttlScaling = 3 // Constant scaling factor for RTT -> TTL conversion
+ ttlLimit = time.Minute // Maximum TTL allowance to prevent reaching crazy timeouts
+
+ qosTuningPeers = 5 // Number of peers to tune based on (best peers)
+ qosConfidenceCap = 10 // Number of peers above which not to modify RTT confidence
+ qosTuningImpact = 0.25 // Impact that a new tuning target has on the previous value
maxQueuedHashes = 32 * 1024 // [eth/61] Maximum number of hashes to queue for import (DOS protection)
maxQueuedHeaders = 32 * 1024 // [eth/62] Maximum number of headers to queue for import (DOS protection)
@@ -113,7 +114,8 @@ type Downloader struct {
fsPivotLock *types.Header // Pivot header on critical section entry (cannot change between retries)
fsPivotFails int // Number of fast sync failures in the critical section
- interrupt int32 // Atomic boolean to signal termination
+ rttEstimate uint64 // Round trip time to target for download requests
+ rttConfidence uint64 // Confidence in the estimated RTT (unit: millionths to allow atomic ops)
// Statistics
syncStatsChainOrigin uint64 // Origin block number where syncing started at
@@ -159,6 +161,9 @@ type Downloader struct {
cancelCh chan struct{} // Channel to cancel mid-flight syncs
cancelLock sync.RWMutex // Lock to protect the cancel channel in delivers
+ quitCh chan struct{} // Quit channel to signal termination
+ quitLock sync.RWMutex // Lock to prevent double closes
+
// Testing hooks
syncInitHook func(uint64, uint64) // Method to call upon initiating a new sync run
bodyFetchHook func([]*types.Header) // Method to call upon starting a block body fetch
@@ -172,11 +177,13 @@ func New(stateDb ethdb.Database, mux *event.TypeMux, hasHeader headerCheckFn, ha
headFastBlock headFastBlockRetrievalFn, commitHeadBlock headBlockCommitterFn, getTd tdRetrievalFn, insertHeaders headerChainInsertFn,
insertBlocks blockChainInsertFn, insertReceipts receiptChainInsertFn, rollback chainRollbackFn, dropPeer peerDropFn) *Downloader {
- return &Downloader{
+ dl := &Downloader{
mode: FullSync,
mux: mux,
queue: newQueue(stateDb),
peers: newPeerSet(),
+ rttEstimate: uint64(rttMaxEstimate),
+ rttConfidence: uint64(1000000),
hasHeader: hasHeader,
hasBlockAndState: hasBlockAndState,
getHeader: getHeader,
@@ -203,7 +210,10 @@ func New(stateDb ethdb.Database, mux *event.TypeMux, hasHeader headerCheckFn, ha
receiptWakeCh: make(chan bool, 1),
stateWakeCh: make(chan bool, 1),
headerProcCh: make(chan []*types.Header, 1),
+ quitCh: make(chan struct{}),
}
+ go dl.qosTuner()
+ return dl
}
// Progress retrieves the synchronisation boundaries, specifically the origin
@@ -250,6 +260,8 @@ func (d *Downloader) RegisterPeer(id string, version int, head common.Hash,
glog.V(logger.Error).Infoln("Register failed:", err)
return err
}
+ d.qosReduceConfidence()
+
return nil
}
@@ -515,7 +527,16 @@ func (d *Downloader) cancel() {
// Terminate interrupts the downloader, canceling all pending operations.
// The downloader cannot be reused after calling Terminate.
func (d *Downloader) Terminate() {
- atomic.StoreInt32(&d.interrupt, 1)
+ // Close the termination channel (make sure double close is allowed)
+ d.quitLock.Lock()
+ select {
+ case <-d.quitCh:
+ default:
+ close(d.quitCh)
+ }
+ d.quitLock.Unlock()
+
+ // Cancel any pending download requests
d.cancel()
}
@@ -932,7 +953,7 @@ func (d *Downloader) fetchBlocks61(from uint64) error {
// Reserve a chunk of hashes for a peer. A nil can mean either that
// no more hashes are available, or that the peer is known not to
// have them.
- request := d.queue.ReserveBlocks(peer, peer.BlockCapacity())
+ request := d.queue.ReserveBlocks(peer, peer.BlockCapacity(blockTargetRTT))
if request == nil {
continue
}
@@ -973,7 +994,7 @@ func (d *Downloader) fetchHeight(p *peer) (*types.Header, error) {
// Request the advertised remote head block and wait for the response
go p.getRelHeaders(p.head, 1, 0, false)
- timeout := time.After(headerTTL)
+ timeout := time.After(d.requestTTL())
for {
select {
case <-d.cancelCh:
@@ -1041,7 +1062,7 @@ func (d *Downloader) findAncestor(p *peer, height uint64) (uint64, error) {
// Wait for the remote response to the head fetch
number, hash := uint64(0), common.Hash{}
- timeout := time.After(hashTTL)
+ timeout := time.After(d.requestTTL())
for finished := false; !finished; {
select {
@@ -1118,7 +1139,7 @@ func (d *Downloader) findAncestor(p *peer, height uint64) (uint64, error) {
// Split our chain interval in two, and request the hash to cross check
check := (start + end) / 2
- timeout := time.After(hashTTL)
+ timeout := time.After(d.requestTTL())
go p.getAbsHeaders(uint64(check), 1, 0, false)
// Wait until a reply arrives to this request
@@ -1199,7 +1220,7 @@ func (d *Downloader) fetchHeaders(p *peer, from uint64) error {
getHeaders := func(from uint64) {
request = time.Now()
- timeout.Reset(headerTTL)
+ timeout.Reset(d.requestTTL())
if skeleton {
glog.V(logger.Detail).Infof("%v: fetching %d skeleton headers from #%d", p, MaxHeaderFetch, from)
@@ -1311,13 +1332,13 @@ func (d *Downloader) fillHeaderSkeleton(from uint64, skeleton []*types.Header) (
pack := packet.(*headerPack)
return d.queue.DeliverHeaders(pack.peerId, pack.headers, d.headerProcCh)
}
- expire = func() map[string]int { return d.queue.ExpireHeaders(headerTTL) }
+ expire = func() map[string]int { return d.queue.ExpireHeaders(d.requestTTL()) }
throttle = func() bool { return false }
reserve = func(p *peer, count int) (*fetchRequest, bool, error) {
return d.queue.ReserveHeaders(p, count), false, nil
}
fetch = func(p *peer, req *fetchRequest) error { return p.FetchHeaders(req.From, MaxHeaderFetch) }
- capacity = func(p *peer) int { return p.HeaderCapacity() }
+ capacity = func(p *peer) int { return p.HeaderCapacity(d.requestRTT()) }
setIdle = func(p *peer, accepted int) { p.SetHeadersIdle(accepted) }
)
err := d.fetchParts(errCancelHeaderFetch, d.headerCh, deliver, d.queue.headerContCh, expire,
@@ -1341,9 +1362,9 @@ func (d *Downloader) fetchBodies(from uint64) error {
pack := packet.(*bodyPack)
return d.queue.DeliverBodies(pack.peerId, pack.transactions, pack.uncles)
}
- expire = func() map[string]int { return d.queue.ExpireBodies(bodyTTL) }
+ expire = func() map[string]int { return d.queue.ExpireBodies(d.requestTTL()) }
fetch = func(p *peer, req *fetchRequest) error { return p.FetchBodies(req) }
- capacity = func(p *peer) int { return p.BlockCapacity() }
+ capacity = func(p *peer) int { return p.BlockCapacity(d.requestRTT()) }
setIdle = func(p *peer, accepted int) { p.SetBodiesIdle(accepted) }
)
err := d.fetchParts(errCancelBodyFetch, d.bodyCh, deliver, d.bodyWakeCh, expire,
@@ -1365,9 +1386,9 @@ func (d *Downloader) fetchReceipts(from uint64) error {
pack := packet.(*receiptPack)
return d.queue.DeliverReceipts(pack.peerId, pack.receipts)
}
- expire = func() map[string]int { return d.queue.ExpireReceipts(receiptTTL) }
+ expire = func() map[string]int { return d.queue.ExpireReceipts(d.requestTTL()) }
fetch = func(p *peer, req *fetchRequest) error { return p.FetchReceipts(req) }
- capacity = func(p *peer) int { return p.ReceiptCapacity() }
+ capacity = func(p *peer) int { return p.ReceiptCapacity(d.requestRTT()) }
setIdle = func(p *peer, accepted int) { p.SetReceiptsIdle(accepted) }
)
err := d.fetchParts(errCancelReceiptFetch, d.receiptCh, deliver, d.receiptWakeCh, expire,
@@ -1417,13 +1438,13 @@ func (d *Downloader) fetchNodeData() error {
}
})
}
- expire = func() map[string]int { return d.queue.ExpireNodeData(stateTTL) }
+ expire = func() map[string]int { return d.queue.ExpireNodeData(d.requestTTL()) }
throttle = func() bool { return false }
reserve = func(p *peer, count int) (*fetchRequest, bool, error) {
return d.queue.ReserveNodeData(p, count), false, nil
}
fetch = func(p *peer, req *fetchRequest) error { return p.FetchNodeData(req) }
- capacity = func(p *peer) int { return p.NodeDataCapacity() }
+ capacity = func(p *peer) int { return p.NodeDataCapacity(d.requestRTT()) }
setIdle = func(p *peer, accepted int) { p.SetNodeDataIdle(accepted) }
)
err := d.fetchParts(errCancelStateFetch, d.stateCh, deliver, d.stateWakeCh, expire,
@@ -1799,8 +1820,10 @@ func (d *Downloader) processContent() error {
}
for len(results) != 0 {
// Check for any termination requests
- if atomic.LoadInt32(&d.interrupt) == 1 {
+ select {
+ case <-d.quitCh:
return errCancelContentProcessing
+ default:
}
// Retrieve the a batch of results to import
var (
@@ -1901,3 +1924,74 @@ func (d *Downloader) deliver(id string, destCh chan dataPack, packet dataPack, i
return errNoSyncActive
}
}
+
+// qosTuner is the quality of service tuning loop that occasionally gathers the
+// peer latency statistics and updates the estimated request round trip time.
+func (d *Downloader) qosTuner() {
+ for {
+ // Retrieve the current median RTT and integrate into the previoust target RTT
+ rtt := time.Duration(float64(1-qosTuningImpact)*float64(atomic.LoadUint64(&d.rttEstimate)) + qosTuningImpact*float64(d.peers.medianRTT()))
+ atomic.StoreUint64(&d.rttEstimate, uint64(rtt))
+
+ // A new RTT cycle passed, increase our confidence in the estimated RTT
+ conf := atomic.LoadUint64(&d.rttConfidence)
+ conf = conf + (1000000-conf)/2
+ atomic.StoreUint64(&d.rttConfidence, conf)
+
+ // Log the new QoS values and sleep until the next RTT
+ glog.V(logger.Debug).Infof("Quality of service: rtt %v, conf %.3f, ttl %v", rtt, float64(conf)/1000000.0, d.requestTTL())
+ select {
+ case <-d.quitCh:
+ return
+ case <-time.After(rtt):
+ }
+ }
+}
+
+// qosReduceConfidence is meant to be called when a new peer joins the downloader's
+// peer set, needing to reduce the confidence we have in out QoS estimates.
+func (d *Downloader) qosReduceConfidence() {
+ // If we have a single peer, confidence is always 1
+ peers := uint64(d.peers.Len())
+ if peers == 1 {
+ atomic.StoreUint64(&d.rttConfidence, 1000000)
+ return
+ }
+ // If we have a ton of peers, don't drop confidence)
+ if peers >= uint64(qosConfidenceCap) {
+ return
+ }
+ // Otherwise drop the confidence factor
+ conf := atomic.LoadUint64(&d.rttConfidence) * (peers - 1) / peers
+ if float64(conf)/1000000 < rttMinConfidence {
+ conf = uint64(rttMinConfidence * 1000000)
+ }
+ atomic.StoreUint64(&d.rttConfidence, conf)
+
+ rtt := time.Duration(atomic.LoadUint64(&d.rttEstimate))
+ glog.V(logger.Debug).Infof("Quality of service: rtt %v, conf %.3f, ttl %v", rtt, float64(conf)/1000000.0, d.requestTTL())
+}
+
+// requestRTT returns the current target round trip time for a download request
+// to complete in.
+//
+// Note, the returned RTT is .9 of the actually estimated RTT. The reason is that
+// the downloader tries to adapt queries to the RTT, so multiple RTT values can
+// be adapted to, but smaller ones are preffered (stabler download stream).
+func (d *Downloader) requestRTT() time.Duration {
+ return time.Duration(atomic.LoadUint64(&d.rttEstimate)) * 9 / 10
+}
+
+// requestTTL returns the current timeout allowance for a single download request
+// to finish under.
+func (d *Downloader) requestTTL() time.Duration {
+ var (
+ rtt = time.Duration(atomic.LoadUint64(&d.rttEstimate))
+ conf = float64(atomic.LoadUint64(&d.rttConfidence)) / 1000000.0
+ )
+ ttl := time.Duration(ttlScaling) * time.Duration(float64(rtt)/conf)
+ if ttl > ttlLimit {
+ ttl = ttlLimit
+ }
+ return ttl
+}
diff --git a/eth/downloader/downloader_test.go b/eth/downloader/downloader_test.go
index f3a0e38f1ae506ef88220d29ad8d9b58c2e6122e..a9c069a926bc672e2b5185026d53d9523f5b9ca3 100644
--- a/eth/downloader/downloader_test.go
+++ b/eth/downloader/downloader_test.go
@@ -179,6 +179,12 @@ func newTester() *downloadTester {
return tester
}
+// terminate aborts any operations on the embedded downloader and releases all
+// held resources.
+func (dl *downloadTester) terminate() {
+ dl.downloader.Terminate()
+}
+
// sync starts synchronizing with a remote peer, blocking until it completes.
func (dl *downloadTester) sync(id string, td *big.Int, mode SyncMode) error {
dl.lock.RLock()
@@ -740,6 +746,8 @@ func testCanonicalSynchronisation(t *testing.T, protocol int, mode SyncMode) {
hashes, headers, blocks, receipts := makeChain(targetBlocks, 0, genesis, nil, false)
tester := newTester()
+ defer tester.terminate()
+
tester.newPeer("peer", protocol, hashes, headers, blocks, receipts)
// Synchronise with the peer and make sure all relevant data was retrieved
@@ -764,6 +772,8 @@ func testThrottling(t *testing.T, protocol int, mode SyncMode) {
hashes, headers, blocks, receipts := makeChain(targetBlocks, 0, genesis, nil, false)
tester := newTester()
+ defer tester.terminate()
+
tester.newPeer("peer", protocol, hashes, headers, blocks, receipts)
// Wrap the importer to allow stepping
@@ -851,6 +861,8 @@ func testForkedSync(t *testing.T, protocol int, mode SyncMode) {
hashesA, hashesB, headersA, headersB, blocksA, blocksB, receiptsA, receiptsB := makeChainFork(common+fork, fork, genesis, nil, true)
tester := newTester()
+ defer tester.terminate()
+
tester.newPeer("fork A", protocol, hashesA, headersA, blocksA, receiptsA)
tester.newPeer("fork B", protocol, hashesB, headersB, blocksB, receiptsB)
@@ -885,6 +897,8 @@ func testHeavyForkedSync(t *testing.T, protocol int, mode SyncMode) {
hashesA, hashesB, headersA, headersB, blocksA, blocksB, receiptsA, receiptsB := makeChainFork(common+fork, fork, genesis, nil, false)
tester := newTester()
+ defer tester.terminate()
+
tester.newPeer("light", protocol, hashesA, headersA, blocksA, receiptsA)
tester.newPeer("heavy", protocol, hashesB[fork/2:], headersB, blocksB, receiptsB)
@@ -934,6 +948,8 @@ func testBoundedForkedSync(t *testing.T, protocol int, mode SyncMode) {
hashesA, hashesB, headersA, headersB, blocksA, blocksB, receiptsA, receiptsB := makeChainFork(common+fork, fork, genesis, nil, true)
tester := newTester()
+ defer tester.terminate()
+
tester.newPeer("original", protocol, hashesA, headersA, blocksA, receiptsA)
tester.newPeer("rewriter", protocol, hashesB, headersB, blocksB, receiptsB)
@@ -968,6 +984,8 @@ func testBoundedHeavyForkedSync(t *testing.T, protocol int, mode SyncMode) {
hashesA, hashesB, headersA, headersB, blocksA, blocksB, receiptsA, receiptsB := makeChainFork(common+fork, fork, genesis, nil, false)
tester := newTester()
+ defer tester.terminate()
+
tester.newPeer("original", protocol, hashesA, headersA, blocksA, receiptsA)
tester.newPeer("heavy-rewriter", protocol, hashesB[MaxForkAncestry-17:], headersB, blocksB, receiptsB) // Root the fork below the ancestor limit
@@ -987,7 +1005,9 @@ func testBoundedHeavyForkedSync(t *testing.T, protocol int, mode SyncMode) {
// bodies.
func TestInactiveDownloader62(t *testing.T) {
t.Parallel()
+
tester := newTester()
+ defer tester.terminate()
// Check that neither block headers nor bodies are accepted
if err := tester.downloader.DeliverHeaders("bad peer", []*types.Header{}); err != errNoSyncActive {
@@ -1002,7 +1022,9 @@ func TestInactiveDownloader62(t *testing.T) {
// bodies and receipts.
func TestInactiveDownloader63(t *testing.T) {
t.Parallel()
+
tester := newTester()
+ defer tester.terminate()
// Check that neither block headers nor bodies are accepted
if err := tester.downloader.DeliverHeaders("bad peer", []*types.Header{}); err != errNoSyncActive {
@@ -1039,6 +1061,8 @@ func testCancel(t *testing.T, protocol int, mode SyncMode) {
hashes, headers, blocks, receipts := makeChain(targetBlocks, 0, genesis, nil, false)
tester := newTester()
+ defer tester.terminate()
+
tester.newPeer("peer", protocol, hashes, headers, blocks, receipts)
// Make sure canceling works with a pristine downloader
@@ -1074,6 +1098,8 @@ func testMultiSynchronisation(t *testing.T, protocol int, mode SyncMode) {
hashes, headers, blocks, receipts := makeChain(targetBlocks, 0, genesis, nil, false)
tester := newTester()
+ defer tester.terminate()
+
for i := 0; i < targetPeers; i++ {
id := fmt.Sprintf("peer #%d", i)
tester.newPeer(id, protocol, hashes[i*blockCacheLimit:], headers, blocks, receipts)
@@ -1103,6 +1129,8 @@ func testMultiProtoSync(t *testing.T, protocol int, mode SyncMode) {
// Create peers of every type
tester := newTester()
+ defer tester.terminate()
+
tester.newPeer("peer 61", 61, hashes, nil, blocks, nil)
tester.newPeer("peer 62", 62, hashes, headers, blocks, nil)
tester.newPeer("peer 63", 63, hashes, headers, blocks, receipts)
@@ -1140,6 +1168,8 @@ func testEmptyShortCircuit(t *testing.T, protocol int, mode SyncMode) {
hashes, headers, blocks, receipts := makeChain(targetBlocks, 0, genesis, nil, false)
tester := newTester()
+ defer tester.terminate()
+
tester.newPeer("peer", protocol, hashes, headers, blocks, receipts)
// Instrument the downloader to signal body requests
@@ -1193,6 +1223,7 @@ func testMissingHeaderAttack(t *testing.T, protocol int, mode SyncMode) {
hashes, headers, blocks, receipts := makeChain(targetBlocks, 0, genesis, nil, false)
tester := newTester()
+ defer tester.terminate()
// Attempt a full sync with an attacker feeding gapped headers
tester.newPeer("attack", protocol, hashes, headers, blocks, receipts)
@@ -1225,6 +1256,7 @@ func testShiftedHeaderAttack(t *testing.T, protocol int, mode SyncMode) {
hashes, headers, blocks, receipts := makeChain(targetBlocks, 0, genesis, nil, false)
tester := newTester()
+ defer tester.terminate()
// Attempt a full sync with an attacker feeding shifted headers
tester.newPeer("attack", protocol, hashes, headers, blocks, receipts)
@@ -1256,6 +1288,7 @@ func testInvalidHeaderRollback(t *testing.T, protocol int, mode SyncMode) {
hashes, headers, blocks, receipts := makeChain(targetBlocks, 0, genesis, nil, false)
tester := newTester()
+ defer tester.terminate()
// Attempt to sync with an attacker that feeds junk during the fast sync phase.
// This should result in the last fsHeaderSafetyNet headers being rolled back.
@@ -1347,9 +1380,11 @@ func testHighTDStarvationAttack(t *testing.T, protocol int, mode SyncMode) {
t.Parallel()
tester := newTester()
- hashes, headers, blocks, receipts := makeChain(0, 0, genesis, nil, false)
+ defer tester.terminate()
+ hashes, headers, blocks, receipts := makeChain(0, 0, genesis, nil, false)
tester.newPeer("attack", protocol, []common.Hash{hashes[0]}, headers, blocks, receipts)
+
if err := tester.sync("attack", big.NewInt(1000000), mode); err != errStallingPeer {
t.Fatalf("synchronisation error mismatch: have %v, want %v", err, errStallingPeer)
}
@@ -1392,6 +1427,8 @@ func testBlockHeaderAttackerDropping(t *testing.T, protocol int) {
}
// Run the tests and check disconnection status
tester := newTester()
+ defer tester.terminate()
+
for i, tt := range tests {
// Register a new peer and ensure it's presence
id := fmt.Sprintf("test %d", i)
@@ -1433,6 +1470,8 @@ func testSyncProgress(t *testing.T, protocol int, mode SyncMode) {
progress := make(chan struct{})
tester := newTester()
+ defer tester.terminate()
+
tester.downloader.syncInitHook = func(origin, latest uint64) {
starting <- struct{}{}
<-progress
@@ -1505,6 +1544,8 @@ func testForkedSyncProgress(t *testing.T, protocol int, mode SyncMode) {
progress := make(chan struct{})
tester := newTester()
+ defer tester.terminate()
+
tester.downloader.syncInitHook = func(origin, latest uint64) {
starting <- struct{}{}
<-progress
@@ -1580,6 +1621,8 @@ func testFailedSyncProgress(t *testing.T, protocol int, mode SyncMode) {
progress := make(chan struct{})
tester := newTester()
+ defer tester.terminate()
+
tester.downloader.syncInitHook = func(origin, latest uint64) {
starting <- struct{}{}
<-progress
@@ -1656,6 +1699,8 @@ func testFakedSyncProgress(t *testing.T, protocol int, mode SyncMode) {
progress := make(chan struct{})
tester := newTester()
+ defer tester.terminate()
+
tester.downloader.syncInitHook = func(origin, latest uint64) {
starting <- struct{}{}
<-progress
@@ -1742,7 +1787,7 @@ func testDeliverHeadersHang(t *testing.T, protocol int, mode SyncMode) {
impl := tester.peerGetAbsHeadersFn("peer", 0)
go impl(from, count, skip, reverse)
// None of the extra deliveries should block.
- timeout := time.After(5 * time.Second)
+ timeout := time.After(15 * time.Second)
for i := 0; i < cap(deliveriesDone); i++ {
select {
case <-deliveriesDone:
@@ -1755,6 +1800,7 @@ func testDeliverHeadersHang(t *testing.T, protocol int, mode SyncMode) {
if err := tester.sync("peer", nil, mode); err != nil {
t.Errorf("sync failed: %v", err)
}
+ tester.terminate()
}
}
@@ -1772,8 +1818,9 @@ func testFastCriticalRestarts(t *testing.T, protocol int) {
// Create a tester peer with the critical section state roots missing (force failures)
tester := newTester()
- tester.newPeer("peer", protocol, hashes, headers, blocks, receipts)
+ defer tester.terminate()
+ tester.newPeer("peer", protocol, hashes, headers, blocks, receipts)
for i := 0; i < fsPivotInterval; i++ {
tester.peerMissingStates["peer"][headers[hashes[fsMinFullBlocks+i]].Root] = true
}
@@ -1783,11 +1830,14 @@ func testFastCriticalRestarts(t *testing.T, protocol int) {
if err := tester.sync("peer", nil, FastSync); err == nil {
t.Fatalf("failing fast sync succeeded: %v", err)
}
+ time.Sleep(500 * time.Millisecond) // Make sure no in-flight requests remain
+
// If it's the first failure, pivot should be locked => reenable all others to detect pivot changes
if i == 0 {
+ tester.lock.Lock()
tester.peerMissingStates["peer"] = map[common.Hash]bool{tester.downloader.fsPivotLock.Root: true}
+ tester.lock.Unlock()
}
- time.Sleep(100 * time.Millisecond) // Make sure no in-flight requests remain
}
// Retry limit exhausted, downloader will switch to full sync, should succeed
if err := tester.sync("peer", nil, FastSync); err != nil {
diff --git a/eth/downloader/peer.go b/eth/downloader/peer.go
index 6aab907d7e1351034449b4eccb1e3fe6bf401aa9..94d44fca46502df9f52840438f2a5bedd377d1d5 100644
--- a/eth/downloader/peer.go
+++ b/eth/downloader/peer.go
@@ -23,6 +23,8 @@ import (
"errors"
"fmt"
"math"
+ "sort"
+ "strings"
"sync"
"sync/atomic"
"time"
@@ -31,8 +33,8 @@ import (
)
const (
- maxLackingHashes = 4096 // Maximum number of entries allowed on the list or lacking items
- throughputImpact = 0.1 // The impact a single measurement has on a peer's final throughput value.
+ maxLackingHashes = 4096 // Maximum number of entries allowed on the list or lacking items
+ measurementImpact = 0.1 // The impact a single measurement has on a peer's final throughput value.
)
// Hash and block fetchers belonging to eth/61 and below
@@ -68,6 +70,8 @@ type peer struct {
receiptThroughput float64 // Number of receipts measured to be retrievable per second
stateThroughput float64 // Number of node data pieces measured to be retrievable per second
+ rtt time.Duration // Request round trip time to track responsiveness (QoS)
+
headerStarted time.Time // Time instance when the last header fetch was started
blockStarted time.Time // Time instance when the last block (body) fetch was started
receiptStarted time.Time // Time instance when the last receipt fetch was started
@@ -290,44 +294,47 @@ func (p *peer) setIdle(started time.Time, delivered int, throughput *float64, id
return
}
// Otherwise update the throughput with a new measurement
- measured := float64(delivered) / (float64(time.Since(started)+1) / float64(time.Second)) // +1 (ns) to ensure non-zero divisor
- *throughput = (1-throughputImpact)*(*throughput) + throughputImpact*measured
+ elapsed := time.Since(started) + 1 // +1 (ns) to ensure non-zero divisor
+ measured := float64(delivered) / (float64(elapsed) / float64(time.Second))
+
+ *throughput = (1-measurementImpact)*(*throughput) + measurementImpact*measured
+ p.rtt = time.Duration((1-measurementImpact)*float64(p.rtt) + measurementImpact*float64(elapsed))
}
// HeaderCapacity retrieves the peers header download allowance based on its
// previously discovered throughput.
-func (p *peer) HeaderCapacity() int {
+func (p *peer) HeaderCapacity(targetRTT time.Duration) int {
p.lock.RLock()
defer p.lock.RUnlock()
- return int(math.Max(1, math.Min(p.headerThroughput*float64(headerTargetRTT)/float64(time.Second), float64(MaxHeaderFetch))))
+ return int(math.Min(1+math.Max(1, p.headerThroughput*float64(targetRTT)/float64(time.Second)), float64(MaxHeaderFetch)))
}
// BlockCapacity retrieves the peers block download allowance based on its
// previously discovered throughput.
-func (p *peer) BlockCapacity() int {
+func (p *peer) BlockCapacity(targetRTT time.Duration) int {
p.lock.RLock()
defer p.lock.RUnlock()
- return int(math.Max(1, math.Min(p.blockThroughput*float64(blockTargetRTT)/float64(time.Second), float64(MaxBlockFetch))))
+ return int(math.Min(1+math.Max(1, p.blockThroughput*float64(targetRTT)/float64(time.Second)), float64(MaxBlockFetch)))
}
// ReceiptCapacity retrieves the peers receipt download allowance based on its
// previously discovered throughput.
-func (p *peer) ReceiptCapacity() int {
+func (p *peer) ReceiptCapacity(targetRTT time.Duration) int {
p.lock.RLock()
defer p.lock.RUnlock()
- return int(math.Max(1, math.Min(p.receiptThroughput*float64(receiptTargetRTT)/float64(time.Second), float64(MaxReceiptFetch))))
+ return int(math.Min(1+math.Max(1, p.receiptThroughput*float64(targetRTT)/float64(time.Second)), float64(MaxReceiptFetch)))
}
// NodeDataCapacity retrieves the peers state download allowance based on its
// previously discovered throughput.
-func (p *peer) NodeDataCapacity() int {
+func (p *peer) NodeDataCapacity(targetRTT time.Duration) int {
p.lock.RLock()
defer p.lock.RUnlock()
- return int(math.Max(1, math.Min(p.stateThroughput*float64(stateTargetRTT)/float64(time.Second), float64(MaxStateFetch))))
+ return int(math.Min(1+math.Max(1, p.stateThroughput*float64(targetRTT)/float64(time.Second)), float64(MaxStateFetch)))
}
// MarkLacking appends a new entity to the set of items (blocks, receipts, states)
@@ -361,13 +368,14 @@ func (p *peer) String() string {
p.lock.RLock()
defer p.lock.RUnlock()
- return fmt.Sprintf("Peer %s [%s]", p.id,
- fmt.Sprintf("headers %3.2f/s, ", p.headerThroughput)+
- fmt.Sprintf("blocks %3.2f/s, ", p.blockThroughput)+
- fmt.Sprintf("receipts %3.2f/s, ", p.receiptThroughput)+
- fmt.Sprintf("states %3.2f/s, ", p.stateThroughput)+
- fmt.Sprintf("lacking %4d", len(p.lacking)),
- )
+ return fmt.Sprintf("Peer %s [%s]", p.id, strings.Join([]string{
+ fmt.Sprintf("hs %3.2f/s", p.headerThroughput),
+ fmt.Sprintf("bs %3.2f/s", p.blockThroughput),
+ fmt.Sprintf("rs %3.2f/s", p.receiptThroughput),
+ fmt.Sprintf("ss %3.2f/s", p.stateThroughput),
+ fmt.Sprintf("miss %4d", len(p.lacking)),
+ fmt.Sprintf("rtt %v", p.rtt),
+ }, ", "))
}
// peerSet represents the collection of active peer participating in the chain
@@ -402,6 +410,10 @@ func (ps *peerSet) Reset() {
// average of all existing peers, to give it a realistic chance of being used
// for data retrievals.
func (ps *peerSet) Register(p *peer) error {
+ // Retrieve the current median RTT as a sane default
+ p.rtt = ps.medianRTT()
+
+ // Register the new peer with some meaningful defaults
ps.lock.Lock()
defer ps.lock.Unlock()
@@ -564,3 +576,34 @@ func (ps *peerSet) idlePeers(minProtocol, maxProtocol int, idleCheck func(*peer)
}
return idle, total
}
+
+// medianRTT returns the median RTT of te peerset, considering only the tuning
+// peers if there are more peers available.
+func (ps *peerSet) medianRTT() time.Duration {
+ // Gather all the currnetly measured round trip times
+ ps.lock.RLock()
+ defer ps.lock.RUnlock()
+
+ rtts := make([]float64, 0, len(ps.peers))
+ for _, p := range ps.peers {
+ p.lock.RLock()
+ rtts = append(rtts, float64(p.rtt))
+ p.lock.RUnlock()
+ }
+ sort.Float64s(rtts)
+
+ median := rttMaxEstimate
+ if qosTuningPeers <= len(rtts) {
+ median = time.Duration(rtts[qosTuningPeers/2]) // Median of our tuning peers
+ } else if len(rtts) > 0 {
+ median = time.Duration(rtts[len(rtts)/2]) // Median of our connected peers (maintain even like this some baseline qos)
+ }
+ // Restrict the RTT into some QoS defaults, irrelevant of true RTT
+ if median < rttMinEstimate {
+ median = rttMinEstimate
+ }
+ if median > rttMaxEstimate {
+ median = rttMaxEstimate
+ }
+ return median
+}