This commit is contained in:
Péter Szilágyi 2016-06-03 12:24:56 +00:00
commit fe263175f7
6 changed files with 289 additions and 72 deletions

View file

@ -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)
@ -73,6 +74,7 @@ var (
fsHeaderForceVerify = 24 // Number of headers to verify before and after the pivot to accept it
fsPivotInterval = 512 // Number of headers out of which to randomize the pivot point
fsMinFullBlocks = 1024 // Number of blocks to retrieve fully even in fast sync
fsCriticalTrials = 10 // Number of times to retry in the cricical section before bailing
)
var (
@ -103,13 +105,18 @@ var (
)
type Downloader struct {
mode SyncMode // Synchronisation mode defining the strategy used (per sync cycle)
noFast bool // Flag to disable fast syncing in case of a security error
mux *event.TypeMux // Event multiplexer to announce sync operation events
mode SyncMode // Synchronisation mode defining the strategy used (per sync cycle)
mux *event.TypeMux // Event multiplexer to announce sync operation events
queue *queue // Scheduler for selecting the hashes to download
peers *peerSet // Set of active peers from which download can proceed
fsPivotLock *types.Header // Pivot header on critical section entry (cannot change between retries)
fsPivotFails int // Number of fast sync failures in the critical section
rttEstimate uint64 // Round trip time to target for download requests
rttConfidence uint64 // Confidence in the estimated RTT (unit: millionths to allow atomic ops)
interrupt int32 // Atomic boolean to signal termination
// Statistics
@ -169,11 +176,13 @@ 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,
@ -201,6 +210,8 @@ func New(stateDb ethdb.Database, mux *event.TypeMux, hasHeader headerCheckFn, ha
stateWakeCh: make(chan bool, 1),
headerProcCh: make(chan []*types.Header, 1),
}
go dl.qosTuner()
return dl
}
// Progress retrieves the synchronisation boundaries, specifically the origin
@ -247,6 +258,8 @@ 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
}
@ -314,6 +327,15 @@ func (d *Downloader) synchronise(id string, hash common.Hash, td *big.Int, mode
default:
}
}
for _, ch := range []chan dataPack{d.hashCh, d.blockCh, d.headerCh, d.bodyCh, d.receiptCh, d.stateCh} {
for empty := false; !empty; {
select {
case <-ch:
default:
empty = true
}
}
}
for empty := false; !empty; {
select {
case <-d.headerProcCh:
@ -330,7 +352,7 @@ func (d *Downloader) synchronise(id string, hash common.Hash, td *big.Int, mode
// Set the requested sync mode, unless it's forbidden
d.mode = mode
if d.mode == FastSync && d.noFast {
if d.mode == FastSync && d.fsPivotFails >= fsCriticalTrials {
d.mode = FullSync
}
// Retrieve the origin peer and initiate the downloading process
@ -413,12 +435,17 @@ func (d *Downloader) syncWithPeer(p *peer, hash common.Hash, td *big.Int) (err e
pivot = height
case FastSync:
// Calculate the new fast/slow sync pivot point
pivotOffset, err := rand.Int(rand.Reader, big.NewInt(int64(fsPivotInterval)))
if err != nil {
panic(fmt.Sprintf("Failed to access crypto random source: %v", err))
}
if height > uint64(fsMinFullBlocks)+pivotOffset.Uint64() {
pivot = height - uint64(fsMinFullBlocks) - pivotOffset.Uint64()
if d.fsPivotLock == nil {
pivotOffset, err := rand.Int(rand.Reader, big.NewInt(int64(fsPivotInterval)))
if err != nil {
panic(fmt.Sprintf("Failed to access crypto random source: %v", err))
}
if height > uint64(fsMinFullBlocks)+pivotOffset.Uint64() {
pivot = height - uint64(fsMinFullBlocks) - pivotOffset.Uint64()
}
} else {
// Pivot point locked in, use this and do not pick a new one!
pivot = d.fsPivotLock.Number.Uint64()
}
// If the point is below the origin, move origin back to ensure state download
if pivot < origin {
@ -915,7 +942,7 @@ 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
}
@ -956,7 +983,7 @@ 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:
@ -1024,7 +1051,7 @@ 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 {
@ -1101,7 +1128,7 @@ 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
@ -1182,7 +1209,7 @@ 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)
@ -1218,8 +1245,12 @@ func (d *Downloader) fetchHeaders(p *peer, from uint64) error {
// If no more headers are inbound, notify the content fetchers and return
if packet.Items() == 0 {
glog.V(logger.Debug).Infof("%v: no available headers", p)
d.headerProcCh <- nil
return nil
select {
case d.headerProcCh <- nil:
return nil
case <-d.cancelCh:
return errCancelHeaderFetch
}
}
headers := packet.(*headerPack).headers
@ -1290,13 +1321,13 @@ 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,
@ -1320,9 +1351,9 @@ 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,
@ -1344,9 +1375,9 @@ 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,
@ -1396,13 +1427,13 @@ 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,
@ -1611,9 +1642,18 @@ func (d *Downloader) processHeaders(origin uint64, td *big.Int) error {
glog.V(logger.Warn).Infof("Rolled back %d headers (LH: %d->%d, FB: %d->%d, LB: %d->%d)",
len(hashes), lastHeader, d.headHeader().Number, lastFastBlock, d.headFastBlock().Number(), lastBlock, d.headBlock().Number())
// If we're already past the pivot point, this could be an attack, disable fast sync
// If we're already past the pivot point, this could be an attack, thread carefully
if rollback[len(rollback)-1].Number.Uint64() > pivot {
d.noFast = true
// If we didn't ever fail, lock in te pivot header (must! not! change!)
if d.fsPivotFails == 0 {
for _, header := range rollback {
if header.Number.Uint64() == pivot {
glog.V(logger.Warn).Infof("Fast-sync critical section failure, locked pivot to header #%d [%x…]", pivot, header.Hash().Bytes()[:4])
d.fsPivotLock = header
}
}
}
d.fsPivotFails++
}
}
}()
@ -1712,6 +1752,13 @@ func (d *Downloader) processHeaders(origin uint64, td *big.Int) error {
rollback = append(rollback[:0], rollback[len(rollback)-fsHeaderSafetyNet:]...)
}
}
// If we're fast syncing and just pulled in the pivot, make sure it's the one locked in
if d.mode == FastSync && d.fsPivotLock != nil && chunk[0].Number.Uint64() <= pivot && chunk[len(chunk)-1].Number.Uint64() >= pivot {
if pivot := chunk[int(pivot-chunk[0].Number.Uint64())]; pivot.Hash() != d.fsPivotLock.Hash() {
glog.V(logger.Warn).Infof("Pivot doesn't match locked in version: have #%v [%x…], want #%v [%x…]", pivot.Number, pivot.Hash().Bytes()[:4], d.fsPivotLock.Number, d.fsPivotLock.Hash().Bytes()[:4])
return errInvalidChain
}
}
// Unless we're doing light chains, schedule the headers for associated content retrieval
if d.mode == FullSync || d.mode == FastSync {
// If we've reached the allowed number of pending headers, stall a bit
@ -1864,3 +1911,70 @@ 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 atomic.LoadInt32(&d.interrupt) == 0 {
// 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())
time.Sleep(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
}

View file

@ -149,22 +149,25 @@ type downloadTester struct {
peerReceipts map[string]map[common.Hash]types.Receipts // Receipts belonging to different test peers
peerChainTds map[string]map[common.Hash]*big.Int // Total difficulties of the blocks in the peer chains
peerMissingStates map[string]map[common.Hash]bool // State entries that fast sync should not return
lock sync.RWMutex
}
// newTester creates a new downloader test mocker.
func newTester() *downloadTester {
tester := &downloadTester{
ownHashes: []common.Hash{genesis.Hash()},
ownHeaders: map[common.Hash]*types.Header{genesis.Hash(): genesis.Header()},
ownBlocks: map[common.Hash]*types.Block{genesis.Hash(): genesis},
ownReceipts: map[common.Hash]types.Receipts{genesis.Hash(): nil},
ownChainTd: map[common.Hash]*big.Int{genesis.Hash(): genesis.Difficulty()},
peerHashes: make(map[string][]common.Hash),
peerHeaders: make(map[string]map[common.Hash]*types.Header),
peerBlocks: make(map[string]map[common.Hash]*types.Block),
peerReceipts: make(map[string]map[common.Hash]types.Receipts),
peerChainTds: make(map[string]map[common.Hash]*big.Int),
ownHashes: []common.Hash{genesis.Hash()},
ownHeaders: map[common.Hash]*types.Header{genesis.Hash(): genesis.Header()},
ownBlocks: map[common.Hash]*types.Block{genesis.Hash(): genesis},
ownReceipts: map[common.Hash]types.Receipts{genesis.Hash(): nil},
ownChainTd: map[common.Hash]*big.Int{genesis.Hash(): genesis.Difficulty()},
peerHashes: make(map[string][]common.Hash),
peerHeaders: make(map[string]map[common.Hash]*types.Header),
peerBlocks: make(map[string]map[common.Hash]*types.Block),
peerReceipts: make(map[string]map[common.Hash]types.Receipts),
peerChainTds: make(map[string]map[common.Hash]*big.Int),
peerMissingStates: make(map[string]map[common.Hash]bool),
}
tester.stateDb, _ = ethdb.NewMemDatabase()
tester.stateDb.Put(genesis.Root().Bytes(), []byte{0x00})
@ -408,6 +411,7 @@ func (dl *downloadTester) newSlowPeer(id string, version int, hashes []common.Ha
dl.peerBlocks[id] = make(map[common.Hash]*types.Block)
dl.peerReceipts[id] = make(map[common.Hash]types.Receipts)
dl.peerChainTds[id] = make(map[common.Hash]*big.Int)
dl.peerMissingStates[id] = make(map[common.Hash]bool)
genesis := hashes[len(hashes)-1]
if header := headers[genesis]; header != nil {
@ -648,7 +652,9 @@ func (dl *downloadTester) peerGetNodeDataFn(id string, delay time.Duration) func
results := make([][]byte, 0, len(hashes))
for _, hash := range hashes {
if data, err := testdb.Get(hash.Bytes()); err == nil {
results = append(results, data)
if !dl.peerMissingStates[id][hash] {
results = append(results, data)
}
}
}
go dl.downloader.DeliverNodeData(id, results)
@ -1288,7 +1294,7 @@ func testInvalidHeaderRollback(t *testing.T, protocol int, mode SyncMode) {
tester.newPeer("withhold-attack", protocol, hashes, headers, blocks, receipts)
missing = 3*fsHeaderSafetyNet + MaxHeaderFetch + 1
tester.downloader.noFast = false
tester.downloader.fsPivotFails = 0
tester.downloader.syncInitHook = func(uint64, uint64) {
for i := missing; i <= len(hashes); i++ {
delete(tester.peerHeaders["withhold-attack"], hashes[len(hashes)-i])
@ -1307,6 +1313,8 @@ func testInvalidHeaderRollback(t *testing.T, protocol int, mode SyncMode) {
t.Errorf("fast sync pivot block #%d not rolled back", head)
}
}
tester.downloader.fsPivotFails = fsCriticalTrials
// Synchronise with the valid peer and make sure sync succeeds. Since the last
// rollback should also disable fast syncing for this process, verify that we
// did a fresh full sync. Note, we can't assert anything about the receipts
@ -1734,7 +1742,7 @@ 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:
@ -1749,3 +1757,41 @@ func testDeliverHeadersHang(t *testing.T, protocol int, mode SyncMode) {
}
}
}
// Tests that if fast sync aborts in the critical section, it can restart a few
// times before giving up.
func TestFastCriticalRestarts63(t *testing.T) { testFastCriticalRestarts(t, 63) }
func TestFastCriticalRestarts64(t *testing.T) { testFastCriticalRestarts(t, 64) }
func testFastCriticalRestarts(t *testing.T, protocol int) {
t.Parallel()
// Create a large enough blockchin to actually fast sync on
targetBlocks := fsMinFullBlocks + 2*fsPivotInterval - 15
hashes, headers, blocks, receipts := makeChain(targetBlocks, 0, genesis, nil, false)
// Create a tester peer with the critical section state roots missing (force failures)
tester := newTester()
tester.newPeer("peer", protocol, hashes, headers, blocks, receipts)
for i := 0; i < fsPivotInterval; i++ {
tester.peerMissingStates["peer"][headers[hashes[fsMinFullBlocks+i]].Root] = true
}
// Synchronise with the peer a few times and make sure they fail until the retry limit
for i := 0; i < fsCriticalTrials; i++ {
// Attempt a sync and ensure it fails properly
if err := tester.sync("peer", nil, FastSync); err == nil {
t.Fatalf("failing fast sync succeeded: %v", err)
}
// If it's the first failure, pivot should be locked => reenable all others to detect pivot changes
if i == 0 {
tester.peerMissingStates["peer"] = map[common.Hash]bool{tester.downloader.fsPivotLock.Root: true}
}
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 {
t.Fatalf("failed to synchronise blocks in slow sync: %v", err)
}
assertOwnChain(t, tester, targetBlocks+1)
}

View file

@ -23,6 +23,7 @@ import (
"errors"
"fmt"
"math"
"strings"
"sync"
"sync/atomic"
"time"
@ -31,8 +32,8 @@ 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 +69,8 @@ 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 +293,47 @@ 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 +367,14 @@ 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 +409,10 @@ 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 +575,40 @@ 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([]time.Duration, 0, len(ps.peers))
for _, p := range ps.peers {
p.lock.RLock()
rtts = append(rtts, p.rtt)
p.lock.RUnlock()
}
// Sort into ascending order and retrieve the median
for i := 0; i < len(rtts); i++ {
for j := i + 1; j < len(rtts); j++ {
if rtts[i] > rtts[j] {
rtts[i], rtts[j] = rtts[j], rtts[i]
}
}
}
median := rttMaxEstimate
if qosTuningPeers <= len(rtts) {
median = rtts[qosTuningPeers/2] // Median of our tuning peers
} else if len(rtts) > 0 {
median = 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
}

View file

@ -59,7 +59,9 @@ type blockFetcherFn func([]common.Hash) error
type ProtocolManager struct {
networkId int
fastSync uint32
fastSync uint32 // Flag whether fast sync is still enabled (no transactions, fast sync algo)
synced uint32 // Flag whether we're considered synchronised (enables transaction processing)
txpool txPool
blockchain *core.BlockChain
chaindb ethdb.Database
@ -161,7 +163,11 @@ func NewProtocolManager(config *core.ChainConfig, fastSync bool, networkId int,
heighter := func() uint64 {
return blockchain.CurrentBlock().NumberU64()
}
manager.fetcher = fetcher.New(blockchain.GetBlock, validator, manager.BroadcastBlock, heighter, manager.insertChain, manager.removePeer)
inserter := func(blocks types.Blocks) (int, error) {
atomic.StoreUint32(&manager.synced, 1) // Mark initial sync done on any fetcher import
return manager.insertChain(blocks)
}
manager.fetcher = fetcher.New(blockchain.GetBlock, validator, manager.BroadcastBlock, heighter, inserter, manager.removePeer)
if blockchain.Genesis().Hash().Hex() == defaultGenesisHash && networkId == 1 {
glog.V(logger.Debug).Infoln("Bad Block Reporting is enabled")
@ -698,8 +704,8 @@ func (pm *ProtocolManager) handleMsg(p *peer) error {
}
case msg.Code == TxMsg:
// Transactions arrived, make sure we have a valid chain to handle them
if atomic.LoadUint32(&pm.fastSync) == 1 {
// Transactions arrived, make sure we have a valid and fresh chain to handle them
if atomic.LoadUint32(&pm.fastSync) == 1 || atomic.LoadUint32(&pm.synced) == 0 {
break
}
// Transactions can be processed, parse all of them and deliver to the pool

View file

@ -97,6 +97,7 @@ func TestRecvTransactions63(t *testing.T) { testRecvTransactions(t, 63) }
func testRecvTransactions(t *testing.T, protocol int) {
txAdded := make(chan []*types.Transaction)
pm := newTestProtocolManagerMust(t, false, 0, nil, txAdded)
pm.synced = 1 // mark synced to accept transactions
p, _ := newTestPeer("peer", protocol, pm, true)
defer pm.Stop()
defer p.close()

View file

@ -174,6 +174,8 @@ func (pm *ProtocolManager) synchronise(peer *peer) {
if err := pm.downloader.Synchronise(peer.id, peer.Head(), peer.Td(), mode); err != nil {
return
}
atomic.StoreUint32(&pm.synced, 1) // Mark initial sync done
// If fast sync was enabled, and we synced up, disable it
if atomic.LoadUint32(&pm.fastSync) == 1 {
// Disable fast sync if we indeed have something in our chain