core, trie: intermediate mempool between trie and database (#15857)

This commit reduces database I/O by not writing every state trie to disk.
This commit is contained in:
Péter Szilágyi
2018-02-05 18:40:32 +02:00
committed by Felix Lange
parent 59336283c0
commit 55599ee95d
69 changed files with 1958 additions and 1164 deletions

View File

@ -18,10 +18,8 @@
package downloader
import (
"crypto/rand"
"errors"
"fmt"
"math"
"math/big"
"sync"
"sync/atomic"
@ -61,12 +59,11 @@ var (
maxHeadersProcess = 2048 // Number of header download results to import at once into the chain
maxResultsProcess = 2048 // Number of content download results to import at once into the chain
fsHeaderCheckFrequency = 100 // Verification frequency of the downloaded headers during fast sync
fsHeaderSafetyNet = 2048 // Number of headers to discard in case a chain violation is detected
fsHeaderForceVerify = 24 // Number of headers to verify before and after the pivot to accept it
fsPivotInterval = 256 // Number of headers out of which to randomize the pivot point
fsMinFullBlocks = 64 // Number of blocks to retrieve fully even in fast sync
fsCriticalTrials = uint32(32) // Number of times to retry in the cricical section before bailing
fsHeaderCheckFrequency = 100 // Verification frequency of the downloaded headers during fast sync
fsHeaderSafetyNet = 2048 // Number of headers to discard in case a chain violation is detected
fsHeaderForceVerify = 24 // Number of headers to verify before and after the pivot to accept it
fsHeaderContCheck = 3 * time.Second // Time interval to check for header continuations during state download
fsMinFullBlocks = 64 // Number of blocks to retrieve fully even in fast sync
)
var (
@ -102,9 +99,6 @@ type Downloader struct {
peers *peerSet // Set of active peers from which download can proceed
stateDB ethdb.Database
fsPivotLock *types.Header // Pivot header on critical section entry (cannot change between retries)
fsPivotFails uint32 // Number of subsequent 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)
@ -124,6 +118,7 @@ type Downloader struct {
synchroniseMock func(id string, hash common.Hash) error // Replacement for synchronise during testing
synchronising int32
notified int32
committed int32
// Channels
headerCh chan dataPack // [eth/62] Channel receiving inbound block headers
@ -156,7 +151,7 @@ type Downloader struct {
// LightChain encapsulates functions required to synchronise a light chain.
type LightChain interface {
// HasHeader verifies a header's presence in the local chain.
HasHeader(h common.Hash, number uint64) bool
HasHeader(common.Hash, uint64) bool
// GetHeaderByHash retrieves a header from the local chain.
GetHeaderByHash(common.Hash) *types.Header
@ -179,7 +174,7 @@ type BlockChain interface {
LightChain
// HasBlockAndState verifies block and associated states' presence in the local chain.
HasBlockAndState(common.Hash) bool
HasBlockAndState(common.Hash, uint64) bool
// GetBlockByHash retrieves a block from the local chain.
GetBlockByHash(common.Hash) *types.Block
@ -391,9 +386,7 @@ 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 && atomic.LoadUint32(&d.fsPivotFails) >= fsCriticalTrials {
d.mode = FullSync
}
// Retrieve the origin peer and initiate the downloading process
p := d.peers.Peer(id)
if p == nil {
@ -441,57 +434,40 @@ func (d *Downloader) syncWithPeer(p *peerConnection, hash common.Hash, td *big.I
d.syncStatsChainHeight = height
d.syncStatsLock.Unlock()
// Initiate the sync using a concurrent header and content retrieval algorithm
// Ensure our origin point is below any fast sync pivot point
pivot := uint64(0)
switch d.mode {
case LightSync:
pivot = height
case FastSync:
// Calculate the new fast/slow sync pivot point
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()
}
if d.mode == FastSync {
if height <= uint64(fsMinFullBlocks) {
origin = 0
} 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 {
if pivot > 0 {
pivot = height - uint64(fsMinFullBlocks)
if pivot <= origin {
origin = pivot - 1
} else {
origin = 0
}
}
log.Debug("Fast syncing until pivot block", "pivot", pivot)
}
d.queue.Prepare(origin+1, d.mode, pivot, latest)
d.committed = 1
if d.mode == FastSync && pivot != 0 {
d.committed = 0
}
// Initiate the sync using a concurrent header and content retrieval algorithm
d.queue.Prepare(origin+1, d.mode)
if d.syncInitHook != nil {
d.syncInitHook(origin, height)
}
fetchers := []func() error{
func() error { return d.fetchHeaders(p, origin+1) }, // Headers are always retrieved
func() error { return d.fetchBodies(origin + 1) }, // Bodies are retrieved during normal and fast sync
func() error { return d.fetchReceipts(origin + 1) }, // Receipts are retrieved during fast sync
func() error { return d.processHeaders(origin+1, td) },
func() error { return d.fetchHeaders(p, origin+1, pivot) }, // Headers are always retrieved
func() error { return d.fetchBodies(origin + 1) }, // Bodies are retrieved during normal and fast sync
func() error { return d.fetchReceipts(origin + 1) }, // Receipts are retrieved during fast sync
func() error { return d.processHeaders(origin+1, pivot, td) },
}
if d.mode == FastSync {
fetchers = append(fetchers, func() error { return d.processFastSyncContent(latest) })
} else if d.mode == FullSync {
fetchers = append(fetchers, d.processFullSyncContent)
}
err = d.spawnSync(fetchers)
if err != nil && d.mode == FastSync && d.fsPivotLock != nil {
// If sync failed in the critical section, bump the fail counter.
atomic.AddUint32(&d.fsPivotFails, 1)
}
return err
return d.spawnSync(fetchers)
}
// spawnSync runs d.process and all given fetcher functions to completion in
@ -671,7 +647,7 @@ func (d *Downloader) findAncestor(p *peerConnection, height uint64) (uint64, err
continue
}
// Otherwise check if we already know the header or not
if (d.mode == FullSync && d.blockchain.HasBlockAndState(headers[i].Hash())) || (d.mode != FullSync && d.lightchain.HasHeader(headers[i].Hash(), headers[i].Number.Uint64())) {
if (d.mode == FullSync && d.blockchain.HasBlockAndState(headers[i].Hash(), headers[i].Number.Uint64())) || (d.mode != FullSync && d.lightchain.HasHeader(headers[i].Hash(), headers[i].Number.Uint64())) {
number, hash = headers[i].Number.Uint64(), headers[i].Hash()
// If every header is known, even future ones, the peer straight out lied about its head
@ -736,7 +712,7 @@ func (d *Downloader) findAncestor(p *peerConnection, height uint64) (uint64, err
arrived = true
// Modify the search interval based on the response
if (d.mode == FullSync && !d.blockchain.HasBlockAndState(headers[0].Hash())) || (d.mode != FullSync && !d.lightchain.HasHeader(headers[0].Hash(), headers[0].Number.Uint64())) {
if (d.mode == FullSync && !d.blockchain.HasBlockAndState(headers[0].Hash(), headers[0].Number.Uint64())) || (d.mode != FullSync && !d.lightchain.HasHeader(headers[0].Hash(), headers[0].Number.Uint64())) {
end = check
break
}
@ -774,7 +750,7 @@ func (d *Downloader) findAncestor(p *peerConnection, height uint64) (uint64, err
// other peers are only accepted if they map cleanly to the skeleton. If no one
// can fill in the skeleton - not even the origin peer - it's assumed invalid and
// the origin is dropped.
func (d *Downloader) fetchHeaders(p *peerConnection, from uint64) error {
func (d *Downloader) fetchHeaders(p *peerConnection, from uint64, pivot uint64) error {
p.log.Debug("Directing header downloads", "origin", from)
defer p.log.Debug("Header download terminated")
@ -825,6 +801,18 @@ func (d *Downloader) fetchHeaders(p *peerConnection, from uint64) error {
}
// If no more headers are inbound, notify the content fetchers and return
if packet.Items() == 0 {
// Don't abort header fetches while the pivot is downloading
if atomic.LoadInt32(&d.committed) == 0 && pivot <= from {
p.log.Debug("No headers, waiting for pivot commit")
select {
case <-time.After(fsHeaderContCheck):
getHeaders(from)
continue
case <-d.cancelCh:
return errCancelHeaderFetch
}
}
// Pivot done (or not in fast sync) and no more headers, terminate the process
p.log.Debug("No more headers available")
select {
case d.headerProcCh <- nil:
@ -1129,10 +1117,8 @@ func (d *Downloader) fetchParts(errCancel error, deliveryCh chan dataPack, deliv
}
if request.From > 0 {
peer.log.Trace("Requesting new batch of data", "type", kind, "from", request.From)
} else if len(request.Headers) > 0 {
peer.log.Trace("Requesting new batch of data", "type", kind, "count", len(request.Headers), "from", request.Headers[0].Number)
} else {
peer.log.Trace("Requesting new batch of data", "type", kind, "count", len(request.Hashes))
peer.log.Trace("Requesting new batch of data", "type", kind, "count", len(request.Headers), "from", request.Headers[0].Number)
}
// Fetch the chunk and make sure any errors return the hashes to the queue
if fetchHook != nil {
@ -1160,10 +1146,7 @@ func (d *Downloader) fetchParts(errCancel error, deliveryCh chan dataPack, deliv
// processHeaders takes batches of retrieved headers from an input channel and
// keeps processing and scheduling them into the header chain and downloader's
// queue until the stream ends or a failure occurs.
func (d *Downloader) processHeaders(origin uint64, td *big.Int) error {
// Calculate the pivoting point for switching from fast to slow sync
pivot := d.queue.FastSyncPivot()
func (d *Downloader) processHeaders(origin uint64, pivot uint64, td *big.Int) error {
// Keep a count of uncertain headers to roll back
rollback := []*types.Header{}
defer func() {
@ -1188,19 +1171,6 @@ func (d *Downloader) processHeaders(origin uint64, td *big.Int) error {
"header", fmt.Sprintf("%d->%d", lastHeader, d.lightchain.CurrentHeader().Number),
"fast", fmt.Sprintf("%d->%d", lastFastBlock, curFastBlock),
"block", fmt.Sprintf("%d->%d", lastBlock, curBlock))
// If we're already past the pivot point, this could be an attack, thread carefully
if rollback[len(rollback)-1].Number.Uint64() > pivot {
// If we didn't ever fail, lock in the pivot header (must! not! change!)
if atomic.LoadUint32(&d.fsPivotFails) == 0 {
for _, header := range rollback {
if header.Number.Uint64() == pivot {
log.Warn("Fast-sync pivot locked in", "number", pivot, "hash", header.Hash())
d.fsPivotLock = header
}
}
}
}
}
}()
@ -1302,13 +1272,6 @@ 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() {
log.Warn("Pivot doesn't match locked in one", "remoteNumber", pivot.Number, "remoteHash", pivot.Hash(), "localNumber", d.fsPivotLock.Number, "localHash", d.fsPivotLock.Hash())
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
@ -1343,7 +1306,7 @@ func (d *Downloader) processHeaders(origin uint64, td *big.Int) error {
// processFullSyncContent takes fetch results from the queue and imports them into the chain.
func (d *Downloader) processFullSyncContent() error {
for {
results := d.queue.WaitResults()
results := d.queue.Results(true)
if len(results) == 0 {
return nil
}
@ -1357,30 +1320,28 @@ func (d *Downloader) processFullSyncContent() error {
}
func (d *Downloader) importBlockResults(results []*fetchResult) error {
for len(results) != 0 {
// Check for any termination requests. This makes clean shutdown faster.
select {
case <-d.quitCh:
return errCancelContentProcessing
default:
}
// Retrieve the a batch of results to import
items := int(math.Min(float64(len(results)), float64(maxResultsProcess)))
first, last := results[0].Header, results[items-1].Header
log.Debug("Inserting downloaded chain", "items", len(results),
"firstnum", first.Number, "firsthash", first.Hash(),
"lastnum", last.Number, "lasthash", last.Hash(),
)
blocks := make([]*types.Block, items)
for i, result := range results[:items] {
blocks[i] = types.NewBlockWithHeader(result.Header).WithBody(result.Transactions, result.Uncles)
}
if index, err := d.blockchain.InsertChain(blocks); err != nil {
log.Debug("Downloaded item processing failed", "number", results[index].Header.Number, "hash", results[index].Header.Hash(), "err", err)
return errInvalidChain
}
// Shift the results to the next batch
results = results[items:]
// Check for any early termination requests
if len(results) == 0 {
return nil
}
select {
case <-d.quitCh:
return errCancelContentProcessing
default:
}
// Retrieve the a batch of results to import
first, last := results[0].Header, results[len(results)-1].Header
log.Debug("Inserting downloaded chain", "items", len(results),
"firstnum", first.Number, "firsthash", first.Hash(),
"lastnum", last.Number, "lasthash", last.Hash(),
)
blocks := make([]*types.Block, len(results))
for i, result := range results {
blocks[i] = types.NewBlockWithHeader(result.Header).WithBody(result.Transactions, result.Uncles)
}
if index, err := d.blockchain.InsertChain(blocks); err != nil {
log.Debug("Downloaded item processing failed", "number", results[index].Header.Number, "hash", results[index].Header.Hash(), "err", err)
return errInvalidChain
}
return nil
}
@ -1388,35 +1349,92 @@ func (d *Downloader) importBlockResults(results []*fetchResult) error {
// processFastSyncContent takes fetch results from the queue and writes them to the
// database. It also controls the synchronisation of state nodes of the pivot block.
func (d *Downloader) processFastSyncContent(latest *types.Header) error {
// Start syncing state of the reported head block.
// This should get us most of the state of the pivot block.
// Start syncing state of the reported head block. This should get us most of
// the state of the pivot block.
stateSync := d.syncState(latest.Root)
defer stateSync.Cancel()
go func() {
if err := stateSync.Wait(); err != nil {
if err := stateSync.Wait(); err != nil && err != errCancelStateFetch {
d.queue.Close() // wake up WaitResults
}
}()
pivot := d.queue.FastSyncPivot()
// Figure out the ideal pivot block. Note, that this goalpost may move if the
// sync takes long enough for the chain head to move significantly.
pivot := uint64(0)
if height := latest.Number.Uint64(); height > uint64(fsMinFullBlocks) {
pivot = height - uint64(fsMinFullBlocks)
}
// To cater for moving pivot points, track the pivot block and subsequently
// accumulated download results separatey.
var (
oldPivot *fetchResult // Locked in pivot block, might change eventually
oldTail []*fetchResult // Downloaded content after the pivot
)
for {
results := d.queue.WaitResults()
// Wait for the next batch of downloaded data to be available, and if the pivot
// block became stale, move the goalpost
results := d.queue.Results(oldPivot == nil) // Block if we're not monitoring pivot staleness
if len(results) == 0 {
return stateSync.Cancel()
// If pivot sync is done, stop
if oldPivot == nil {
return stateSync.Cancel()
}
// If sync failed, stop
select {
case <-d.cancelCh:
return stateSync.Cancel()
default:
}
}
if d.chainInsertHook != nil {
d.chainInsertHook(results)
}
if oldPivot != nil {
results = append(append([]*fetchResult{oldPivot}, oldTail...), results...)
}
// Split around the pivot block and process the two sides via fast/full sync
if atomic.LoadInt32(&d.committed) == 0 {
latest = results[len(results)-1].Header
if height := latest.Number.Uint64(); height > pivot+2*uint64(fsMinFullBlocks) {
log.Warn("Pivot became stale, moving", "old", pivot, "new", height-uint64(fsMinFullBlocks))
pivot = height - uint64(fsMinFullBlocks)
}
}
P, beforeP, afterP := splitAroundPivot(pivot, results)
if err := d.commitFastSyncData(beforeP, stateSync); err != nil {
return err
}
if P != nil {
stateSync.Cancel()
if err := d.commitPivotBlock(P); err != nil {
return err
// If new pivot block found, cancel old state retrieval and restart
if oldPivot != P {
stateSync.Cancel()
stateSync = d.syncState(P.Header.Root)
defer stateSync.Cancel()
go func() {
if err := stateSync.Wait(); err != nil && err != errCancelStateFetch {
d.queue.Close() // wake up WaitResults
}
}()
oldPivot = P
}
// Wait for completion, occasionally checking for pivot staleness
select {
case <-stateSync.done:
if stateSync.err != nil {
return stateSync.err
}
if err := d.commitPivotBlock(P); err != nil {
return err
}
oldPivot = nil
case <-time.After(time.Second):
oldTail = afterP
continue
}
}
// Fast sync done, pivot commit done, full import
if err := d.importBlockResults(afterP); err != nil {
return err
}
@ -1439,52 +1457,49 @@ func splitAroundPivot(pivot uint64, results []*fetchResult) (p *fetchResult, bef
}
func (d *Downloader) commitFastSyncData(results []*fetchResult, stateSync *stateSync) error {
for len(results) != 0 {
// Check for any termination requests.
select {
case <-d.quitCh:
return errCancelContentProcessing
case <-stateSync.done:
if err := stateSync.Wait(); err != nil {
return err
}
default:
// Check for any early termination requests
if len(results) == 0 {
return nil
}
select {
case <-d.quitCh:
return errCancelContentProcessing
case <-stateSync.done:
if err := stateSync.Wait(); err != nil {
return err
}
// Retrieve the a batch of results to import
items := int(math.Min(float64(len(results)), float64(maxResultsProcess)))
first, last := results[0].Header, results[items-1].Header
log.Debug("Inserting fast-sync blocks", "items", len(results),
"firstnum", first.Number, "firsthash", first.Hash(),
"lastnumn", last.Number, "lasthash", last.Hash(),
)
blocks := make([]*types.Block, items)
receipts := make([]types.Receipts, items)
for i, result := range results[:items] {
blocks[i] = types.NewBlockWithHeader(result.Header).WithBody(result.Transactions, result.Uncles)
receipts[i] = result.Receipts
}
if index, err := d.blockchain.InsertReceiptChain(blocks, receipts); err != nil {
log.Debug("Downloaded item processing failed", "number", results[index].Header.Number, "hash", results[index].Header.Hash(), "err", err)
return errInvalidChain
}
// Shift the results to the next batch
results = results[items:]
default:
}
// Retrieve the a batch of results to import
first, last := results[0].Header, results[len(results)-1].Header
log.Debug("Inserting fast-sync blocks", "items", len(results),
"firstnum", first.Number, "firsthash", first.Hash(),
"lastnumn", last.Number, "lasthash", last.Hash(),
)
blocks := make([]*types.Block, len(results))
receipts := make([]types.Receipts, len(results))
for i, result := range results {
blocks[i] = types.NewBlockWithHeader(result.Header).WithBody(result.Transactions, result.Uncles)
receipts[i] = result.Receipts
}
if index, err := d.blockchain.InsertReceiptChain(blocks, receipts); err != nil {
log.Debug("Downloaded item processing failed", "number", results[index].Header.Number, "hash", results[index].Header.Hash(), "err", err)
return errInvalidChain
}
return nil
}
func (d *Downloader) commitPivotBlock(result *fetchResult) error {
b := types.NewBlockWithHeader(result.Header).WithBody(result.Transactions, result.Uncles)
// Sync the pivot block state. This should complete reasonably quickly because
// we've already synced up to the reported head block state earlier.
if err := d.syncState(b.Root()).Wait(); err != nil {
block := types.NewBlockWithHeader(result.Header).WithBody(result.Transactions, result.Uncles)
log.Debug("Committing fast sync pivot as new head", "number", block.Number(), "hash", block.Hash())
if _, err := d.blockchain.InsertReceiptChain([]*types.Block{block}, []types.Receipts{result.Receipts}); err != nil {
return err
}
log.Debug("Committing fast sync pivot as new head", "number", b.Number(), "hash", b.Hash())
if _, err := d.blockchain.InsertReceiptChain([]*types.Block{b}, []types.Receipts{result.Receipts}); err != nil {
if err := d.blockchain.FastSyncCommitHead(block.Hash()); err != nil {
return err
}
return d.blockchain.FastSyncCommitHead(b.Hash())
atomic.StoreInt32(&d.committed, 1)
return nil
}
// DeliverHeaders injects a new batch of block headers received from a remote