From 1e1865b73f6b0d2fef656d2f37e20e41d13a5ef0 Mon Sep 17 00:00:00 2001 From: Martin Holst Swende Date: Wed, 5 Feb 2020 13:12:09 +0100 Subject: [PATCH] core: implement background trie prefetcher Squashed from the following commits: core/state: lazily init snapshot storage map core/state: fix flawed meter on storage reads core/state: make statedb/stateobjects reuse a hasher core/blockchain, core/state: implement new trie prefetcher core: make trie prefetcher deliver tries to statedb core/state: refactor trie_prefetcher, export storage tries blockchain: re-enable the next-block-prefetcher state: remove panics in trie prefetcher core/state/trie_prefetcher: address some review concerns sq --- core/blockchain.go | 27 +++- core/state/database.go | 12 +- core/state/state_object.go | 72 +++++++--- core/state/statedb.go | 45 +++++- core/state/trie_prefetcher.go | 249 ++++++++++++++++++++++++++++++++++ crypto/crypto.go | 17 ++- crypto/crypto_test.go | 7 + 7 files changed, 395 insertions(+), 34 deletions(-) create mode 100644 core/state/trie_prefetcher.go diff --git a/core/blockchain.go b/core/blockchain.go index b8f483b85e..ccb99bded5 100644 --- a/core/blockchain.go +++ b/core/blockchain.go @@ -201,11 +201,12 @@ type BlockChain struct { running int32 // 0 if chain is running, 1 when stopped procInterrupt int32 // interrupt signaler for block processing - engine consensus.Engine - validator Validator // Block and state validator interface - prefetcher Prefetcher // Block state prefetcher interface - processor Processor // Block transaction processor interface - vmConfig vm.Config + engine consensus.Engine + validator Validator // Block and state validator interface + triePrefetcher *state.TriePrefetcher // Trie prefetcher interface + prefetcher Prefetcher + processor Processor // Block transaction processor interface + vmConfig vm.Config shouldPreserve func(*types.Block) bool // Function used to determine whether should preserve the given block. terminateInsert func(common.Hash, uint64) bool // Testing hook used to terminate ancient receipt chain insertion. @@ -249,6 +250,15 @@ func NewBlockChain(db ethdb.Database, cacheConfig *CacheConfig, chainConfig *par } bc.validator = NewBlockValidator(chainConfig, bc, engine) bc.prefetcher = newStatePrefetcher(chainConfig, bc, engine) + tp := state.NewTriePrefetcher(bc.stateCache) + + bc.wg.Add(1) + go func() { + tp.Loop() + bc.wg.Done() + }() + bc.triePrefetcher = tp + bc.processor = NewStateProcessor(chainConfig, bc, engine) var err error @@ -991,6 +1001,9 @@ func (bc *BlockChain) Stop() { bc.scope.Close() close(bc.quit) bc.StopInsert() + if bc.triePrefetcher != nil { + bc.triePrefetcher.Close() + } bc.wg.Wait() // Ensure that the entirety of the state snapshot is journalled to disk. @@ -1857,6 +1870,7 @@ func (bc *BlockChain) insertChain(chain types.Blocks, verifySeals bool) (int, er parent = bc.GetHeader(block.ParentHash(), block.NumberU64()-1) } statedb, err := state.New(parent.Root, bc.stateCache, bc.snaps) + statedb.UsePrefetcher(bc.triePrefetcher) if err != nil { return it.index, err } @@ -1891,8 +1905,7 @@ func (bc *BlockChain) insertChain(chain types.Blocks, verifySeals bool) (int, er storageUpdateTimer.Update(statedb.StorageUpdates) // Storage updates are complete, we can mark them snapshotAccountReadTimer.Update(statedb.SnapshotAccountReads) // Account reads are complete, we can mark them snapshotStorageReadTimer.Update(statedb.SnapshotStorageReads) // Storage reads are complete, we can mark them - - triehash := statedb.AccountHashes + statedb.StorageHashes // Save to not double count in validation + triehash := statedb.AccountHashes + statedb.StorageHashes // Save to not double count in validation trieproc := statedb.SnapshotAccountReads + statedb.AccountReads + statedb.AccountUpdates trieproc += statedb.SnapshotStorageReads + statedb.StorageReads + statedb.StorageUpdates diff --git a/core/state/database.go b/core/state/database.go index 83f7b2a839..1a06e33409 100644 --- a/core/state/database.go +++ b/core/state/database.go @@ -129,12 +129,20 @@ type cachingDB struct { // OpenTrie opens the main account trie at a specific root hash. func (db *cachingDB) OpenTrie(root common.Hash) (Trie, error) { - return trie.NewSecure(root, db.db) + tr, err := trie.NewSecure(root, db.db) + if err != nil { + return nil, err + } + return tr, nil } // OpenStorageTrie opens the storage trie of an account. func (db *cachingDB) OpenStorageTrie(addrHash, root common.Hash) (Trie, error) { - return trie.NewSecure(root, db.db) + tr, err := trie.NewSecure(root, db.db) + if err != nil { + return nil, err + } + return tr, nil } // CopyTrie returns an independent copy of the given trie. diff --git a/core/state/state_object.go b/core/state/state_object.go index d0d3b4513e..43c5074d92 100644 --- a/core/state/state_object.go +++ b/core/state/state_object.go @@ -157,11 +157,20 @@ func (s *stateObject) touch() { func (s *stateObject) getTrie(db Database) Trie { if s.trie == nil { - var err error - s.trie, err = db.OpenStorageTrie(s.addrHash, s.data.Root) - if err != nil { - s.trie, _ = db.OpenStorageTrie(s.addrHash, common.Hash{}) - s.setError(fmt.Errorf("can't create storage trie: %v", err)) + // Try fetching from prefetcher first + // We don't prefetch empty tries + if s.data.Root != emptyRoot && s.db.prefetcher != nil { + // When the miner is creating the pending state, there is no + // prefetcher + s.trie = s.db.prefetcher.GetTrie(s.data.Root) + } + if s.trie == nil { + var err error + s.trie, err = db.OpenStorageTrie(s.addrHash, s.data.Root) + if err != nil { + s.trie, _ = db.OpenStorageTrie(s.addrHash, common.Hash{}) + s.setError(fmt.Errorf("can't create storage trie: %v", err)) + } } } return s.trie @@ -197,12 +206,24 @@ func (s *stateObject) GetCommittedState(db Database, key common.Hash) common.Has } // If no live objects are available, attempt to use snapshots var ( - enc []byte - err error + enc []byte + err error + meter *time.Duration ) + readStart := time.Now() + if metrics.EnabledExpensive { + // If the snap is 'under construction', the first lookup may fail. If that + // happens, we don't want to double-count the time elapsed. Thus this + // dance with the metering. + defer func() { + if meter != nil { + *meter += time.Since(readStart) + } + }() + } if s.db.snap != nil { if metrics.EnabledExpensive { - defer func(start time.Time) { s.db.SnapshotStorageReads += time.Since(start) }(time.Now()) + meter = &s.db.SnapshotStorageReads } // If the object was destructed in *this* block (and potentially resurrected), // the storage has been cleared out, and we should *not* consult the previous @@ -217,8 +238,14 @@ func (s *stateObject) GetCommittedState(db Database, key common.Hash) common.Has } // If snapshot unavailable or reading from it failed, load from the database if s.db.snap == nil || err != nil { + if meter != nil { + // If we already spent time checking the snapshot, account for it + // and reset the readStart + *meter += time.Since(readStart) + readStart = time.Now() + } if metrics.EnabledExpensive { - defer func(start time.Time) { s.db.StorageReads += time.Since(start) }(time.Now()) + meter = &s.db.StorageReads } if enc, err = s.getTrie(db).TryGet(key.Bytes()); err != nil { s.setError(err) @@ -283,8 +310,13 @@ func (s *stateObject) setState(key, value common.Hash) { // finalise moves all dirty storage slots into the pending area to be hashed or // committed later. It is invoked at the end of every transaction. func (s *stateObject) finalise() { + trieChanges := make([]common.Hash, 0, len(s.dirtyStorage)) for key, value := range s.dirtyStorage { s.pendingStorage[key] = value + trieChanges = append(trieChanges, key) + } + if len(trieChanges) > 0 && s.db.prefetcher != nil && s.data.Root != emptyRoot { + s.db.prefetcher.PrefetchStorage(s.data.Root, trieChanges) } if len(s.dirtyStorage) > 0 { s.dirtyStorage = make(Storage) @@ -303,18 +335,11 @@ func (s *stateObject) updateTrie(db Database) Trie { if metrics.EnabledExpensive { defer func(start time.Time) { s.db.StorageUpdates += time.Since(start) }(time.Now()) } - // Retrieve the snapshot storage map for the object + // The snapshot storage map for the object var storage map[common.Hash][]byte - if s.db.snap != nil { - // Retrieve the old storage map, if available, create a new one otherwise - storage = s.db.snapStorage[s.addrHash] - if storage == nil { - storage = make(map[common.Hash][]byte) - s.db.snapStorage[s.addrHash] = storage - } - } // Insert all the pending updates into the trie tr := s.getTrie(db) + hasher := s.db.hasher for key, value := range s.pendingStorage { // Skip noop changes, persist actual changes if value == s.originStorage[key] { @@ -331,8 +356,15 @@ func (s *stateObject) updateTrie(db Database) Trie { s.setError(tr.TryUpdate(key[:], v)) } // If state snapshotting is active, cache the data til commit - if storage != nil { - storage[crypto.Keccak256Hash(key[:])] = v // v will be nil if value is 0x00 + if s.db.snap != nil { + if storage == nil { + // Retrieve the old storage map, if available, create a new one otherwise + if storage = s.db.snapStorage[s.addrHash]; storage == nil { + storage = make(map[common.Hash][]byte) + s.db.snapStorage[s.addrHash] = storage + } + } + storage[crypto.HashData(hasher, key[:])] = v // v will be nil if value is 0x00 } } if len(s.pendingStorage) > 0 { diff --git a/core/state/statedb.go b/core/state/statedb.go index a9d1de2e06..ce50962e8b 100644 --- a/core/state/statedb.go +++ b/core/state/statedb.go @@ -62,8 +62,11 @@ func (n *proofList) Delete(key []byte) error { // * Contracts // * Accounts type StateDB struct { - db Database - trie Trie + db Database + prefetcher *TriePrefetcher + originalRoot common.Hash // The pre-state root, before any changes were made + trie Trie + hasher crypto.KeccakState snaps *snapshot.Tree snap snapshot.Snapshot @@ -125,6 +128,7 @@ func New(root common.Hash, db Database, snaps *snapshot.Tree) (*StateDB, error) sdb := &StateDB{ db: db, trie: tr, + originalRoot: root, snaps: snaps, stateObjects: make(map[common.Address]*stateObject), stateObjectsPending: make(map[common.Address]struct{}), @@ -133,6 +137,7 @@ func New(root common.Hash, db Database, snaps *snapshot.Tree) (*StateDB, error) preimages: make(map[common.Hash][]byte), journal: newJournal(), accessList: newAccessList(), + hasher: crypto.NewKeccakState(), } if sdb.snaps != nil { if sdb.snap = sdb.snaps.Snapshot(root); sdb.snap != nil { @@ -144,6 +149,13 @@ func New(root common.Hash, db Database, snaps *snapshot.Tree) (*StateDB, error) return sdb, nil } +func (s *StateDB) UsePrefetcher(prefetcher *TriePrefetcher) { + if prefetcher != nil { + s.prefetcher = prefetcher + s.prefetcher.Resume(s.originalRoot) + } +} + // setError remembers the first non-nil error it is called with. func (s *StateDB) setError(err error) { if s.dbErr == nil { @@ -532,7 +544,7 @@ func (s *StateDB) getDeletedStateObject(addr common.Address) *stateObject { defer func(start time.Time) { s.SnapshotAccountReads += time.Since(start) }(time.Now()) } var acc *snapshot.Account - if acc, err = s.snap.Account(crypto.Keccak256Hash(addr.Bytes())); err == nil { + if acc, err = s.snap.Account(crypto.HashData(s.hasher, addr.Bytes())); err == nil { if acc == nil { return nil } @@ -675,6 +687,7 @@ func (s *StateDB) Copy() *StateDB { logSize: s.logSize, preimages: make(map[common.Hash][]byte, len(s.preimages)), journal: newJournal(), + hasher: crypto.NewKeccakState(), } // Copy the dirty states, logs, and preimages for addr := range s.journal.dirties { @@ -760,6 +773,7 @@ func (s *StateDB) GetRefund() uint64 { // the journal as well as the refunds. Finalise, however, will not push any updates // into the tries just yet. Only IntermediateRoot or Commit will do that. func (s *StateDB) Finalise(deleteEmptyObjects bool) { + var addressesToPrefetch []common.Address for addr := range s.journal.dirties { obj, exist := s.stateObjects[addr] if !exist { @@ -788,7 +802,17 @@ func (s *StateDB) Finalise(deleteEmptyObjects bool) { } s.stateObjectsPending[addr] = struct{}{} s.stateObjectsDirty[addr] = struct{}{} + // At this point, also ship the address off to the precacher. The precacher + // will start loading tries, and when the change is eventually committed, + // the commit-phase will be a lot faster + if s.prefetcher != nil { + addressesToPrefetch = append(addressesToPrefetch, addr) + } } + if s.prefetcher != nil { + s.prefetcher.PrefetchAddresses(addressesToPrefetch) + } + // Invalidate journal because reverting across transactions is not allowed. s.clearJournalAndRefund() } @@ -800,6 +824,21 @@ func (s *StateDB) IntermediateRoot(deleteEmptyObjects bool) common.Hash { // Finalise all the dirty storage states and write them into the tries s.Finalise(deleteEmptyObjects) + // Now we're about to start to write changes to the trie. The trie is so + // far _untouched_. We can check with the prefetcher, if it can give us + // a trie which has the same root, but also has some content loaded into it. + // If so, use that one instead. + if s.prefetcher != nil { + s.prefetcher.Pause() + // We only want to do this _once_, if someone calls IntermediateRoot again, + // we shouldn't fetch the trie again + if s.originalRoot != (common.Hash{}) { + if trie := s.prefetcher.GetTrie(s.originalRoot); trie != nil { + s.trie = trie + } + s.originalRoot = common.Hash{} + } + } for addr := range s.stateObjectsPending { obj := s.stateObjects[addr] if obj.deleted { diff --git a/core/state/trie_prefetcher.go b/core/state/trie_prefetcher.go new file mode 100644 index 0000000000..8a1aab3253 --- /dev/null +++ b/core/state/trie_prefetcher.go @@ -0,0 +1,249 @@ +// Copyright 2020 The go-ethereum Authors +// This file is part of the go-ethereum library. +// +// The go-ethereum library is free software: you can redistribute it and/or modify +// it under the terms of the GNU Lesser General Public License as published by +// the Free Software Foundation, either version 3 of the License, or +// (at your option) any later version. +// +// The go-ethereum library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public License +// along with the go-ethereum library. If not, see . + +package state + +import ( + "github.com/ethereum/go-ethereum/common" + "github.com/ethereum/go-ethereum/log" + "github.com/ethereum/go-ethereum/metrics" +) + +var ( + // trieDeliveryMeter counts how many times the prefetcher was unable to supply + // the statedb with a prefilled trie. This meter should be zero -- if it's not, that + // needs to be investigated + trieDeliveryMissMeter = metrics.NewRegisteredMeter("trie/prefetch/deliverymiss", nil) + + triePrefetchFetchMeter = metrics.NewRegisteredMeter("trie/prefetch/fetch", nil) + triePrefetchSkipMeter = metrics.NewRegisteredMeter("trie/prefetch/skip", nil) + triePrefetchDropMeter = metrics.NewRegisteredMeter("trie/prefetch/drop", nil) +) + +// TriePrefetcher is an active prefetcher, which receives accounts or storage +// items on two channels, and does trie-loading of the items. +// The goal is to get as much useful content into the caches as possible +type TriePrefetcher struct { + requestCh chan (fetchRequest) // Chan to receive requests for data to fetch + cmdCh chan (*cmd) // Chan to control activity, pause/new root + quitCh chan (struct{}) + deliveryCh chan (struct{}) + db Database + + paused bool + + storageTries map[common.Hash]Trie + accountTrie Trie + accountTrieRoot common.Hash +} + +func NewTriePrefetcher(db Database) *TriePrefetcher { + return &TriePrefetcher{ + requestCh: make(chan fetchRequest, 200), + cmdCh: make(chan *cmd), + quitCh: make(chan struct{}), + deliveryCh: make(chan struct{}), + db: db, + } +} + +type cmd struct { + root common.Hash +} + +type fetchRequest struct { + slots []common.Hash + storageRoot *common.Hash + addresses []common.Address +} + +func (p *TriePrefetcher) Loop() { + var ( + accountTrieRoot common.Hash + accountTrie Trie + storageTries map[common.Hash]Trie + + err error + // Some tracking of performance + skipped int64 + fetched int64 + + paused = true + ) + // The prefetcher loop has two distinct phases: + // 1: Paused: when in this state, the accumulated tries are accessible to outside + // callers. + // 2: Active prefetching, awaiting slots and accounts to prefetch + for { + select { + case <-p.quitCh: + return + case cmd := <-p.cmdCh: + // Clear out any old requests + drain: + for { + select { + case req := <-p.requestCh: + if req.slots != nil { + skipped += int64(len(req.slots)) + } else { + skipped += int64(len(req.addresses)) + } + default: + break drain + } + } + if paused { + // Clear old data + p.storageTries = nil + p.accountTrie = nil + p.accountTrieRoot = common.Hash{} + // Resume again + storageTries = make(map[common.Hash]Trie) + accountTrieRoot = cmd.root + accountTrie, err = p.db.OpenTrie(accountTrieRoot) + if err != nil { + log.Error("Trie prefetcher failed opening trie", "root", accountTrieRoot, "err", err) + } + if accountTrieRoot == (common.Hash{}) { + log.Error("Trie prefetcher unpaused with bad root") + } + paused = false + } else { + // Update metrics at new block events + triePrefetchFetchMeter.Mark(fetched) + triePrefetchSkipMeter.Mark(skipped) + fetched, skipped = 0, 0 + // Make the tries accessible + p.accountTrie = accountTrie + p.storageTries = storageTries + p.accountTrieRoot = accountTrieRoot + if cmd.root != (common.Hash{}) { + log.Error("Trie prefetcher paused with non-empty root") + } + paused = true + } + p.deliveryCh <- struct{}{} + case req := <-p.requestCh: + if paused { + continue + } + if sRoot := req.storageRoot; sRoot != nil { + // Storage slots to fetch + var ( + storageTrie Trie + err error + ) + if storageTrie = storageTries[*sRoot]; storageTrie == nil { + if storageTrie, err = p.db.OpenTrie(*sRoot); err != nil { + log.Warn("trie prefetcher failed opening storage trie", "root", *sRoot, "err", err) + skipped += int64(len(req.slots)) + continue + } + storageTries[*sRoot] = storageTrie + } + for _, key := range req.slots { + storageTrie.TryGet(key[:]) + } + fetched += int64(len(req.slots)) + } else { // an account + for _, addr := range req.addresses { + accountTrie.TryGet(addr[:]) + } + fetched += int64(len(req.addresses)) + } + } + } +} + +// Close stops the prefetcher +func (p *TriePrefetcher) Close() { + if p.quitCh != nil { + close(p.quitCh) + p.quitCh = nil + } +} + +// Resume causes the prefetcher to clear out old data, and get ready to +// fetch data concerning the new root +func (p *TriePrefetcher) Resume(root common.Hash) { + p.paused = false + p.cmdCh <- &cmd{ + root: root, + } + // Wait for it + <-p.deliveryCh +} + +// Pause causes the prefetcher to pause prefetching, and make tries +// accessible to callers via GetTrie +func (p *TriePrefetcher) Pause() { + if p.paused { + return + } + p.paused = true + p.cmdCh <- &cmd{ + root: common.Hash{}, + } + // Wait for it + <-p.deliveryCh +} + +// PrefetchAddresses adds an address for prefetching +func (p *TriePrefetcher) PrefetchAddresses(addresses []common.Address) { + cmd := fetchRequest{ + addresses: addresses, + } + // We do an async send here, to not cause the caller to block + //p.requestCh <- cmd + select { + case p.requestCh <- cmd: + default: + triePrefetchDropMeter.Mark(int64(len(addresses))) + } +} + +// PrefetchStorage adds a storage root and a set of keys for prefetching +func (p *TriePrefetcher) PrefetchStorage(root common.Hash, slots []common.Hash) { + cmd := fetchRequest{ + storageRoot: &root, + slots: slots, + } + // We do an async send here, to not cause the caller to block + //p.requestCh <- cmd + select { + case p.requestCh <- cmd: + default: + triePrefetchDropMeter.Mark(int64(len(slots))) + } +} + +// GetTrie returns the trie matching the root hash, or nil if the prefetcher +// doesn't have it. +func (p *TriePrefetcher) GetTrie(root common.Hash) Trie { + if root == p.accountTrieRoot { + return p.accountTrie + } + if storageTrie, ok := p.storageTries[root]; ok { + // Two accounts may well have the same storage root, but we cannot allow + // them both to make updates to the same trie instance. Therefore, + // we need to either delete the trie now, or deliver a copy of the trie. + delete(p.storageTries, root) + return storageTrie + } + trieDeliveryMissMeter.Mark(1) + return nil +} diff --git a/crypto/crypto.go b/crypto/crypto.go index a4a49136a8..40969a2895 100644 --- a/crypto/crypto.go +++ b/crypto/crypto.go @@ -60,10 +60,23 @@ type KeccakState interface { Read([]byte) (int, error) } +// NewKeccakState creates a new KeccakState +func NewKeccakState() KeccakState { + return sha3.NewLegacyKeccak256().(KeccakState) +} + +// HashData hashes the provided data using the KeccakState and returns a 32 byte hash +func HashData(kh KeccakState, data []byte) (h common.Hash) { + kh.Reset() + kh.Write(data) + kh.Read(h[:]) + return h +} + // Keccak256 calculates and returns the Keccak256 hash of the input data. func Keccak256(data ...[]byte) []byte { b := make([]byte, 32) - d := sha3.NewLegacyKeccak256().(KeccakState) + d := NewKeccakState() for _, b := range data { d.Write(b) } @@ -74,7 +87,7 @@ func Keccak256(data ...[]byte) []byte { // Keccak256Hash calculates and returns the Keccak256 hash of the input data, // converting it to an internal Hash data structure. func Keccak256Hash(data ...[]byte) (h common.Hash) { - d := sha3.NewLegacyKeccak256().(KeccakState) + d := NewKeccakState() for _, b := range data { d.Write(b) } diff --git a/crypto/crypto_test.go b/crypto/crypto_test.go index f71ae8232a..f9b0d3e834 100644 --- a/crypto/crypto_test.go +++ b/crypto/crypto_test.go @@ -42,6 +42,13 @@ func TestKeccak256Hash(t *testing.T) { checkhash(t, "Sha3-256-array", func(in []byte) []byte { h := Keccak256Hash(in); return h[:] }, msg, exp) } +func TestKeccak256Hasher(t *testing.T) { + msg := []byte("abc") + exp, _ := hex.DecodeString("4e03657aea45a94fc7d47ba826c8d667c0d1e6e33a64a036ec44f58fa12d6c45") + hasher := NewKeccakState() + checkhash(t, "Sha3-256-array", func(in []byte) []byte { h := HashData(hasher, in); return h[:] }, msg, exp) +} + func TestToECDSAErrors(t *testing.T) { if _, err := HexToECDSA("0000000000000000000000000000000000000000000000000000000000000000"); err == nil { t.Fatal("HexToECDSA should've returned error")