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authorTed Yin <[email protected]>2020-09-18 13:14:29 -0400
committerGitHub <[email protected]>2020-09-18 13:14:29 -0400
commitd048937c48753d9eaef771bf71820cf95d79df26 (patch)
tree1a7f65fcd72e77092525ab01625b8b9d365e3e40 /core/state/snapshot/snapshot.go
parent7d1388c743b4ec8f4a86bea95bfada785dee83f7 (diff)
parent7d8c85cf8895b0f998d8eafb02f99d5b689fcd59 (diff)
Merge pull request #34 from ava-labs/devv0.3.0-rc.5
Dev
Diffstat (limited to 'core/state/snapshot/snapshot.go')
-rw-r--r--core/state/snapshot/snapshot.go619
1 files changed, 619 insertions, 0 deletions
diff --git a/core/state/snapshot/snapshot.go b/core/state/snapshot/snapshot.go
new file mode 100644
index 0000000..3348685
--- /dev/null
+++ b/core/state/snapshot/snapshot.go
@@ -0,0 +1,619 @@
+// Copyright 2019 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 <http://www.gnu.org/licenses/>.
+
+// Package snapshot implements a journalled, dynamic state dump.
+package snapshot
+
+import (
+ "bytes"
+ "errors"
+ "fmt"
+ "sync"
+ "sync/atomic"
+
+ "github.com/ava-labs/coreth/core/rawdb"
+ "github.com/ethereum/go-ethereum/common"
+ "github.com/ethereum/go-ethereum/ethdb"
+ "github.com/ethereum/go-ethereum/log"
+ "github.com/ethereum/go-ethereum/metrics"
+ "github.com/ethereum/go-ethereum/trie"
+)
+
+var (
+ snapshotCleanAccountHitMeter = metrics.NewRegisteredMeter("state/snapshot/clean/account/hit", nil)
+ snapshotCleanAccountMissMeter = metrics.NewRegisteredMeter("state/snapshot/clean/account/miss", nil)
+ snapshotCleanAccountInexMeter = metrics.NewRegisteredMeter("state/snapshot/clean/account/inex", nil)
+ snapshotCleanAccountReadMeter = metrics.NewRegisteredMeter("state/snapshot/clean/account/read", nil)
+ snapshotCleanAccountWriteMeter = metrics.NewRegisteredMeter("state/snapshot/clean/account/write", nil)
+
+ snapshotCleanStorageHitMeter = metrics.NewRegisteredMeter("state/snapshot/clean/storage/hit", nil)
+ snapshotCleanStorageMissMeter = metrics.NewRegisteredMeter("state/snapshot/clean/storage/miss", nil)
+ snapshotCleanStorageInexMeter = metrics.NewRegisteredMeter("state/snapshot/clean/storage/inex", nil)
+ snapshotCleanStorageReadMeter = metrics.NewRegisteredMeter("state/snapshot/clean/storage/read", nil)
+ snapshotCleanStorageWriteMeter = metrics.NewRegisteredMeter("state/snapshot/clean/storage/write", nil)
+
+ snapshotDirtyAccountHitMeter = metrics.NewRegisteredMeter("state/snapshot/dirty/account/hit", nil)
+ snapshotDirtyAccountMissMeter = metrics.NewRegisteredMeter("state/snapshot/dirty/account/miss", nil)
+ snapshotDirtyAccountInexMeter = metrics.NewRegisteredMeter("state/snapshot/dirty/account/inex", nil)
+ snapshotDirtyAccountReadMeter = metrics.NewRegisteredMeter("state/snapshot/dirty/account/read", nil)
+ snapshotDirtyAccountWriteMeter = metrics.NewRegisteredMeter("state/snapshot/dirty/account/write", nil)
+
+ snapshotDirtyStorageHitMeter = metrics.NewRegisteredMeter("state/snapshot/dirty/storage/hit", nil)
+ snapshotDirtyStorageMissMeter = metrics.NewRegisteredMeter("state/snapshot/dirty/storage/miss", nil)
+ snapshotDirtyStorageInexMeter = metrics.NewRegisteredMeter("state/snapshot/dirty/storage/inex", nil)
+ snapshotDirtyStorageReadMeter = metrics.NewRegisteredMeter("state/snapshot/dirty/storage/read", nil)
+ snapshotDirtyStorageWriteMeter = metrics.NewRegisteredMeter("state/snapshot/dirty/storage/write", nil)
+
+ snapshotDirtyAccountHitDepthHist = metrics.NewRegisteredHistogram("state/snapshot/dirty/account/hit/depth", nil, metrics.NewExpDecaySample(1028, 0.015))
+ snapshotDirtyStorageHitDepthHist = metrics.NewRegisteredHistogram("state/snapshot/dirty/storage/hit/depth", nil, metrics.NewExpDecaySample(1028, 0.015))
+
+ snapshotFlushAccountItemMeter = metrics.NewRegisteredMeter("state/snapshot/flush/account/item", nil)
+ snapshotFlushAccountSizeMeter = metrics.NewRegisteredMeter("state/snapshot/flush/account/size", nil)
+ snapshotFlushStorageItemMeter = metrics.NewRegisteredMeter("state/snapshot/flush/storage/item", nil)
+ snapshotFlushStorageSizeMeter = metrics.NewRegisteredMeter("state/snapshot/flush/storage/size", nil)
+
+ snapshotBloomIndexTimer = metrics.NewRegisteredResettingTimer("state/snapshot/bloom/index", nil)
+ snapshotBloomErrorGauge = metrics.NewRegisteredGaugeFloat64("state/snapshot/bloom/error", nil)
+
+ snapshotBloomAccountTrueHitMeter = metrics.NewRegisteredMeter("state/snapshot/bloom/account/truehit", nil)
+ snapshotBloomAccountFalseHitMeter = metrics.NewRegisteredMeter("state/snapshot/bloom/account/falsehit", nil)
+ snapshotBloomAccountMissMeter = metrics.NewRegisteredMeter("state/snapshot/bloom/account/miss", nil)
+
+ snapshotBloomStorageTrueHitMeter = metrics.NewRegisteredMeter("state/snapshot/bloom/storage/truehit", nil)
+ snapshotBloomStorageFalseHitMeter = metrics.NewRegisteredMeter("state/snapshot/bloom/storage/falsehit", nil)
+ snapshotBloomStorageMissMeter = metrics.NewRegisteredMeter("state/snapshot/bloom/storage/miss", nil)
+
+ // ErrSnapshotStale is returned from data accessors if the underlying snapshot
+ // layer had been invalidated due to the chain progressing forward far enough
+ // to not maintain the layer's original state.
+ ErrSnapshotStale = errors.New("snapshot stale")
+
+ // ErrNotCoveredYet is returned from data accessors if the underlying snapshot
+ // is being generated currently and the requested data item is not yet in the
+ // range of accounts covered.
+ ErrNotCoveredYet = errors.New("not covered yet")
+
+ // errSnapshotCycle is returned if a snapshot is attempted to be inserted
+ // that forms a cycle in the snapshot tree.
+ errSnapshotCycle = errors.New("snapshot cycle")
+)
+
+// Snapshot represents the functionality supported by a snapshot storage layer.
+type Snapshot interface {
+ // Root returns the root hash for which this snapshot was made.
+ Root() common.Hash
+
+ // Account directly retrieves the account associated with a particular hash in
+ // the snapshot slim data format.
+ Account(hash common.Hash) (*Account, error)
+
+ // AccountRLP directly retrieves the account RLP associated with a particular
+ // hash in the snapshot slim data format.
+ AccountRLP(hash common.Hash) ([]byte, error)
+
+ // Storage directly retrieves the storage data associated with a particular hash,
+ // within a particular account.
+ Storage(accountHash, storageHash common.Hash) ([]byte, error)
+}
+
+// snapshot is the internal version of the snapshot data layer that supports some
+// additional methods compared to the public API.
+type snapshot interface {
+ Snapshot
+
+ // Parent returns the subsequent layer of a snapshot, or nil if the base was
+ // reached.
+ //
+ // Note, the method is an internal helper to avoid type switching between the
+ // disk and diff layers. There is no locking involved.
+ Parent() snapshot
+
+ // Update creates a new layer on top of the existing snapshot diff tree with
+ // the specified data items.
+ //
+ // Note, the maps are retained by the method to avoid copying everything.
+ Update(blockRoot common.Hash, destructs map[common.Hash]struct{}, accounts map[common.Hash][]byte, storage map[common.Hash]map[common.Hash][]byte) *diffLayer
+
+ // Journal commits an entire diff hierarchy to disk into a single journal entry.
+ // This is meant to be used during shutdown to persist the snapshot without
+ // flattening everything down (bad for reorgs).
+ Journal(buffer *bytes.Buffer) (common.Hash, error)
+
+ // Stale return whether this layer has become stale (was flattened across) or
+ // if it's still live.
+ Stale() bool
+
+ // AccountIterator creates an account iterator over an arbitrary layer.
+ AccountIterator(seek common.Hash) AccountIterator
+
+ // StorageIterator creates a storage iterator over an arbitrary layer.
+ StorageIterator(account common.Hash, seek common.Hash) (StorageIterator, bool)
+}
+
+// SnapshotTree is an Ethereum state snapshot tree. It consists of one persistent
+// base layer backed by a key-value store, on top of which arbitrarily many in-
+// memory diff layers are topped. The memory diffs can form a tree with branching,
+// but the disk layer is singleton and common to all. If a reorg goes deeper than
+// the disk layer, everything needs to be deleted.
+//
+// The goal of a state snapshot is twofold: to allow direct access to account and
+// storage data to avoid expensive multi-level trie lookups; and to allow sorted,
+// cheap iteration of the account/storage tries for sync aid.
+type Tree struct {
+ diskdb ethdb.KeyValueStore // Persistent database to store the snapshot
+ triedb *trie.Database // In-memory cache to access the trie through
+ cache int // Megabytes permitted to use for read caches
+ layers map[common.Hash]snapshot // Collection of all known layers
+ lock sync.RWMutex
+}
+
+// New attempts to load an already existing snapshot from a persistent key-value
+// store (with a number of memory layers from a journal), ensuring that the head
+// of the snapshot matches the expected one.
+//
+// If the snapshot is missing or inconsistent, the entirety is deleted and will
+// be reconstructed from scratch based on the tries in the key-value store, on a
+// background thread.
+func New(diskdb ethdb.KeyValueStore, triedb *trie.Database, cache int, root common.Hash, async bool) *Tree {
+ // Create a new, empty snapshot tree
+ snap := &Tree{
+ diskdb: diskdb,
+ triedb: triedb,
+ cache: cache,
+ layers: make(map[common.Hash]snapshot),
+ }
+ if !async {
+ defer snap.waitBuild()
+ }
+ // Attempt to load a previously persisted snapshot and rebuild one if failed
+ head, err := loadSnapshot(diskdb, triedb, cache, root)
+ if err != nil {
+ log.Warn("Failed to load snapshot, regenerating", "err", err)
+ snap.Rebuild(root)
+ return snap
+ }
+ // Existing snapshot loaded, seed all the layers
+ for head != nil {
+ snap.layers[head.Root()] = head
+ head = head.Parent()
+ }
+ return snap
+}
+
+// waitBuild blocks until the snapshot finishes rebuilding. This method is meant
+// to be used by tests to ensure we're testing what we believe we are.
+func (t *Tree) waitBuild() {
+ // Find the rebuild termination channel
+ var done chan struct{}
+
+ t.lock.RLock()
+ for _, layer := range t.layers {
+ if layer, ok := layer.(*diskLayer); ok {
+ done = layer.genPending
+ break
+ }
+ }
+ t.lock.RUnlock()
+
+ // Wait until the snapshot is generated
+ if done != nil {
+ <-done
+ }
+}
+
+// Snapshot retrieves a snapshot belonging to the given block root, or nil if no
+// snapshot is maintained for that block.
+func (t *Tree) Snapshot(blockRoot common.Hash) Snapshot {
+ t.lock.RLock()
+ defer t.lock.RUnlock()
+
+ return t.layers[blockRoot]
+}
+
+// Update adds a new snapshot into the tree, if that can be linked to an existing
+// old parent. It is disallowed to insert a disk layer (the origin of all).
+func (t *Tree) Update(blockRoot common.Hash, parentRoot common.Hash, destructs map[common.Hash]struct{}, accounts map[common.Hash][]byte, storage map[common.Hash]map[common.Hash][]byte) error {
+ // Reject noop updates to avoid self-loops in the snapshot tree. This is a
+ // special case that can only happen for Clique networks where empty blocks
+ // don't modify the state (0 block subsidy).
+ //
+ // Although we could silently ignore this internally, it should be the caller's
+ // responsibility to avoid even attempting to insert such a snapshot.
+ if blockRoot == parentRoot {
+ return errSnapshotCycle
+ }
+ // Generate a new snapshot on top of the parent
+ parent := t.Snapshot(parentRoot).(snapshot)
+ if parent == nil {
+ return fmt.Errorf("parent [%#x] snapshot missing", parentRoot)
+ }
+ snap := parent.Update(blockRoot, destructs, accounts, storage)
+
+ // Save the new snapshot for later
+ t.lock.Lock()
+ defer t.lock.Unlock()
+
+ t.layers[snap.root] = snap
+ return nil
+}
+
+// Cap traverses downwards the snapshot tree from a head block hash until the
+// number of allowed layers are crossed. All layers beyond the permitted number
+// are flattened downwards.
+func (t *Tree) Cap(root common.Hash, layers int) error {
+ // Retrieve the head snapshot to cap from
+ snap := t.Snapshot(root)
+ if snap == nil {
+ return fmt.Errorf("snapshot [%#x] missing", root)
+ }
+ diff, ok := snap.(*diffLayer)
+ if !ok {
+ return fmt.Errorf("snapshot [%#x] is disk layer", root)
+ }
+ // If the generator is still running, use a more aggressive cap
+ diff.origin.lock.RLock()
+ if diff.origin.genMarker != nil && layers > 8 {
+ layers = 8
+ }
+ diff.origin.lock.RUnlock()
+
+ // Run the internal capping and discard all stale layers
+ t.lock.Lock()
+ defer t.lock.Unlock()
+
+ // Flattening the bottom-most diff layer requires special casing since there's
+ // no child to rewire to the grandparent. In that case we can fake a temporary
+ // child for the capping and then remove it.
+ var persisted *diskLayer
+
+ switch layers {
+ case 0:
+ // If full commit was requested, flatten the diffs and merge onto disk
+ diff.lock.RLock()
+ base := diffToDisk(diff.flatten().(*diffLayer))
+ diff.lock.RUnlock()
+
+ // Replace the entire snapshot tree with the flat base
+ t.layers = map[common.Hash]snapshot{base.root: base}
+ return nil
+
+ case 1:
+ // If full flattening was requested, flatten the diffs but only merge if the
+ // memory limit was reached
+ var (
+ bottom *diffLayer
+ base *diskLayer
+ )
+ diff.lock.RLock()
+ bottom = diff.flatten().(*diffLayer)
+ if bottom.memory >= aggregatorMemoryLimit {
+ base = diffToDisk(bottom)
+ }
+ diff.lock.RUnlock()
+
+ // If all diff layers were removed, replace the entire snapshot tree
+ if base != nil {
+ t.layers = map[common.Hash]snapshot{base.root: base}
+ return nil
+ }
+ // Merge the new aggregated layer into the snapshot tree, clean stales below
+ t.layers[bottom.root] = bottom
+
+ default:
+ // Many layers requested to be retained, cap normally
+ persisted = t.cap(diff, layers)
+ }
+ // Remove any layer that is stale or links into a stale layer
+ children := make(map[common.Hash][]common.Hash)
+ for root, snap := range t.layers {
+ if diff, ok := snap.(*diffLayer); ok {
+ parent := diff.parent.Root()
+ children[parent] = append(children[parent], root)
+ }
+ }
+ var remove func(root common.Hash)
+ remove = func(root common.Hash) {
+ delete(t.layers, root)
+ for _, child := range children[root] {
+ remove(child)
+ }
+ delete(children, root)
+ }
+ for root, snap := range t.layers {
+ if snap.Stale() {
+ remove(root)
+ }
+ }
+ // If the disk layer was modified, regenerate all the cumulative blooms
+ if persisted != nil {
+ var rebloom func(root common.Hash)
+ rebloom = func(root common.Hash) {
+ if diff, ok := t.layers[root].(*diffLayer); ok {
+ diff.rebloom(persisted)
+ }
+ for _, child := range children[root] {
+ rebloom(child)
+ }
+ }
+ rebloom(persisted.root)
+ }
+ return nil
+}
+
+// cap traverses downwards the diff tree until the number of allowed layers are
+// crossed. All diffs beyond the permitted number are flattened downwards. If the
+// layer limit is reached, memory cap is also enforced (but not before).
+//
+// The method returns the new disk layer if diffs were persistend into it.
+func (t *Tree) cap(diff *diffLayer, layers int) *diskLayer {
+ // Dive until we run out of layers or reach the persistent database
+ for ; layers > 2; layers-- {
+ // If we still have diff layers below, continue down
+ if parent, ok := diff.parent.(*diffLayer); ok {
+ diff = parent
+ } else {
+ // Diff stack too shallow, return without modifications
+ return nil
+ }
+ }
+ // We're out of layers, flatten anything below, stopping if it's the disk or if
+ // the memory limit is not yet exceeded.
+ switch parent := diff.parent.(type) {
+ case *diskLayer:
+ return nil
+
+ case *diffLayer:
+ // Flatten the parent into the grandparent. The flattening internally obtains a
+ // write lock on grandparent.
+ flattened := parent.flatten().(*diffLayer)
+ t.layers[flattened.root] = flattened
+
+ diff.lock.Lock()
+ defer diff.lock.Unlock()
+
+ diff.parent = flattened
+ if flattened.memory < aggregatorMemoryLimit {
+ // Accumulator layer is smaller than the limit, so we can abort, unless
+ // there's a snapshot being generated currently. In that case, the trie
+ // will move fron underneath the generator so we **must** merge all the
+ // partial data down into the snapshot and restart the generation.
+ if flattened.parent.(*diskLayer).genAbort == nil {
+ return nil
+ }
+ }
+ default:
+ panic(fmt.Sprintf("unknown data layer: %T", parent))
+ }
+ // If the bottom-most layer is larger than our memory cap, persist to disk
+ bottom := diff.parent.(*diffLayer)
+
+ bottom.lock.RLock()
+ base := diffToDisk(bottom)
+ bottom.lock.RUnlock()
+
+ t.layers[base.root] = base
+ diff.parent = base
+ return base
+}
+
+// diffToDisk merges a bottom-most diff into the persistent disk layer underneath
+// it. The method will panic if called onto a non-bottom-most diff layer.
+func diffToDisk(bottom *diffLayer) *diskLayer {
+ var (
+ base = bottom.parent.(*diskLayer)
+ batch = base.diskdb.NewBatch()
+ stats *generatorStats
+ )
+ // If the disk layer is running a snapshot generator, abort it
+ if base.genAbort != nil {
+ abort := make(chan *generatorStats)
+ base.genAbort <- abort
+ stats = <-abort
+ }
+ // Start by temporarily deleting the current snapshot block marker. This
+ // ensures that in the case of a crash, the entire snapshot is invalidated.
+ rawdb.DeleteSnapshotRoot(batch)
+
+ // Mark the original base as stale as we're going to create a new wrapper
+ base.lock.Lock()
+ if base.stale {
+ panic("parent disk layer is stale") // we've committed into the same base from two children, boo
+ }
+ base.stale = true
+ base.lock.Unlock()
+
+ // Destroy all the destructed accounts from the database
+ for hash := range bottom.destructSet {
+ // Skip any account not covered yet by the snapshot
+ if base.genMarker != nil && bytes.Compare(hash[:], base.genMarker) > 0 {
+ continue
+ }
+ // Remove all storage slots
+ rawdb.DeleteAccountSnapshot(batch, hash)
+ base.cache.Set(hash[:], nil)
+
+ it := rawdb.IterateStorageSnapshots(base.diskdb, hash)
+ for it.Next() {
+ if key := it.Key(); len(key) == 65 { // TODO(karalabe): Yuck, we should move this into the iterator
+ batch.Delete(key)
+ base.cache.Del(key[1:])
+
+ snapshotFlushStorageItemMeter.Mark(1)
+ }
+ }
+ it.Release()
+ }
+ // Push all updated accounts into the database
+ for hash, data := range bottom.accountData {
+ // Skip any account not covered yet by the snapshot
+ if base.genMarker != nil && bytes.Compare(hash[:], base.genMarker) > 0 {
+ continue
+ }
+ // Push the account to disk
+ rawdb.WriteAccountSnapshot(batch, hash, data)
+ base.cache.Set(hash[:], data)
+ snapshotCleanAccountWriteMeter.Mark(int64(len(data)))
+
+ if batch.ValueSize() > ethdb.IdealBatchSize {
+ if err := batch.Write(); err != nil {
+ log.Crit("Failed to write account snapshot", "err", err)
+ }
+ batch.Reset()
+ }
+ snapshotFlushAccountItemMeter.Mark(1)
+ snapshotFlushAccountSizeMeter.Mark(int64(len(data)))
+ }
+ // Push all the storage slots into the database
+ for accountHash, storage := range bottom.storageData {
+ // Skip any account not covered yet by the snapshot
+ if base.genMarker != nil && bytes.Compare(accountHash[:], base.genMarker) > 0 {
+ continue
+ }
+ // Generation might be mid-account, track that case too
+ midAccount := base.genMarker != nil && bytes.Equal(accountHash[:], base.genMarker[:common.HashLength])
+
+ for storageHash, data := range storage {
+ // Skip any slot not covered yet by the snapshot
+ if midAccount && bytes.Compare(storageHash[:], base.genMarker[common.HashLength:]) > 0 {
+ continue
+ }
+ if len(data) > 0 {
+ rawdb.WriteStorageSnapshot(batch, accountHash, storageHash, data)
+ base.cache.Set(append(accountHash[:], storageHash[:]...), data)
+ snapshotCleanStorageWriteMeter.Mark(int64(len(data)))
+ } else {
+ rawdb.DeleteStorageSnapshot(batch, accountHash, storageHash)
+ base.cache.Set(append(accountHash[:], storageHash[:]...), nil)
+ }
+ snapshotFlushStorageItemMeter.Mark(1)
+ snapshotFlushStorageSizeMeter.Mark(int64(len(data)))
+ }
+ if batch.ValueSize() > ethdb.IdealBatchSize {
+ if err := batch.Write(); err != nil {
+ log.Crit("Failed to write storage snapshot", "err", err)
+ }
+ batch.Reset()
+ }
+ }
+ // Update the snapshot block marker and write any remainder data
+ rawdb.WriteSnapshotRoot(batch, bottom.root)
+ if err := batch.Write(); err != nil {
+ log.Crit("Failed to write leftover snapshot", "err", err)
+ }
+ res := &diskLayer{
+ root: bottom.root,
+ cache: base.cache,
+ diskdb: base.diskdb,
+ triedb: base.triedb,
+ genMarker: base.genMarker,
+ genPending: base.genPending,
+ }
+ // If snapshot generation hasn't finished yet, port over all the starts and
+ // continue where the previous round left off.
+ //
+ // Note, the `base.genAbort` comparison is not used normally, it's checked
+ // to allow the tests to play with the marker without triggering this path.
+ if base.genMarker != nil && base.genAbort != nil {
+ res.genMarker = base.genMarker
+ res.genAbort = make(chan chan *generatorStats)
+ go res.generate(stats)
+ }
+ return res
+}
+
+// Journal commits an entire diff hierarchy to disk into a single journal entry.
+// This is meant to be used during shutdown to persist the snapshot without
+// flattening everything down (bad for reorgs).
+//
+// The method returns the root hash of the base layer that needs to be persisted
+// to disk as a trie too to allow continuing any pending generation op.
+func (t *Tree) Journal(root common.Hash) (common.Hash, error) {
+ // Retrieve the head snapshot to journal from var snap snapshot
+ snap := t.Snapshot(root)
+ if snap == nil {
+ return common.Hash{}, fmt.Errorf("snapshot [%#x] missing", root)
+ }
+ // Run the journaling
+ t.lock.Lock()
+ defer t.lock.Unlock()
+
+ journal := new(bytes.Buffer)
+ base, err := snap.(snapshot).Journal(journal)
+ if err != nil {
+ return common.Hash{}, err
+ }
+ // Store the journal into the database and return
+ rawdb.WriteSnapshotJournal(t.diskdb, journal.Bytes())
+ return base, nil
+}
+
+// Rebuild wipes all available snapshot data from the persistent database and
+// discard all caches and diff layers. Afterwards, it starts a new snapshot
+// generator with the given root hash.
+func (t *Tree) Rebuild(root common.Hash) {
+ t.lock.Lock()
+ defer t.lock.Unlock()
+
+ // Track whether there's a wipe currently running and keep it alive if so
+ var wiper chan struct{}
+
+ // Iterate over and mark all layers stale
+ for _, layer := range t.layers {
+ switch layer := layer.(type) {
+ case *diskLayer:
+ // If the base layer is generating, abort it and save
+ if layer.genAbort != nil {
+ abort := make(chan *generatorStats)
+ layer.genAbort <- abort
+
+ if stats := <-abort; stats != nil {
+ wiper = stats.wiping
+ }
+ }
+ // Layer should be inactive now, mark it as stale
+ layer.lock.Lock()
+ layer.stale = true
+ layer.lock.Unlock()
+
+ case *diffLayer:
+ // If the layer is a simple diff, simply mark as stale
+ layer.lock.Lock()
+ atomic.StoreUint32(&layer.stale, 1)
+ layer.lock.Unlock()
+
+ default:
+ panic(fmt.Sprintf("unknown layer type: %T", layer))
+ }
+ }
+ // Start generating a new snapshot from scratch on a backgroung thread. The
+ // generator will run a wiper first if there's not one running right now.
+ log.Info("Rebuilding state snapshot")
+ t.layers = map[common.Hash]snapshot{
+ root: generateSnapshot(t.diskdb, t.triedb, t.cache, root, wiper),
+ }
+}
+
+// AccountIterator creates a new account iterator for the specified root hash and
+// seeks to a starting account hash.
+func (t *Tree) AccountIterator(root common.Hash, seek common.Hash) (AccountIterator, error) {
+ return newFastAccountIterator(t, root, seek)
+}
+
+// StorageIterator creates a new storage iterator for the specified root hash and
+// account. The iterator will be move to the specific start position.
+func (t *Tree) StorageIterator(root common.Hash, account common.Hash, seek common.Hash) (StorageIterator, error) {
+ return newFastStorageIterator(t, root, account, seek)
+}