go-ethereum/core/state/snapshot/snapshot.go
Felix Lange b628d72766
build: upgrade to go 1.19 (#25726)
This changes the CI / release builds to use the latest Go version. It also
upgrades golangci-lint to a newer version compatible with Go 1.19.

In Go 1.19, godoc has gained official support for links and lists. The
syntax for code blocks in doc comments has changed and now requires a
leading tab character. gofmt adapts comments to the new syntax
automatically, so there are a lot of comment re-formatting changes in this
PR. We need to apply the new format in order to pass the CI lint stage with
Go 1.19.

With the linter upgrade, I have decided to disable 'gosec' - it produces
too many false-positive warnings. The 'deadcode' and 'varcheck' linters
have also been removed because golangci-lint warns about them being
unmaintained. 'unused' provides similar coverage and we already have it
enabled, so we don't lose much with this change.
2022-09-10 13:25:40 +02:00

845 lines
30 KiB
Go

// 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/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/core/rawdb"
"github.com/ethereum/go-ethereum/ethdb"
"github.com/ethereum/go-ethereum/log"
"github.com/ethereum/go-ethereum/metrics"
"github.com/ethereum/go-ethereum/rlp"
"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")
// ErrNotConstructed is returned if the callers want to iterate the snapshot
// while the generation is not finished yet.
ErrNotConstructed = errors.New("snapshot is not constructed")
// 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)
}
// Tree 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
// Test hooks
onFlatten func() // Hook invoked when the bottom most diff layers are flattened
}
// 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 the disk layer is broken, the snapshot will be
// reconstructed using both the existing data and the state trie.
// The repair happens on a background thread.
//
// If the memory layers in the journal do not match the disk layer (e.g. there is
// a gap) or the journal is missing, there are two repair cases:
//
// - if the 'recovery' parameter is true, all memory diff-layers will be discarded.
// This case happens when the snapshot is 'ahead' of the state trie.
// - otherwise, the entire snapshot is considered invalid and will be recreated on
// a background thread.
func New(diskdb ethdb.KeyValueStore, triedb *trie.Database, cache int, root common.Hash, async bool, rebuild bool, recovery bool) (*Tree, error) {
// 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, disabled, err := loadSnapshot(diskdb, triedb, cache, root, recovery)
if disabled {
log.Warn("Snapshot maintenance disabled (syncing)")
return snap, nil
}
if err != nil {
if rebuild {
log.Warn("Failed to load snapshot, regenerating", "err", err)
snap.Rebuild(root)
return snap, nil
}
return nil, err // Bail out the error, don't rebuild automatically.
}
// Existing snapshot loaded, seed all the layers
for head != nil {
snap.layers[head.Root()] = head
head = head.Parent()
}
return snap, nil
}
// 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
}
}
// Disable interrupts any pending snapshot generator, deletes all the snapshot
// layers in memory and marks snapshots disabled globally. In order to resume
// the snapshot functionality, the caller must invoke Rebuild.
func (t *Tree) Disable() {
// Interrupt any live snapshot layers
t.lock.Lock()
defer t.lock.Unlock()
for _, layer := range t.layers {
switch layer := layer.(type) {
case *diskLayer:
// If the base layer is generating, abort it
if layer.genAbort != nil {
abort := make(chan *generatorStats)
layer.genAbort <- abort
<-abort
}
// 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))
}
}
t.layers = map[common.Hash]snapshot{}
// Delete all snapshot liveness information from the database
batch := t.diskdb.NewBatch()
rawdb.WriteSnapshotDisabled(batch)
rawdb.DeleteSnapshotRoot(batch)
rawdb.DeleteSnapshotJournal(batch)
rawdb.DeleteSnapshotGenerator(batch)
rawdb.DeleteSnapshotRecoveryNumber(batch)
// Note, we don't delete the sync progress
if err := batch.Write(); err != nil {
log.Crit("Failed to disable snapshots", "err", err)
}
}
// 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]
}
// Snapshots returns all visited layers from the topmost layer with specific
// root and traverses downward. The layer amount is limited by the given number.
// If nodisk is set, then disk layer is excluded.
func (t *Tree) Snapshots(root common.Hash, limits int, nodisk bool) []Snapshot {
t.lock.RLock()
defer t.lock.RUnlock()
if limits == 0 {
return nil
}
layer := t.layers[root]
if layer == nil {
return nil
}
var ret []Snapshot
for {
if _, isdisk := layer.(*diskLayer); isdisk && nodisk {
break
}
ret = append(ret, layer)
limits -= 1
if limits == 0 {
break
}
parent := layer.Parent()
if parent == nil {
break
}
layer = parent
}
return ret
}
// 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)
if parent == nil {
return fmt.Errorf("parent [%#x] snapshot missing", parentRoot)
}
snap := parent.(snapshot).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.
//
// Note, the final diff layer count in general will be one more than the amount
// requested. This happens because the bottom-most diff layer is the accumulator
// which may or may not overflow and cascade to disk. Since this last layer's
// survival is only known *after* capping, we need to omit it from the count if
// we want to ensure that *at least* the requested number of diff layers remain.
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.
if layers == 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
}
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 persisted into it.
//
// Note, the final diff layer count in general will be one more than the amount
// requested. This happens because the bottom-most diff layer is the accumulator
// which may or may not overflow and cascade to disk. Since this last layer's
// survival is only known *after* capping, we need to omit it from the count if
// we want to ensure that *at least* the requested number of diff layers remain.
func (t *Tree) cap(diff *diffLayer, layers int) *diskLayer {
// Dive until we run out of layers or reach the persistent database
for i := 0; i < layers-1; i++ {
// 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:
// Hold the write lock until the flattened parent is linked correctly.
// Otherwise, the stale layer may be accessed by external reads in the
// meantime.
diff.lock.Lock()
defer diff.lock.Unlock()
// Flatten the parent into the grandparent. The flattening internally obtains a
// write lock on grandparent.
flattened := parent.flatten().(*diffLayer)
t.layers[flattened.root] = flattened
// Invoke the hook if it's registered. Ugly hack.
if t.onFlatten != nil {
t.onFlatten()
}
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 from 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.
//
// The disk layer persistence should be operated in an atomic way. All updates should
// be discarded if the whole transition if not finished.
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
}
// Put the deletion in the batch writer, flush all updates in the final step.
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() {
key := it.Key()
batch.Delete(key)
base.cache.Del(key[1:])
snapshotFlushStorageItemMeter.Mark(1)
// Ensure we don't delete too much data blindly (contract can be
// huge). It's ok to flush, the root will go missing in case of a
// crash and we'll detect and regenerate the snapshot.
if batch.ValueSize() > ethdb.IdealBatchSize {
if err := batch.Write(); err != nil {
log.Crit("Failed to write storage deletions", "err", err)
}
batch.Reset()
}
}
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)))
snapshotFlushAccountItemMeter.Mark(1)
snapshotFlushAccountSizeMeter.Mark(int64(len(data)))
// Ensure we don't write too much data blindly. It's ok to flush, the
// root will go missing in case of a crash and we'll detect and regen
// the snapshot.
if batch.ValueSize() > ethdb.IdealBatchSize {
if err := batch.Write(); err != nil {
log.Crit("Failed to write storage deletions", "err", err)
}
batch.Reset()
}
}
// 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)))
}
}
// Update the snapshot block marker and write any remainder data
rawdb.WriteSnapshotRoot(batch, bottom.root)
// Write out the generator progress marker and report
journalProgress(batch, base.genMarker, stats)
// Flush all the updates in the single db operation. Ensure the
// disk layer transition is atomic.
if err := batch.Write(); err != nil {
log.Crit("Failed to write leftover snapshot", "err", err)
}
log.Debug("Journalled disk layer", "root", bottom.root, "complete", base.genMarker == nil)
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()
// Firstly write out the metadata of journal
journal := new(bytes.Buffer)
if err := rlp.Encode(journal, journalVersion); err != nil {
return common.Hash{}, err
}
diskroot := t.diskRoot()
if diskroot == (common.Hash{}) {
return common.Hash{}, errors.New("invalid disk root")
}
// Secondly write out the disk layer root, ensure the
// diff journal is continuous with disk.
if err := rlp.Encode(journal, diskroot); err != nil {
return common.Hash{}, err
}
// Finally write out the journal of each layer in reverse order.
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()
// Firstly delete any recovery flag in the database. Because now we are
// building a brand new snapshot. Also reenable the snapshot feature.
rawdb.DeleteSnapshotRecoveryNumber(t.diskdb)
rawdb.DeleteSnapshotDisabled(t.diskdb)
// 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
<-abort
}
// 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 background 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),
}
}
// 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) {
ok, err := t.generating()
if err != nil {
return nil, err
}
if ok {
return nil, ErrNotConstructed
}
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) {
ok, err := t.generating()
if err != nil {
return nil, err
}
if ok {
return nil, ErrNotConstructed
}
return newFastStorageIterator(t, root, account, seek)
}
// Verify iterates the whole state(all the accounts as well as the corresponding storages)
// with the specific root and compares the re-computed hash with the original one.
func (t *Tree) Verify(root common.Hash) error {
acctIt, err := t.AccountIterator(root, common.Hash{})
if err != nil {
return err
}
defer acctIt.Release()
got, err := generateTrieRoot(nil, acctIt, common.Hash{}, stackTrieGenerate, func(db ethdb.KeyValueWriter, accountHash, codeHash common.Hash, stat *generateStats) (common.Hash, error) {
storageIt, err := t.StorageIterator(root, accountHash, common.Hash{})
if err != nil {
return common.Hash{}, err
}
defer storageIt.Release()
hash, err := generateTrieRoot(nil, storageIt, accountHash, stackTrieGenerate, nil, stat, false)
if err != nil {
return common.Hash{}, err
}
return hash, nil
}, newGenerateStats(), true)
if err != nil {
return err
}
if got != root {
return fmt.Errorf("state root hash mismatch: got %x, want %x", got, root)
}
return nil
}
// disklayer is an internal helper function to return the disk layer.
// The lock of snapTree is assumed to be held already.
func (t *Tree) disklayer() *diskLayer {
var snap snapshot
for _, s := range t.layers {
snap = s
break
}
if snap == nil {
return nil
}
switch layer := snap.(type) {
case *diskLayer:
return layer
case *diffLayer:
return layer.origin
default:
panic(fmt.Sprintf("%T: undefined layer", snap))
}
}
// diskRoot is a internal helper function to return the disk layer root.
// The lock of snapTree is assumed to be held already.
func (t *Tree) diskRoot() common.Hash {
disklayer := t.disklayer()
if disklayer == nil {
return common.Hash{}
}
return disklayer.Root()
}
// generating is an internal helper function which reports whether the snapshot
// is still under the construction.
func (t *Tree) generating() (bool, error) {
t.lock.Lock()
defer t.lock.Unlock()
layer := t.disklayer()
if layer == nil {
return false, errors.New("disk layer is missing")
}
layer.lock.RLock()
defer layer.lock.RUnlock()
return layer.genMarker != nil, nil
}
// diskRoot is a external helper function to return the disk layer root.
func (t *Tree) DiskRoot() common.Hash {
t.lock.Lock()
defer t.lock.Unlock()
return t.diskRoot()
}