plugeth/core/state/snapshot/disklayer.go

167 lines
5.7 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
import (
"bytes"
"sync"
"github.com/VictoriaMetrics/fastcache"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/core/rawdb"
"github.com/ethereum/go-ethereum/ethdb"
"github.com/ethereum/go-ethereum/rlp"
"github.com/ethereum/go-ethereum/trie"
)
// diskLayer is a low level persistent snapshot built on top of a key-value store.
type diskLayer struct {
diskdb ethdb.KeyValueStore // Key-value store containing the base snapshot
triedb *trie.Database // Trie node cache for reconstuction purposes
cache *fastcache.Cache // Cache to avoid hitting the disk for direct access
root common.Hash // Root hash of the base snapshot
stale bool // Signals that the layer became stale (state progressed)
genMarker []byte // Marker for the state that's indexed during initial layer generation
genPending chan struct{} // Notification channel when generation is done (test synchronicity)
genAbort chan chan *generatorStats // Notification channel to abort generating the snapshot in this layer
lock sync.RWMutex
}
// Root returns root hash for which this snapshot was made.
func (dl *diskLayer) Root() common.Hash {
return dl.root
}
// Parent always returns nil as there's no layer below the disk.
func (dl *diskLayer) Parent() snapshot {
return nil
}
// Stale return whether this layer has become stale (was flattened across) or if
// it's still live.
func (dl *diskLayer) Stale() bool {
dl.lock.RLock()
defer dl.lock.RUnlock()
return dl.stale
}
// Account directly retrieves the account associated with a particular hash in
// the snapshot slim data format.
func (dl *diskLayer) Account(hash common.Hash) (*Account, error) {
data, err := dl.AccountRLP(hash)
if err != nil {
return nil, err
}
if len(data) == 0 { // can be both nil and []byte{}
return nil, nil
}
account := new(Account)
if err := rlp.DecodeBytes(data, account); err != nil {
panic(err)
}
return account, nil
}
// AccountRLP directly retrieves the account RLP associated with a particular
// hash in the snapshot slim data format.
func (dl *diskLayer) AccountRLP(hash common.Hash) ([]byte, error) {
dl.lock.RLock()
defer dl.lock.RUnlock()
// If the layer was flattened into, consider it invalid (any live reference to
// the original should be marked as unusable).
if dl.stale {
return nil, ErrSnapshotStale
}
// If the layer is being generated, ensure the requested hash has already been
// covered by the generator.
if dl.genMarker != nil && bytes.Compare(hash[:], dl.genMarker) > 0 {
return nil, ErrNotCoveredYet
}
// If we're in the disk layer, all diff layers missed
snapshotDirtyAccountMissMeter.Mark(1)
// Try to retrieve the account from the memory cache
if blob, found := dl.cache.HasGet(nil, hash[:]); found {
snapshotCleanAccountHitMeter.Mark(1)
snapshotCleanAccountReadMeter.Mark(int64(len(blob)))
return blob, nil
}
// Cache doesn't contain account, pull from disk and cache for later
blob := rawdb.ReadAccountSnapshot(dl.diskdb, hash)
dl.cache.Set(hash[:], blob)
snapshotCleanAccountMissMeter.Mark(1)
if n := len(blob); n > 0 {
snapshotCleanAccountWriteMeter.Mark(int64(n))
} else {
snapshotCleanAccountInexMeter.Mark(1)
}
return blob, nil
}
// Storage directly retrieves the storage data associated with a particular hash,
// within a particular account.
func (dl *diskLayer) Storage(accountHash, storageHash common.Hash) ([]byte, error) {
dl.lock.RLock()
defer dl.lock.RUnlock()
// If the layer was flattened into, consider it invalid (any live reference to
// the original should be marked as unusable).
if dl.stale {
return nil, ErrSnapshotStale
}
key := append(accountHash[:], storageHash[:]...)
// If the layer is being generated, ensure the requested hash has already been
// covered by the generator.
if dl.genMarker != nil && bytes.Compare(key, dl.genMarker) > 0 {
return nil, ErrNotCoveredYet
}
// If we're in the disk layer, all diff layers missed
snapshotDirtyStorageMissMeter.Mark(1)
// Try to retrieve the storage slot from the memory cache
if blob, found := dl.cache.HasGet(nil, key); found {
snapshotCleanStorageHitMeter.Mark(1)
snapshotCleanStorageReadMeter.Mark(int64(len(blob)))
return blob, nil
}
// Cache doesn't contain storage slot, pull from disk and cache for later
blob := rawdb.ReadStorageSnapshot(dl.diskdb, accountHash, storageHash)
dl.cache.Set(key, blob)
snapshotCleanStorageMissMeter.Mark(1)
if n := len(blob); n > 0 {
snapshotCleanStorageWriteMeter.Mark(int64(n))
} else {
snapshotCleanStorageInexMeter.Mark(1)
}
return blob, nil
}
// 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.
func (dl *diskLayer) Update(blockHash common.Hash, destructs map[common.Hash]struct{}, accounts map[common.Hash][]byte, storage map[common.Hash]map[common.Hash][]byte) *diffLayer {
return newDiffLayer(dl, blockHash, destructs, accounts, storage)
}