[WIP] Dynamic state snapshot

accounts/abi/bind/backends/simulated.go

@@ -119,7 +119,7 @@ func (b *SimulatedBackend) rollback() {
 	statedb, _ := b.blockchain.State()
 
 	b.pendingBlock = blocks[0]
-	b.pendingState, _ = state.New(b.pendingBlock.Root(), statedb.Database())
+	b.pendingState, _ = state.New(b.pendingBlock.Root(), statedb.Database(), nil)
 }
 
 // CodeAt returns the code associated with a certain account in the blockchain.
@@ -347,7 +347,7 @@ func (b *SimulatedBackend) SendTransaction(ctx context.Context, tx *types.Transa
 	statedb, _ := b.blockchain.State()
 
 	b.pendingBlock = blocks[0]
-	b.pendingState, _ = state.New(b.pendingBlock.Root(), statedb.Database())
+	b.pendingState, _ = state.New(b.pendingBlock.Root(), statedb.Database(), nil)
 	return nil
 }
 
@@ -432,7 +432,7 @@ func (b *SimulatedBackend) AdjustTime(adjustment time.Duration) error {
 	statedb, _ := b.blockchain.State()
 
 	b.pendingBlock = blocks[0]
-	b.pendingState, _ = state.New(b.pendingBlock.Root(), statedb.Database())
+	b.pendingState, _ = state.New(b.pendingBlock.Root(), statedb.Database(), nil)
 
 	return nil
 }

cmd/evm/runner.go

@@ -100,10 +100,10 @@ func runCmd(ctx *cli.Context) error {
 		genesisConfig = gen
 		db := rawdb.NewMemoryDatabase()
 		genesis := gen.ToBlock(db)
-		statedb, _ = state.New(genesis.Root(), state.NewDatabase(db))
+		statedb, _ = state.New(genesis.Root(), state.NewDatabase(db), nil)
 		chainConfig = gen.Config
 	} else {
-		statedb, _ = state.New(common.Hash{}, state.NewDatabase(rawdb.NewMemoryDatabase()))
+		statedb, _ = state.New(common.Hash{}, state.NewDatabase(rawdb.NewMemoryDatabase()), nil)
 		genesisConfig = new(core.Genesis)
 	}
 	if ctx.GlobalString(SenderFlag.Name) != "" {

cmd/geth/chaincmd.go

@@ -521,7 +521,7 @@ func dump(ctx *cli.Context) error {
 			fmt.Println("{}")
 			utils.Fatalf("block not found")
 		} else {
-			state, err := state.New(block.Root(), state.NewDatabase(chainDb))
+			state, err := state.New(block.Root(), state.NewDatabase(chainDb), nil)
 			if err != nil {
 				utils.Fatalf("could not create new state: %v", err)
 			}

core/blockchain.go

@@ -33,6 +33,7 @@ import (
 	"github.com/ethereum/go-ethereum/consensus"
 	"github.com/ethereum/go-ethereum/core/rawdb"
 	"github.com/ethereum/go-ethereum/core/state"
+	"github.com/ethereum/go-ethereum/core/state/snapshot"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/core/vm"
 	"github.com/ethereum/go-ethereum/ethdb"
@@ -60,6 +61,10 @@ var (
 	storageUpdateTimer = metrics.NewRegisteredTimer("chain/storage/updates", nil)
 	storageCommitTimer = metrics.NewRegisteredTimer("chain/storage/commits", nil)
 
+	snapshotAccountReadTimer = metrics.NewRegisteredTimer("chain/snapshot/accountreads", nil)
+	snapshotStorageReadTimer = metrics.NewRegisteredTimer("chain/snapshot/storagereads", nil)
+	snapshotCommitTimer      = metrics.NewRegisteredTimer("chain/snapshot/commits", nil)
+
 	blockInsertTimer     = metrics.NewRegisteredTimer("chain/inserts", nil)
 	blockValidationTimer = metrics.NewRegisteredTimer("chain/validation", nil)
 	blockExecutionTimer  = metrics.NewRegisteredTimer("chain/execution", nil)
@@ -134,9 +139,10 @@ type BlockChain struct {
 	chainConfig *params.ChainConfig // Chain & network configuration
 	cacheConfig *CacheConfig        // Cache configuration for pruning
 
-	db     ethdb.Database // Low level persistent database to store final content in
-	triegc *prque.Prque   // Priority queue mapping block numbers to tries to gc
-	gcproc time.Duration  // Accumulates canonical block processing for trie dumping
+	db     ethdb.Database         // Low level persistent database to store final content in
+	snaps  *snapshot.SnapshotTree // Snapshot tree for fast trie leaf access
+	triegc *prque.Prque           // Priority queue mapping block numbers to tries to gc
+	gcproc time.Duration          // Accumulates canonical block processing for trie dumping
 
 	hc            *HeaderChain
 	rmLogsFeed    event.Feed
@@ -286,6 +292,13 @@ func NewBlockChain(db ethdb.Database, cacheConfig *CacheConfig, chainConfig *par
 			}
 		}
 	}
+	// Load any existing snapshot, regenerating it if loading failed
+	head := bc.CurrentBlock()
+	if bc.snaps, err = snapshot.New(bc.db, "snapshot.rlp", head.NumberU64(), head.Root()); err != nil {
+		return nil, err
+	}
+	fmt.Println(bc.snaps)
+
 	// Take ownership of this particular state
 	go bc.update()
 	return bc, nil
@@ -332,7 +345,7 @@ func (bc *BlockChain) loadLastState() error {
 		return bc.Reset()
 	}
 	// Make sure the state associated with the block is available
-	if _, err := state.New(currentBlock.Root(), bc.stateCache); err != nil {
+	if _, err := state.New(currentBlock.Root(), bc.stateCache, bc.snaps); err != nil {
 		// Dangling block without a state associated, init from scratch
 		log.Warn("Head state missing, repairing chain", "number", currentBlock.Number(), "hash", currentBlock.Hash())
 		if err := bc.repair(&currentBlock); err != nil {
@@ -394,7 +407,7 @@ func (bc *BlockChain) SetHead(head uint64) error {
 			if newHeadBlock == nil {
 				newHeadBlock = bc.genesisBlock
 			} else {
-				if _, err := state.New(newHeadBlock.Root(), bc.stateCache); err != nil {
+				if _, err := state.New(newHeadBlock.Root(), bc.stateCache, bc.snaps); err != nil {
 					// Rewound state missing, rolled back to before pivot, reset to genesis
 					newHeadBlock = bc.genesisBlock
 				}
@@ -507,7 +520,7 @@ func (bc *BlockChain) State() (*state.StateDB, error) {
 
 // StateAt returns a new mutable state based on a particular point in time.
 func (bc *BlockChain) StateAt(root common.Hash) (*state.StateDB, error) {
-	return state.New(root, bc.stateCache)
+	return state.New(root, bc.stateCache, bc.snaps)
 }
 
 // StateCache returns the caching database underpinning the blockchain instance.
@@ -558,7 +571,7 @@ func (bc *BlockChain) ResetWithGenesisBlock(genesis *types.Block) error {
 func (bc *BlockChain) repair(head **types.Block) error {
 	for {
 		// Abort if we've rewound to a head block that does have associated state
-		if _, err := state.New((*head).Root(), bc.stateCache); err == nil {
+		if _, err := state.New((*head).Root(), bc.stateCache, bc.snaps); err == nil {
 			log.Info("Rewound blockchain to past state", "number", (*head).Number(), "hash", (*head).Hash())
 			return nil
 		}
@@ -1055,7 +1068,6 @@ func (bc *BlockChain) InsertReceiptChain(blockChain types.Blocks, receiptChain [
 				}
 				// Don't collect too much in-memory, write it out every 100K blocks
 				if len(deleted) > 100000 {
-
 					// Sync the ancient store explicitly to ensure all data has been flushed to disk.
 					if err := bc.db.Sync(); err != nil {
 						return 0, err
@@ -1598,7 +1610,7 @@ func (bc *BlockChain) insertChain(chain types.Blocks, verifySeals bool) (int, []
 		if parent == nil {
 			parent = bc.GetHeader(block.ParentHash(), block.NumberU64()-1)
 		}
-		statedb, err := state.New(parent.Root, bc.stateCache)
+		statedb, err := state.New(parent.Root, bc.stateCache, bc.snaps)
 		if err != nil {
 			return it.index, events, coalescedLogs, err
 		}
@@ -1609,7 +1621,7 @@ func (bc *BlockChain) insertChain(chain types.Blocks, verifySeals bool) (int, []
 		if !bc.cacheConfig.TrieCleanNoPrefetch {
 			if followup, err := it.peek(); followup != nil && err == nil {
 				go func(start time.Time) {
-					throwaway, _ := state.New(parent.Root, bc.stateCache)
+					throwaway, _ := state.New(parent.Root, bc.stateCache, bc.snaps)
 					bc.prefetcher.Prefetch(followup, throwaway, bc.vmConfig, &followupInterrupt)
 
 					blockPrefetchExecuteTimer.Update(time.Since(start))
@@ -1628,14 +1640,16 @@ func (bc *BlockChain) insertChain(chain types.Blocks, verifySeals bool) (int, []
 			return it.index, events, coalescedLogs, err
 		}
 		// Update the metrics touched during block processing
-		accountReadTimer.Update(statedb.AccountReads)     // Account reads are complete, we can mark them
-		storageReadTimer.Update(statedb.StorageReads)     // Storage reads are complete, we can mark them
-		accountUpdateTimer.Update(statedb.AccountUpdates) // Account updates are complete, we can mark them
-		storageUpdateTimer.Update(statedb.StorageUpdates) // Storage updates are complete, we can mark them
+		accountReadTimer.Update(statedb.AccountReads)                 // Account reads are complete, we can mark them
+		storageReadTimer.Update(statedb.StorageReads)                 // Storage reads are complete, we can mark them
+		accountUpdateTimer.Update(statedb.AccountUpdates)             // Account updates are complete, we can mark them
+		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
-		trieproc := statedb.AccountReads + statedb.AccountUpdates
-		trieproc += statedb.StorageReads + statedb.StorageUpdates
+		trieproc := statedb.SnapshotAccountReads + statedb.AccountReads + statedb.AccountUpdates
+		trieproc += statedb.SnapshotStorageReads + statedb.StorageReads + statedb.StorageUpdates
 
 		blockExecutionTimer.Update(time.Since(substart) - trieproc - triehash)
 
@@ -1664,10 +1678,11 @@ func (bc *BlockChain) insertChain(chain types.Blocks, verifySeals bool) (int, []
 		atomic.StoreUint32(&followupInterrupt, 1)
 
 		// Update the metrics touched during block commit
-		accountCommitTimer.Update(statedb.AccountCommits) // Account commits are complete, we can mark them
-		storageCommitTimer.Update(statedb.StorageCommits) // Storage commits are complete, we can mark them
+		accountCommitTimer.Update(statedb.AccountCommits)   // Account commits are complete, we can mark them
+		storageCommitTimer.Update(statedb.StorageCommits)   // Storage commits are complete, we can mark them
+		snapshotCommitTimer.Update(statedb.SnapshotCommits) // Snapshot commits are complete, we can mark them
 
-		blockWriteTimer.Update(time.Since(substart) - statedb.AccountCommits - statedb.StorageCommits)
+		blockWriteTimer.Update(time.Since(substart) - statedb.AccountCommits - statedb.StorageCommits - statedb.SnapshotCommits)
 		blockInsertTimer.UpdateSince(start)
 
 		switch status {

core/chain_makers.go

@@ -228,7 +228,7 @@ func GenerateChain(config *params.ChainConfig, parent *types.Block, engine conse
 		return nil, nil
 	}
 	for i := 0; i < n; i++ {
-		statedb, err := state.New(parent.Root(), state.NewDatabase(db))
+		statedb, err := state.New(parent.Root(), state.NewDatabase(db), nil)
 		if err != nil {
 			panic(err)
 		}

core/genesis.go

@@ -178,7 +178,7 @@ func SetupGenesisBlockWithOverride(db ethdb.Database, genesis *Genesis, override
 	// We have the genesis block in database(perhaps in ancient database)
 	// but the corresponding state is missing.
 	header := rawdb.ReadHeader(db, stored, 0)
-	if _, err := state.New(header.Root, state.NewDatabaseWithCache(db, 0)); err != nil {
+	if _, err := state.New(header.Root, state.NewDatabaseWithCache(db, 0), nil); err != nil {
 		if genesis == nil {
 			genesis = DefaultGenesisBlock()
 		}
@@ -253,7 +253,7 @@ func (g *Genesis) ToBlock(db ethdb.Database) *types.Block {
 	if db == nil {
 		db = rawdb.NewMemoryDatabase()
 	}
-	statedb, _ := state.New(common.Hash{}, state.NewDatabase(db))
+	statedb, _ := state.New(common.Hash{}, state.NewDatabase(db), nil)
 	for addr, account := range g.Alloc {
 		statedb.AddBalance(addr, account.Balance)
 		statedb.SetCode(addr, account.Code)

core/rawdb/accessors_snapshot.go

@@ -0,0 +1,99 @@
+// 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 rawdb
+
+import (
+	"encoding/binary"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/ethdb"
+	"github.com/ethereum/go-ethereum/log"
+)
+
+// ReadSnapshotBlock retrieves the number and root of the block whose state is
+// contained in the persisted snapshot.
+func ReadSnapshotBlock(db ethdb.KeyValueReader) (uint64, common.Hash) {
+	data, _ := db.Get(snapshotBlockKey)
+	if len(data) != 8+common.HashLength {
+		return 0, common.Hash{}
+	}
+	return binary.BigEndian.Uint64(data[:8]), common.BytesToHash(data[8:])
+}
+
+// WriteSnapshotBlock stores the number and root of the block whose state is
+// contained in the persisted snapshot.
+func WriteSnapshotBlock(db ethdb.KeyValueWriter, number uint64, root common.Hash) {
+	if err := db.Put(snapshotBlockKey, append(encodeBlockNumber(number), root.Bytes()...)); err != nil {
+		log.Crit("Failed to store snapsnot block's number and root", "err", err)
+	}
+}
+
+// DeleteSnapshotBlock deletes the number and hash of the block whose state is
+// contained in the persisted snapshot. Since snapshots are not immutable, this
+// method can be used during updates, so a crash or failure will mark the entire
+// snapshot invalid.
+func DeleteSnapshotBlock(db ethdb.KeyValueWriter) {
+	if err := db.Delete(snapshotBlockKey); err != nil {
+		log.Crit("Failed to remove snapsnot block's number and hash", "err", err)
+	}
+}
+
+// ReadAccountSnapshot retrieves the snapshot entry of an account trie leaf.
+func ReadAccountSnapshot(db ethdb.KeyValueReader, hash common.Hash) []byte {
+	data, _ := db.Get(accountSnapshotKey(hash))
+	return data
+}
+
+// WriteAccountSnapshot stores the snapshot entry of an account trie leaf.
+func WriteAccountSnapshot(db ethdb.KeyValueWriter, hash common.Hash, entry []byte) {
+	if err := db.Put(accountSnapshotKey(hash), entry); err != nil {
+		log.Crit("Failed to store account snapshot", "err", err)
+	}
+}
+
+// DeleteAccountSnapshot removes the snapshot entry of an account trie leaf.
+func DeleteAccountSnapshot(db ethdb.KeyValueWriter, hash common.Hash) {
+	if err := db.Delete(accountSnapshotKey(hash)); err != nil {
+		log.Crit("Failed to delete account snapshot", "err", err)
+	}
+}
+
+// ReadStorageSnapshot retrieves the snapshot entry of an storage trie leaf.
+func ReadStorageSnapshot(db ethdb.KeyValueReader, accountHash, storageHash common.Hash) []byte {
+	data, _ := db.Get(storageSnapshotKey(accountHash, storageHash))
+	return data
+}
+
+// WriteStorageSnapshot stores the snapshot entry of an storage trie leaf.
+func WriteStorageSnapshot(db ethdb.KeyValueWriter, accountHash, storageHash common.Hash, entry []byte) {
+	if err := db.Put(storageSnapshotKey(accountHash, storageHash), entry); err != nil {
+		log.Crit("Failed to store storage snapshot", "err", err)
+	}
+}
+
+// DeleteStorageSnapshot removes the snapshot entry of an storage trie leaf.
+func DeleteStorageSnapshot(db ethdb.KeyValueWriter, accountHash, storageHash common.Hash) {
+	if err := db.Delete(storageSnapshotKey(accountHash, storageHash)); err != nil {
+		log.Crit("Failed to delete storage snapshot", "err", err)
+	}
+}
+
+// IterateStorageSnapshots returns an iterator for walking the entire storage
+// space of a specific account.
+func IterateStorageSnapshots(db ethdb.Iteratee, accountHash common.Hash) ethdb.Iterator {
+	return db.NewIteratorWithPrefix(storageSnapshotsKey(accountHash))
+}

core/rawdb/database.go

@@ -240,6 +240,8 @@ func InspectDatabase(db ethdb.Database) error {
 		hashNumPairing  common.StorageSize
 		trieSize        common.StorageSize
 		txlookupSize    common.StorageSize
+		accountSnapSize common.StorageSize
+		storageSnapSize common.StorageSize
 		preimageSize    common.StorageSize
 		bloomBitsSize   common.StorageSize
 		cliqueSnapsSize common.StorageSize
@@ -281,6 +283,10 @@ func InspectDatabase(db ethdb.Database) error {
 			receiptSize += size
 		case bytes.HasPrefix(key, txLookupPrefix) && len(key) == (len(txLookupPrefix)+common.HashLength):
 			txlookupSize += size
+		case bytes.HasPrefix(key, StateSnapshotPrefix) && len(key) == (len(StateSnapshotPrefix)+common.HashLength):
+			accountSnapSize += size
+		case bytes.HasPrefix(key, StateSnapshotPrefix) && len(key) == (len(StateSnapshotPrefix)+2*common.HashLength):
+			storageSnapSize += size
 		case bytes.HasPrefix(key, preimagePrefix) && len(key) == (len(preimagePrefix)+common.HashLength):
 			preimageSize += size
 		case bytes.HasPrefix(key, bloomBitsPrefix) && len(key) == (len(bloomBitsPrefix)+10+common.HashLength):
@@ -332,6 +338,8 @@ func InspectDatabase(db ethdb.Database) error {
 		{"Key-Value store", "Bloombit index", bloomBitsSize.String()},
 		{"Key-Value store", "Trie nodes", trieSize.String()},
 		{"Key-Value store", "Trie preimages", preimageSize.String()},
+		{"Key-Value store", "Account snapshot", accountSnapSize.String()},
+		{"Key-Value store", "Storage snapshot", storageSnapSize.String()},
 		{"Key-Value store", "Clique snapshots", cliqueSnapsSize.String()},
 		{"Key-Value store", "Singleton metadata", metadata.String()},
 		{"Ancient store", "Headers", ancientHeaders.String()},

core/rawdb/schema.go

@@ -41,6 +41,9 @@ var (
 	// fastTrieProgressKey tracks the number of trie entries imported during fast sync.
 	fastTrieProgressKey = []byte("TrieSync")
 
+	// snapshotBlockKey tracks the number and hash of the last snapshot.
+	snapshotBlockKey = []byte("SnapshotBlock")
+
 	// Data item prefixes (use single byte to avoid mixing data types, avoid `i`, used for indexes).
 	headerPrefix       = []byte("h") // headerPrefix + num (uint64 big endian) + hash -> header
 	headerTDSuffix     = []byte("t") // headerPrefix + num (uint64 big endian) + hash + headerTDSuffix -> td
@@ -50,8 +53,9 @@ var (
 	blockBodyPrefix     = []byte("b") // blockBodyPrefix + num (uint64 big endian) + hash -> block body
 	blockReceiptsPrefix = []byte("r") // blockReceiptsPrefix + num (uint64 big endian) + hash -> block receipts
 
-	txLookupPrefix  = []byte("l") // txLookupPrefix + hash -> transaction/receipt lookup metadata
-	bloomBitsPrefix = []byte("B") // bloomBitsPrefix + bit (uint16 big endian) + section (uint64 big endian) + hash -> bloom bits
+	txLookupPrefix      = []byte("l") // txLookupPrefix + hash -> transaction/receipt lookup metadata
+	bloomBitsPrefix     = []byte("B") // bloomBitsPrefix + bit (uint16 big endian) + section (uint64 big endian) + hash -> bloom bits
+	StateSnapshotPrefix = []byte("s") // StateSnapshotPrefix + account hash [+ storage hash] -> account/storage trie value
 
 	preimagePrefix = []byte("secure-key-")      // preimagePrefix + hash -> preimage
 	configPrefix   = []byte("ethereum-config-") // config prefix for the db
@@ -145,6 +149,21 @@ func txLookupKey(hash common.Hash) []byte {
 	return append(txLookupPrefix, hash.Bytes()...)
 }
 
+// accountSnapshotKey = StateSnapshotPrefix + hash
+func accountSnapshotKey(hash common.Hash) []byte {
+	return append(StateSnapshotPrefix, hash.Bytes()...)
+}
+
+// storageSnapshotKey = StateSnapshotPrefix + account hash + storage hash
+func storageSnapshotKey(accountHash, storageHash common.Hash) []byte {
+	return append(append(StateSnapshotPrefix, accountHash.Bytes()...), storageHash.Bytes()...)
+}
+
+// storageSnapshotsKey = StateSnapshotPrefix + account hash + storage hash
+func storageSnapshotsKey(accountHash common.Hash) []byte {
+	return append(StateSnapshotPrefix, accountHash.Bytes()...)
+}
+
 // bloomBitsKey = bloomBitsPrefix + bit (uint16 big endian) + section (uint64 big endian) + hash
 func bloomBitsKey(bit uint, section uint64, hash common.Hash) []byte {
 	key := append(append(bloomBitsPrefix, make([]byte, 10)...), hash.Bytes()...)