triedb/pathdb, core: utilize history reader

core/blockchain_reader.go

@@ -356,6 +356,11 @@ func (bc *BlockChain) StateAt(root common.Hash) (*state.StateDB, error) {
 	return state.New(root, bc.stateDb)
 }
 
+// ArchiveState returns a new mutable archive state.
+func (bc *BlockChain) ArchiveState(root common.Hash) (*state.StateDB, error) {
+	return state.New(root, state.NewArchiveDatabase(bc.stateDb))
+}
+
 // Config retrieves the chain's fork configuration.
 func (bc *BlockChain) Config() *params.ChainConfig { return bc.chainConfig }
 

core/state/database_archive.go

@@ -0,0 +1,124 @@
+// Copyright 2024 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 state
+
+import (
+	"time"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/rlp"
+	"github.com/ethereum/go-ethereum/triedb"
+	"github.com/ethereum/go-ethereum/triedb/pathdb"
+)
+
+// stateReader wraps a pathdb archive reader.
+type archiveReader struct {
+	reader *pathdb.ArchiveReader
+}
+
+// Account implements Reader, retrieving the account specified by the address.
+//
+// An error will be returned if the associated snapshot is already stale or
+// the requested account is not yet covered by the snapshot.
+//
+// The returned account might be nil if it's not existent.
+func (r *archiveReader) Account(addr common.Address) (*types.StateAccount, error) {
+	account, err := r.reader.Account(addr)
+	if err != nil {
+		return nil, err
+	}
+	if account == nil {
+		return nil, nil
+	}
+	acct := &types.StateAccount{
+		Nonce:    account.Nonce,
+		Balance:  account.Balance,
+		CodeHash: account.CodeHash,
+		Root:     common.BytesToHash(account.Root),
+	}
+	if len(acct.CodeHash) == 0 {
+		acct.CodeHash = types.EmptyCodeHash.Bytes()
+	}
+	if acct.Root == (common.Hash{}) {
+		acct.Root = types.EmptyRootHash
+	}
+	return acct, nil
+}
+
+// Storage implements Reader, retrieving the storage slot specified by the
+// address and slot key.
+//
+// An error will be returned if the associated snapshot is already stale or
+// the requested storage slot is not yet covered by the snapshot.
+//
+// The returned storage slot might be empty if it's not existent.
+func (r *archiveReader) Storage(addr common.Address, key common.Hash) (common.Hash, error) {
+	blob, err := r.reader.Storage(addr, key)
+	if err != nil {
+		return common.Hash{}, err
+	}
+	if len(blob) == 0 {
+		return common.Hash{}, nil
+	}
+	_, content, _, err := rlp.Split(blob)
+	if err != nil {
+		return common.Hash{}, err
+	}
+	var slot common.Hash
+	slot.SetBytes(content)
+	return slot, nil
+}
+
+// Stats returns the statistics of the reader, specifically detailing the time
+// spent on account reading and storage reading.
+func (r *archiveReader) Stats() (time.Duration, time.Duration) { return 0, 0 }
+
+// Copy implements Reader, returning a deep-copied archive readerr.
+func (r *archiveReader) Copy() Reader {
+	return &archiveReader{reader: r.reader}
+}
+
+// ArchiveDB is the implementation of Database interface, with the ability to
+// access historical state.
+type ArchiveDB struct {
+	Database
+	triedb *triedb.Database
+}
+
+// NewArchiveDatabase creates an archive database.
+func NewArchiveDatabase(db Database) *ArchiveDB {
+	return &ArchiveDB{
+		Database: db,
+		triedb:   db.TrieDB(),
+	}
+}
+
+// Reader implements Database interface, returning a reader of the specific state.
+func (db *ArchiveDB) Reader(stateRoot common.Hash) (Reader, error) {
+	// Short circuit if the requested state is available in live database
+	r, err := db.Database.Reader(stateRoot)
+	if err == nil {
+		return r, nil
+	}
+	// Construct the archive reader then
+	hr, err := db.triedb.HistoricReader(stateRoot)
+	if err != nil {
+		return nil, err
+	}
+	return &archiveReader{reader: hr}, nil
+}

core/state/statedb.go

@@ -86,9 +86,9 @@ func (m *mutation) isDelete() bool {
 type StateDB struct {
 	db         Database
 	prefetcher *triePrefetcher
-	trie       Trie
 	logger     *tracing.Hooks
 	reader     Reader
+	trie       Trie // trie is only resolved when it's accessed
 
 	// originalRoot is the pre-state root, before any changes were made.
 	// It will be updated when the Commit is called.
@@ -167,17 +167,12 @@ type StateDB struct {
 
 // New creates a new state from a given trie.
 func New(root common.Hash, db Database) (*StateDB, error) {
-	tr, err := db.OpenTrie(root)
-	if err != nil {
-		return nil, err
-	}
 	reader, err := db.Reader(root)
 	if err != nil {
 		return nil, err
 	}
 	return &StateDB{
 		db:                   db,
-		trie:                 tr,
 		originalRoot:         root,
 		reader:               reader,
 		stateObjects:         make(map[common.Address]*stateObject),
@@ -650,7 +645,6 @@ func (s *StateDB) Copy() *StateDB {
 	// Copy all the basic fields, initialize the memory ones
 	state := &StateDB{
 		db:                   s.db,
-		trie:                 mustCopyTrie(s.trie),
 		reader:               s.reader.Copy(),
 		originalRoot:         s.originalRoot,
 		stateObjects:         make(map[common.Address]*stateObject, len(s.stateObjects)),
@@ -676,6 +670,9 @@ func (s *StateDB) Copy() *StateDB {
 		validRevisions:   slices.Clone(s.validRevisions),
 		nextRevisionId:   s.nextRevisionId,
 	}
+	if s.trie != nil {
+		state.trie = mustCopyTrie(s.trie)
+	}
 	if s.witness != nil {
 		state.witness = s.witness.Copy()
 	}
@@ -880,6 +877,14 @@ func (s *StateDB) IntermediateRoot(deleteEmptyObjects bool) common.Hash {
 			s.trie = trie
 		}
 	}
+	if s.trie == nil {
+		tr, err := s.db.OpenTrie(s.originalRoot)
+		if err != nil {
+			s.setError(err)
+			return common.Hash{}
+		}
+		s.trie = tr
+	}
 	// Perform updates before deletions.  This prevents resolution of unnecessary trie nodes
 	// in circumstances similar to the following:
 	//

eth/api_backend.go

@@ -205,7 +205,10 @@ func (b *EthAPIBackend) StateAndHeaderByNumber(ctx context.Context, number rpc.B
 	}
 	stateDb, err := b.eth.BlockChain().StateAt(header.Root)
 	if err != nil {
-		return nil, nil, err
+		stateDb, err = b.eth.BlockChain().ArchiveState(header.Root)
+		if err != nil {
+			return nil, nil, err
+		}
 	}
 	return stateDb, header, nil
 }
@@ -227,7 +230,10 @@ func (b *EthAPIBackend) StateAndHeaderByNumberOrHash(ctx context.Context, blockN
 		}
 		stateDb, err := b.eth.BlockChain().StateAt(header.Root)
 		if err != nil {
-			return nil, nil, err
+			stateDb, err = b.eth.BlockChain().ArchiveState(header.Root)
+			if err != nil {
+				return nil, nil, err
+			}
 		}
 		return stateDb, header, nil
 	}

eth/state_accessor.go

@@ -182,6 +182,10 @@ func (eth *Ethereum) pathState(block *types.Block) (*state.StateDB, func(), erro
 	if err == nil {
 		return statedb, noopReleaser, nil
 	}
+	statedb, err = eth.blockchain.ArchiveState(block.Root())
+	if err == nil {
+		return statedb, noopReleaser, nil
+	}
 	// TODO historic state is not supported in path-based scheme.
 	// Fully archive node in pbss will be implemented by relying
 	// on state history, but needs more work on top.

triedb/database.go

@@ -350,6 +350,15 @@ func (db *Database) StorageIterator(root common.Hash, account common.Hash, seek
 	return pdb.StorageIterator(root, account, seek)
 }
 
+// HistoricReader constructs a reader for accessing the requested historic state.
+func (db *Database) HistoricReader(root common.Hash) (*pathdb.ArchiveReader, error) {
+	pdb, ok := db.backend.(*pathdb.Database)
+	if !ok {
+		return nil, errors.New("not supported")
+	}
+	return pdb.HistoricReader(root)
+}
+
 // IsVerkle returns the indicator if the database is holding a verkle tree.
 func (db *Database) IsVerkle() bool {
 	return db.config.IsVerkle

triedb/pathdb/database.go

@@ -519,6 +519,10 @@ func (db *Database) Close() error {
 	// Release the memory held by clean cache.
 	db.tree.bottom().resetCache()
 
+	// Shutdown background history indexer
+	if db.indexer != nil {
+		db.indexer.close()
+	}
 	// Close the attached state history freezer.
 	if db.freezer == nil {
 		return nil

triedb/pathdb/history_index_reader.go

@@ -300,13 +300,14 @@ func (r *historyReader) resolve(owner common.Address, state common.Hash, id uint
 	return r.resolveStorage(owner, state, id)
 }
 
-func (r *historyReader) read(owner common.Address, state common.Hash, id uint64, latest uint64) ([]byte, error) {
+func (r *historyReader) read(owner common.Address, state common.Hash, targetID uint64, latestID uint64, latestValue []byte) ([]byte, error) {
 	tail, err := r.freezer.Tail()
 	if err != nil {
 		return nil, err
 	}
-	// id == tail is allowed, as the first history object preserved is tail+1
-	if id < tail {
+	// targetID == tail is allowed, as the first history object
+	// available is tail+1
+	if targetID < tail {
 		return nil, errors.New("historic state is pruned")
 	}
 	head := rawdb.ReadStateHistoryIndexHead(r.disk)
@@ -314,7 +315,7 @@ func (r *historyReader) read(owner common.Address, state common.Hash, id uint64,
 	/*
 		the available range of histories is [tail+1, head]
 	*/
-	if head == nil || *head <= id {
+	if head == nil || *head <= targetID {
 		return nil, errors.New("state history is not fully indexed")
 	}
 	ir, ok := r.readers[owner.Hex()+state.Hex()]
@@ -325,15 +326,15 @@ func (r *historyReader) read(owner common.Address, state common.Hash, id uint64,
 		}
 		r.readers[owner.Hex()+state.Hex()] = ir
 	}
-	id, err = ir.readGreaterThan(id)
+	targetID, err = ir.readGreaterThan(targetID)
 	if err != nil {
 		return nil, err
 	}
-	if id == math.MaxUint64 {
-		if *head < latest {
+	if targetID == math.MaxUint64 {
+		if *head < latestID {
 			return nil, errors.New("state history is not fully indexed")
 		}
-		return nil, errors.New("not found")
+		return latestValue, nil
 	}
-	return r.resolve(owner, state, id)
+	return r.resolve(owner, state, targetID)
 }

triedb/pathdb/history_indexer.go

@@ -112,11 +112,15 @@ func (i *historyIndexer) run(done chan struct{}, head uint64, interrupt *atomic.
 		log.Error("Failed to find next state history for indexing", "err", err)
 		return
 	}
-	// TODO what if head is lower than the index head. It can
-	// happen if the entire state history freezer is reset.
-	//if begin > head {
-	//
-	//}
+	// Short circuit if no indexing tasks left
+	if begin == head+1 {
+		return
+	}
+	// Deep reorg occurs, TODO put the reorg logic here
+	if begin > head+1 {
+		log.Error("Deep reorg detected", "head", head, "next", begin)
+		return
+	}
 	log.Info("Start history indexing", "begin", begin, "head", head)
 
 	var (

triedb/pathdb/reader.go

@@ -21,7 +21,9 @@ import (
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/hexutil"
+	"github.com/ethereum/go-ethereum/core/rawdb"
 	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/rlp"
 	"github.com/ethereum/go-ethereum/triedb/database"
@@ -147,3 +149,76 @@ func (db *Database) StateReader(root common.Hash) (database.StateReader, error)
 	}
 	return &reader{layer: layer}, nil
 }
+
+// ArchiveReader is a wrapper over the history reader, providing access to a
+// specific historical state.
+type ArchiveReader struct {
+	db     *Database
+	reader *historyReader
+	id     uint64
+}
+
+// HistoricReader constructs a reader for accessing the requested historic state.
+func (db *Database) HistoricReader(root common.Hash) (*ArchiveReader, error) {
+	id := rawdb.ReadStateID(db.diskdb, root)
+	if id == nil {
+		return nil, fmt.Errorf("state %#x is not available", root)
+	}
+	return &ArchiveReader{
+		id:     *id,
+		db:     db,
+		reader: newHistoryReader(db.diskdb, db.freezer),
+	}, nil
+}
+
+// AccountRLP directly retrieves the account RLP associated with a particular
+// address in the slim data format. An error will be returned if the read
+// operation exits abnormally. Specifically, if the layer is already stale.
+//
+// Note:
+// - the returned account is not a copy, please don't modify it.
+// - no error will be returned if the requested account is not found in database.
+func (r *ArchiveReader) AccountRLP(address common.Address) ([]byte, error) {
+	bottom := r.db.tree.bottom()
+	latest, err := bottom.account(crypto.Keccak256Hash(address.Bytes()), 0)
+	if err != nil {
+		return nil, err
+	}
+	return r.reader.read(address, common.Hash{}, r.id, bottom.stateID(), latest)
+}
+
+// Account directly retrieves the account associated with a particular address in
+// the slim data format. An error will be returned if the read operation exits
+// abnormally. Specifically, if the layer is already stale.
+//
+// No error will be returned if the requested account is not found in database
+func (r *ArchiveReader) Account(address common.Address) (*types.SlimAccount, error) {
+	blob, err := r.AccountRLP(address)
+	if err != nil {
+		return nil, err
+	}
+	if len(blob) == 0 {
+		return nil, nil
+	}
+	account := new(types.SlimAccount)
+	if err := rlp.DecodeBytes(blob, account); err != nil {
+		panic(err)
+	}
+	return account, nil
+}
+
+// Storage directly retrieves the storage data associated with a particular key,
+// within a particular account. An error will be returned if the read operation
+// exits abnormally. Specifically, if the layer is already stale.
+//
+// Note:
+// - the returned storage data is not a copy, please don't modify it.
+// - no error will be returned if the requested slot is not found in database.
+func (r *ArchiveReader) Storage(address common.Address, key common.Hash) ([]byte, error) {
+	bottom := r.db.tree.bottom()
+	latest, err := bottom.storage(crypto.Keccak256Hash(address.Bytes()), crypto.Keccak256Hash(key.Bytes()), 0)
+	if err != nil {
+		return nil, err
+	}
+	return r.reader.read(address, crypto.Keccak256Hash(key.Bytes()), r.id, bottom.stateID(), latest)
+}