all: remove database commit callback, rework noderesolver (#26637)

This change ports some changes from the main PBSS PR:

  - get rid of callback function in `trie.Database.Commit` which is not required anymore
  - rework the `nodeResolver` in `trie.Iterator` to make it compatible with multiple state scheme
  - some other shallow changes in tests and typo-fixes

cmd/geth/snapshot.go

@@ -165,6 +165,8 @@ block is used.
 	}
 )
 
+// Deprecation: this command should be deprecated once the hash-based
+// scheme is deprecated.
 func pruneState(ctx *cli.Context) error {
 	stack, config := makeConfigNode(ctx)
 	defer stack.Close()
@@ -433,7 +435,7 @@ func traverseRawState(ctx *cli.Context) error {
 					nodes += 1
 					node := storageIter.Hash()
 
-					// Check the present for non-empty hash node(embedded node doesn't
+					// Check the presence for non-empty hash node(embedded node doesn't
 					// have their own hash).
 					if node != (common.Hash{}) {
 						blob := rawdb.ReadLegacyTrieNode(chaindb, node)

core/blockchain.go

@@ -945,14 +945,14 @@ func (bc *BlockChain) Stop() {
 				recent := bc.GetBlockByNumber(number - offset)
 
 				log.Info("Writing cached state to disk", "block", recent.Number(), "hash", recent.Hash(), "root", recent.Root())
-				if err := triedb.Commit(recent.Root(), true, nil); err != nil {
+				if err := triedb.Commit(recent.Root(), true); err != nil {
 					log.Error("Failed to commit recent state trie", "err", err)
 				}
 			}
 		}
 		if snapBase != (common.Hash{}) {
 			log.Info("Writing snapshot state to disk", "root", snapBase)
-			if err := triedb.Commit(snapBase, true, nil); err != nil {
+			if err := triedb.Commit(snapBase, true); err != nil {
 				log.Error("Failed to commit recent state trie", "err", err)
 			}
 		}
@@ -1343,7 +1343,7 @@ func (bc *BlockChain) writeBlockWithState(block *types.Block, receipts []*types.
 	}
 	// If we're running an archive node, always flush
 	if bc.cacheConfig.TrieDirtyDisabled {
-		return bc.triedb.Commit(root, false, nil)
+		return bc.triedb.Commit(root, false)
 	}
 	// Full but not archive node, do proper garbage collection
 	bc.triedb.Reference(root, common.Hash{}) // metadata reference to keep trie alive
@@ -1379,7 +1379,7 @@ func (bc *BlockChain) writeBlockWithState(block *types.Block, receipts []*types.
 				log.Info("State in memory for too long, committing", "time", bc.gcproc, "allowance", flushInterval, "optimum", float64(chosen-bc.lastWrite)/TriesInMemory)
 			}
 			// Flush an entire trie and restart the counters
-			bc.triedb.Commit(header.Root, true, nil)
+			bc.triedb.Commit(header.Root, true)
 			bc.lastWrite = chosen
 			bc.gcproc = 0
 		}

core/blockchain_repair_test.go

@@ -1803,7 +1803,7 @@ func testRepair(t *testing.T, tt *rewindTest, snapshots bool) {
 		t.Fatalf("Failed to import canonical chain start: %v", err)
 	}
 	if tt.commitBlock > 0 {
-		chain.stateCache.TrieDB().Commit(canonblocks[tt.commitBlock-1].Root(), true, nil)
+		chain.stateCache.TrieDB().Commit(canonblocks[tt.commitBlock-1].Root(), false)
 		if snapshots {
 			if err := chain.snaps.Cap(canonblocks[tt.commitBlock-1].Root(), 0); err != nil {
 				t.Fatalf("Failed to flatten snapshots: %v", err)
@@ -1918,7 +1918,7 @@ func TestIssue23496(t *testing.T) {
 	if _, err := chain.InsertChain(blocks[:1]); err != nil {
 		t.Fatalf("Failed to import canonical chain start: %v", err)
 	}
-	chain.stateCache.TrieDB().Commit(blocks[0].Root(), true, nil)
+	chain.stateCache.TrieDB().Commit(blocks[0].Root(), false)
 
 	// Insert block B2 and commit the snapshot into disk
 	if _, err := chain.InsertChain(blocks[1:2]); err != nil {
@@ -1932,7 +1932,7 @@ func TestIssue23496(t *testing.T) {
 	if _, err := chain.InsertChain(blocks[2:3]); err != nil {
 		t.Fatalf("Failed to import canonical chain start: %v", err)
 	}
-	chain.stateCache.TrieDB().Commit(blocks[2].Root(), true, nil)
+	chain.stateCache.TrieDB().Commit(blocks[2].Root(), false)
 
 	// Insert the remaining blocks
 	if _, err := chain.InsertChain(blocks[3:]); err != nil {

core/blockchain_sethead_test.go

@@ -2004,7 +2004,7 @@ func testSetHead(t *testing.T, tt *rewindTest, snapshots bool) {
 		t.Fatalf("Failed to import canonical chain start: %v", err)
 	}
 	if tt.commitBlock > 0 {
-		chain.stateCache.TrieDB().Commit(canonblocks[tt.commitBlock-1].Root(), true, nil)
+		chain.stateCache.TrieDB().Commit(canonblocks[tt.commitBlock-1].Root(), false)
 		if snapshots {
 			if err := chain.snaps.Cap(canonblocks[tt.commitBlock-1].Root(), 0); err != nil {
 				t.Fatalf("Failed to flatten snapshots: %v", err)

core/blockchain_snapshot_test.go

@@ -99,7 +99,7 @@ func (basic *snapshotTestBasic) prepare(t *testing.T) (*BlockChain, []*types.Blo
 		startPoint = point
 
 		if basic.commitBlock > 0 && basic.commitBlock == point {
-			chain.stateCache.TrieDB().Commit(blocks[point-1].Root(), true, nil)
+			chain.stateCache.TrieDB().Commit(blocks[point-1].Root(), false)
 		}
 		if basic.snapshotBlock > 0 && basic.snapshotBlock == point {
 			// Flushing the entire snap tree into the disk, the

core/chain_makers.go

@@ -312,7 +312,7 @@ func GenerateChain(config *params.ChainConfig, parent *types.Block, engine conse
 			if err != nil {
 				panic(fmt.Sprintf("state write error: %v", err))
 			}
-			if err := statedb.Database().TrieDB().Commit(root, false, nil); err != nil {
+			if err := statedb.Database().TrieDB().Commit(root, false); err != nil {
 				panic(fmt.Sprintf("trie write error: %v", err))
 			}
 			return block, b.receipts

core/dao_test.go

@@ -83,7 +83,7 @@ func TestDAOForkRangeExtradata(t *testing.T) {
 		if _, err := bc.InsertChain(blocks); err != nil {
 			t.Fatalf("failed to import contra-fork chain for expansion: %v", err)
 		}
-		if err := bc.stateCache.TrieDB().Commit(bc.CurrentHeader().Root, true, nil); err != nil {
+		if err := bc.stateCache.TrieDB().Commit(bc.CurrentHeader().Root, false); err != nil {
 			t.Fatalf("failed to commit contra-fork head for expansion: %v", err)
 		}
 		bc.Stop()
@@ -106,7 +106,7 @@ func TestDAOForkRangeExtradata(t *testing.T) {
 		if _, err := bc.InsertChain(blocks); err != nil {
 			t.Fatalf("failed to import pro-fork chain for expansion: %v", err)
 		}
-		if err := bc.stateCache.TrieDB().Commit(bc.CurrentHeader().Root, true, nil); err != nil {
+		if err := bc.stateCache.TrieDB().Commit(bc.CurrentHeader().Root, false); err != nil {
 			t.Fatalf("failed to commit pro-fork head for expansion: %v", err)
 		}
 		bc.Stop()
@@ -131,7 +131,7 @@ func TestDAOForkRangeExtradata(t *testing.T) {
 	if _, err := bc.InsertChain(blocks); err != nil {
 		t.Fatalf("failed to import contra-fork chain for expansion: %v", err)
 	}
-	if err := bc.stateCache.TrieDB().Commit(bc.CurrentHeader().Root, true, nil); err != nil {
+	if err := bc.stateCache.TrieDB().Commit(bc.CurrentHeader().Root, false); err != nil {
 		t.Fatalf("failed to commit contra-fork head for expansion: %v", err)
 	}
 	blocks, _ = GenerateChain(&proConf, conBc.CurrentBlock(), ethash.NewFaker(), genDb, 1, func(i int, gen *BlockGen) {})
@@ -149,7 +149,7 @@ func TestDAOForkRangeExtradata(t *testing.T) {
 	if _, err := bc.InsertChain(blocks); err != nil {
 		t.Fatalf("failed to import pro-fork chain for expansion: %v", err)
 	}
-	if err := bc.stateCache.TrieDB().Commit(bc.CurrentHeader().Root, true, nil); err != nil {
+	if err := bc.stateCache.TrieDB().Commit(bc.CurrentHeader().Root, false); err != nil {
 		t.Fatalf("failed to commit pro-fork head for expansion: %v", err)
 	}
 	blocks, _ = GenerateChain(&conConf, proBc.CurrentBlock(), ethash.NewFaker(), genDb, 1, func(i int, gen *BlockGen) {})

core/genesis.go

@@ -157,7 +157,7 @@ func (ga *GenesisAlloc) flush(db ethdb.Database, triedb *trie.Database) error {
 	}
 	// Commit newly generated states into disk if it's not empty.
 	if root != types.EmptyRootHash {
-		if err := triedb.Commit(root, true, nil); err != nil {
+		if err := triedb.Commit(root, true); err != nil {
 			return err
 		}
 	}

core/state/iterator_test.go

@@ -17,17 +17,17 @@
 package state
 
 import (
-	"bytes"
 	"testing"
 
 	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/rawdb"
 )
 
 // Tests that the node iterator indeed walks over the entire database contents.
 func TestNodeIteratorCoverage(t *testing.T) {
 	// Create some arbitrary test state to iterate
 	db, sdb, root, _ := makeTestState()
-	sdb.TrieDB().Commit(root, false, nil)
+	sdb.TrieDB().Commit(root, false)
 
 	state, err := New(root, sdb, nil)
 	if err != nil {
@@ -40,29 +40,54 @@ func TestNodeIteratorCoverage(t *testing.T) {
 			hashes[it.Hash] = struct{}{}
 		}
 	}
-	// Cross check the iterated hashes and the database/nodepool content
-	for hash := range hashes {
-		if _, err = sdb.TrieDB().Node(hash); err != nil {
-			_, err = sdb.ContractCode(common.Hash{}, hash)
-		}
-		if err != nil {
-			t.Errorf("failed to retrieve reported node %x", hash)
-		}
-	}
-	for _, hash := range sdb.TrieDB().Nodes() {
-		if _, ok := hashes[hash]; !ok {
-			t.Errorf("state entry not reported %x", hash)
+	// Check in-disk nodes
+	var (
+		seenNodes = make(map[common.Hash]struct{})
+		seenCodes = make(map[common.Hash]struct{})
+	)
+	it := db.NewIterator(nil, nil)
+	for it.Next() {
+		ok, hash := isTrieNode(sdb.TrieDB().Scheme(), it.Key(), it.Value())
+		if !ok {
+			continue
 		}
+		seenNodes[hash] = struct{}{}
 	}
-	it := db.NewIterator(nil, nil)
+	it.Release()
+
+	// Check in-disk codes
+	it = db.NewIterator(nil, nil)
 	for it.Next() {
-		key := it.Key()
-		if bytes.HasPrefix(key, []byte("secure-key-")) {
+		ok, hash := rawdb.IsCodeKey(it.Key())
+		if !ok {
 			continue
 		}
-		if _, ok := hashes[common.BytesToHash(key)]; !ok {
-			t.Errorf("state entry not reported %x", key)
+		if _, ok := hashes[common.BytesToHash(hash)]; !ok {
+			t.Errorf("state entry not reported %x", it.Key())
 		}
+		seenCodes[common.BytesToHash(hash)] = struct{}{}
 	}
 	it.Release()
+
+	// Cross check the iterated hashes and the database/nodepool content
+	for hash := range hashes {
+		_, ok := seenNodes[hash]
+		if !ok {
+			_, ok = seenCodes[hash]
+		}
+		if !ok {
+			t.Errorf("failed to retrieve reported node %x", hash)
+		}
+	}
+}
+
+// isTrieNode is a helper function which reports if the provided
+// database entry belongs to a trie node or not.
+func isTrieNode(scheme string, key, val []byte) (bool, common.Hash) {
+	if scheme == rawdb.HashScheme {
+		if len(key) == common.HashLength {
+			return true, common.BytesToHash(key)
+		}
+	}
+	return false, common.Hash{}
 }

core/state/pruner/pruner.go

@@ -363,7 +363,7 @@ func RecoverPruning(datadir string, db ethdb.Database, trieCachePath string) err
 	}
 	headBlock := rawdb.ReadHeadBlock(db)
 	if headBlock == nil {
-		return errors.New("Failed to load head block")
+		return errors.New("failed to load head block")
 	}
 	// Initialize the snapshot tree in recovery mode to handle this special case:
 	// - Users run the `prune-state` command multiple times

core/state/snapshot/generate.go

@@ -359,19 +359,22 @@ func (dl *diskLayer) generateRange(ctx *generatorContext, trieId *trie.ID, prefi
 	}
 	// We use the snap data to build up a cache which can be used by the
 	// main account trie as a primary lookup when resolving hashes
-	var snapNodeCache ethdb.Database
+	var resolver trie.NodeResolver
 	if len(result.keys) > 0 {
-		snapNodeCache = rawdb.NewMemoryDatabase()
-		snapTrieDb := trie.NewDatabase(snapNodeCache)
-		snapTrie := trie.NewEmpty(snapTrieDb)
+		mdb := rawdb.NewMemoryDatabase()
+		tdb := trie.NewDatabase(mdb)
+		snapTrie := trie.NewEmpty(tdb)
 		for i, key := range result.keys {
 			snapTrie.Update(key, result.vals[i])
 		}
-		root, nodes, _ := snapTrie.Commit(false)
-		if nodes != nil {
-			snapTrieDb.Update(trie.NewWithNodeSet(nodes))
+		root, nodes, err := snapTrie.Commit(false)
+		if err == nil && nodes != nil {
+			tdb.Update(trie.NewWithNodeSet(nodes))
+			tdb.Commit(root, false)
+		}
+		resolver = func(owner common.Hash, path []byte, hash common.Hash) []byte {
+			return rawdb.ReadTrieNode(mdb, owner, path, hash, tdb.Scheme())
 		}
-		snapTrieDb.Commit(root, false, nil)
 	}
 	// Construct the trie for state iteration, reuse the trie
 	// if it's already opened with some nodes resolved.
@@ -400,7 +403,7 @@ func (dl *diskLayer) generateRange(ctx *generatorContext, trieId *trie.ID, prefi
 		start    = time.Now()
 		internal time.Duration
 	)
-	nodeIt.AddResolver(snapNodeCache)
+	nodeIt.AddResolver(resolver)
 
 	for iter.Next() {
 		if last != nil && bytes.Compare(iter.Key, last) > 0 {

core/state/snapshot/generate_test.go

@@ -203,7 +203,7 @@ func (t *testHelper) Commit() common.Hash {
 		t.nodes.Merge(nodes)
 	}
 	t.triedb.Update(t.nodes)
-	t.triedb.Commit(root, false, nil)
+	t.triedb.Commit(root, false)
 	return root
 }
 
@@ -391,7 +391,7 @@ func TestGenerateCorruptAccountTrie(t *testing.T) {
 	root := helper.Commit() // Root: 0xa04693ea110a31037fb5ee814308a6f1d76bdab0b11676bdf4541d2de55ba978
 
 	// Delete an account trie leaf and ensure the generator chokes
-	helper.triedb.Commit(root, false, nil)
+	helper.triedb.Commit(root, false)
 	helper.diskdb.Delete(common.HexToHash("0x65145f923027566669a1ae5ccac66f945b55ff6eaeb17d2ea8e048b7d381f2d7").Bytes())
 
 	snap := generateSnapshot(helper.diskdb, helper.triedb, 16, root)

core/state/statedb_test.go

@@ -55,7 +55,7 @@ func TestUpdateLeaks(t *testing.T) {
 	}
 
 	root := state.IntermediateRoot(false)
-	if err := state.Database().TrieDB().Commit(root, false, nil); err != nil {
+	if err := state.Database().TrieDB().Commit(root, false); err != nil {
 		t.Errorf("can not commit trie %v to persistent database", root.Hex())
 	}
 
@@ -106,7 +106,7 @@ func TestIntermediateLeaks(t *testing.T) {
 	if err != nil {
 		t.Fatalf("failed to commit transition state: %v", err)
 	}
-	if err = transState.Database().TrieDB().Commit(transRoot, false, nil); err != nil {
+	if err = transState.Database().TrieDB().Commit(transRoot, false); err != nil {
 		t.Errorf("can not commit trie %v to persistent database", transRoot.Hex())
 	}
 
@@ -114,7 +114,7 @@ func TestIntermediateLeaks(t *testing.T) {
 	if err != nil {
 		t.Fatalf("failed to commit final state: %v", err)
 	}
-	if err = finalState.Database().TrieDB().Commit(finalRoot, false, nil); err != nil {
+	if err = finalState.Database().TrieDB().Commit(finalRoot, false); err != nil {
 		t.Errorf("can not commit trie %v to persistent database", finalRoot.Hex())
 	}
 
@@ -948,7 +948,7 @@ func TestFlushOrderDataLoss(t *testing.T) {
 	if err := statedb.TrieDB().Cap(1024); err != nil {
 		t.Fatalf("failed to cap trie dirty cache: %v", err)
 	}
-	if err := statedb.TrieDB().Commit(root, false, nil); err != nil {
+	if err := statedb.TrieDB().Commit(root, false); err != nil {
 		t.Fatalf("failed to commit state trie: %v", err)
 	}
 	// Reopen the state trie from flushed disk and verify it

core/state/sync_test.go

@@ -174,7 +174,7 @@ func testIterativeStateSync(t *testing.T, count int, commit bool, bypath bool) {
 	// Create a random state to copy
 	_, srcDb, srcRoot, srcAccounts := makeTestState()
 	if commit {
-		srcDb.TrieDB().Commit(srcRoot, false, nil)
+		srcDb.TrieDB().Commit(srcRoot, false)
 	}
 	srcTrie, _ := trie.New(trie.StateTrieID(srcRoot), srcDb.TrieDB())
 

eth/protocols/eth/handler_test.go

@@ -111,7 +111,7 @@ func newTestBackendWithGenerator(blocks int, shanghai bool, generator func(int,
 		panic(err)
 	}
 	for _, block := range bs {
-		chain.StateCache().TrieDB().Commit(block.Root(), false, nil)
+		chain.StateCache().TrieDB().Commit(block.Root(), false)
 	}
 	txconfig := txpool.DefaultConfig
 	txconfig.Journal = "" // Don't litter the disk with test journals

light/postprocess.go

@@ -221,7 +221,7 @@ func (c *ChtIndexerBackend) Commit() error {
 		if err := c.triedb.Update(trie.NewWithNodeSet(nodes)); err != nil {
 			return err
 		}
-		if err := c.triedb.Commit(root, false, nil); err != nil {
+		if err := c.triedb.Commit(root, false); err != nil {
 			return err
 		}
 	}
@@ -467,7 +467,7 @@ func (b *BloomTrieIndexerBackend) Commit() error {
 		if err := b.triedb.Update(trie.NewWithNodeSet(nodes)); err != nil {
 			return err
 		}
-		if err := b.triedb.Commit(root, false, nil); err != nil {
+		if err := b.triedb.Commit(root, false); err != nil {
 			return err
 		}
 	}

tests/fuzzers/stacktrie/trie_fuzzer.go

@@ -190,7 +190,7 @@ func (f *fuzzer) fuzz() int {
 		dbA.Update(trie.NewWithNodeSet(nodes))
 	}
 	// Flush memdb -> disk (sponge)
-	dbA.Commit(rootA, false, nil)
+	dbA.Commit(rootA, false)
 
 	// Stacktrie requires sorted insertion
 	sort.Sort(vals)

trie/database.go

@@ -632,7 +632,7 @@ func (db *Database) Cap(limit common.StorageSize) error {
 //
 // Note, this method is a non-synchronized mutator. It is unsafe to call this
 // concurrently with other mutators.
-func (db *Database) Commit(node common.Hash, report bool, callback func(common.Hash)) error {
+func (db *Database) Commit(node common.Hash, report bool) error {
 	// Create a database batch to flush persistent data out. It is important that
 	// outside code doesn't see an inconsistent state (referenced data removed from
 	// memory cache during commit but not yet in persistent storage). This is ensured
@@ -650,7 +650,7 @@ func (db *Database) Commit(node common.Hash, report bool, callback func(common.H
 	nodes, storage := len(db.dirties), db.dirtiesSize
 
 	uncacher := &cleaner{db}
-	if err := db.commit(node, batch, uncacher, callback); err != nil {
+	if err := db.commit(node, batch, uncacher); err != nil {
 		log.Error("Failed to commit trie from trie database", "err", err)
 		return err
 	}
@@ -687,7 +687,7 @@ func (db *Database) Commit(node common.Hash, report bool, callback func(common.H
 }
 
 // commit is the private locked version of Commit.
-func (db *Database) commit(hash common.Hash, batch ethdb.Batch, uncacher *cleaner, callback func(common.Hash)) error {
+func (db *Database) commit(hash common.Hash, batch ethdb.Batch, uncacher *cleaner) error {
 	// If the node does not exist, it's a previously committed node
 	node, ok := db.dirties[hash]
 	if !ok {
@@ -696,7 +696,7 @@ func (db *Database) commit(hash common.Hash, batch ethdb.Batch, uncacher *cleane
 	var err error
 	node.forChilds(func(child common.Hash) {
 		if err == nil {
-			err = db.commit(child, batch, uncacher, callback)
+			err = db.commit(child, batch, uncacher)
 		}
 	})
 	if err != nil {
@@ -704,9 +704,6 @@ func (db *Database) commit(hash common.Hash, batch ethdb.Batch, uncacher *cleane
 	}
 	// If we've reached an optimal batch size, commit and start over
 	rawdb.WriteLegacyTrieNode(batch, hash, node.rlp())
-	if callback != nil {
-		callback(hash)
-	}
 	if batch.ValueSize() >= ethdb.IdealBatchSize {
 		if err := batch.Write(); err != nil {
 			return err

trie/encoding_test.go

@@ -78,17 +78,17 @@ func TestHexKeybytes(t *testing.T) {
 }
 
 func TestHexToCompactInPlace(t *testing.T) {
-	for i, keyS := range []string{
+	for i, key := range []string{
 		"00",
 		"060a040c0f000a090b040803010801010900080d090a0a0d0903000b10",
 		"10",
 	} {
-		hexBytes, _ := hex.DecodeString(keyS)
+		hexBytes, _ := hex.DecodeString(key)
 		exp := hexToCompact(hexBytes)
 		sz := hexToCompactInPlace(hexBytes)
 		got := hexBytes[:sz]
 		if !bytes.Equal(exp, got) {
-			t.Fatalf("test %d: encoding err\ninp %v\ngot %x\nexp %x\n", i, keyS, got, exp)
+			t.Fatalf("test %d: encoding err\ninp %v\ngot %x\nexp %x\n", i, key, got, exp)
 		}
 	}
 }

trie/iterator.go

@@ -22,9 +22,15 @@ import (
 	"errors"
 
 	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/ethdb"
 )
 
+// NodeResolver is used for looking up trie nodes before reaching into the real
+// persistent layer. This is not mandatory, rather is an optimization for cases
+// where trie nodes can be recovered from some external mechanism without reading
+// from disk. In those cases, this resolver allows short circuiting accesses and
+// returning them from memory.
+type NodeResolver func(owner common.Hash, path []byte, hash common.Hash) []byte
+
 // Iterator is a key-value trie iterator that traverses a Trie.
 type Iterator struct {
 	nodeIt NodeIterator
@@ -107,8 +113,8 @@ type NodeIterator interface {
 	// to the value after calling Next.
 	LeafProof() [][]byte
 
-	// AddResolver sets an intermediate database to use for looking up trie nodes
-	// before reaching into the real persistent layer.
+	// AddResolver sets a node resolver to use for looking up trie nodes before
+	// reaching into the real persistent layer.
 	//
 	// This is not required for normal operation, rather is an optimization for
 	// cases where trie nodes can be recovered from some external mechanism without
@@ -118,7 +124,7 @@ type NodeIterator interface {
 	// Before adding a similar mechanism to any other place in Geth, consider
 	// making trie.Database an interface and wrapping at that level. It's a huge
 	// refactor, but it could be worth it if another occurrence arises.
-	AddResolver(ethdb.KeyValueReader)
+	AddResolver(NodeResolver)
 }
 
 // nodeIteratorState represents the iteration state at one particular node of the
@@ -137,7 +143,7 @@ type nodeIterator struct {
 	path  []byte               // Path to the current node
 	err   error                // Failure set in case of an internal error in the iterator
 
-	resolver ethdb.KeyValueReader // Optional intermediate resolver above the disk layer
+	resolver NodeResolver // optional node resolver for avoiding disk hits
 }
 
 // errIteratorEnd is stored in nodeIterator.err when iteration is done.
@@ -165,7 +171,7 @@ func newNodeIterator(trie *Trie, start []byte) NodeIterator {
 	return it
 }
 
-func (it *nodeIterator) AddResolver(resolver ethdb.KeyValueReader) {
+func (it *nodeIterator) AddResolver(resolver NodeResolver) {
 	it.resolver = resolver
 }
 
@@ -369,7 +375,7 @@ func (it *nodeIterator) peekSeek(seekKey []byte) (*nodeIteratorState, *int, []by
 
 func (it *nodeIterator) resolveHash(hash hashNode, path []byte) (node, error) {
 	if it.resolver != nil {
-		if blob, err := it.resolver.Get(hash); err == nil && len(blob) > 0 {
+		if blob := it.resolver(it.trie.owner, path, common.BytesToHash(hash)); len(blob) > 0 {
 			if resolved, err := decodeNode(hash, blob); err == nil {
 				return resolved, nil
 			}
@@ -385,7 +391,7 @@ func (it *nodeIterator) resolveHash(hash hashNode, path []byte) (node, error) {
 
 func (it *nodeIterator) resolveBlob(hash hashNode, path []byte) ([]byte, error) {
 	if it.resolver != nil {
-		if blob, err := it.resolver.Get(hash); err == nil && len(blob) > 0 {
+		if blob := it.resolver(it.trie.owner, path, common.BytesToHash(hash)); len(blob) > 0 {
 			return blob, nil
 		}
 	}
@@ -589,7 +595,7 @@ func (it *differenceIterator) NodeBlob() []byte {
 	return it.b.NodeBlob()
 }
 
-func (it *differenceIterator) AddResolver(resolver ethdb.KeyValueReader) {
+func (it *differenceIterator) AddResolver(resolver NodeResolver) {
 	panic("not implemented")
 }
 
@@ -704,7 +710,7 @@ func (it *unionIterator) NodeBlob() []byte {
 	return (*it.items)[0].NodeBlob()
 }
 
-func (it *unionIterator) AddResolver(resolver ethdb.KeyValueReader) {
+func (it *unionIterator) AddResolver(resolver NodeResolver) {
 	panic("not implemented")
 }
 

trie/iterator_test.go

@@ -337,7 +337,7 @@ func testIteratorContinueAfterError(t *testing.T, memonly bool) {
 	_, nodes, _ := tr.Commit(false)
 	triedb.Update(NewWithNodeSet(nodes))
 	if !memonly {
-		triedb.Commit(tr.Hash(), true, nil)
+		triedb.Commit(tr.Hash(), false)
 	}
 	wantNodeCount := checkIteratorNoDups(t, tr.NodeIterator(nil), nil)
 
@@ -429,7 +429,7 @@ func testIteratorContinueAfterSeekError(t *testing.T, memonly bool) {
 	root, nodes, _ := ctr.Commit(false)
 	triedb.Update(NewWithNodeSet(nodes))
 	if !memonly {
-		triedb.Commit(root, true, nil)
+		triedb.Commit(root, false)
 	}
 	barNodeHash := common.HexToHash("05041990364eb72fcb1127652ce40d8bab765f2bfe53225b1170d276cc101c2e")
 	var (

trie/stacktrie_test.go

@@ -255,7 +255,6 @@ func TestValLength56(t *testing.T) {
 func TestUpdateSmallNodes(t *testing.T) {
 	st := NewStackTrie(nil)
 	nt := NewEmpty(NewDatabase(rawdb.NewMemoryDatabase()))
-
 	kvs := []struct {
 		K string
 		V string
@@ -284,7 +283,6 @@ func TestUpdateVariableKeys(t *testing.T) {
 	t.SkipNow()
 	st := NewStackTrie(nil)
 	nt := NewEmpty(NewDatabase(rawdb.NewMemoryDatabase()))
-
 	kvs := []struct {
 		K string
 		V string

trie/trie_test.go

@@ -86,7 +86,7 @@ func testMissingNode(t *testing.T, memonly bool) {
 	root, nodes, _ := trie.Commit(false)
 	triedb.Update(NewWithNodeSet(nodes))
 	if !memonly {
-		triedb.Commit(root, true, nil)
+		triedb.Commit(root, false)
 	}
 
 	trie, _ = New(TrieID(root), triedb)
@@ -791,29 +791,23 @@ func (b *spongeBatch) Reset()                              {}
 func (b *spongeBatch) Replay(w ethdb.KeyValueWriter) error { return nil }
 
 // TestCommitSequence tests that the trie.Commit operation writes the elements of the trie
-// in the expected order, and calls the callbacks in the expected order.
+// in the expected order.
 // The test data was based on the 'master' code, and is basically random. It can be used
 // to check whether changes to the trie modifies the write order or data in any way.
 func TestCommitSequence(t *testing.T) {
 	for i, tc := range []struct {
-		count              int
-		expWriteSeqHash    []byte
-		expCallbackSeqHash []byte
+		count           int
+		expWriteSeqHash []byte
 	}{
-		{20, common.FromHex("873c78df73d60e59d4a2bcf3716e8bfe14554549fea2fc147cb54129382a8066"),
-			common.FromHex("ff00f91ac05df53b82d7f178d77ada54fd0dca64526f537034a5dbe41b17df2a")},
-		{200, common.FromHex("ba03d891bb15408c940eea5ee3d54d419595102648d02774a0268d892add9c8e"),
-			common.FromHex("f3cd509064c8d319bbdd1c68f511850a902ad275e6ed5bea11547e23d492a926")},
-		{2000, common.FromHex("f7a184f20df01c94f09537401d11e68d97ad0c00115233107f51b9c287ce60c7"),
-			common.FromHex("ff795ea898ba1e4cfed4a33b4cf5535a347a02cf931f88d88719faf810f9a1c9")},
+		{20, common.FromHex("873c78df73d60e59d4a2bcf3716e8bfe14554549fea2fc147cb54129382a8066")},
+		{200, common.FromHex("ba03d891bb15408c940eea5ee3d54d419595102648d02774a0268d892add9c8e")},
+		{2000, common.FromHex("f7a184f20df01c94f09537401d11e68d97ad0c00115233107f51b9c287ce60c7")},
 	} {
 		addresses, accounts := makeAccounts(tc.count)
 		// This spongeDb is used to check the sequence of disk-db-writes
 		s := &spongeDb{sponge: sha3.NewLegacyKeccak256()}
 		db := NewDatabase(rawdb.NewDatabase(s))
 		trie := NewEmpty(db)
-		// Another sponge is used to check the callback-sequence
-		callbackSponge := sha3.NewLegacyKeccak256()
 		// Fill the trie with elements
 		for i := 0; i < tc.count; i++ {
 			trie.Update(crypto.Keccak256(addresses[i][:]), accounts[i])
@@ -822,16 +816,10 @@ func TestCommitSequence(t *testing.T) {
 		root, nodes, _ := trie.Commit(false)
 		db.Update(NewWithNodeSet(nodes))
 		// Flush memdb -> disk (sponge)
-		db.Commit(root, false, func(c common.Hash) {
-			// And spongify the callback-order
-			callbackSponge.Write(c[:])
-		})
+		db.Commit(root, false)
 		if got, exp := s.sponge.Sum(nil), tc.expWriteSeqHash; !bytes.Equal(got, exp) {
 			t.Errorf("test %d, disk write sequence wrong:\ngot %x exp %x\n", i, got, exp)
 		}
-		if got, exp := callbackSponge.Sum(nil), tc.expCallbackSeqHash; !bytes.Equal(got, exp) {
-			t.Errorf("test %d, call back sequence wrong:\ngot: %x exp %x\n", i, got, exp)
-		}
 	}
 }
 
@@ -839,24 +827,18 @@ func TestCommitSequence(t *testing.T) {
 // but uses random blobs instead of 'accounts'
 func TestCommitSequenceRandomBlobs(t *testing.T) {
 	for i, tc := range []struct {
-		count              int
-		expWriteSeqHash    []byte
-		expCallbackSeqHash []byte
+		count           int
+		expWriteSeqHash []byte
 	}{
-		{20, common.FromHex("8e4a01548551d139fa9e833ebc4e66fc1ba40a4b9b7259d80db32cff7b64ebbc"),
-			common.FromHex("450238d73bc36dc6cc6f926987e5428535e64be403877c4560e238a52749ba24")},
-		{200, common.FromHex("6869b4e7b95f3097a19ddb30ff735f922b915314047e041614df06958fc50554"),
-			common.FromHex("0ace0b03d6cb8c0b82f6289ef5b1a1838306b455a62dafc63cada8e2924f2550")},
-		{2000, common.FromHex("444200e6f4e2df49f77752f629a96ccf7445d4698c164f962bbd85a0526ef424"),
-			common.FromHex("117d30dafaa62a1eed498c3dfd70982b377ba2b46dd3e725ed6120c80829e518")},
+		{20, common.FromHex("8e4a01548551d139fa9e833ebc4e66fc1ba40a4b9b7259d80db32cff7b64ebbc")},
+		{200, common.FromHex("6869b4e7b95f3097a19ddb30ff735f922b915314047e041614df06958fc50554")},
+		{2000, common.FromHex("444200e6f4e2df49f77752f629a96ccf7445d4698c164f962bbd85a0526ef424")},
 	} {
 		prng := rand.New(rand.NewSource(int64(i)))
 		// This spongeDb is used to check the sequence of disk-db-writes
 		s := &spongeDb{sponge: sha3.NewLegacyKeccak256()}
 		db := NewDatabase(rawdb.NewDatabase(s))
 		trie := NewEmpty(db)
-		// Another sponge is used to check the callback-sequence
-		callbackSponge := sha3.NewLegacyKeccak256()
 		// Fill the trie with elements
 		for i := 0; i < tc.count; i++ {
 			key := make([]byte, 32)
@@ -875,16 +857,10 @@ func TestCommitSequenceRandomBlobs(t *testing.T) {
 		root, nodes, _ := trie.Commit(false)
 		db.Update(NewWithNodeSet(nodes))
 		// Flush memdb -> disk (sponge)
-		db.Commit(root, false, func(c common.Hash) {
-			// And spongify the callback-order
-			callbackSponge.Write(c[:])
-		})
+		db.Commit(root, false)
 		if got, exp := s.sponge.Sum(nil), tc.expWriteSeqHash; !bytes.Equal(got, exp) {
 			t.Fatalf("test %d, disk write sequence wrong:\ngot %x exp %x\n", i, got, exp)
 		}
-		if got, exp := callbackSponge.Sum(nil), tc.expCallbackSeqHash; !bytes.Equal(got, exp) {
-			t.Fatalf("test %d, call back sequence wrong:\ngot: %x exp %x\n", i, got, exp)
-		}
 	}
 }
 
@@ -920,7 +896,7 @@ func TestCommitSequenceStackTrie(t *testing.T) {
 		root, nodes, _ := trie.Commit(false)
 		// Flush memdb -> disk (sponge)
 		db.Update(NewWithNodeSet(nodes))
-		db.Commit(root, false, nil)
+		db.Commit(root, false)
 		// And flush stacktrie -> disk
 		stRoot, err := stTrie.Commit()
 		if err != nil {
@@ -968,7 +944,7 @@ func TestCommitSequenceSmallRoot(t *testing.T) {
 	root, nodes, _ := trie.Commit(false)
 	// Flush memdb -> disk (sponge)
 	db.Update(NewWithNodeSet(nodes))
-	db.Commit(root, false, nil)
+	db.Commit(root, false)
 	// And flush stacktrie -> disk
 	stRoot, err := stTrie.Commit()
 	if err != nil {