Merge pull request #2455 from zsfelfoldi/chaindb

core: improved chain db performance by using sequential keys

9 files changed, 434 insertions, 205 deletions

diff --git a/core/bench_test.go b/core/bench_test.go
index ac5b57bc8..c6029499a 100644
--- a/core/bench_test.go
+++ b/core/bench_test.go
@@ -176,3 +176,122 @@ func benchInsertChain(b *testing.B, disk bool, gen func(int, *BlockGen)) {
 		b.Fatalf("insert error (block %d): %v\n", i, err)
 	}
 }
+
+func BenchmarkChainRead_header_10k(b *testing.B) {
+	benchReadChain(b, false, 10000)
+}
+func BenchmarkChainRead_full_10k(b *testing.B) {
+	benchReadChain(b, true, 10000)
+}
+func BenchmarkChainRead_header_100k(b *testing.B) {
+	benchReadChain(b, false, 100000)
+}
+func BenchmarkChainRead_full_100k(b *testing.B) {
+	benchReadChain(b, true, 100000)
+}
+func BenchmarkChainRead_header_500k(b *testing.B) {
+	benchReadChain(b, false, 500000)
+}
+func BenchmarkChainRead_full_500k(b *testing.B) {
+	benchReadChain(b, true, 500000)
+}
+func BenchmarkChainWrite_header_10k(b *testing.B) {
+	benchWriteChain(b, false, 10000)
+}
+func BenchmarkChainWrite_full_10k(b *testing.B) {
+	benchWriteChain(b, true, 10000)
+}
+func BenchmarkChainWrite_header_100k(b *testing.B) {
+	benchWriteChain(b, false, 100000)
+}
+func BenchmarkChainWrite_full_100k(b *testing.B) {
+	benchWriteChain(b, true, 100000)
+}
+func BenchmarkChainWrite_header_500k(b *testing.B) {
+	benchWriteChain(b, false, 500000)
+}
+func BenchmarkChainWrite_full_500k(b *testing.B) {
+	benchWriteChain(b, true, 500000)
+}
+
+// makeChainForBench writes a given number of headers or empty blocks/receipts
+// into a database.
+func makeChainForBench(db ethdb.Database, full bool, count uint64) {
+	var hash common.Hash
+	for n := uint64(0); n < count; n++ {
+		header := &types.Header{
+			Coinbase:    common.Address{},
+			Number:      big.NewInt(int64(n)),
+			ParentHash:  hash,
+			Difficulty:  big.NewInt(1),
+			UncleHash:   types.EmptyUncleHash,
+			TxHash:      types.EmptyRootHash,
+			ReceiptHash: types.EmptyRootHash,
+		}
+		hash = header.Hash()
+		WriteHeader(db, header)
+		WriteCanonicalHash(db, hash, n)
+		WriteTd(db, hash, n, big.NewInt(int64(n+1)))
+		if full || n == 0 {
+			block := types.NewBlockWithHeader(header)
+			WriteBody(db, hash, n, block.Body())
+			WriteBlockReceipts(db, hash, n, nil)
+		}
+	}
+}
+
+func benchWriteChain(b *testing.B, full bool, count uint64) {
+	for i := 0; i < b.N; i++ {
+		dir, err := ioutil.TempDir("", "eth-chain-bench")
+		if err != nil {
+			b.Fatalf("cannot create temporary directory: %v", err)
+		}
+		db, err := ethdb.NewLDBDatabase(dir, 128, 1024)
+		if err != nil {
+			b.Fatalf("error opening database at %v: %v", dir, err)
+		}
+		makeChainForBench(db, full, count)
+		db.Close()
+		os.RemoveAll(dir)
+	}
+}
+
+func benchReadChain(b *testing.B, full bool, count uint64) {
+	dir, err := ioutil.TempDir("", "eth-chain-bench")
+	if err != nil {
+		b.Fatalf("cannot create temporary directory: %v", err)
+	}
+	defer os.RemoveAll(dir)
+
+	db, err := ethdb.NewLDBDatabase(dir, 128, 1024)
+	if err != nil {
+		b.Fatalf("error opening database at %v: %v", dir, err)
+	}
+	makeChainForBench(db, full, count)
+	db.Close()
+
+	b.ReportAllocs()
+	b.ResetTimer()
+
+	for i := 0; i < b.N; i++ {
+		db, err := ethdb.NewLDBDatabase(dir, 128, 1024)
+		if err != nil {
+			b.Fatalf("error opening database at %v: %v", dir, err)
+		}
+		chain, err := NewBlockChain(db, testChainConfig(), FakePow{}, new(event.TypeMux))
+		if err != nil {
+			b.Fatalf("error creating chain: %v", err)
+		}
+
+		for n := uint64(0); n < count; n++ {
+			header := chain.GetHeaderByNumber(n)
+			if full {
+				hash := header.Hash()
+				GetBody(db, hash, n)
+				GetBlockReceipts(db, hash, n)
+			}
+		}
+
+		db.Close()
+	}
+}
diff --git a/core/block_validator.go b/core/block_validator.go
index 801d2572b..f777b9f23 100644
--- a/core/block_validator.go
+++ b/core/block_validator.go
@@ -72,7 +72,7 @@ func (v *BlockValidator) ValidateBlock(block *types.Block) error {
 			return &KnownBlockError{block.Number(), block.Hash()}
 		}
 	}
-	parent := v.bc.GetBlock(block.ParentHash())
+	parent := v.bc.GetBlock(block.ParentHash(), block.NumberU64()-1)
 	if parent == nil {
 		return ParentError(block.ParentHash())
 	}
diff --git a/core/blockchain.go b/core/blockchain.go
index bd84adfe9..95bada5ee 100644
--- a/core/blockchain.go
+++ b/core/blockchain.go
@@ -54,9 +54,7 @@ var (
 )
 
 const (
-	headerCacheLimit    = 512
 	bodyCacheLimit      = 256
-	tdCacheLimit        = 1024
 	blockCacheLimit     = 256
 	maxFutureBlocks     = 256
 	maxTimeFutureBlocks = 30
@@ -151,7 +149,7 @@ func NewBlockChain(chainDb ethdb.Database, config *ChainConfig, pow pow.PoW, mux
 	}
 	// Check the current state of the block hashes and make sure that we do not have any of the bad blocks in our chain
 	for hash, _ := range BadHashes {
-		if header := bc.GetHeader(hash); header != nil {
+		if header := bc.GetHeaderByHash(hash); header != nil {
 			glog.V(logger.Error).Infof("Found bad hash, rewinding chain to block #%d [%x…]", header.Number, header.ParentHash[:4])
 			bc.SetHead(header.Number.Uint64() - 1)
 			glog.V(logger.Error).Infoln("Chain rewind was successful, resuming normal operation")
@@ -175,7 +173,7 @@ func (self *BlockChain) loadLastState() error {
 		// Corrupt or empty database, init from scratch
 		self.Reset()
 	} else {
-		if block := self.GetBlock(head); block != nil {
+		if block := self.GetBlockByHash(head); block != nil {
 			// Block found, set as the current head
 			self.currentBlock = block
 		} else {
@@ -186,7 +184,7 @@ func (self *BlockChain) loadLastState() error {
 	// Restore the last known head header
 	currentHeader := self.currentBlock.Header()
 	if head := GetHeadHeaderHash(self.chainDb); head != (common.Hash{}) {
-		if header := self.GetHeader(head); header != nil {
+		if header := self.GetHeaderByHash(head); header != nil {
 			currentHeader = header
 		}
 	}
@@ -194,16 +192,16 @@ func (self *BlockChain) loadLastState() error {
 	// Restore the last known head fast block
 	self.currentFastBlock = self.currentBlock
 	if head := GetHeadFastBlockHash(self.chainDb); head != (common.Hash{}) {
-		if block := self.GetBlock(head); block != nil {
+		if block := self.GetBlockByHash(head); block != nil {
 			self.currentFastBlock = block
 		}
 	}
 	// Issue a status log and return
-	headerTd := self.GetTd(self.hc.CurrentHeader().Hash())
-	blockTd := self.GetTd(self.currentBlock.Hash())
-	fastTd := self.GetTd(self.currentFastBlock.Hash())
+	headerTd := self.GetTd(currentHeader.Hash(), currentHeader.Number.Uint64())
+	blockTd := self.GetTd(self.currentBlock.Hash(), self.currentBlock.NumberU64())
+	fastTd := self.GetTd(self.currentFastBlock.Hash(), self.currentFastBlock.NumberU64())
 
-	glog.V(logger.Info).Infof("Last header: #%d [%x…] TD=%v", self.hc.CurrentHeader().Number, self.hc.CurrentHeader().Hash().Bytes()[:4], headerTd)
+	glog.V(logger.Info).Infof("Last header: #%d [%x…] TD=%v", currentHeader.Number, currentHeader.Hash().Bytes()[:4], headerTd)
 	glog.V(logger.Info).Infof("Last block: #%d [%x…] TD=%v", self.currentBlock.Number(), self.currentBlock.Hash().Bytes()[:4], blockTd)
 	glog.V(logger.Info).Infof("Fast block: #%d [%x…] TD=%v", self.currentFastBlock.Number(), self.currentFastBlock.Hash().Bytes()[:4], fastTd)
 
@@ -218,8 +216,8 @@ func (bc *BlockChain) SetHead(head uint64) {
 	bc.mu.Lock()
 	defer bc.mu.Unlock()
 
-	delFn := func(hash common.Hash) {
-		DeleteBody(bc.chainDb, hash)
+	delFn := func(hash common.Hash, num uint64) {
+		DeleteBody(bc.chainDb, hash, num)
 	}
 	bc.hc.SetHead(head, delFn)
 
@@ -230,11 +228,12 @@ func (bc *BlockChain) SetHead(head uint64) {
 	bc.futureBlocks.Purge()
 
 	// Update all computed fields to the new head
-	if bc.currentBlock != nil && bc.hc.CurrentHeader().Number.Uint64() < bc.currentBlock.NumberU64() {
-		bc.currentBlock = bc.GetBlock(bc.hc.CurrentHeader().Hash())
+	currentHeader := bc.hc.CurrentHeader()
+	if bc.currentBlock != nil && currentHeader.Number.Uint64() < bc.currentBlock.NumberU64() {
+		bc.currentBlock = bc.GetBlock(currentHeader.Hash(), currentHeader.Number.Uint64())
 	}
-	if bc.currentFastBlock != nil && bc.hc.CurrentHeader().Number.Uint64() < bc.currentFastBlock.NumberU64() {
-		bc.currentFastBlock = bc.GetBlock(bc.hc.CurrentHeader().Hash())
+	if bc.currentFastBlock != nil && currentHeader.Number.Uint64() < bc.currentFastBlock.NumberU64() {
+		bc.currentFastBlock = bc.GetBlock(currentHeader.Hash(), currentHeader.Number.Uint64())
 	}
 
 	if bc.currentBlock == nil {
@@ -257,7 +256,7 @@ func (bc *BlockChain) SetHead(head uint64) {
 // irrelevant what the chain contents were prior.
 func (self *BlockChain) FastSyncCommitHead(hash common.Hash) error {
 	// Make sure that both the block as well at its state trie exists
-	block := self.GetBlock(hash)
+	block := self.GetBlockByHash(hash)
 	if block == nil {
 		return fmt.Errorf("non existent block [%x…]", hash[:4])
 	}
@@ -313,7 +312,7 @@ func (self *BlockChain) Status() (td *big.Int, currentBlock common.Hash, genesis
 	self.mu.RLock()
 	defer self.mu.RUnlock()
 
-	return self.GetTd(self.currentBlock.Hash()), self.currentBlock.Hash(), self.genesisBlock.Hash()
+	return self.GetTd(self.currentBlock.Hash(), self.currentBlock.NumberU64()), self.currentBlock.Hash(), self.genesisBlock.Hash()
 }
 
 // SetProcessor sets the processor required for making state modifications.
@@ -367,7 +366,7 @@ func (bc *BlockChain) ResetWithGenesisBlock(genesis *types.Block) {
 	defer bc.mu.Unlock()
 
 	// Prepare the genesis block and reinitialise the chain
-	if err := bc.hc.WriteTd(genesis.Hash(), genesis.Difficulty()); err != nil {
+	if err := bc.hc.WriteTd(genesis.Hash(), genesis.NumberU64(), genesis.Difficulty()); err != nil {
 		glog.Fatalf("failed to write genesis block TD: %v", err)
 	}
 	if err := WriteBlock(bc.chainDb, genesis); err != nil {
@@ -457,7 +456,7 @@ func (self *BlockChain) GetBody(hash common.Hash) *types.Body {
 		body := cached.(*types.Body)
 		return body
 	}
-	body := GetBody(self.chainDb, hash)
+	body := GetBody(self.chainDb, hash, self.hc.GetBlockNumber(hash))
 	if body == nil {
 		return nil
 	}
@@ -473,7 +472,7 @@ func (self *BlockChain) GetBodyRLP(hash common.Hash) rlp.RawValue {
 	if cached, ok := self.bodyRLPCache.Get(hash); ok {
 		return cached.(rlp.RawValue)
 	}
-	body := GetBodyRLP(self.chainDb, hash)
+	body := GetBodyRLP(self.chainDb, hash, self.hc.GetBlockNumber(hash))
 	if len(body) == 0 {
 		return nil
 	}
@@ -485,14 +484,14 @@ func (self *BlockChain) GetBodyRLP(hash common.Hash) rlp.RawValue {
 // HasBlock checks if a block is fully present in the database or not, caching
 // it if present.
 func (bc *BlockChain) HasBlock(hash common.Hash) bool {
-	return bc.GetBlock(hash) != nil
+	return bc.GetBlockByHash(hash) != nil
 }
 
 // HasBlockAndState checks if a block and associated state trie is fully present
 // in the database or not, caching it if present.
 func (bc *BlockChain) HasBlockAndState(hash common.Hash) bool {
 	// Check first that the block itself is known
-	block := bc.GetBlock(hash)
+	block := bc.GetBlockByHash(hash)
 	if block == nil {
 		return false
 	}
@@ -501,13 +500,14 @@ func (bc *BlockChain) HasBlockAndState(hash common.Hash) bool {
 	return err == nil
 }
 
-// GetBlock retrieves a block from the database by hash, caching it if found.
-func (self *BlockChain) GetBlock(hash common.Hash) *types.Block {
+// GetBlock retrieves a block from the database by hash and number,
+// caching it if found.
+func (self *BlockChain) GetBlock(hash common.Hash, number uint64) *types.Block {
 	// Short circuit if the block's already in the cache, retrieve otherwise
 	if block, ok := self.blockCache.Get(hash); ok {
 		return block.(*types.Block)
 	}
-	block := GetBlock(self.chainDb, hash)
+	block := GetBlock(self.chainDb, hash, number)
 	if block == nil {
 		return nil
 	}
@@ -516,6 +516,11 @@ func (self *BlockChain) GetBlock(hash common.Hash) *types.Block {
 	return block
 }
 
+// GetBlockByHash retrieves a block from the database by hash, caching it if found.
+func (self *BlockChain) GetBlockByHash(hash common.Hash) *types.Block {
+	return self.GetBlock(hash, self.hc.GetBlockNumber(hash))
+}
+
 // GetBlockByNumber retrieves a block from the database by number, caching it
 // (associated with its hash) if found.
 func (self *BlockChain) GetBlockByNumber(number uint64) *types.Block {
@@ -523,19 +528,21 @@ func (self *BlockChain) GetBlockByNumber(number uint64) *types.Block {
 	if hash == (common.Hash{}) {
 		return nil
 	}
-	return self.GetBlock(hash)
+	return self.GetBlock(hash, number)
 }
 
 // [deprecated by eth/62]
 // GetBlocksFromHash returns the block corresponding to hash and up to n-1 ancestors.
 func (self *BlockChain) GetBlocksFromHash(hash common.Hash, n int) (blocks []*types.Block) {
+	number := self.hc.GetBlockNumber(hash)
 	for i := 0; i < n; i++ {
-		block := self.GetBlock(hash)
+		block := self.GetBlock(hash, number)
 		if block == nil {
 			break
 		}
 		blocks = append(blocks, block)
 		hash = block.ParentHash()
+		number--
 	}
 	return
 }
@@ -546,7 +553,7 @@ func (self *BlockChain) GetUnclesInChain(block *types.Block, length int) []*type
 	uncles := []*types.Header{}
 	for i := 0; block != nil && i < length; i++ {
 		uncles = append(uncles, block.Uncles()...)
-		block = self.GetBlock(block.ParentHash())
+		block = self.GetBlock(block.ParentHash(), block.NumberU64()-1)
 	}
 	return uncles
 }
@@ -596,15 +603,16 @@ func (self *BlockChain) Rollback(chain []common.Hash) {
 	for i := len(chain) - 1; i >= 0; i-- {
 		hash := chain[i]
 
-		if self.hc.CurrentHeader().Hash() == hash {
-			self.hc.SetCurrentHeader(self.GetHeader(self.hc.CurrentHeader().ParentHash))
+		currentHeader := self.hc.CurrentHeader()
+		if currentHeader.Hash() == hash {
+			self.hc.SetCurrentHeader(self.GetHeader(currentHeader.ParentHash, currentHeader.Number.Uint64()-1))
 		}
 		if self.currentFastBlock.Hash() == hash {
-			self.currentFastBlock = self.GetBlock(self.currentFastBlock.ParentHash())
+			self.currentFastBlock = self.GetBlock(self.currentFastBlock.ParentHash(), self.currentFastBlock.NumberU64()-1)
 			WriteHeadFastBlockHash(self.chainDb, self.currentFastBlock.Hash())
 		}
 		if self.currentBlock.Hash() == hash {
-			self.currentBlock = self.GetBlock(self.currentBlock.ParentHash())
+			self.currentBlock = self.GetBlock(self.currentBlock.ParentHash(), self.currentBlock.NumberU64()-1)
 			WriteHeadBlockHash(self.chainDb, self.currentBlock.Hash())
 		}
 	}
@@ -678,13 +686,13 @@ func (self *BlockChain) InsertReceiptChain(blockChain types.Blocks, receiptChain
 				}
 			}
 			// Write all the data out into the database
-			if err := WriteBody(self.chainDb, block.Hash(), block.Body()); err != nil {
+			if err := WriteBody(self.chainDb, block.Hash(), block.NumberU64(), block.Body()); err != nil {
 				errs[index] = fmt.Errorf("failed to write block body: %v", err)
 				atomic.AddInt32(&failed, 1)
 				glog.Fatal(errs[index])
 				return
 			}
-			if err := WriteBlockReceipts(self.chainDb, block.Hash(), receipts); err != nil {
+			if err := WriteBlockReceipts(self.chainDb, block.Hash(), block.NumberU64(), receipts); err != nil {
 				errs[index] = fmt.Errorf("failed to write block receipts: %v", err)
 				atomic.AddInt32(&failed, 1)
 				glog.Fatal(errs[index])
@@ -737,7 +745,7 @@ func (self *BlockChain) InsertReceiptChain(blockChain types.Blocks, receiptChain
 	// Update the head fast sync block if better
 	self.mu.Lock()
 	head := blockChain[len(errs)-1]
-	if self.GetTd(self.currentFastBlock.Hash()).Cmp(self.GetTd(head.Hash())) < 0 {
+	if self.GetTd(self.currentFastBlock.Hash(), self.currentFastBlock.NumberU64()).Cmp(self.GetTd(head.Hash(), head.NumberU64())) < 0 {
 		if err := WriteHeadFastBlockHash(self.chainDb, head.Hash()); err != nil {
 			glog.Fatalf("failed to update head fast block hash: %v", err)
 		}
@@ -759,12 +767,12 @@ func (self *BlockChain) WriteBlock(block *types.Block) (status WriteStatus, err
 	defer self.wg.Done()
 
 	// Calculate the total difficulty of the block
-	ptd := self.GetTd(block.ParentHash())
+	ptd := self.GetTd(block.ParentHash(), block.NumberU64()-1)
 	if ptd == nil {
 		return NonStatTy, ParentError(block.ParentHash())
 	}
 
-	localTd := self.GetTd(self.currentBlock.Hash())
+	localTd := self.GetTd(self.currentBlock.Hash(), self.currentBlock.NumberU64())
 	externTd := new(big.Int).Add(block.Difficulty(), ptd)
 
 	// Make sure no inconsistent state is leaked during insertion
@@ -788,7 +796,7 @@ func (self *BlockChain) WriteBlock(block *types.Block) (status WriteStatus, err
 		status = SideStatTy
 	}
 	// Irrelevant of the canonical status, write the block itself to the database
-	if err := self.hc.WriteTd(block.Hash(), externTd); err != nil {
+	if err := self.hc.WriteTd(block.Hash(), block.NumberU64(), externTd); err != nil {
 		glog.Fatalf("failed to write block total difficulty: %v", err)
 	}
 	if err := WriteBlock(self.chainDb, block); err != nil {
@@ -887,7 +895,7 @@ func (self *BlockChain) InsertChain(chain types.Blocks) (int, error) {
 		// Create a new statedb using the parent block and report an
 		// error if it fails.
 		if statedb == nil {
-			statedb, err = state.New(self.GetBlock(block.ParentHash()).Root(), self.chainDb)
+			statedb, err = state.New(self.GetBlock(block.ParentHash(), block.NumberU64()-1).Root(), self.chainDb)
 		} else {
 			err = statedb.Reset(chain[i-1].Root())
 		}
@@ -902,7 +910,7 @@ func (self *BlockChain) InsertChain(chain types.Blocks) (int, error) {
 			return i, err
 		}
 		// Validate the state using the default validator
-		err = self.Validator().ValidateState(block, self.GetBlock(block.ParentHash()), statedb, receipts, usedGas)
+		err = self.Validator().ValidateState(block, self.GetBlock(block.ParentHash(), block.NumberU64()-1), statedb, receipts, usedGas)
 		if err != nil {
 			reportBlock(block, err)
 			return i, err
@@ -916,7 +924,7 @@ func (self *BlockChain) InsertChain(chain types.Blocks) (int, error) {
 		// coalesce logs for later processing
 		coalescedLogs = append(coalescedLogs, logs...)
 
-		if err := WriteBlockReceipts(self.chainDb, block.Hash(), receipts); err != nil {
+		if err := WriteBlockReceipts(self.chainDb, block.Hash(), block.NumberU64(), receipts); err != nil {
 			return i, err
 		}
 
@@ -986,7 +994,7 @@ func (self *BlockChain) reorg(oldBlock, newBlock *types.Block) error {
 		// These logs are later announced as deleted.
 		collectLogs = func(h common.Hash) {
 			// Coalesce logs
-			receipts := GetBlockReceipts(self.chainDb, h)
+			receipts := GetBlockReceipts(self.chainDb, h, self.hc.GetBlockNumber(h))
 			for _, receipt := range receipts {
 				deletedLogs = append(deletedLogs, receipt.Logs...)
 
@@ -998,7 +1006,7 @@ func (self *BlockChain) reorg(oldBlock, newBlock *types.Block) error {
 	// first reduce whoever is higher bound
 	if oldBlock.NumberU64() > newBlock.NumberU64() {
 		// reduce old chain
-		for ; oldBlock != nil && oldBlock.NumberU64() != newBlock.NumberU64(); oldBlock = self.GetBlock(oldBlock.ParentHash()) {
+		for ; oldBlock != nil && oldBlock.NumberU64() != newBlock.NumberU64(); oldBlock = self.GetBlock(oldBlock.ParentHash(), oldBlock.NumberU64()-1) {
 			oldChain = append(oldChain, oldBlock)
 			deletedTxs = append(deletedTxs, oldBlock.Transactions()...)
 
@@ -1006,7 +1014,7 @@ func (self *BlockChain) reorg(oldBlock, newBlock *types.Block) error {
 		}
 	} else {
 		// reduce new chain and append new chain blocks for inserting later on
-		for ; newBlock != nil && newBlock.NumberU64() != oldBlock.NumberU64(); newBlock = self.GetBlock(newBlock.ParentHash()) {
+		for ; newBlock != nil && newBlock.NumberU64() != oldBlock.NumberU64(); newBlock = self.GetBlock(newBlock.ParentHash(), newBlock.NumberU64()-1) {
 			newChain = append(newChain, newBlock)
 		}
 	}
@@ -1029,7 +1037,7 @@ func (self *BlockChain) reorg(oldBlock, newBlock *types.Block) error {
 		deletedTxs = append(deletedTxs, oldBlock.Transactions()...)
 		collectLogs(oldBlock.Hash())
 
-		oldBlock, newBlock = self.GetBlock(oldBlock.ParentHash()), self.GetBlock(newBlock.ParentHash())
+		oldBlock, newBlock = self.GetBlock(oldBlock.ParentHash(), oldBlock.NumberU64()-1), self.GetBlock(newBlock.ParentHash(), newBlock.NumberU64()-1)
 		if oldBlock == nil {
 			return fmt.Errorf("Invalid old chain")
 		}
@@ -1052,7 +1060,7 @@ func (self *BlockChain) reorg(oldBlock, newBlock *types.Block) error {
 		if err := WriteTransactions(self.chainDb, block); err != nil {
 			return err
 		}
-		receipts := GetBlockReceipts(self.chainDb, block.Hash())
+		receipts := GetBlockReceipts(self.chainDb, block.Hash(), block.NumberU64())
 		// write receipts
 		if err := WriteReceipts(self.chainDb, receipts); err != nil {
 			return err
@@ -1187,15 +1195,27 @@ func (self *BlockChain) CurrentHeader() *types.Header {
 }
 
 // GetTd retrieves a block's total difficulty in the canonical chain from the
+// database by hash and number, caching it if found.
+func (self *BlockChain) GetTd(hash common.Hash, number uint64) *big.Int {
+	return self.hc.GetTd(hash, number)
+}
+
+// GetTdByHash retrieves a block's total difficulty in the canonical chain from the
 // database by hash, caching it if found.
-func (self *BlockChain) GetTd(hash common.Hash) *big.Int {
-	return self.hc.GetTd(hash)
+func (self *BlockChain) GetTdByHash(hash common.Hash) *big.Int {
+	return self.hc.GetTdByHash(hash)
+}
+
+// GetHeader retrieves a block header from the database by hash and number,
+// caching it if found.
+func (self *BlockChain) GetHeader(hash common.Hash, number uint64) *types.Header {
+	return self.hc.GetHeader(hash, number)
 }
 
-// GetHeader retrieves a block header from the database by hash, caching it if
+// GetHeaderByHash retrieves a block header from the database by hash, caching it if
 // found.
-func (self *BlockChain) GetHeader(hash common.Hash) *types.Header {
-	return self.hc.GetHeader(hash)
+func (self *BlockChain) GetHeaderByHash(hash common.Hash) *types.Header {
+	return self.hc.GetHeaderByHash(hash)
 }
 
 // HasHeader checks if a block header is present in the database or not, caching
diff --git a/core/blockchain_test.go b/core/blockchain_test.go
index 876dd2ba1..a26fe4a1b 100644
--- a/core/blockchain_test.go
+++ b/core/blockchain_test.go
@@ -102,17 +102,17 @@ func testFork(t *testing.T, blockchain *BlockChain, i, n int, full bool, compara
 	var tdPre, tdPost *big.Int
 
 	if full {
-		tdPre = blockchain.GetTd(blockchain.CurrentBlock().Hash())
+		tdPre = blockchain.GetTdByHash(blockchain.CurrentBlock().Hash())
 		if err := testBlockChainImport(blockChainB, blockchain); err != nil {
 			t.Fatalf("failed to import forked block chain: %v", err)
 		}
-		tdPost = blockchain.GetTd(blockChainB[len(blockChainB)-1].Hash())
+		tdPost = blockchain.GetTdByHash(blockChainB[len(blockChainB)-1].Hash())
 	} else {
-		tdPre = blockchain.GetTd(blockchain.CurrentHeader().Hash())
+		tdPre = blockchain.GetTdByHash(blockchain.CurrentHeader().Hash())
 		if err := testHeaderChainImport(headerChainB, blockchain); err != nil {
 			t.Fatalf("failed to import forked header chain: %v", err)
 		}
-		tdPost = blockchain.GetTd(headerChainB[len(headerChainB)-1].Hash())
+		tdPost = blockchain.GetTdByHash(headerChainB[len(headerChainB)-1].Hash())
 	}
 	// Compare the total difficulties of the chains
 	comparator(tdPre, tdPost)
@@ -137,7 +137,7 @@ func testBlockChainImport(chain types.Blocks, blockchain *BlockChain) error {
 			}
 			return err
 		}
-		statedb, err := state.New(blockchain.GetBlock(block.ParentHash()).Root(), blockchain.chainDb)
+		statedb, err := state.New(blockchain.GetBlockByHash(block.ParentHash()).Root(), blockchain.chainDb)
 		if err != nil {
 			return err
 		}
@@ -146,13 +146,13 @@ func testBlockChainImport(chain types.Blocks, blockchain *BlockChain) error {
 			reportBlock(block, err)
 			return err
 		}
-		err = blockchain.Validator().ValidateState(block, blockchain.GetBlock(block.ParentHash()), statedb, receipts, usedGas)
+		err = blockchain.Validator().ValidateState(block, blockchain.GetBlockByHash(block.ParentHash()), statedb, receipts, usedGas)
 		if err != nil {
 			reportBlock(block, err)
 			return err
 		}
 		blockchain.mu.Lock()
-		WriteTd(blockchain.chainDb, block.Hash(), new(big.Int).Add(block.Difficulty(), blockchain.GetTd(block.ParentHash())))
+		WriteTd(blockchain.chainDb, block.Hash(), block.NumberU64(), new(big.Int).Add(block.Difficulty(), blockchain.GetTdByHash(block.ParentHash())))
 		WriteBlock(blockchain.chainDb, block)
 		statedb.Commit()
 		blockchain.mu.Unlock()
@@ -165,12 +165,12 @@ func testBlockChainImport(chain types.Blocks, blockchain *BlockChain) error {
 func testHeaderChainImport(chain []*types.Header, blockchain *BlockChain) error {
 	for _, header := range chain {
 		// Try and validate the header
-		if err := blockchain.Validator().ValidateHeader(header, blockchain.GetHeader(header.ParentHash), false); err != nil {
+		if err := blockchain.Validator().ValidateHeader(header, blockchain.GetHeaderByHash(header.ParentHash), false); err != nil {
 			return err
 		}
 		// Manually insert the header into the database, but don't reorganise (allows subsequent testing)
 		blockchain.mu.Lock()
-		WriteTd(blockchain.chainDb, header.Hash(), new(big.Int).Add(header.Difficulty, blockchain.GetTd(header.ParentHash)))
+		WriteTd(blockchain.chainDb, header.Hash(), header.Number.Uint64(), new(big.Int).Add(header.Difficulty, blockchain.GetTdByHash(header.ParentHash)))
 		WriteHeader(blockchain.chainDb, header)
 		blockchain.mu.Unlock()
 	}
@@ -543,11 +543,11 @@ func testReorg(t *testing.T, first, second []int, td int64, full bool) {
 	// Make sure the chain total difficulty is the correct one
 	want := new(big.Int).Add(genesis.Difficulty(), big.NewInt(td))
 	if full {
-		if have := bc.GetTd(bc.CurrentBlock().Hash()); have.Cmp(want) != 0 {
+		if have := bc.GetTdByHash(bc.CurrentBlock().Hash()); have.Cmp(want) != 0 {
 			t.Errorf("total difficulty mismatch: have %v, want %v", have, want)
 		}
 	} else {
-		if have := bc.GetTd(bc.CurrentHeader().Hash()); have.Cmp(want) != 0 {
+		if have := bc.GetTdByHash(bc.CurrentHeader().Hash()); have.Cmp(want) != 0 {
 			t.Errorf("total difficulty mismatch: have %v, want %v", have, want)
 		}
 	}
@@ -758,20 +758,20 @@ func TestFastVsFullChains(t *testing.T) {
 	for i := 0; i < len(blocks); i++ {
 		num, hash := blocks[i].NumberU64(), blocks[i].Hash()
 
-		if ftd, atd := fast.GetTd(hash), archive.GetTd(hash); ftd.Cmp(atd) != 0 {
+		if ftd, atd := fast.GetTdByHash(hash), archive.GetTdByHash(hash); ftd.Cmp(atd) != 0 {
 			t.Errorf("block #%d [%x]: td mismatch: have %v, want %v", num, hash, ftd, atd)
 		}
-		if fheader, aheader := fast.GetHeader(hash), archive.GetHeader(hash); fheader.Hash() != aheader.Hash() {
+		if fheader, aheader := fast.GetHeaderByHash(hash), archive.GetHeaderByHash(hash); fheader.Hash() != aheader.Hash() {
 			t.Errorf("block #%d [%x]: header mismatch: have %v, want %v", num, hash, fheader, aheader)
 		}
-		if fblock, ablock := fast.GetBlock(hash), archive.GetBlock(hash); fblock.Hash() != ablock.Hash() {
+		if fblock, ablock := fast.GetBlockByHash(hash), archive.GetBlockByHash(hash); fblock.Hash() != ablock.Hash() {
 			t.Errorf("block #%d [%x]: block mismatch: have %v, want %v", num, hash, fblock, ablock)
 		} else if types.DeriveSha(fblock.Transactions()) != types.DeriveSha(ablock.Transactions()) {
 			t.Errorf("block #%d [%x]: transactions mismatch: have %v, want %v", num, hash, fblock.Transactions(), ablock.Transactions())
 		} else if types.CalcUncleHash(fblock.Uncles()) != types.CalcUncleHash(ablock.Uncles()) {
 			t.Errorf("block #%d [%x]: uncles mismatch: have %v, want %v", num, hash, fblock.Uncles(), ablock.Uncles())
 		}
-		if freceipts, areceipts := GetBlockReceipts(fastDb, hash), GetBlockReceipts(archiveDb, hash); types.DeriveSha(freceipts) != types.DeriveSha(areceipts) {
+		if freceipts, areceipts := GetBlockReceipts(fastDb, hash, GetBlockNumber(fastDb, hash)), GetBlockReceipts(archiveDb, hash, GetBlockNumber(archiveDb, hash)); types.DeriveSha(freceipts) != types.DeriveSha(areceipts) {
 			t.Errorf("block #%d [%x]: receipts mismatch: have %v, want %v", num, hash, freceipts, areceipts)
 		}
 	}
diff --git a/core/database_util.go b/core/database_util.go
index 3ba80062c..1529d7369 100644
--- a/core/database_util.go
+++ b/core/database_util.go
@@ -36,34 +36,72 @@ var (
 	headBlockKey  = []byte("LastBlock")
 	headFastKey   = []byte("LastFast")
 
-	blockPrefix    = []byte("block-")
-	blockNumPrefix = []byte("block-num-")
+	headerPrefix        = []byte("h") // headerPrefix + num (uint64 big endian) + hash -> header
+	tdSuffix            = []byte("t") // headerPrefix + num (uint64 big endian) + hash + tdSuffix -> td
+	numSuffix           = []byte("n") // headerPrefix + num (uint64 big endian) + numSuffix -> hash
+	blockHashPrefix     = []byte("H") // blockHashPrefix + hash -> num (uint64 big endian)
+	bodyPrefix          = []byte("b") // bodyPrefix + num (uint64 big endian) + hash -> block body
+	blockReceiptsPrefix = []byte("r") // blockReceiptsPrefix + num (uint64 big endian) + hash -> block receipts
 
-	headerSuffix = []byte("-header")
-	bodySuffix   = []byte("-body")
-	tdSuffix     = []byte("-td")
-
-	txMetaSuffix        = []byte{0x01}
-	receiptsPrefix      = []byte("receipts-")
-	blockReceiptsPrefix = []byte("receipts-block-")
+	txMetaSuffix   = []byte{0x01}
+	receiptsPrefix = []byte("receipts-")
 
 	mipmapPre    = []byte("mipmap-log-bloom-")
 	MIPMapLevels = []uint64{1000000, 500000, 100000, 50000, 1000}
 
-	blockHashPrefix = []byte("block-hash-") // [deprecated by the header/block split, remove eventually]
-
 	configPrefix = []byte("ethereum-config-") // config prefix for the db
+
+	// used by old (non-sequential keys) db, now only used for conversion
+	oldBlockPrefix         = []byte("block-")
+	oldHeaderSuffix        = []byte("-header")
+	oldTdSuffix            = []byte("-td") // headerPrefix + num (uint64 big endian) + hash + tdSuffix -> td
+	oldBodySuffix          = []byte("-body")
+	oldBlockNumPrefix      = []byte("block-num-")
+	oldBlockReceiptsPrefix = []byte("receipts-block-")
+	oldBlockHashPrefix     = []byte("block-hash-") // [deprecated by the header/block split, remove eventually]
 )
 
+// encodeBlockNumber encodes a block number as big endian uint64
+func encodeBlockNumber(number uint64) []byte {
+	enc := make([]byte, 8)
+	binary.BigEndian.PutUint64(enc, number)
+	return enc
+}
+
 // GetCanonicalHash retrieves a hash assigned to a canonical block number.
 func GetCanonicalHash(db ethdb.Database, number uint64) common.Hash {
-	data, _ := db.Get(append(blockNumPrefix, big.NewInt(int64(number)).Bytes()...))
+	data, _ := db.Get(append(append(headerPrefix, encodeBlockNumber(number)...), numSuffix...))
 	if len(data) == 0 {
-		return common.Hash{}
+		data, _ = db.Get(append(oldBlockNumPrefix, big.NewInt(int64(number)).Bytes()...))
+		if len(data) == 0 {
+			return common.Hash{}
+		}
 	}
 	return common.BytesToHash(data)
 }
 
+// missingNumber is returned by GetBlockNumber if no header with the
+// given block hash has been stored in the database
+const missingNumber = uint64(0xffffffffffffffff)
+
+// GetBlockNumber returns the block number assigned to a block hash
+// if the corresponding header is present in the database
+func GetBlockNumber(db ethdb.Database, hash common.Hash) uint64 {
+	data, _ := db.Get(append(blockHashPrefix, hash.Bytes()...))
+	if len(data) != 8 {
+		data, _ := db.Get(append(append(oldBlockPrefix, hash.Bytes()...), oldHeaderSuffix...))
+		if len(data) == 0 {
+			return missingNumber
+		}
+		header := new(types.Header)
+		if err := rlp.Decode(bytes.NewReader(data), header); err != nil {
+			glog.Fatalf("failed to decode block header: %v", err)
+		}
+		return header.Number.Uint64()
+	}
+	return binary.BigEndian.Uint64(data)
+}
+
 // GetHeadHeaderHash retrieves the hash of the current canonical head block's
 // header. The difference between this and GetHeadBlockHash is that whereas the
 // last block hash is only updated upon a full block import, the last header
@@ -100,15 +138,18 @@ func GetHeadFastBlockHash(db ethdb.Database) common.Hash {
 
 // GetHeaderRLP retrieves a block header in its raw RLP database encoding, or nil
 // if the header's not found.
-func GetHeaderRLP(db ethdb.Database, hash common.Hash) rlp.RawValue {
-	data, _ := db.Get(append(append(blockPrefix, hash[:]...), headerSuffix...))
+func GetHeaderRLP(db ethdb.Database, hash common.Hash, number uint64) rlp.RawValue {
+	data, _ := db.Get(append(append(headerPrefix, encodeBlockNumber(number)...), hash.Bytes()...))
+	if len(data) == 0 {
+		data, _ = db.Get(append(append(oldBlockPrefix, hash.Bytes()...), oldHeaderSuffix...))
+	}
 	return data
 }
 
 // GetHeader retrieves the block header corresponding to the hash, nil if none
 // found.
-func GetHeader(db ethdb.Database, hash common.Hash) *types.Header {
-	data := GetHeaderRLP(db, hash)
+func GetHeader(db ethdb.Database, hash common.Hash, number uint64) *types.Header {
+	data := GetHeaderRLP(db, hash, number)
 	if len(data) == 0 {
 		return nil
 	}
@@ -121,15 +162,18 @@ func GetHeader(db ethdb.Database, hash common.Hash) *types.Header {
 }
 
 // GetBodyRLP retrieves the block body (transactions and uncles) in RLP encoding.
-func GetBodyRLP(db ethdb.Database, hash common.Hash) rlp.RawValue {
-	data, _ := db.Get(append(append(blockPrefix, hash[:]...), bodySuffix...))
+func GetBodyRLP(db ethdb.Database, hash common.Hash, number uint64) rlp.RawValue {
+	data, _ := db.Get(append(append(bodyPrefix, encodeBlockNumber(number)...), hash.Bytes()...))
+	if len(data) == 0 {
+		data, _ = db.Get(append(append(oldBlockPrefix, hash.Bytes()...), oldBodySuffix...))
+	}
 	return data
 }
 
 // GetBody retrieves the block body (transactons, uncles) corresponding to the
 // hash, nil if none found.
-func GetBody(db ethdb.Database, hash common.Hash) *types.Body {
-	data := GetBodyRLP(db, hash)
+func GetBody(db ethdb.Database, hash common.Hash, number uint64) *types.Body {
+	data := GetBodyRLP(db, hash, number)
 	if len(data) == 0 {
 		return nil
 	}
@@ -143,10 +187,13 @@ func GetBody(db ethdb.Database, hash common.Hash) *types.Body {
 
 // GetTd retrieves a block's total difficulty corresponding to the hash, nil if
 // none found.
-func GetTd(db ethdb.Database, hash common.Hash) *big.Int {
-	data, _ := db.Get(append(append(blockPrefix, hash.Bytes()...), tdSuffix...))
+func GetTd(db ethdb.Database, hash common.Hash, number uint64) *big.Int {
+	data, _ := db.Get(append(append(append(headerPrefix, encodeBlockNumber(number)...), hash[:]...), tdSuffix...))
 	if len(data) == 0 {
-		return nil
+		data, _ = db.Get(append(append(oldBlockPrefix, hash.Bytes()...), oldTdSuffix...))
+		if len(data) == 0 {
+			return nil
+		}
 	}
 	td := new(big.Int)
 	if err := rlp.Decode(bytes.NewReader(data), td); err != nil {
@@ -158,13 +205,13 @@ func GetTd(db ethdb.Database, hash common.Hash) *big.Int {
 
 // GetBlock retrieves an entire block corresponding to the hash, assembling it
 // back from the stored header and body.
-func GetBlock(db ethdb.Database, hash common.Hash) *types.Block {
+func GetBlock(db ethdb.Database, hash common.Hash, number uint64) *types.Block {
 	// Retrieve the block header and body contents
-	header := GetHeader(db, hash)
+	header := GetHeader(db, hash, number)
 	if header == nil {
 		return nil
 	}
-	body := GetBody(db, hash)
+	body := GetBody(db, hash, number)
 	if body == nil {
 		return nil
 	}
@@ -174,10 +221,13 @@ func GetBlock(db ethdb.Database, hash common.Hash) *types.Block {
 
 // GetBlockReceipts retrieves the receipts generated by the transactions included
 // in a block given by its hash.
-func GetBlockReceipts(db ethdb.Database, hash common.Hash) types.Receipts {
-	data, _ := db.Get(append(blockReceiptsPrefix, hash[:]...))
+func GetBlockReceipts(db ethdb.Database, hash common.Hash, number uint64) types.Receipts {
+	data, _ := db.Get(append(append(blockReceiptsPrefix, encodeBlockNumber(number)...), hash[:]...))
 	if len(data) == 0 {
-		return nil
+		data, _ = db.Get(append(oldBlockReceiptsPrefix, hash.Bytes()...))
+		if len(data) == 0 {
+			return nil
+		}
 	}
 	storageReceipts := []*types.ReceiptForStorage{}
 	if err := rlp.DecodeBytes(data, &storageReceipts); err != nil {
@@ -235,10 +285,9 @@ func GetReceipt(db ethdb.Database, txHash common.Hash) *types.Receipt {
 
 // WriteCanonicalHash stores the canonical hash for the given block number.
 func WriteCanonicalHash(db ethdb.Database, hash common.Hash, number uint64) error {
-	key := append(blockNumPrefix, big.NewInt(int64(number)).Bytes()...)
+	key := append(append(headerPrefix, encodeBlockNumber(number)...), numSuffix...)
 	if err := db.Put(key, hash.Bytes()); err != nil {
 		glog.Fatalf("failed to store number to hash mapping into database: %v", err)
-		return err
 	}
 	return nil
 }
@@ -247,7 +296,6 @@ func WriteCanonicalHash(db ethdb.Database, hash common.Hash, number uint64) erro
 func WriteHeadHeaderHash(db ethdb.Database, hash common.Hash) error {
 	if err := db.Put(headHeaderKey, hash.Bytes()); err != nil {
 		glog.Fatalf("failed to store last header's hash into database: %v", err)
-		return err
 	}
 	return nil
 }
@@ -256,7 +304,6 @@ func WriteHeadHeaderHash(db ethdb.Database, hash common.Hash) error {
 func WriteHeadBlockHash(db ethdb.Database, hash common.Hash) error {
 	if err := db.Put(headBlockKey, hash.Bytes()); err != nil {
 		glog.Fatalf("failed to store last block's hash into database: %v", err)
-		return err
 	}
 	return nil
 }
@@ -265,7 +312,6 @@ func WriteHeadBlockHash(db ethdb.Database, hash common.Hash) error {
 func WriteHeadFastBlockHash(db ethdb.Database, hash common.Hash) error {
 	if err := db.Put(headFastKey, hash.Bytes()); err != nil {
 		glog.Fatalf("failed to store last fast block's hash into database: %v", err)
-		return err
 	}
 	return nil
 }
@@ -276,40 +322,44 @@ func WriteHeader(db ethdb.Database, header *types.Header) error {
 	if err != nil {
 		return err
 	}
-	key := append(append(blockPrefix, header.Hash().Bytes()...), headerSuffix...)
+	hash := header.Hash().Bytes()
+	num := header.Number.Uint64()
+	encNum := encodeBlockNumber(num)
+	key := append(blockHashPrefix, hash...)
+	if err := db.Put(key, encNum); err != nil {
+		glog.Fatalf("failed to store hash to number mapping into database: %v", err)
+	}
+	key = append(append(headerPrefix, encNum...), hash...)
 	if err := db.Put(key, data); err != nil {
 		glog.Fatalf("failed to store header into database: %v", err)
-		return err
 	}
-	glog.V(logger.Debug).Infof("stored header #%v [%x…]", header.Number, header.Hash().Bytes()[:4])
+	glog.V(logger.Debug).Infof("stored header #%v [%x…]", header.Number, hash[:4])
 	return nil
 }
 
 // WriteBody serializes the body of a block into the database.
-func WriteBody(db ethdb.Database, hash common.Hash, body *types.Body) error {
+func WriteBody(db ethdb.Database, hash common.Hash, number uint64, body *types.Body) error {
 	data, err := rlp.EncodeToBytes(body)
 	if err != nil {
 		return err
 	}
-	key := append(append(blockPrefix, hash.Bytes()...), bodySuffix...)
+	key := append(append(bodyPrefix, encodeBlockNumber(number)...), hash.Bytes()...)
 	if err := db.Put(key, data); err != nil {
 		glog.Fatalf("failed to store block body into database: %v", err)
-		return err
 	}
 	glog.V(logger.Debug).Infof("stored block body [%x…]", hash.Bytes()[:4])
 	return nil
 }
 
 // WriteTd serializes the total difficulty of a block into the database.
-func WriteTd(db ethdb.Database, hash common.Hash, td *big.Int) error {
+func WriteTd(db ethdb.Database, hash common.Hash, number uint64, td *big.Int) error {
 	data, err := rlp.EncodeToBytes(td)
 	if err != nil {
 		return err
 	}
-	key := append(append(blockPrefix, hash.Bytes()...), tdSuffix...)
+	key := append(append(append(headerPrefix, encodeBlockNumber(number)...), hash.Bytes()...), tdSuffix...)
 	if err := db.Put(key, data); err != nil {
 		glog.Fatalf("failed to store block total difficulty into database: %v", err)
-		return err
 	}
 	glog.V(logger.Debug).Infof("stored block total difficulty [%x…]: %v", hash.Bytes()[:4], td)
 	return nil
@@ -318,7 +368,7 @@ func WriteTd(db ethdb.Database, hash common.Hash, td *big.Int) error {
 // WriteBlock serializes a block into the database, header and body separately.
 func WriteBlock(db ethdb.Database, block *types.Block) error {
 	// Store the body first to retain database consistency
-	if err := WriteBody(db, block.Hash(), block.Body()); err != nil {
+	if err := WriteBody(db, block.Hash(), block.NumberU64(), block.Body()); err != nil {
 		return err
 	}
 	// Store the header too, signaling full block ownership
@@ -331,7 +381,7 @@ func WriteBlock(db ethdb.Database, block *types.Block) error {
 // WriteBlockReceipts stores all the transaction receipts belonging to a block
 // as a single receipt slice. This is used during chain reorganisations for
 // rescheduling dropped transactions.
-func WriteBlockReceipts(db ethdb.Database, hash common.Hash, receipts types.Receipts) error {
+func WriteBlockReceipts(db ethdb.Database, hash common.Hash, number uint64, receipts types.Receipts) error {
 	// Convert the receipts into their storage form and serialize them
 	storageReceipts := make([]*types.ReceiptForStorage, len(receipts))
 	for i, receipt := range receipts {
@@ -342,9 +392,9 @@ func WriteBlockReceipts(db ethdb.Database, hash common.Hash, receipts types.Rece
 		return err
 	}
 	// Store the flattened receipt slice
-	if err := db.Put(append(blockReceiptsPrefix, hash.Bytes()...), bytes); err != nil {
+	key := append(append(blockReceiptsPrefix, encodeBlockNumber(number)...), hash.Bytes()...)
+	if err := db.Put(key, bytes); err != nil {
 		glog.Fatalf("failed to store block receipts into database: %v", err)
-		return err
 	}
 	glog.V(logger.Debug).Infof("stored block receipts [%x…]", hash.Bytes()[:4])
 	return nil
@@ -388,7 +438,6 @@ func WriteTransactions(db ethdb.Database, block *types.Block) error {
 	// Write the scheduled data into the database
 	if err := batch.Write(); err != nil {
 		glog.Fatalf("failed to store transactions into database: %v", err)
-		return err
 	}
 	return nil
 }
@@ -411,42 +460,42 @@ func WriteReceipts(db ethdb.Database, receipts types.Receipts) error {
 	// Write the scheduled data into the database
 	if err := batch.Write(); err != nil {
 		glog.Fatalf("failed to store receipts into database: %v", err)
-		return err
 	}
 	return nil
 }
 
 // DeleteCanonicalHash removes the number to hash canonical mapping.
 func DeleteCanonicalHash(db ethdb.Database, number uint64) {
-	db.Delete(append(blockNumPrefix, big.NewInt(int64(number)).Bytes()...))
+	db.Delete(append(append(headerPrefix, encodeBlockNumber(number)...), numSuffix...))
 }
 
 // DeleteHeader removes all block header data associated with a hash.
-func DeleteHeader(db ethdb.Database, hash common.Hash) {
-	db.Delete(append(append(blockPrefix, hash.Bytes()...), headerSuffix...))
+func DeleteHeader(db ethdb.Database, hash common.Hash, number uint64) {
+	db.Delete(append(blockHashPrefix, hash.Bytes()...))
+	db.Delete(append(append(headerPrefix, encodeBlockNumber(number)...), hash.Bytes()...))
 }
 
 // DeleteBody removes all block body data associated with a hash.
-func DeleteBody(db ethdb.Database, hash common.Hash) {
-	db.Delete(append(append(blockPrefix, hash.Bytes()...), bodySuffix...))
+func DeleteBody(db ethdb.Database, hash common.Hash, number uint64) {
+	db.Delete(append(append(bodyPrefix, encodeBlockNumber(number)...), hash.Bytes()...))
 }
 
 // DeleteTd removes all block total difficulty data associated with a hash.
-func DeleteTd(db ethdb.Database, hash common.Hash) {
-	db.Delete(append(append(blockPrefix, hash.Bytes()...), tdSuffix...))
+func DeleteTd(db ethdb.Database, hash common.Hash, number uint64) {
+	db.Delete(append(append(append(headerPrefix, encodeBlockNumber(number)...), hash.Bytes()...), tdSuffix...))
 }
 
 // DeleteBlock removes all block data associated with a hash.
-func DeleteBlock(db ethdb.Database, hash common.Hash) {
-	DeleteBlockReceipts(db, hash)
-	DeleteHeader(db, hash)
-	DeleteBody(db, hash)
-	DeleteTd(db, hash)
+func DeleteBlock(db ethdb.Database, hash common.Hash, number uint64) {
+	DeleteBlockReceipts(db, hash, number)
+	DeleteHeader(db, hash, number)
+	DeleteBody(db, hash, number)
+	DeleteTd(db, hash, number)
 }
 
 // DeleteBlockReceipts removes all receipt data associated with a block hash.
-func DeleteBlockReceipts(db ethdb.Database, hash common.Hash) {
-	db.Delete(append(blockReceiptsPrefix, hash.Bytes()...))
+func DeleteBlockReceipts(db ethdb.Database, hash common.Hash, number uint64) {
+	db.Delete(append(append(blockReceiptsPrefix, encodeBlockNumber(number)...), hash.Bytes()...))
 }
 
 // DeleteTransaction removes all transaction data associated with a hash.
@@ -466,7 +515,7 @@ func DeleteReceipt(db ethdb.Database, hash common.Hash) {
 // access the old combined block representation. It will be dropped after the
 // network transitions to eth/63.
 func GetBlockByHashOld(db ethdb.Database, hash common.Hash) *types.Block {
-	data, _ := db.Get(append(blockHashPrefix, hash[:]...))
+	data, _ := db.Get(append(oldBlockHashPrefix, hash[:]...))
 	if len(data) == 0 {
 		return nil
 	}
diff --git a/core/database_util_test.go b/core/database_util_test.go
index 9ef787624..6c19f78c8 100644
--- a/core/database_util_test.go
+++ b/core/database_util_test.go
@@ -89,20 +89,20 @@ func TestHeaderStorage(t *testing.T) {
 	db, _ := ethdb.NewMemDatabase()
 
 	// Create a test header to move around the database and make sure it's really new
-	header := &types.Header{Extra: []byte("test header")}
-	if entry := GetHeader(db, header.Hash()); entry != nil {
+	header := &types.Header{Number: big.NewInt(42), Extra: []byte("test header")}
+	if entry := GetHeader(db, header.Hash(), header.Number.Uint64()); entry != nil {
 		t.Fatalf("Non existent header returned: %v", entry)
 	}
 	// Write and verify the header in the database
 	if err := WriteHeader(db, header); err != nil {
 		t.Fatalf("Failed to write header into database: %v", err)
 	}
-	if entry := GetHeader(db, header.Hash()); entry == nil {
+	if entry := GetHeader(db, header.Hash(), header.Number.Uint64()); entry == nil {
 		t.Fatalf("Stored header not found")
 	} else if entry.Hash() != header.Hash() {
 		t.Fatalf("Retrieved header mismatch: have %v, want %v", entry, header)
 	}
-	if entry := GetHeaderRLP(db, header.Hash()); entry == nil {
+	if entry := GetHeaderRLP(db, header.Hash(), header.Number.Uint64()); entry == nil {
 		t.Fatalf("Stored header RLP not found")
 	} else {
 		hasher := sha3.NewKeccak256()
@@ -113,8 +113,8 @@ func TestHeaderStorage(t *testing.T) {
 		}
 	}
 	// Delete the header and verify the execution
-	DeleteHeader(db, header.Hash())
-	if entry := GetHeader(db, header.Hash()); entry != nil {
+	DeleteHeader(db, header.Hash(), header.Number.Uint64())
+	if entry := GetHeader(db, header.Hash(), header.Number.Uint64()); entry != nil {
 		t.Fatalf("Deleted header returned: %v", entry)
 	}
 }
@@ -130,19 +130,19 @@ func TestBodyStorage(t *testing.T) {
 	rlp.Encode(hasher, body)
 	hash := common.BytesToHash(hasher.Sum(nil))
 
-	if entry := GetBody(db, hash); entry != nil {
+	if entry := GetBody(db, hash, 0); entry != nil {
 		t.Fatalf("Non existent body returned: %v", entry)
 	}
 	// Write and verify the body in the database
-	if err := WriteBody(db, hash, body); err != nil {
+	if err := WriteBody(db, hash, 0, body); err != nil {
 		t.Fatalf("Failed to write body into database: %v", err)
 	}
-	if entry := GetBody(db, hash); entry == nil {
+	if entry := GetBody(db, hash, 0); entry == nil {
 		t.Fatalf("Stored body not found")
 	} else if types.DeriveSha(types.Transactions(entry.Transactions)) != types.DeriveSha(types.Transactions(body.Transactions)) || types.CalcUncleHash(entry.Uncles) != types.CalcUncleHash(body.Uncles) {
 		t.Fatalf("Retrieved body mismatch: have %v, want %v", entry, body)
 	}
-	if entry := GetBodyRLP(db, hash); entry == nil {
+	if entry := GetBodyRLP(db, hash, 0); entry == nil {
 		t.Fatalf("Stored body RLP not found")
 	} else {
 		hasher := sha3.NewKeccak256()
@@ -153,8 +153,8 @@ func TestBodyStorage(t *testing.T) {
 		}
 	}
 	// Delete the body and verify the execution
-	DeleteBody(db, hash)
-	if entry := GetBody(db, hash); entry != nil {
+	DeleteBody(db, hash, 0)
+	if entry := GetBody(db, hash, 0); entry != nil {
 		t.Fatalf("Deleted body returned: %v", entry)
 	}
 }
@@ -170,43 +170,43 @@ func TestBlockStorage(t *testing.T) {
 		TxHash:      types.EmptyRootHash,
 		ReceiptHash: types.EmptyRootHash,
 	})
-	if entry := GetBlock(db, block.Hash()); entry != nil {
+	if entry := GetBlock(db, block.Hash(), block.NumberU64()); entry != nil {
 		t.Fatalf("Non existent block returned: %v", entry)
 	}
-	if entry := GetHeader(db, block.Hash()); entry != nil {
+	if entry := GetHeader(db, block.Hash(), block.NumberU64()); entry != nil {
 		t.Fatalf("Non existent header returned: %v", entry)
 	}
-	if entry := GetBody(db, block.Hash()); entry != nil {
+	if entry := GetBody(db, block.Hash(), block.NumberU64()); entry != nil {
 		t.Fatalf("Non existent body returned: %v", entry)
 	}
 	// Write and verify the block in the database
 	if err := WriteBlock(db, block); err != nil {
 		t.Fatalf("Failed to write block into database: %v", err)
 	}
-	if entry := GetBlock(db, block.Hash()); entry == nil {
+	if entry := GetBlock(db, block.Hash(), block.NumberU64()); entry == nil {
 		t.Fatalf("Stored block not found")
 	} else if entry.Hash() != block.Hash() {
 		t.Fatalf("Retrieved block mismatch: have %v, want %v", entry, block)
 	}
-	if entry := GetHeader(db, block.Hash()); entry == nil {
+	if entry := GetHeader(db, block.Hash(), block.NumberU64()); entry == nil {
 		t.Fatalf("Stored header not found")
 	} else if entry.Hash() != block.Header().Hash() {
 		t.Fatalf("Retrieved header mismatch: have %v, want %v", entry, block.Header())
 	}
-	if entry := GetBody(db, block.Hash()); entry == nil {
+	if entry := GetBody(db, block.Hash(), block.NumberU64()); entry == nil {
 		t.Fatalf("Stored body not found")
 	} else if types.DeriveSha(types.Transactions(entry.Transactions)) != types.DeriveSha(block.Transactions()) || types.CalcUncleHash(entry.Uncles) != types.CalcUncleHash(block.Uncles()) {
 		t.Fatalf("Retrieved body mismatch: have %v, want %v", entry, block.Body())
 	}
 	// Delete the block and verify the execution
-	DeleteBlock(db, block.Hash())
-	if entry := GetBlock(db, block.Hash()); entry != nil {
+	DeleteBlock(db, block.Hash(), block.NumberU64())
+	if entry := GetBlock(db, block.Hash(), block.NumberU64()); entry != nil {
 		t.Fatalf("Deleted block returned: %v", entry)
 	}
-	if entry := GetHeader(db, block.Hash()); entry != nil {
+	if entry := GetHeader(db, block.Hash(), block.NumberU64()); entry != nil {
 		t.Fatalf("Deleted header returned: %v", entry)
 	}
-	if entry := GetBody(db, block.Hash()); entry != nil {
+	if entry := GetBody(db, block.Hash(), block.NumberU64()); entry != nil {
 		t.Fatalf("Deleted body returned: %v", entry)
 	}
 }
@@ -224,28 +224,28 @@ func TestPartialBlockStorage(t *testing.T) {
 	if err := WriteHeader(db, block.Header()); err != nil {
 		t.Fatalf("Failed to write header into database: %v", err)
 	}
-	if entry := GetBlock(db, block.Hash()); entry != nil {
+	if entry := GetBlock(db, block.Hash(), block.NumberU64()); entry != nil {
 		t.Fatalf("Non existent block returned: %v", entry)
 	}
-	DeleteHeader(db, block.Hash())
+	DeleteHeader(db, block.Hash(), block.NumberU64())
 
 	// Store a body and check that it's not recognized as a block
-	if err := WriteBody(db, block.Hash(), block.Body()); err != nil {
+	if err := WriteBody(db, block.Hash(), block.NumberU64(), block.Body()); err != nil {
 		t.Fatalf("Failed to write body into database: %v", err)
 	}
-	if entry := GetBlock(db, block.Hash()); entry != nil {
+	if entry := GetBlock(db, block.Hash(), block.NumberU64()); entry != nil {
 		t.Fatalf("Non existent block returned: %v", entry)
 	}
-	DeleteBody(db, block.Hash())
+	DeleteBody(db, block.Hash(), block.NumberU64())
 
 	// Store a header and a body separately and check reassembly
 	if err := WriteHeader(db, block.Header()); err != nil {
 		t.Fatalf("Failed to write header into database: %v", err)
 	}
-	if err := WriteBody(db, block.Hash(), block.Body()); err != nil {
+	if err := WriteBody(db, block.Hash(), block.NumberU64(), block.Body()); err != nil {
 		t.Fatalf("Failed to write body into database: %v", err)
 	}
-	if entry := GetBlock(db, block.Hash()); entry == nil {
+	if entry := GetBlock(db, block.Hash(), block.NumberU64()); entry == nil {
 		t.Fatalf("Stored block not found")
 	} else if entry.Hash() != block.Hash() {
 		t.Fatalf("Retrieved block mismatch: have %v, want %v", entry, block)
@@ -258,21 +258,21 @@ func TestTdStorage(t *testing.T) {
 
 	// Create a test TD to move around the database and make sure it's really new
 	hash, td := common.Hash{}, big.NewInt(314)
-	if entry := GetTd(db, hash); entry != nil {
+	if entry := GetTd(db, hash, 0); entry != nil {
 		t.Fatalf("Non existent TD returned: %v", entry)
 	}
 	// Write and verify the TD in the database
-	if err := WriteTd(db, hash, td); err != nil {
+	if err := WriteTd(db, hash, 0, td); err != nil {
 		t.Fatalf("Failed to write TD into database: %v", err)
 	}
-	if entry := GetTd(db, hash); entry == nil {
+	if entry := GetTd(db, hash, 0); entry == nil {
 		t.Fatalf("Stored TD not found")
 	} else if entry.Cmp(td) != 0 {
 		t.Fatalf("Retrieved TD mismatch: have %v, want %v", entry, td)
 	}
 	// Delete the TD and verify the execution
-	DeleteTd(db, hash)
-	if entry := GetTd(db, hash); entry != nil {
+	DeleteTd(db, hash, 0)
+	if entry := GetTd(db, hash, 0); entry != nil {
 		t.Fatalf("Deleted TD returned: %v", entry)
 	}
 }
@@ -473,14 +473,14 @@ func TestBlockReceiptStorage(t *testing.T) {
 
 	// Check that no receipt entries are in a pristine database
 	hash := common.BytesToHash([]byte{0x03, 0x14})
-	if rs := GetBlockReceipts(db, hash); len(rs) != 0 {
+	if rs := GetBlockReceipts(db, hash, 0); len(rs) != 0 {
 		t.Fatalf("non existent receipts returned: %v", rs)
 	}
 	// Insert the receipt slice into the database and check presence
-	if err := WriteBlockReceipts(db, hash, receipts); err != nil {
+	if err := WriteBlockReceipts(db, hash, 0, receipts); err != nil {
 		t.Fatalf("failed to write block receipts: %v", err)
 	}
-	if rs := GetBlockReceipts(db, hash); len(rs) == 0 {
+	if rs := GetBlockReceipts(db, hash, 0); len(rs) == 0 {
 		t.Fatalf("no receipts returned")
 	} else {
 		for i := 0; i < len(receipts); i++ {
@@ -493,8 +493,8 @@ func TestBlockReceiptStorage(t *testing.T) {
 		}
 	}
 	// Delete the receipt slice and check purge
-	DeleteBlockReceipts(db, hash)
-	if rs := GetBlockReceipts(db, hash); len(rs) != 0 {
+	DeleteBlockReceipts(db, hash, 0)
+	if rs := GetBlockReceipts(db, hash, 0); len(rs) != 0 {
 		t.Fatalf("deleted receipts returned: %v", rs)
 	}
 }
@@ -597,7 +597,7 @@ func TestMipmapChain(t *testing.T) {
 		if err := WriteHeadBlockHash(db, block.Hash()); err != nil {
 			t.Fatalf("failed to insert block number: %v", err)
 		}
-		if err := WriteBlockReceipts(db, block.Hash(), receipts[i]); err != nil {
+		if err := WriteBlockReceipts(db, block.Hash(), block.NumberU64(), receipts[i]); err != nil {
 			t.Fatal("error writing block receipts:", err)
 		}
 	}
diff --git a/core/genesis.go b/core/genesis.go
index 40d799621..637b63320 100644
--- a/core/genesis.go
+++ b/core/genesis.go
@@ -88,7 +88,7 @@ func WriteGenesisBlock(chainDb ethdb.Database, reader io.Reader) (*types.Block,
 		Root:       root,
 	}, nil, nil, nil)
 
-	if block := GetBlock(chainDb, block.Hash()); block != nil {
+	if block := GetBlock(chainDb, block.Hash(), block.NumberU64()); block != nil {
 		glog.V(logger.Info).Infoln("Genesis block already in chain. Writing canonical number")
 		err := WriteCanonicalHash(chainDb, block.Hash(), block.NumberU64())
 		if err != nil {
@@ -100,13 +100,13 @@ func WriteGenesisBlock(chainDb ethdb.Database, reader io.Reader) (*types.Block,
 	if err := stateBatch.Write(); err != nil {
 		return nil, fmt.Errorf("cannot write state: %v", err)
 	}
-	if err := WriteTd(chainDb, block.Hash(), difficulty); err != nil {
+	if err := WriteTd(chainDb, block.Hash(), block.NumberU64(), difficulty); err != nil {
 		return nil, err
 	}
 	if err := WriteBlock(chainDb, block); err != nil {
 		return nil, err
 	}
-	if err := WriteBlockReceipts(chainDb, block.Hash(), nil); err != nil {
+	if err := WriteBlockReceipts(chainDb, block.Hash(), block.NumberU64(), nil); err != nil {
 		return nil, err
 	}
 	if err := WriteCanonicalHash(chainDb, block.Hash(), block.NumberU64()); err != nil {
diff --git a/core/headerchain.go b/core/headerchain.go
index 5e0fbfb08..f856333a0 100644
--- a/core/headerchain.go
+++ b/core/headerchain.go
@@ -35,6 +35,12 @@ import (
 	"github.com/hashicorp/golang-lru"
 )
 
+const (
+	headerCacheLimit = 512
+	tdCacheLimit     = 1024
+	numberCacheLimit = 2048
+)
+
 // HeaderChain implements the basic block header chain logic that is shared by
 // core.BlockChain and light.LightChain. It is not usable in itself, only as
 // a part of either structure.
@@ -51,6 +57,7 @@ type HeaderChain struct {
 
 	headerCache *lru.Cache // Cache for the most recent block headers
 	tdCache     *lru.Cache // Cache for the most recent block total difficulties
+	numberCache *lru.Cache // Cache for the most recent block numbers
 
 	procInterrupt func() bool
 
@@ -68,6 +75,7 @@ type getHeaderValidatorFn func() HeaderValidator
 func NewHeaderChain(chainDb ethdb.Database, config *ChainConfig, getValidator getHeaderValidatorFn, procInterrupt func() bool) (*HeaderChain, error) {
 	headerCache, _ := lru.New(headerCacheLimit)
 	tdCache, _ := lru.New(tdCacheLimit)
+	numberCache, _ := lru.New(numberCacheLimit)
 
 	// Seed a fast but crypto originating random generator
 	seed, err := crand.Int(crand.Reader, big.NewInt(math.MaxInt64))
@@ -80,6 +88,7 @@ func NewHeaderChain(chainDb ethdb.Database, config *ChainConfig, getValidator ge
 		chainDb:       chainDb,
 		headerCache:   headerCache,
 		tdCache:       tdCache,
+		numberCache:   numberCache,
 		procInterrupt: procInterrupt,
 		rand:          mrand.New(mrand.NewSource(seed.Int64())),
 		getValidator:  getValidator,
@@ -97,7 +106,7 @@ func NewHeaderChain(chainDb ethdb.Database, config *ChainConfig, getValidator ge
 
 	hc.currentHeader = hc.genesisHeader
 	if head := GetHeadBlockHash(chainDb); head != (common.Hash{}) {
-		if chead := hc.GetHeader(head); chead != nil {
+		if chead := hc.GetHeaderByHash(head); chead != nil {
 			hc.currentHeader = chead
 		}
 	}
@@ -106,6 +115,19 @@ func NewHeaderChain(chainDb ethdb.Database, config *ChainConfig, getValidator ge
 	return hc, nil
 }
 
+// GetBlockNumber retrieves the block number belonging to the given hash
+// from the cache or database
+func (hc *HeaderChain) GetBlockNumber(hash common.Hash) uint64 {
+	if cached, ok := hc.numberCache.Get(hash); ok {
+		return cached.(uint64)
+	}
+	number := GetBlockNumber(hc.chainDb, hash)
+	if number != missingNumber {
+		hc.numberCache.Add(hash, number)
+	}
+	return number
+}
+
 // WriteHeader writes a header into the local chain, given that its parent is
 // already known. If the total difficulty of the newly inserted header becomes
 // greater than the current known TD, the canonical chain is re-routed.
@@ -122,11 +144,11 @@ func (hc *HeaderChain) WriteHeader(header *types.Header) (status WriteStatus, er
 		number = header.Number.Uint64()
 	)
 	// Calculate the total difficulty of the header
-	ptd := hc.GetTd(header.ParentHash)
+	ptd := hc.GetTd(header.ParentHash, number-1)
 	if ptd == nil {
 		return NonStatTy, ParentError(header.ParentHash)
 	}
-	localTd := hc.GetTd(hc.currentHeaderHash)
+	localTd := hc.GetTd(hc.currentHeaderHash, hc.currentHeader.Number.Uint64())
 	externTd := new(big.Int).Add(header.Difficulty, ptd)
 
 	// If the total difficulty is higher than our known, add it to the canonical chain
@@ -134,21 +156,25 @@ func (hc *HeaderChain) WriteHeader(header *types.Header) (status WriteStatus, er
 	// Please refer to http://www.cs.cornell.edu/~ie53/publications/btcProcFC.pdf
 	if externTd.Cmp(localTd) > 0 || (externTd.Cmp(localTd) == 0 && mrand.Float64() < 0.5) {
 		// Delete any canonical number assignments above the new head
-		for i := number + 1; GetCanonicalHash(hc.chainDb, i) != (common.Hash{}); i++ {
+		for i := number + 1; ; i++ {
+			hash := GetCanonicalHash(hc.chainDb, i)
+			if hash == (common.Hash{}) {
+				break
+			}
 			DeleteCanonicalHash(hc.chainDb, i)
 		}
 		// Overwrite any stale canonical number assignments
 		var (
 			headHash   = header.ParentHash
-			headHeader = hc.GetHeader(headHash)
-			headNumber = headHeader.Number.Uint64()
+			headNumber = header.Number.Uint64() - 1
+			headHeader = hc.GetHeader(headHash, headNumber)
 		)
 		for GetCanonicalHash(hc.chainDb, headNumber) != headHash {
 			WriteCanonicalHash(hc.chainDb, headHash, headNumber)
 
 			headHash = headHeader.ParentHash
-			headHeader = hc.GetHeader(headHash)
-			headNumber = headHeader.Number.Uint64()
+			headNumber = headHeader.Number.Uint64() - 1
+			headHeader = hc.GetHeader(headHash, headNumber)
 		}
 		// Extend the canonical chain with the new header
 		if err := WriteCanonicalHash(hc.chainDb, hash, number); err != nil {
@@ -164,13 +190,14 @@ func (hc *HeaderChain) WriteHeader(header *types.Header) (status WriteStatus, er
 		status = SideStatTy
 	}
 	// Irrelevant of the canonical status, write the header itself to the database
-	if err := hc.WriteTd(hash, externTd); err != nil {
+	if err := hc.WriteTd(hash, number, externTd); err != nil {
 		glog.Fatalf("failed to write header total difficulty: %v", err)
 	}
 	if err := WriteHeader(hc.chainDb, header); err != nil {
 		glog.Fatalf("failed to write header contents: %v", err)
 	}
 	hc.headerCache.Add(hash, header)
+	hc.numberCache.Add(hash, number)
 
 	return
 }
@@ -239,7 +266,7 @@ func (hc *HeaderChain) InsertHeaderChain(chain []*types.Header, checkFreq int, w
 
 			var err error
 			if index == 0 {
-				err = hc.getValidator().ValidateHeader(header, hc.GetHeader(header.ParentHash), checkPow)
+				err = hc.getValidator().ValidateHeader(header, hc.GetHeader(header.ParentHash, header.Number.Uint64()-1), checkPow)
 			} else {
 				err = hc.getValidator().ValidateHeader(header, chain[index-1], checkPow)
 			}
@@ -300,7 +327,7 @@ func (hc *HeaderChain) InsertHeaderChain(chain []*types.Header, checkFreq int, w
 // hash, fetching towards the genesis block.
 func (hc *HeaderChain) GetBlockHashesFromHash(hash common.Hash, max uint64) []common.Hash {
 	// Get the origin header from which to fetch
-	header := hc.GetHeader(hash)
+	header := hc.GetHeaderByHash(hash)
 	if header == nil {
 		return nil
 	}
@@ -308,7 +335,7 @@ func (hc *HeaderChain) GetBlockHashesFromHash(hash common.Hash, max uint64) []co
 	chain := make([]common.Hash, 0, max)
 	for i := uint64(0); i < max; i++ {
 		next := header.ParentHash
-		if header = hc.GetHeader(next); header == nil {
+		if header = hc.GetHeader(next, header.Number.Uint64()-1); header == nil {
 			break
 		}
 		chain = append(chain, next)
@@ -320,13 +347,13 @@ func (hc *HeaderChain) GetBlockHashesFromHash(hash common.Hash, max uint64) []co
 }
 
 // GetTd retrieves a block's total difficulty in the canonical chain from the
-// database by hash, caching it if found.
-func (hc *HeaderChain) GetTd(hash common.Hash) *big.Int {
+// database by hash and number, caching it if found.
+func (hc *HeaderChain) GetTd(hash common.Hash, number uint64) *big.Int {
 	// Short circuit if the td's already in the cache, retrieve otherwise
 	if cached, ok := hc.tdCache.Get(hash); ok {
 		return cached.(*big.Int)
 	}
-	td := GetTd(hc.chainDb, hash)
+	td := GetTd(hc.chainDb, hash, number)
 	if td == nil {
 		return nil
 	}
@@ -335,24 +362,30 @@ func (hc *HeaderChain) GetTd(hash common.Hash) *big.Int {
 	return td
 }
 
+// GetTdByHash retrieves a block's total difficulty in the canonical chain from the
+// database by hash, caching it if found.
+func (hc *HeaderChain) GetTdByHash(hash common.Hash) *big.Int {
+	return hc.GetTd(hash, hc.GetBlockNumber(hash))
+}
+
 // WriteTd stores a block's total difficulty into the database, also caching it
 // along the way.
-func (hc *HeaderChain) WriteTd(hash common.Hash, td *big.Int) error {
-	if err := WriteTd(hc.chainDb, hash, td); err != nil {
+func (hc *HeaderChain) WriteTd(hash common.Hash, number uint64, td *big.Int) error {
+	if err := WriteTd(hc.chainDb, hash, number, td); err != nil {
 		return err
 	}
 	hc.tdCache.Add(hash, new(big.Int).Set(td))
 	return nil
 }
 
-// GetHeader retrieves a block header from the database by hash, caching it if
-// found.
-func (hc *HeaderChain) GetHeader(hash common.Hash) *types.Header {
+// GetHeader retrieves a block header from the database by hash and number,
+// caching it if found.
+func (hc *HeaderChain) GetHeader(hash common.Hash, number uint64) *types.Header {
 	// Short circuit if the header's already in the cache, retrieve otherwise
 	if header, ok := hc.headerCache.Get(hash); ok {
 		return header.(*types.Header)
 	}
-	header := GetHeader(hc.chainDb, hash)
+	header := GetHeader(hc.chainDb, hash, number)
 	if header == nil {
 		return nil
 	}
@@ -361,10 +394,16 @@ func (hc *HeaderChain) GetHeader(hash common.Hash) *types.Header {
 	return header
 }
 
+// GetHeaderByHash retrieves a block header from the database by hash, caching it if
+// found.
+func (hc *HeaderChain) GetHeaderByHash(hash common.Hash) *types.Header {
+	return hc.GetHeader(hash, hc.GetBlockNumber(hash))
+}
+
 // HasHeader checks if a block header is present in the database or not, caching
 // it if present.
 func (hc *HeaderChain) HasHeader(hash common.Hash) bool {
-	return hc.GetHeader(hash) != nil
+	return hc.GetHeaderByHash(hash) != nil
 }
 
 // GetHeaderByNumber retrieves a block header from the database by number,
@@ -374,7 +413,7 @@ func (hc *HeaderChain) GetHeaderByNumber(number uint64) *types.Header {
 	if hash == (common.Hash{}) {
 		return nil
 	}
-	return hc.GetHeader(hash)
+	return hc.GetHeader(hash, number)
 }
 
 // CurrentHeader retrieves the current head header of the canonical chain. The
@@ -394,7 +433,7 @@ func (hc *HeaderChain) SetCurrentHeader(head *types.Header) {
 
 // DeleteCallback is a callback function that is called by SetHead before
 // each header is deleted.
-type DeleteCallback func(common.Hash)
+type DeleteCallback func(common.Hash, uint64)
 
 // SetHead rewinds the local chain to a new head. Everything above the new head
 // will be deleted and the new one set.
@@ -406,12 +445,13 @@ func (hc *HeaderChain) SetHead(head uint64, delFn DeleteCallback) {
 
 	for hc.currentHeader != nil && hc.currentHeader.Number.Uint64() > head {
 		hash := hc.currentHeader.Hash()
+		num := hc.currentHeader.Number.Uint64()
 		if delFn != nil {
-			delFn(hash)
+			delFn(hash, num)
 		}
-		DeleteHeader(hc.chainDb, hash)
-		DeleteTd(hc.chainDb, hash)
-		hc.currentHeader = hc.GetHeader(hc.currentHeader.ParentHash)
+		DeleteHeader(hc.chainDb, hash, num)
+		DeleteTd(hc.chainDb, hash, num)
+		hc.currentHeader = hc.GetHeader(hc.currentHeader.ParentHash, hc.currentHeader.Number.Uint64()-1)
 	}
 	// Roll back the canonical chain numbering
 	for i := height; i > head; i-- {
@@ -420,6 +460,7 @@ func (hc *HeaderChain) SetHead(head uint64, delFn DeleteCallback) {
 	// Clear out any stale content from the caches
 	hc.headerCache.Purge()
 	hc.tdCache.Purge()
+	hc.numberCache.Purge()
 
 	if hc.currentHeader == nil {
 		hc.currentHeader = hc.genesisHeader
diff --git a/core/vm_env.go b/core/vm_env.go
index f50140c68..599672382 100644
--- a/core/vm_env.go
+++ b/core/vm_env.go
@@ -30,7 +30,7 @@ import (
 // to query for information.
 func GetHashFn(ref common.Hash, chain *BlockChain) func(n uint64) common.Hash {
 	return func(n uint64) common.Hash {
-		for block := chain.GetBlock(ref); block != nil; block = chain.GetBlock(block.ParentHash()) {
+		for block := chain.GetBlockByHash(ref); block != nil; block = chain.GetBlock(block.ParentHash(), block.NumberU64()-1) {
 			if block.NumberU64() == n {
 				return block.Hash()
 			}