diff --git a/cmd/utils/cmd.go b/cmd/utils/cmd.go
index 17c258c6c8..23b10c2d74 100644
--- a/cmd/utils/cmd.go
+++ b/cmd/utils/cmd.go
@@ -164,7 +164,7 @@ func ImportChain(chain *core.BlockChain, fn string) error {
 
 func hasAllBlocks(chain *core.BlockChain, bs []*types.Block) bool {
 	for _, b := range bs {
-		if !chain.HasBlock(b.Hash()) {
+		if !chain.HasBlock(b.Hash(), b.NumberU64()) {
 			return false
 		}
 	}
diff --git a/core/blockchain.go b/core/blockchain.go
index d74b3520b1..25be8d762a 100644
--- a/core/blockchain.go
+++ b/core/blockchain.go
@@ -23,7 +23,6 @@ import (
 	"io"
 	"math/big"
 	mrand "math/rand"
-	"runtime"
 	"sync"
 	"sync/atomic"
 	"time"
@@ -515,10 +514,13 @@ func (bc *BlockChain) GetBodyRLP(hash common.Hash) rlp.RawValue {
 	return body
 }
 
-// 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.GetBlockByHash(hash) != nil
+// HasBlock checks if a block is fully present in the database or not.
+func (bc *BlockChain) HasBlock(hash common.Hash, number uint64) bool {
+	if bc.blockCache.Contains(hash) {
+		return true
+	}
+	ok, _ := bc.chainDb.Has(blockBodyKey(hash, number))
+	return ok
 }
 
 // HasBlockAndState checks if a block and associated state trie is fully present
@@ -693,108 +695,73 @@ func SetReceiptsData(config *params.ChainConfig, block *types.Block, receipts ty
 
 // InsertReceiptChain attempts to complete an already existing header chain with
 // transaction and receipt data.
-// XXX should this be moved to the test?
 func (bc *BlockChain) InsertReceiptChain(blockChain types.Blocks, receiptChain []types.Receipts) (int, error) {
+	bc.wg.Add(1)
+	defer bc.wg.Done()
+
 	// Do a sanity check that the provided chain is actually ordered and linked
 	for i := 1; i < len(blockChain); i++ {
 		if blockChain[i].NumberU64() != blockChain[i-1].NumberU64()+1 || blockChain[i].ParentHash() != blockChain[i-1].Hash() {
-			// Chain broke ancestry, log a messge (programming error) and skip insertion
 			log.Error("Non contiguous receipt insert", "number", blockChain[i].Number(), "hash", blockChain[i].Hash(), "parent", blockChain[i].ParentHash(),
 				"prevnumber", blockChain[i-1].Number(), "prevhash", blockChain[i-1].Hash())
-
 			return 0, fmt.Errorf("non contiguous insert: item %d is #%d [%x…], item %d is #%d [%x…] (parent [%x…])", i-1, blockChain[i-1].NumberU64(),
 				blockChain[i-1].Hash().Bytes()[:4], i, blockChain[i].NumberU64(), blockChain[i].Hash().Bytes()[:4], blockChain[i].ParentHash().Bytes()[:4])
 		}
 	}
-	// Pre-checks passed, start the block body and receipt imports
-	bc.wg.Add(1)
-	defer bc.wg.Done()
 
-	// Collect some import statistics to report on
-	stats := struct{ processed, ignored int32 }{}
-	start := time.Now()
+	var (
+		stats = struct{ processed, ignored int32 }{}
+		start = time.Now()
+		bytes = 0
+		batch = bc.chainDb.NewBatch()
+	)
+	for i, block := range blockChain {
+		receipts := receiptChain[i]
+		// Short circuit insertion if shutting down or processing failed
+		if atomic.LoadInt32(&bc.procInterrupt) == 1 {
+			return 0, nil
+		}
+		// Short circuit if the owner header is unknown
+		if !bc.HasHeader(block.Hash(), block.NumberU64()) {
+			return i, fmt.Errorf("containing header #%d [%x…] unknown", block.Number(), block.Hash().Bytes()[:4])
+		}
+		// Skip if the entire data is already known
+		if bc.HasBlock(block.Hash(), block.NumberU64()) {
+			stats.ignored++
+			continue
+		}
+		// Compute all the non-consensus fields of the receipts
+		SetReceiptsData(bc.config, block, receipts)
+		// Write all the data out into the database
+		if err := WriteBody(batch, block.Hash(), block.NumberU64(), block.Body()); err != nil {
+			return i, fmt.Errorf("failed to write block body: %v", err)
+		}
+		if err := WriteBlockReceipts(batch, block.Hash(), block.NumberU64(), receipts); err != nil {
+			return i, fmt.Errorf("failed to write block receipts: %v", err)
+		}
+		if err := WriteTxLookupEntries(batch, block); err != nil {
+			return i, fmt.Errorf("failed to write lookup metadata: %v", err)
+		}
+		stats.processed++
 
-	// Create the block importing task queue and worker functions
-	tasks := make(chan int, len(blockChain))
-	for i := 0; i < len(blockChain) && i < len(receiptChain); i++ {
-		tasks <- i
-	}
-	close(tasks)
-
-	errs, failed := make([]error, len(tasks)), int32(0)
-	process := func(worker int) {
-		for index := range tasks {
-			block, receipts := blockChain[index], receiptChain[index]
-
-			// Short circuit insertion if shutting down or processing failed
-			if atomic.LoadInt32(&bc.procInterrupt) == 1 {
-				return
+		if batch.ValueSize() >= ethdb.IdealBatchSize {
+			if err := batch.Write(); err != nil {
+				return 0, err
 			}
-			if atomic.LoadInt32(&failed) > 0 {
-				return
-			}
-			// Short circuit if the owner header is unknown
-			if !bc.HasHeader(block.Hash()) {
-				errs[index] = fmt.Errorf("containing header #%d [%x…] unknown", block.Number(), block.Hash().Bytes()[:4])
-				atomic.AddInt32(&failed, 1)
-				return
-			}
-			// Skip if the entire data is already known
-			if bc.HasBlock(block.Hash()) {
-				atomic.AddInt32(&stats.ignored, 1)
-				continue
-			}
-			// Compute all the non-consensus fields of the receipts
-			SetReceiptsData(bc.config, block, receipts)
-			// Write all the data out into the database
-			if err := WriteBody(bc.chainDb, block.Hash(), block.NumberU64(), block.Body()); err != nil {
-				errs[index] = fmt.Errorf("failed to write block body: %v", err)
-				atomic.AddInt32(&failed, 1)
-				log.Crit("Failed to write block body", "err", err)
-				return
-			}
-			if err := WriteBlockReceipts(bc.chainDb, block.Hash(), block.NumberU64(), receipts); err != nil {
-				errs[index] = fmt.Errorf("failed to write block receipts: %v", err)
-				atomic.AddInt32(&failed, 1)
-				log.Crit("Failed to write block receipts", "err", err)
-				return
-			}
-			if err := WriteTxLookupEntries(bc.chainDb, block); err != nil {
-				errs[index] = fmt.Errorf("failed to write lookup metadata: %v", err)
-				atomic.AddInt32(&failed, 1)
-				log.Crit("Failed to write lookup metadata", "err", err)
-				return
-			}
-			atomic.AddInt32(&stats.processed, 1)
+			bytes += batch.ValueSize()
+			batch = bc.chainDb.NewBatch()
 		}
 	}
-	// Start as many worker threads as goroutines allowed
-	pending := new(sync.WaitGroup)
-	for i := 0; i < runtime.GOMAXPROCS(0); i++ {
-		pending.Add(1)
-		go func(id int) {
-			defer pending.Done()
-			process(id)
-		}(i)
-	}
-	pending.Wait()
-
-	// If anything failed, report
-	if failed > 0 {
-		for i, err := range errs {
-			if err != nil {
-				return i, err
-			}
+	if batch.ValueSize() > 0 {
+		bytes += batch.ValueSize()
+		if err := batch.Write(); err != nil {
+			return 0, err
 		}
 	}
-	if atomic.LoadInt32(&bc.procInterrupt) == 1 {
-		log.Debug("Premature abort during receipts processing")
-		return 0, nil
-	}
+
 	// Update the head fast sync block if better
 	bc.mu.Lock()
-
-	head := blockChain[len(errs)-1]
+	head := blockChain[len(blockChain)-1]
 	if td := bc.GetTd(head.Hash(), head.NumberU64()); td != nil { // Rewind may have occurred, skip in that case
 		if bc.GetTd(bc.currentFastBlock.Hash(), bc.currentFastBlock.NumberU64()).Cmp(td) < 0 {
 			if err := WriteHeadFastBlockHash(bc.chainDb, head.Hash()); err != nil {
@@ -805,16 +772,18 @@ func (bc *BlockChain) InsertReceiptChain(blockChain types.Blocks, receiptChain [
 	}
 	bc.mu.Unlock()
 
-	// Report some public statistics so the user has a clue what's going on
-	last := blockChain[len(blockChain)-1]
-	log.Info("Imported new block receipts", "count", stats.processed, "elapsed", common.PrettyDuration(time.Since(start)),
-		"number", last.Number(), "hash", last.Hash(), "ignored", stats.ignored)
-
+	log.Info("Imported new block receipts",
+		"count", stats.processed,
+		"elapsed", common.PrettyDuration(time.Since(start)),
+		"bytes", bytes,
+		"number", head.Number(),
+		"hash", head.Hash(),
+		"ignored", stats.ignored)
 	return 0, nil
 }
 
 // WriteBlock writes the block to the chain.
-func (bc *BlockChain) WriteBlock(block *types.Block) (status WriteStatus, err error) {
+func (bc *BlockChain) WriteBlockAndState(block *types.Block, receipts []*types.Receipt, state *state.StateDB) (status WriteStatus, err error) {
 	bc.wg.Add(1)
 	defer bc.wg.Done()
 
@@ -827,7 +796,7 @@ func (bc *BlockChain) WriteBlock(block *types.Block) (status WriteStatus, err er
 	bc.mu.Lock()
 	defer bc.mu.Unlock()
 
-	if bc.HasBlock(block.Hash()) {
+	if bc.HasBlock(block.Hash(), block.NumberU64()) {
 		log.Trace("Block existed", "hash", block.Hash())
 		return
 	}
@@ -837,10 +806,18 @@ func (bc *BlockChain) WriteBlock(block *types.Block) (status WriteStatus, err er
 
 	// Irrelevant of the canonical status, write the block itself to the database
 	if err := bc.hc.WriteTd(block.Hash(), block.NumberU64(), externTd); err != nil {
-		log.Crit("Failed to write block total difficulty", "err", err)
+		return NonStatTy, err
 	}
-	if err := WriteBlock(bc.chainDb, block); err != nil {
-		log.Crit("Failed to write block contents", "err", err)
+	// Write other block data using a batch.
+	batch := bc.chainDb.NewBatch()
+	if err := WriteBlock(batch, block); err != nil {
+		return NonStatTy, err
+	}
+	if _, err := state.CommitTo(batch, bc.config.IsEIP158(block.Number())); err != nil {
+		return NonStatTy, err
+	}
+	if err := WriteBlockReceipts(batch, block.Hash(), block.NumberU64(), receipts); err != nil {
+		return NonStatTy, err
 	}
 
 	// If the total difficulty is higher than our known, add it to the canonical chain
@@ -853,15 +830,28 @@ func (bc *BlockChain) WriteBlock(block *types.Block) (status WriteStatus, err er
 				return NonStatTy, err
 			}
 		}
-		bc.insert(block) // Insert the block as the new head of the chain
+		// Write the positional metadata for transaction and receipt lookups
+		if err := WriteTxLookupEntries(batch, block); err != nil {
+			return NonStatTy, err
+		}
+		// Write hash preimages
+		if err := WritePreimages(bc.chainDb, block.NumberU64(), state.Preimages()); err != nil {
+			return NonStatTy, err
+		}
 		status = CanonStatTy
 	} else {
 		status = SideStatTy
 	}
+	if err := batch.Write(); err != nil {
+		return NonStatTy, err
+	}
 
+	// Set new head.
+	if status == CanonStatTy {
+		bc.insert(block)
+	}
 	bc.futureBlocks.Remove(block.Hash())
-
-	return
+	return status, nil
 }
 
 // InsertChain will attempt to insert the given chain in to the canonical chain or, otherwise, create a fork. If an error is returned
@@ -975,29 +965,18 @@ func (bc *BlockChain) InsertChain(chain types.Blocks) (int, error) {
 			bc.reportBlock(block, receipts, err)
 			return i, err
 		}
-		// Write state changes to database
-		if _, err = state.CommitTo(bc.chainDb, bc.config.IsEIP158(block.Number())); err != nil {
-			return i, err
-		}
 
-		// coalesce logs for later processing
-		coalescedLogs = append(coalescedLogs, logs...)
-
-		if err = WriteBlockReceipts(bc.chainDb, block.Hash(), block.NumberU64(), receipts); err != nil {
-			return i, err
-		}
-
-		// write the block to the chain and get the status
-		status, err := bc.WriteBlock(block)
+		// Write the block to the chain and get the status.
+		status, err := bc.WriteBlockAndState(block, receipts, state)
 		if err != nil {
 			return i, err
 		}
-
 		switch status {
 		case CanonStatTy:
 			log.Debug("Inserted new block", "number", block.Number(), "hash", block.Hash(), "uncles", len(block.Uncles()),
 				"txs", len(block.Transactions()), "gas", block.GasUsed(), "elapsed", common.PrettyDuration(time.Since(bstart)))
-
+			// coalesce logs for later processing
+			coalescedLogs = append(coalescedLogs, logs...)
 			blockInsertTimer.UpdateSince(bstart)
 			events = append(events, ChainEvent{block, block.Hash(), logs})
 			// We need some control over the mining operation. Acquiring locks and waiting
@@ -1006,15 +985,6 @@ func (bc *BlockChain) InsertChain(chain types.Blocks) (int, error) {
 			if bc.LastBlockHash() == block.Hash() {
 				events = append(events, ChainHeadEvent{block})
 			}
-
-			// Write the positional metadata for transaction and receipt lookups
-			if err := WriteTxLookupEntries(bc.chainDb, block); err != nil {
-				return i, err
-			}
-			// Write hash preimages
-			if err := WritePreimages(bc.chainDb, block.NumberU64(), state.Preimages()); err != nil {
-				return i, err
-			}
 		case SideStatTy:
 			log.Debug("Inserted forked block", "number", block.Number(), "hash", block.Hash(), "diff", block.Difficulty(), "elapsed",
 				common.PrettyDuration(time.Since(bstart)), "txs", len(block.Transactions()), "gas", block.GasUsed(), "uncles", len(block.Uncles()))
@@ -1357,8 +1327,8 @@ func (bc *BlockChain) GetHeaderByHash(hash common.Hash) *types.Header {
 
 // HasHeader checks if a block header is present in the database or not, caching
 // it if present.
-func (bc *BlockChain) HasHeader(hash common.Hash) bool {
-	return bc.hc.HasHeader(hash)
+func (bc *BlockChain) HasHeader(hash common.Hash, number uint64) bool {
+	return bc.hc.HasHeader(hash, number)
 }
 
 // GetBlockHashesFromHash retrieves a number of block hashes starting at a given
diff --git a/core/database_util.go b/core/database_util.go
index 989071104e..1730a048e7 100644
--- a/core/database_util.go
+++ b/core/database_util.go
@@ -38,11 +38,6 @@ type DatabaseReader interface {
 	Get(key []byte) (value []byte, err error)
 }
 
-// DatabaseWriter wraps the Put method of a backing data store.
-type DatabaseWriter interface {
-	Put(key, value []byte) error
-}
-
 // DatabaseDeleter wraps the Delete method of a backing data store.
 type DatabaseDeleter interface {
 	Delete(key []byte) error
@@ -154,7 +149,7 @@ func GetHeadFastBlockHash(db DatabaseReader) common.Hash {
 // GetHeaderRLP retrieves a block header in its raw RLP database encoding, or nil
 // if the header's not found.
 func GetHeaderRLP(db DatabaseReader, hash common.Hash, number uint64) rlp.RawValue {
-	data, _ := db.Get(append(append(headerPrefix, encodeBlockNumber(number)...), hash.Bytes()...))
+	data, _ := db.Get(headerKey(hash, number))
 	return data
 }
 
@@ -175,10 +170,18 @@ func GetHeader(db DatabaseReader, hash common.Hash, number uint64) *types.Header
 
 // GetBodyRLP retrieves the block body (transactions and uncles) in RLP encoding.
 func GetBodyRLP(db DatabaseReader, hash common.Hash, number uint64) rlp.RawValue {
-	data, _ := db.Get(append(append(bodyPrefix, encodeBlockNumber(number)...), hash.Bytes()...))
+	data, _ := db.Get(blockBodyKey(hash, number))
 	return data
 }
 
+func headerKey(hash common.Hash, number uint64) []byte {
+	return append(append(headerPrefix, encodeBlockNumber(number)...), hash.Bytes()...)
+}
+
+func blockBodyKey(hash common.Hash, number uint64) []byte {
+	return append(append(bodyPrefix, encodeBlockNumber(number)...), hash.Bytes()...)
+}
+
 // GetBody retrieves the block body (transactons, uncles) corresponding to the
 // hash, nil if none found.
 func GetBody(db DatabaseReader, hash common.Hash, number uint64) *types.Body {
@@ -340,7 +343,7 @@ func GetBloomBits(db DatabaseReader, bit uint, section uint64, head common.Hash)
 }
 
 // WriteCanonicalHash stores the canonical hash for the given block number.
-func WriteCanonicalHash(db DatabaseWriter, hash common.Hash, number uint64) error {
+func WriteCanonicalHash(db ethdb.Putter, hash common.Hash, number uint64) error {
 	key := append(append(headerPrefix, encodeBlockNumber(number)...), numSuffix...)
 	if err := db.Put(key, hash.Bytes()); err != nil {
 		log.Crit("Failed to store number to hash mapping", "err", err)
@@ -349,7 +352,7 @@ func WriteCanonicalHash(db DatabaseWriter, hash common.Hash, number uint64) erro
 }
 
 // WriteHeadHeaderHash stores the head header's hash.
-func WriteHeadHeaderHash(db DatabaseWriter, hash common.Hash) error {
+func WriteHeadHeaderHash(db ethdb.Putter, hash common.Hash) error {
 	if err := db.Put(headHeaderKey, hash.Bytes()); err != nil {
 		log.Crit("Failed to store last header's hash", "err", err)
 	}
@@ -357,7 +360,7 @@ func WriteHeadHeaderHash(db DatabaseWriter, hash common.Hash) error {
 }
 
 // WriteHeadBlockHash stores the head block's hash.
-func WriteHeadBlockHash(db DatabaseWriter, hash common.Hash) error {
+func WriteHeadBlockHash(db ethdb.Putter, hash common.Hash) error {
 	if err := db.Put(headBlockKey, hash.Bytes()); err != nil {
 		log.Crit("Failed to store last block's hash", "err", err)
 	}
@@ -365,7 +368,7 @@ func WriteHeadBlockHash(db DatabaseWriter, hash common.Hash) error {
 }
 
 // WriteHeadFastBlockHash stores the fast head block's hash.
-func WriteHeadFastBlockHash(db DatabaseWriter, hash common.Hash) error {
+func WriteHeadFastBlockHash(db ethdb.Putter, hash common.Hash) error {
 	if err := db.Put(headFastKey, hash.Bytes()); err != nil {
 		log.Crit("Failed to store last fast block's hash", "err", err)
 	}
@@ -373,7 +376,7 @@ func WriteHeadFastBlockHash(db DatabaseWriter, hash common.Hash) error {
 }
 
 // WriteHeader serializes a block header into the database.
-func WriteHeader(db DatabaseWriter, header *types.Header) error {
+func WriteHeader(db ethdb.Putter, header *types.Header) error {
 	data, err := rlp.EncodeToBytes(header)
 	if err != nil {
 		return err
@@ -393,7 +396,7 @@ func WriteHeader(db DatabaseWriter, header *types.Header) error {
 }
 
 // WriteBody serializes the body of a block into the database.
-func WriteBody(db DatabaseWriter, hash common.Hash, number uint64, body *types.Body) error {
+func WriteBody(db ethdb.Putter, hash common.Hash, number uint64, body *types.Body) error {
 	data, err := rlp.EncodeToBytes(body)
 	if err != nil {
 		return err
@@ -402,7 +405,7 @@ func WriteBody(db DatabaseWriter, hash common.Hash, number uint64, body *types.B
 }
 
 // WriteBodyRLP writes a serialized body of a block into the database.
-func WriteBodyRLP(db DatabaseWriter, hash common.Hash, number uint64, rlp rlp.RawValue) error {
+func WriteBodyRLP(db ethdb.Putter, hash common.Hash, number uint64, rlp rlp.RawValue) error {
 	key := append(append(bodyPrefix, encodeBlockNumber(number)...), hash.Bytes()...)
 	if err := db.Put(key, rlp); err != nil {
 		log.Crit("Failed to store block body", "err", err)
@@ -411,7 +414,7 @@ func WriteBodyRLP(db DatabaseWriter, hash common.Hash, number uint64, rlp rlp.Ra
 }
 
 // WriteTd serializes the total difficulty of a block into the database.
-func WriteTd(db DatabaseWriter, hash common.Hash, number uint64, td *big.Int) error {
+func WriteTd(db ethdb.Putter, hash common.Hash, number uint64, td *big.Int) error {
 	data, err := rlp.EncodeToBytes(td)
 	if err != nil {
 		return err
@@ -424,7 +427,7 @@ func WriteTd(db DatabaseWriter, hash common.Hash, number uint64, td *big.Int) er
 }
 
 // WriteBlock serializes a block into the database, header and body separately.
-func WriteBlock(db DatabaseWriter, block *types.Block) error {
+func WriteBlock(db ethdb.Putter, block *types.Block) error {
 	// Store the body first to retain database consistency
 	if err := WriteBody(db, block.Hash(), block.NumberU64(), block.Body()); err != nil {
 		return err
@@ -439,7 +442,7 @@ func WriteBlock(db DatabaseWriter, 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 DatabaseWriter, hash common.Hash, number uint64, receipts types.Receipts) error {
+func WriteBlockReceipts(db ethdb.Putter, 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 {
@@ -459,9 +462,7 @@ func WriteBlockReceipts(db DatabaseWriter, hash common.Hash, number uint64, rece
 
 // WriteTxLookupEntries stores a positional metadata for every transaction from
 // a block, enabling hash based transaction and receipt lookups.
-func WriteTxLookupEntries(db ethdb.Database, block *types.Block) error {
-	batch := db.NewBatch()
-
+func WriteTxLookupEntries(db ethdb.Putter, block *types.Block) error {
 	// Iterate over each transaction and encode its metadata
 	for i, tx := range block.Transactions() {
 		entry := txLookupEntry{
@@ -473,20 +474,16 @@ func WriteTxLookupEntries(db ethdb.Database, block *types.Block) error {
 		if err != nil {
 			return err
 		}
-		if err := batch.Put(append(lookupPrefix, tx.Hash().Bytes()...), data); err != nil {
+		if err := db.Put(append(lookupPrefix, tx.Hash().Bytes()...), data); err != nil {
 			return err
 		}
 	}
-	// Write the scheduled data into the database
-	if err := batch.Write(); err != nil {
-		log.Crit("Failed to store lookup entries", "err", err)
-	}
 	return nil
 }
 
 // WriteBloomBits writes the compressed bloom bits vector belonging to the given
 // section and bit index.
-func WriteBloomBits(db DatabaseWriter, bit uint, section uint64, head common.Hash, bits []byte) {
+func WriteBloomBits(db ethdb.Putter, bit uint, section uint64, head common.Hash, bits []byte) {
 	key := append(append(bloomBitsPrefix, make([]byte, 10)...), head.Bytes()...)
 
 	binary.BigEndian.PutUint16(key[1:], uint16(bit))
@@ -572,13 +569,13 @@ func GetBlockChainVersion(db DatabaseReader) int {
 }
 
 // WriteBlockChainVersion writes vsn as the version number to db.
-func WriteBlockChainVersion(db DatabaseWriter, vsn int) {
+func WriteBlockChainVersion(db ethdb.Putter, vsn int) {
 	enc, _ := rlp.EncodeToBytes(uint(vsn))
 	db.Put([]byte("BlockchainVersion"), enc)
 }
 
 // WriteChainConfig writes the chain config settings to the database.
-func WriteChainConfig(db DatabaseWriter, hash common.Hash, cfg *params.ChainConfig) error {
+func WriteChainConfig(db ethdb.Putter, hash common.Hash, cfg *params.ChainConfig) error {
 	// short circuit and ignore if nil config. GetChainConfig
 	// will return a default.
 	if cfg == nil {
diff --git a/core/headerchain.go b/core/headerchain.go
index 6ec44b61d5..0e5215293d 100644
--- a/core/headerchain.go
+++ b/core/headerchain.go
@@ -267,7 +267,7 @@ func (hc *HeaderChain) InsertHeaderChain(chain []*types.Header, writeHeader WhCa
 			return i, errors.New("aborted")
 		}
 		// If the header's already known, skip it, otherwise store
-		if hc.GetHeader(header.Hash(), header.Number.Uint64()) != nil {
+		if hc.HasHeader(header.Hash(), header.Number.Uint64()) {
 			stats.ignored++
 			continue
 		}
@@ -361,10 +361,13 @@ 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.GetHeaderByHash(hash) != nil
+// HasHeader checks if a block header is present in the database or not.
+func (hc *HeaderChain) HasHeader(hash common.Hash, number uint64) bool {
+	if hc.numberCache.Contains(hash) || hc.headerCache.Contains(hash) {
+		return true
+	}
+	ok, _ := hc.chainDb.Has(headerKey(hash, number))
+	return ok
 }
 
 // GetHeaderByNumber retrieves a block header from the database by number,
diff --git a/core/state/sync.go b/core/state/sync.go
index 2c29d706aa..28fcf6ae05 100644
--- a/core/state/sync.go
+++ b/core/state/sync.go
@@ -18,60 +18,24 @@ package state
 
 import (
 	"bytes"
-	"math/big"
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/rlp"
 	"github.com/ethereum/go-ethereum/trie"
 )
 
-// StateSync is the main state synchronisation scheduler, which provides yet the
-// unknown state hashes to retrieve, accepts node data associated with said hashes
-// and reconstructs the state database step by step until all is done.
-type StateSync trie.TrieSync
-
 // NewStateSync create a new state trie download scheduler.
-func NewStateSync(root common.Hash, database trie.DatabaseReader) *StateSync {
+func NewStateSync(root common.Hash, database trie.DatabaseReader) *trie.TrieSync {
 	var syncer *trie.TrieSync
-
 	callback := func(leaf []byte, parent common.Hash) error {
-		var obj struct {
-			Nonce    uint64
-			Balance  *big.Int
-			Root     common.Hash
-			CodeHash []byte
-		}
+		var obj Account
 		if err := rlp.Decode(bytes.NewReader(leaf), &obj); err != nil {
 			return err
 		}
 		syncer.AddSubTrie(obj.Root, 64, parent, nil)
 		syncer.AddRawEntry(common.BytesToHash(obj.CodeHash), 64, parent)
-
 		return nil
 	}
 	syncer = trie.NewTrieSync(root, database, callback)
-	return (*StateSync)(syncer)
-}
-
-// Missing retrieves the known missing nodes from the state trie for retrieval.
-func (s *StateSync) Missing(max int) []common.Hash {
-	return (*trie.TrieSync)(s).Missing(max)
-}
-
-// Process injects a batch of retrieved trie nodes data, returning if something
-// was committed to the memcache and also the index of an entry if processing of
-// it failed.
-func (s *StateSync) Process(list []trie.SyncResult) (bool, int, error) {
-	return (*trie.TrieSync)(s).Process(list)
-}
-
-// Commit flushes the data stored in the internal memcache out to persistent
-// storage, returning th enumber of items written and any occurred error.
-func (s *StateSync) Commit(dbw trie.DatabaseWriter) (int, error) {
-	return (*trie.TrieSync)(s).Commit(dbw)
-}
-
-// Pending returns the number of state entries currently pending for download.
-func (s *StateSync) Pending() int {
-	return (*trie.TrieSync)(s).Pending()
+	return syncer
 }
diff --git a/eth/api.go b/eth/api.go
index 9904c6f536..a5b6e7076c 100644
--- a/eth/api.go
+++ b/eth/api.go
@@ -241,7 +241,7 @@ func (api *PrivateAdminAPI) ExportChain(file string) (bool, error) {
 
 func hasAllBlocks(chain *core.BlockChain, bs []*types.Block) bool {
 	for _, b := range bs {
-		if !chain.HasBlock(b.Hash()) {
+		if !chain.HasBlock(b.Hash(), b.NumberU64()) {
 			return false
 		}
 	}
diff --git a/eth/downloader/downloader.go b/eth/downloader/downloader.go
index f2dbf0f88a..38b66d9dd5 100644
--- a/eth/downloader/downloader.go
+++ b/eth/downloader/downloader.go
@@ -156,7 +156,7 @@ type Downloader struct {
 // LightChain encapsulates functions required to synchronise a light chain.
 type LightChain interface {
 	// HasHeader verifies a header's presence in the local chain.
-	HasHeader(common.Hash) bool
+	HasHeader(h common.Hash, number uint64) bool
 
 	// GetHeaderByHash retrieves a header from the local chain.
 	GetHeaderByHash(common.Hash) *types.Header
@@ -666,7 +666,7 @@ func (d *Downloader) findAncestor(p *peerConnection, height uint64) (uint64, err
 					continue
 				}
 				// Otherwise check if we already know the header or not
-				if (d.mode == FullSync && d.blockchain.HasBlockAndState(headers[i].Hash())) || (d.mode != FullSync && d.lightchain.HasHeader(headers[i].Hash())) {
+				if (d.mode == FullSync && d.blockchain.HasBlockAndState(headers[i].Hash())) || (d.mode != FullSync && d.lightchain.HasHeader(headers[i].Hash(), headers[i].Number.Uint64())) {
 					number, hash = headers[i].Number.Uint64(), headers[i].Hash()
 
 					// If every header is known, even future ones, the peer straight out lied about its head
@@ -731,7 +731,7 @@ func (d *Downloader) findAncestor(p *peerConnection, height uint64) (uint64, err
 				arrived = true
 
 				// Modify the search interval based on the response
-				if (d.mode == FullSync && !d.blockchain.HasBlockAndState(headers[0].Hash())) || (d.mode != FullSync && !d.lightchain.HasHeader(headers[0].Hash())) {
+				if (d.mode == FullSync && !d.blockchain.HasBlockAndState(headers[0].Hash())) || (d.mode != FullSync && !d.lightchain.HasHeader(headers[0].Hash(), headers[0].Number.Uint64())) {
 					end = check
 					break
 				}
@@ -1256,7 +1256,7 @@ func (d *Downloader) processHeaders(origin uint64, td *big.Int) error {
 					// Collect the yet unknown headers to mark them as uncertain
 					unknown := make([]*types.Header, 0, len(headers))
 					for _, header := range chunk {
-						if !d.lightchain.HasHeader(header.Hash()) {
+						if !d.lightchain.HasHeader(header.Hash(), header.Number.Uint64()) {
 							unknown = append(unknown, header)
 						}
 					}
diff --git a/eth/downloader/downloader_test.go b/eth/downloader/downloader_test.go
index d66aafe94e..58f6e9a624 100644
--- a/eth/downloader/downloader_test.go
+++ b/eth/downloader/downloader_test.go
@@ -217,7 +217,7 @@ func (dl *downloadTester) sync(id string, td *big.Int, mode SyncMode) error {
 }
 
 // HasHeader checks if a header is present in the testers canonical chain.
-func (dl *downloadTester) HasHeader(hash common.Hash) bool {
+func (dl *downloadTester) HasHeader(hash common.Hash, number uint64) bool {
 	return dl.GetHeaderByHash(hash) != nil
 }
 
diff --git a/eth/downloader/statesync.go b/eth/downloader/statesync.go
index a5ce8c42df..eb5416f63c 100644
--- a/eth/downloader/statesync.go
+++ b/eth/downloader/statesync.go
@@ -26,6 +26,7 @@ import (
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/state"
 	"github.com/ethereum/go-ethereum/crypto/sha3"
+	"github.com/ethereum/go-ethereum/ethdb"
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/trie"
 )
@@ -187,10 +188,13 @@ func (d *Downloader) runStateSync(s *stateSync) *stateSync {
 type stateSync struct {
 	d *Downloader // Downloader instance to access and manage current peerset
 
-	sched  *state.StateSync           // State trie sync scheduler defining the tasks
+	sched  *trie.TrieSync             // State trie sync scheduler defining the tasks
 	keccak hash.Hash                  // Keccak256 hasher to verify deliveries with
 	tasks  map[common.Hash]*stateTask // Set of tasks currently queued for retrieval
 
+	numUncommitted   int
+	bytesUncommitted int
+
 	deliver    chan *stateReq // Delivery channel multiplexing peer responses
 	cancel     chan struct{}  // Channel to signal a termination request
 	cancelOnce sync.Once      // Ensures cancel only ever gets called once
@@ -252,9 +256,10 @@ func (s *stateSync) loop() error {
 
 	// Keep assigning new tasks until the sync completes or aborts
 	for s.sched.Pending() > 0 {
-		if err := s.assignTasks(); err != nil {
+		if err := s.commit(false); err != nil {
 			return err
 		}
+		s.assignTasks()
 		// Tasks assigned, wait for something to happen
 		select {
 		case <-newPeer:
@@ -284,12 +289,28 @@ func (s *stateSync) loop() error {
 			}
 		}
 	}
+	return s.commit(true)
+}
+
+func (s *stateSync) commit(force bool) error {
+	if !force && s.bytesUncommitted < ethdb.IdealBatchSize {
+		return nil
+	}
+	start := time.Now()
+	b := s.d.stateDB.NewBatch()
+	s.sched.Commit(b)
+	if err := b.Write(); err != nil {
+		return fmt.Errorf("DB write error: %v", err)
+	}
+	s.updateStats(s.numUncommitted, 0, 0, time.Since(start))
+	s.numUncommitted = 0
+	s.bytesUncommitted = 0
 	return nil
 }
 
 // assignTasks attempts to assing new tasks to all idle peers, either from the
 // batch currently being retried, or fetching new data from the trie sync itself.
-func (s *stateSync) assignTasks() error {
+func (s *stateSync) assignTasks() {
 	// Iterate over all idle peers and try to assign them state fetches
 	peers, _ := s.d.peers.NodeDataIdlePeers()
 	for _, p := range peers {
@@ -301,7 +322,6 @@ func (s *stateSync) assignTasks() error {
 		// If the peer was assigned tasks to fetch, send the network request
 		if len(req.items) > 0 {
 			req.peer.log.Trace("Requesting new batch of data", "type", "state", "count", len(req.items))
-
 			select {
 			case s.d.trackStateReq <- req:
 				req.peer.FetchNodeData(req.items)
@@ -309,7 +329,6 @@ func (s *stateSync) assignTasks() error {
 			}
 		}
 	}
-	return nil
 }
 
 // fillTasks fills the given request object with a maximum of n state download
@@ -347,11 +366,11 @@ func (s *stateSync) fillTasks(n int, req *stateReq) {
 // delivered.
 func (s *stateSync) process(req *stateReq) (bool, error) {
 	// Collect processing stats and update progress if valid data was received
-	processed, written, duplicate, unexpected := 0, 0, 0, 0
+	duplicate, unexpected := 0, 0
 
 	defer func(start time.Time) {
-		if processed+written+duplicate+unexpected > 0 {
-			s.updateStats(processed, written, duplicate, unexpected, time.Since(start))
+		if duplicate > 0 || unexpected > 0 {
+			s.updateStats(0, duplicate, unexpected, time.Since(start))
 		}
 	}(time.Now())
 
@@ -362,7 +381,9 @@ func (s *stateSync) process(req *stateReq) (bool, error) {
 		prog, hash, err := s.processNodeData(blob)
 		switch err {
 		case nil:
-			processed++
+			s.numUncommitted++
+			s.bytesUncommitted += len(blob)
+			progress = progress || prog
 		case trie.ErrNotRequested:
 			unexpected++
 		case trie.ErrAlreadyProcessed:
@@ -370,38 +391,20 @@ func (s *stateSync) process(req *stateReq) (bool, error) {
 		default:
 			return stale, fmt.Errorf("invalid state node %s: %v", hash.TerminalString(), err)
 		}
-		if prog {
-			progress = true
-		}
 		// If the node delivered a requested item, mark the delivery non-stale
 		if _, ok := req.tasks[hash]; ok {
 			delete(req.tasks, hash)
 			stale = false
 		}
 	}
-	// If some data managed to hit the database, flush and reset failure counters
-	if progress {
-		// Flush any accumulated data out to disk
-		batch := s.d.stateDB.NewBatch()
-
-		count, err := s.sched.Commit(batch)
-		if err != nil {
-			return stale, err
-		}
-		if err := batch.Write(); err != nil {
-			return stale, err
-		}
-		written = count
-
-		// If we're inside the critical section, reset fail counter since we progressed
-		if atomic.LoadUint32(&s.d.fsPivotFails) > 1 {
-			log.Trace("Fast-sync progressed, resetting fail counter", "previous", atomic.LoadUint32(&s.d.fsPivotFails))
-			atomic.StoreUint32(&s.d.fsPivotFails, 1) // Don't ever reset to 0, as that will unlock the pivot block
-		}
+	// If we're inside the critical section, reset fail counter since we progressed.
+	if progress && atomic.LoadUint32(&s.d.fsPivotFails) > 1 {
+		log.Trace("Fast-sync progressed, resetting fail counter", "previous", atomic.LoadUint32(&s.d.fsPivotFails))
+		atomic.StoreUint32(&s.d.fsPivotFails, 1) // Don't ever reset to 0, as that will unlock the pivot block
 	}
+
 	// Put unfulfilled tasks back into the retry queue
 	npeers := s.d.peers.Len()
-
 	for hash, task := range req.tasks {
 		// If the node did deliver something, missing items may be due to a protocol
 		// limit or a previous timeout + delayed delivery. Both cases should permit
@@ -425,25 +428,25 @@ func (s *stateSync) process(req *stateReq) (bool, error) {
 // error occurred.
 func (s *stateSync) processNodeData(blob []byte) (bool, common.Hash, error) {
 	res := trie.SyncResult{Data: blob}
-
 	s.keccak.Reset()
 	s.keccak.Write(blob)
 	s.keccak.Sum(res.Hash[:0])
-
 	committed, _, err := s.sched.Process([]trie.SyncResult{res})
 	return committed, res.Hash, err
 }
 
 // updateStats bumps the various state sync progress counters and displays a log
 // message for the user to see.
-func (s *stateSync) updateStats(processed, written, duplicate, unexpected int, duration time.Duration) {
+func (s *stateSync) updateStats(written, duplicate, unexpected int, duration time.Duration) {
 	s.d.syncStatsLock.Lock()
 	defer s.d.syncStatsLock.Unlock()
 
 	s.d.syncStatsState.pending = uint64(s.sched.Pending())
-	s.d.syncStatsState.processed += uint64(processed)
+	s.d.syncStatsState.processed += uint64(written)
 	s.d.syncStatsState.duplicate += uint64(duplicate)
 	s.d.syncStatsState.unexpected += uint64(unexpected)
 
-	log.Info("Imported new state entries", "count", processed, "flushed", written, "elapsed", common.PrettyDuration(duration), "processed", s.d.syncStatsState.processed, "pending", s.d.syncStatsState.pending, "retry", len(s.tasks), "duplicate", s.d.syncStatsState.duplicate, "unexpected", s.d.syncStatsState.unexpected)
+	if written > 0 || duplicate > 0 || unexpected > 0 {
+		log.Info("Imported new state entries", "count", written, "elapsed", common.PrettyDuration(duration), "processed", s.d.syncStatsState.processed, "pending", s.d.syncStatsState.pending, "retry", len(s.tasks), "duplicate", s.d.syncStatsState.duplicate, "unexpected", s.d.syncStatsState.unexpected)
+	}
 }
diff --git a/eth/handler.go b/eth/handler.go
index 28ae208c06..cee719ddb6 100644
--- a/eth/handler.go
+++ b/eth/handler.go
@@ -609,7 +609,7 @@ func (pm *ProtocolManager) handleMsg(p *peer) error {
 		// Schedule all the unknown hashes for retrieval
 		unknown := make(newBlockHashesData, 0, len(announces))
 		for _, block := range announces {
-			if !pm.blockchain.HasBlock(block.Hash) {
+			if !pm.blockchain.HasBlock(block.Hash, block.Number) {
 				unknown = append(unknown, block)
 			}
 		}
@@ -699,7 +699,7 @@ func (pm *ProtocolManager) BroadcastBlock(block *types.Block, propagate bool) {
 		return
 	}
 	// Otherwise if the block is indeed in out own chain, announce it
-	if pm.blockchain.HasBlock(hash) {
+	if pm.blockchain.HasBlock(hash, block.NumberU64()) {
 		for _, peer := range peers {
 			peer.SendNewBlockHashes([]common.Hash{hash}, []uint64{block.NumberU64()})
 		}
diff --git a/ethdb/database.go b/ethdb/database.go
index 7d5fb0b9ef..93755dd7e3 100644
--- a/ethdb/database.go
+++ b/ethdb/database.go
@@ -109,6 +109,10 @@ func (db *LDBDatabase) Put(key []byte, value []byte) error {
 	return db.db.Put(key, value, nil)
 }
 
+func (db *LDBDatabase) Has(key []byte) (bool, error) {
+	return db.db.Has(key, nil)
+}
+
 // Get returns the given key if it's present.
 func (db *LDBDatabase) Get(key []byte) ([]byte, error) {
 	// Measure the database get latency, if requested
@@ -271,19 +275,19 @@ func (db *LDBDatabase) meter(refresh time.Duration) {
 	}
 }
 
-// TODO: remove this stuff and expose leveldb directly
-
 func (db *LDBDatabase) NewBatch() Batch {
 	return &ldbBatch{db: db.db, b: new(leveldb.Batch)}
 }
 
 type ldbBatch struct {
-	db *leveldb.DB
-	b  *leveldb.Batch
+	db   *leveldb.DB
+	b    *leveldb.Batch
+	size int
 }
 
 func (b *ldbBatch) Put(key, value []byte) error {
 	b.b.Put(key, value)
+	b.size += len(value)
 	return nil
 }
 
@@ -291,6 +295,10 @@ func (b *ldbBatch) Write() error {
 	return b.db.Write(b.b, nil)
 }
 
+func (b *ldbBatch) ValueSize() int {
+	return b.size
+}
+
 type table struct {
 	db     Database
 	prefix string
@@ -309,6 +317,10 @@ func (dt *table) Put(key []byte, value []byte) error {
 	return dt.db.Put(append([]byte(dt.prefix), key...), value)
 }
 
+func (dt *table) Has(key []byte) (bool, error) {
+	return dt.db.Has(append([]byte(dt.prefix), key...))
+}
+
 func (dt *table) Get(key []byte) ([]byte, error) {
 	return dt.db.Get(append([]byte(dt.prefix), key...))
 }
@@ -342,3 +354,7 @@ func (tb *tableBatch) Put(key, value []byte) error {
 func (tb *tableBatch) Write() error {
 	return tb.batch.Write()
 }
+
+func (tb *tableBatch) ValueSize() int {
+	return tb.batch.ValueSize()
+}
diff --git a/ethdb/interface.go b/ethdb/interface.go
index f4b787a52a..99a5b770d5 100644
--- a/ethdb/interface.go
+++ b/ethdb/interface.go
@@ -16,15 +16,29 @@
 
 package ethdb
 
-type Database interface {
+// Code using batches should try to add this much data to the batch.
+// The value was determined empirically.
+const IdealBatchSize = 100 * 1024
+
+// Putter wraps the database write operation supported by both batches and regular databases.
+type Putter interface {
 	Put(key []byte, value []byte) error
+}
+
+// Database wraps all database operations. All methods are safe for concurrent use.
+type Database interface {
+	Putter
 	Get(key []byte) ([]byte, error)
+	Has(key []byte) (bool, error)
 	Delete(key []byte) error
 	Close()
 	NewBatch() Batch
 }
 
+// Batch is a write-only database that commits changes to its host database
+// when Write is called. Batch cannot be used concurrently.
 type Batch interface {
-	Put(key, value []byte) error
+	Putter
+	ValueSize() int // amount of data in the batch
 	Write() error
 }
diff --git a/ethdb/memory_database.go b/ethdb/memory_database.go
index 11b0937248..699bd0c9fd 100644
--- a/ethdb/memory_database.go
+++ b/ethdb/memory_database.go
@@ -45,6 +45,14 @@ func (db *MemDatabase) Put(key []byte, value []byte) error {
 	return nil
 }
 
+func (db *MemDatabase) Has(key []byte) (bool, error) {
+	db.lock.RLock()
+	defer db.lock.RUnlock()
+
+	_, ok := db.db[string(key)]
+	return ok, nil
+}
+
 func (db *MemDatabase) Get(key []byte) ([]byte, error) {
 	db.lock.RLock()
 	defer db.lock.RUnlock()
@@ -93,21 +101,16 @@ type kv struct{ k, v []byte }
 type memBatch struct {
 	db     *MemDatabase
 	writes []kv
-	lock   sync.RWMutex
+	size   int
 }
 
 func (b *memBatch) Put(key, value []byte) error {
-	b.lock.Lock()
-	defer b.lock.Unlock()
-
 	b.writes = append(b.writes, kv{common.CopyBytes(key), common.CopyBytes(value)})
+	b.size += len(value)
 	return nil
 }
 
 func (b *memBatch) Write() error {
-	b.lock.RLock()
-	defer b.lock.RUnlock()
-
 	b.db.lock.Lock()
 	defer b.db.lock.Unlock()
 
@@ -116,3 +119,7 @@ func (b *memBatch) Write() error {
 	}
 	return nil
 }
+
+func (b *memBatch) ValueSize() int {
+	return b.size
+}
diff --git a/les/handler.go b/les/handler.go
index 1a75cd369d..df7eb6af51 100644
--- a/les/handler.go
+++ b/les/handler.go
@@ -70,7 +70,7 @@ func errResp(code errCode, format string, v ...interface{}) error {
 }
 
 type BlockChain interface {
-	HasHeader(hash common.Hash) bool
+	HasHeader(hash common.Hash, number uint64) bool
 	GetHeader(hash common.Hash, number uint64) *types.Header
 	GetHeaderByHash(hash common.Hash) *types.Header
 	CurrentHeader() *types.Header
diff --git a/light/lightchain.go b/light/lightchain.go
index df194ecadf..3a763fc906 100644
--- a/light/lightchain.go
+++ b/light/lightchain.go
@@ -252,8 +252,8 @@ func (self *LightChain) GetBodyRLP(ctx context.Context, hash common.Hash) (rlp.R
 
 // HasBlock checks if a block is fully present in the database or not, caching
 // it if present.
-func (bc *LightChain) HasBlock(hash common.Hash) bool {
-	blk, _ := bc.GetBlockByHash(NoOdr, hash)
+func (bc *LightChain) HasBlock(hash common.Hash, number uint64) bool {
+	blk, _ := bc.GetBlock(NoOdr, hash, number)
 	return blk != nil
 }
 
@@ -418,8 +418,8 @@ func (self *LightChain) GetHeaderByHash(hash common.Hash) *types.Header {
 
 // HasHeader checks if a block header is present in the database or not, caching
 // it if present.
-func (bc *LightChain) HasHeader(hash common.Hash) bool {
-	return bc.hc.HasHeader(hash)
+func (bc *LightChain) HasHeader(hash common.Hash, number uint64) bool {
+	return bc.hc.HasHeader(hash, number)
 }
 
 // GetBlockHashesFromHash retrieves a number of block hashes starting at a given
diff --git a/miner/worker.go b/miner/worker.go
index 2919d4a485..b48db2a30e 100644
--- a/miner/worker.go
+++ b/miner/worker.go
@@ -304,13 +304,8 @@ func (self *worker) wait() {
 				}
 				go self.mux.Post(core.NewMinedBlockEvent{Block: block})
 			} else {
-				work.state.CommitTo(self.chainDb, self.config.IsEIP158(block.Number()))
-				stat, err := self.chain.WriteBlock(block)
-				if err != nil {
-					log.Error("Failed writing block to chain", "err", err)
-					continue
-				}
-				// update block hash since it is now available and not when the receipt/log of individual transactions were created
+				// Update the block hash in all logs since it is now available and not when the
+				// receipt/log of individual transactions were created.
 				for _, r := range work.receipts {
 					for _, l := range r.Logs {
 						l.BlockHash = block.Hash()
@@ -319,15 +314,17 @@ func (self *worker) wait() {
 				for _, log := range work.state.Logs() {
 					log.BlockHash = block.Hash()
 				}
+				stat, err := self.chain.WriteBlockAndState(block, work.receipts, work.state)
+				if err != nil {
+					log.Error("Failed writing block to chain", "err", err)
+					continue
+				}
 
 				// check if canon block and write transactions
 				if stat == core.CanonStatTy {
-					// This puts transactions in a extra db for rpc
-					core.WriteTxLookupEntries(self.chainDb, block)
 					// implicit by posting ChainHeadEvent
 					mustCommitNewWork = false
 				}
-
 				// broadcast before waiting for validation
 				go func(block *types.Block, logs []*types.Log, receipts []*types.Receipt) {
 					self.mux.Post(core.NewMinedBlockEvent{Block: block})
@@ -336,16 +333,12 @@ func (self *worker) wait() {
 						coalescedLogs []*types.Log
 					)
 					events = append(events, core.ChainEvent{Block: block, Hash: block.Hash(), Logs: logs})
-
 					if stat == core.CanonStatTy {
 						events = append(events, core.ChainHeadEvent{Block: block})
 						coalescedLogs = logs
 					}
 					// post blockchain events
 					self.chain.PostChainEvents(events, coalescedLogs)
-					if err := core.WriteBlockReceipts(self.chainDb, block.Hash(), block.NumberU64(), receipts); err != nil {
-						log.Warn("Failed writing block receipts", "err", err)
-					}
 				}(block, work.state.Logs(), work.receipts)
 			}
 			// Insert the block into the set of pending ones to wait for confirmations
diff --git a/trie/sync.go b/trie/sync.go
index 1e4f8d87c1..fea10051f4 100644
--- a/trie/sync.go
+++ b/trie/sync.go
@@ -138,7 +138,7 @@ func (s *TrieSync) AddRawEntry(hash common.Hash, depth int, parent common.Hash)
 	if _, ok := s.membatch.batch[hash]; ok {
 		return
 	}
-	if blob, _ := s.database.Get(hash.Bytes()); blob != nil {
+	if ok, _ := s.database.Has(hash.Bytes()); ok {
 		return
 	}
 	// Assemble the new sub-trie sync request
@@ -296,8 +296,7 @@ func (s *TrieSync) children(req *request, object node) ([]*request, error) {
 			if _, ok := s.membatch.batch[hash]; ok {
 				continue
 			}
-			blob, _ := s.database.Get(node)
-			if local, err := decodeNode(node[:], blob, 0); local != nil && err == nil {
+			if ok, _ := s.database.Has(node); ok {
 				continue
 			}
 			// Locally unknown node, schedule for retrieval
diff --git a/trie/trie.go b/trie/trie.go
index a3151b1ce7..7f69a3d1de 100644
--- a/trie/trie.go
+++ b/trie/trie.go
@@ -66,6 +66,7 @@ type Database interface {
 // DatabaseReader wraps the Get method of a backing store for the trie.
 type DatabaseReader interface {
 	Get(key []byte) (value []byte, err error)
+	Has(key []byte) (bool, error)
 }
 
 // DatabaseWriter wraps the Put method of a backing store for the trie.