core: optimize HasHeader check

This avoids one random database read get the block number. For many uses
of HasHeader, the expectation is that it's actually there. Using Has
avoids a load + decode of the value.

core/blockchain.go

@@ -734,7 +734,7 @@ func (bc *BlockChain) InsertReceiptChain(blockChain types.Blocks, receiptChain [
 				return
 			}
 			// Short circuit if the owner header is unknown
-			if !bc.HasHeader(block.Hash()) {
+			if !bc.HasHeader(block.Hash(), block.NumberU64()) {
 				errs[index] = fmt.Errorf("containing header #%d [%x…] unknown", block.Number(), block.Hash().Bytes()[:4])
 				atomic.AddInt32(&failed, 1)
 				return
@@ -1357,8 +1357,8 @@ 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 {
+func (bc *BlockChain) HasHeader(hash common.Hash, number uint64) bool {
-	return bc.hc.HasHeader(hash)
+	return bc.hc.HasHeader(hash, number)
 }
 
 // GetBlockHashesFromHash retrieves a number of block hashes starting at a given

core/database_util.go

@@ -149,7 +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
 }
 
@@ -174,6 +174,10 @@ func GetBodyRLP(db DatabaseReader, hash common.Hash, number uint64) rlp.RawValue
 	return data
 }
 
+func headerKey(hash common.Hash, number uint64) []byte {
+	return append(append(headerPrefix, 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 {

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
+// HasHeader checks if a block header is present in the database or not.
-// it if present.
+func (hc *HeaderChain) HasHeader(hash common.Hash, number uint64) bool {
-func (hc *HeaderChain) HasHeader(hash common.Hash) bool {
+	if _, ok := hc.headerCache.Get(hash); ok {
-	return hc.GetHeaderByHash(hash) != nil
+		return true
+	}
+	ok, _ := hc.chainDb.Has(headerKey(hash, number))
+	return ok
 }
 
 // GetHeaderByNumber retrieves a block header from the database by number,

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)
 						}
 					}

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
 }
 

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

light/lightchain.go

@@ -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 {
+func (bc *LightChain) HasHeader(hash common.Hash, number uint64) bool {
-	return bc.hc.HasHeader(hash)
+	return bc.hc.HasHeader(hash, number)
 }
 
 // GetBlockHashesFromHash retrieves a number of block hashes starting at a given