core: initialize history pruning in BlockChain (#31636)

I added the history mode configuration in eth/ethconfig initially, since
it seemed like the logical place. But it turns out we need access to the
intended pruning setting at a deeper level, and it actually needs to be
integrated with the blockchain startup procedure.

With this change applied, if a node previously had its history pruned,
and is subsequently restarted **without** the `--history.chain
postmerge` flag, the `BlockChain` initialization code will now verify
the freezer tail against the known pruning point of the predefined
network and will restore pruning status. Note that this logic is quite
restrictive, we allow non-zero tail only for known networks, and only
for the specific pruning point that is defined.

Author: fjl

cmd/geth/chaincmd.go

@@ -31,11 +31,11 @@ import (
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/hexutil"
 	"github.com/ethereum/go-ethereum/core"
+	"github.com/ethereum/go-ethereum/core/history"
 	"github.com/ethereum/go-ethereum/core/rawdb"
 	"github.com/ethereum/go-ethereum/core/state"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/crypto"
-	"github.com/ethereum/go-ethereum/eth/ethconfig"
 	"github.com/ethereum/go-ethereum/ethdb"
 	"github.com/ethereum/go-ethereum/internal/debug"
 	"github.com/ethereum/go-ethereum/internal/era"
@@ -625,7 +625,7 @@ func pruneHistory(ctx *cli.Context) error {
 	defer chain.Stop()
 
 	// Determine the prune point. This will be the first PoS block.
-	prunePoint, ok := ethconfig.HistoryPrunePoints[chain.Genesis().Hash()]
+	prunePoint, ok := history.PrunePoints[chain.Genesis().Hash()]
 	if !ok || prunePoint == nil {
 		return errors.New("prune point not found")
 	}

cmd/workload/testsuite.go

@@ -23,7 +23,7 @@ import (
 	"os"
 	"slices"
 
-	"github.com/ethereum/go-ethereum/eth/ethconfig"
+	"github.com/ethereum/go-ethereum/core/history"
 	"github.com/ethereum/go-ethereum/internal/flags"
 	"github.com/ethereum/go-ethereum/internal/utesting"
 	"github.com/ethereum/go-ethereum/log"
@@ -124,13 +124,13 @@ func testConfigFromCLI(ctx *cli.Context) (cfg testConfig) {
 		cfg.filterQueryFile = "queries/filter_queries_mainnet.json"
 		cfg.historyTestFile = "queries/history_mainnet.json"
 		cfg.historyPruneBlock = new(uint64)
-		*cfg.historyPruneBlock = ethconfig.HistoryPrunePoints[params.MainnetGenesisHash].BlockNumber
+		*cfg.historyPruneBlock = history.PrunePoints[params.MainnetGenesisHash].BlockNumber
 	case ctx.Bool(testSepoliaFlag.Name):
 		cfg.fsys = builtinTestFiles
 		cfg.filterQueryFile = "queries/filter_queries_sepolia.json"
 		cfg.historyTestFile = "queries/history_sepolia.json"
 		cfg.historyPruneBlock = new(uint64)
-		*cfg.historyPruneBlock = ethconfig.HistoryPrunePoints[params.SepoliaGenesisHash].BlockNumber
+		*cfg.historyPruneBlock = history.PrunePoints[params.SepoliaGenesisHash].BlockNumber
 	default:
 		cfg.fsys = os.DirFS(".")
 		cfg.filterQueryFile = ctx.String(filterQueryFileFlag.Name)

core/block_validator_test.go

@@ -50,8 +50,11 @@ func testHeaderVerification(t *testing.T, scheme string) {
 		headers[i] = block.Header()
 	}
 	// Run the header checker for blocks one-by-one, checking for both valid and invalid nonces
-	chain, _ := NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil)
+	chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), DefaultCacheConfigWithScheme(scheme), gspec, nil, ethash.NewFaker(), vm.Config{}, nil)
 	defer chain.Stop()
+	if err != nil {
+		t.Fatal(err)
+	}
 
 	for i := 0; i < len(blocks); i++ {
 		for j, valid := range []bool{true, false} {
@@ -163,8 +166,11 @@ func testHeaderVerificationForMerging(t *testing.T, isClique bool) {
 		postHeaders[i] = block.Header()
 	}
 	// Run the header checker for blocks one-by-one, checking for both valid and invalid nonces
-	chain, _ := NewBlockChain(rawdb.NewMemoryDatabase(), nil, gspec, nil, engine, vm.Config{}, nil)
+	chain, err := NewBlockChain(rawdb.NewMemoryDatabase(), nil, gspec, nil, engine, vm.Config{}, nil)
 	defer chain.Stop()
+	if err != nil {
+		t.Fatal(err)
+	}
 
 	// Verify the blocks before the merging
 	for i := 0; i < len(preBlocks); i++ {

core/blockchain.go

@@ -36,6 +36,7 @@ import (
 	"github.com/ethereum/go-ethereum/common/prque"
 	"github.com/ethereum/go-ethereum/consensus"
 	"github.com/ethereum/go-ethereum/consensus/misc/eip4844"
+	"github.com/ethereum/go-ethereum/core/history"
 	"github.com/ethereum/go-ethereum/core/rawdb"
 	"github.com/ethereum/go-ethereum/core/state"
 	"github.com/ethereum/go-ethereum/core/state/snapshot"
@@ -158,8 +159,7 @@ type CacheConfig struct {
 
 	// This defines the cutoff block for history expiry.
 	// Blocks before this number may be unavailable in the chain database.
-	HistoryPruningCutoffNumber uint64
-	HistoryPruningCutoffHash   common.Hash
+	ChainHistoryMode history.HistoryMode
 }
 
 // triedbConfig derives the configures for trie database.
@@ -255,6 +255,7 @@ type BlockChain struct {
 	currentSnapBlock  atomic.Pointer[types.Header] // Current head of snap-sync
 	currentFinalBlock atomic.Pointer[types.Header] // Latest (consensus) finalized block
 	currentSafeBlock  atomic.Pointer[types.Header] // Latest (consensus) safe block
+	historyPrunePoint atomic.Pointer[history.PrunePoint]
 
 	bodyCache     *lru.Cache[common.Hash, *types.Body]
 	bodyRLPCache  *lru.Cache[common.Hash, rlp.RawValue]
@@ -533,6 +534,12 @@ func (bc *BlockChain) loadLastState() error {
 	}
 	bc.hc.SetCurrentHeader(headHeader)
 
+	// Initialize history pruning.
+	latest := max(headBlock.NumberU64(), headHeader.Number.Uint64())
+	if err := bc.initializeHistoryPruning(latest); err != nil {
+		return err
+	}
+
 	// Restore the last known head snap block
 	bc.currentSnapBlock.Store(headBlock.Header())
 	headFastBlockGauge.Update(int64(headBlock.NumberU64()))
@@ -555,6 +562,7 @@ func (bc *BlockChain) loadLastState() error {
 			headSafeBlockGauge.Update(int64(block.NumberU64()))
 		}
 	}
+
 	// Issue a status log for the user
 	var (
 		currentSnapBlock  = bc.CurrentSnapBlock()
@@ -573,9 +581,57 @@ func (bc *BlockChain) loadLastState() error {
 	if pivot := rawdb.ReadLastPivotNumber(bc.db); pivot != nil {
 		log.Info("Loaded last snap-sync pivot marker", "number", *pivot)
 	}
+	if pruning := bc.historyPrunePoint.Load(); pruning != nil {
+		log.Info("Chain history is pruned", "earliest", pruning.BlockNumber, "hash", pruning.BlockHash)
+	}
 	return nil
 }
 
+// initializeHistoryPruning sets bc.historyPrunePoint.
+func (bc *BlockChain) initializeHistoryPruning(latest uint64) error {
+	freezerTail, _ := bc.db.Tail()
+
+	switch bc.cacheConfig.ChainHistoryMode {
+	case history.KeepAll:
+		if freezerTail == 0 {
+			return nil
+		}
+		// The database was pruned somehow, so we need to figure out if it's a known
+		// configuration or an error.
+		predefinedPoint := history.PrunePoints[bc.genesisBlock.Hash()]
+		if predefinedPoint == nil || freezerTail != predefinedPoint.BlockNumber {
+			log.Error("Chain history database is pruned with unknown configuration", "tail", freezerTail)
+			return fmt.Errorf("unexpected database tail")
+		}
+		bc.historyPrunePoint.Store(predefinedPoint)
+		return nil
+
+	case history.KeepPostMerge:
+		if freezerTail == 0 && latest != 0 {
+			// This is the case where a user is trying to run with --history.chain
+			// postmerge directly on an existing DB. We could just trigger the pruning
+			// here, but it'd be a bit dangerous since they may not have intended this
+			// action to happen. So just tell them how to do it.
+			log.Error(fmt.Sprintf("Chain history mode is configured as %q, but database is not pruned.", bc.cacheConfig.ChainHistoryMode.String()))
+			log.Error(fmt.Sprintf("Run 'geth prune-history' to prune pre-merge history."))
+			return fmt.Errorf("history pruning requested via configuration")
+		}
+		predefinedPoint := history.PrunePoints[bc.genesisBlock.Hash()]
+		if predefinedPoint == nil {
+			log.Error("Chain history pruning is not supported for this network", "genesis", bc.genesisBlock.Hash())
+			return fmt.Errorf("history pruning requested for unknown network")
+		} else if freezerTail != predefinedPoint.BlockNumber {
+			log.Error("Chain history database is pruned to unknown block", "tail", freezerTail)
+			return fmt.Errorf("unexpected database tail")
+		}
+		bc.historyPrunePoint.Store(predefinedPoint)
+		return nil
+
+	default:
+		return fmt.Errorf("invalid history mode: %d", bc.cacheConfig.ChainHistoryMode)
+	}
+}
+
 // SetHead rewinds the local chain to a new head. Depending on whether the node
 // was snap synced or full synced and in which state, the method will try to
 // delete minimal data from disk whilst retaining chain consistency.
@@ -1014,7 +1070,9 @@ func (bc *BlockChain) ResetWithGenesisBlock(genesis *types.Block) error {
 	bc.hc.SetCurrentHeader(bc.genesisBlock.Header())
 	bc.currentSnapBlock.Store(bc.genesisBlock.Header())
 	headFastBlockGauge.Update(int64(bc.genesisBlock.NumberU64()))
-	return nil
+
+	// Reset history pruning status.
+	return bc.initializeHistoryPruning(0)
 }
 
 // Export writes the active chain to the given writer.

core/blockchain_reader.go

@@ -410,7 +410,11 @@ func (bc *BlockChain) TxIndexProgress() (TxIndexProgress, error) {
 // HistoryPruningCutoff returns the configured history pruning point.
 // Blocks before this might not be available in the database.
 func (bc *BlockChain) HistoryPruningCutoff() (uint64, common.Hash) {
-	return bc.cacheConfig.HistoryPruningCutoffNumber, bc.cacheConfig.HistoryPruningCutoffHash
+	pt := bc.historyPrunePoint.Load()
+	if pt == nil {
+		return 0, bc.genesisBlock.Hash()
+	}
+	return pt.BlockNumber, pt.BlockHash
 }
 
 // TrieDB retrieves the low level trie database used for data storage.

core/blockchain_test.go

@@ -33,6 +33,7 @@ import (
 	"github.com/ethereum/go-ethereum/consensus"
 	"github.com/ethereum/go-ethereum/consensus/beacon"
 	"github.com/ethereum/go-ethereum/consensus/ethash"
+	"github.com/ethereum/go-ethereum/core/history"
 	"github.com/ethereum/go-ethereum/core/rawdb"
 	"github.com/ethereum/go-ethereum/core/state"
 	"github.com/ethereum/go-ethereum/core/types"
@@ -4257,13 +4258,7 @@ func testChainReorgSnapSync(t *testing.T, ancientLimit uint64) {
 // be persisted without the receipts and bodies; chain after should be persisted
 // normally.
 func TestInsertChainWithCutoff(t *testing.T) {
-	testInsertChainWithCutoff(t, 32, 32) // cutoff = 32, ancientLimit = 32
-	testInsertChainWithCutoff(t, 32, 64) // cutoff = 32, ancientLimit = 64 (entire chain in ancient)
-	testInsertChainWithCutoff(t, 32, 65) // cutoff = 32, ancientLimit = 65 (64 blocks in ancient, 1 block in live)
-}
-
-func testInsertChainWithCutoff(t *testing.T, cutoff uint64, ancientLimit uint64) {
-	// log.SetDefault(log.NewLogger(log.NewTerminalHandlerWithLevel(os.Stderr, log.LevelDebug, true)))
+	const chainLength = 64
 
 	// Configure and generate a sample block chain
 	var (
@@ -4278,24 +4273,51 @@ func testInsertChainWithCutoff(t *testing.T, cutoff uint64, ancientLimit uint64)
 		signer = types.LatestSigner(gspec.Config)
 		engine = beacon.New(ethash.NewFaker())
 	)
-	_, blocks, receipts := GenerateChainWithGenesis(gspec, engine, int(2*cutoff), func(i int, block *BlockGen) {
+	_, blocks, receipts := GenerateChainWithGenesis(gspec, engine, chainLength, func(i int, block *BlockGen) {
 		block.SetCoinbase(common.Address{0x00})
-
 		tx, err := types.SignTx(types.NewTransaction(block.TxNonce(address), common.Address{0x00}, big.NewInt(1000), params.TxGas, block.header.BaseFee, nil), signer, key)
 		if err != nil {
 			panic(err)
 		}
 		block.AddTx(tx)
 	})
-	db, _ := rawdb.NewDatabaseWithFreezer(rawdb.NewMemoryDatabase(), "", "", false)
-	defer db.Close()
 
+	// Run the actual tests.
+	t.Run("cutoff-32/ancientLimit-32", func(t *testing.T) {
+		// cutoff = 32, ancientLimit = 32
+		testInsertChainWithCutoff(t, 32, 32, gspec, blocks, receipts)
+	})
+	t.Run("cutoff-32/ancientLimit-64", func(t *testing.T) {
+		// cutoff = 32, ancientLimit = 64 (entire chain in ancient)
+		testInsertChainWithCutoff(t, 32, 64, gspec, blocks, receipts)
+	})
+	t.Run("cutoff-32/ancientLimit-64", func(t *testing.T) {
+		// cutoff = 32, ancientLimit = 65 (64 blocks in ancient, 1 block in live)
+		testInsertChainWithCutoff(t, 32, 65, gspec, blocks, receipts)
+	})
+}
+
+func testInsertChainWithCutoff(t *testing.T, cutoff uint64, ancientLimit uint64, genesis *Genesis, blocks []*types.Block, receipts []types.Receipts) {
+	// log.SetDefault(log.NewLogger(log.NewTerminalHandlerWithLevel(os.Stderr, log.LevelDebug, true)))
+
+	// Add a known pruning point for the duration of the test.
+	ghash := genesis.ToBlock().Hash()
 	cutoffBlock := blocks[cutoff-1]
+	history.PrunePoints[ghash] = &history.PrunePoint{
+		BlockNumber: cutoffBlock.NumberU64(),
+		BlockHash:   cutoffBlock.Hash(),
+	}
+	defer func() {
+		delete(history.PrunePoints, ghash)
+	}()
+
+	// Enable pruning in cache config.
 	config := DefaultCacheConfigWithScheme(rawdb.PathScheme)
-	config.HistoryPruningCutoffNumber = cutoffBlock.NumberU64()
-	config.HistoryPruningCutoffHash = cutoffBlock.Hash()
+	config.ChainHistoryMode = history.KeepPostMerge
 
-	chain, _ := NewBlockChain(db, DefaultCacheConfigWithScheme(rawdb.PathScheme), gspec, nil, beacon.New(ethash.NewFaker()), vm.Config{}, nil)
+	db, _ := rawdb.NewDatabaseWithFreezer(rawdb.NewMemoryDatabase(), "", "", false)
+	defer db.Close()
+	chain, _ := NewBlockChain(db, DefaultCacheConfigWithScheme(rawdb.PathScheme), genesis, nil, beacon.New(ethash.NewFaker()), vm.Config{}, nil)
 	defer chain.Stop()
 
 	var (
@@ -4326,8 +4348,8 @@ func testInsertChainWithCutoff(t *testing.T, cutoff uint64, ancientLimit uint64)
 		t.Errorf("head header #%d: header mismatch: want: %v, got: %v", headHeader.Number, blocks[len(blocks)-1].Hash(), headHeader.Hash())
 	}
 	headBlock := chain.CurrentBlock()
-	if headBlock.Hash() != gspec.ToBlock().Hash() {
-		t.Errorf("head block #%d: header mismatch: want: %v, got: %v", headBlock.Number, gspec.ToBlock().Hash(), headBlock.Hash())
+	if headBlock.Hash() != ghash {
+		t.Errorf("head block #%d: header mismatch: want: %v, got: %v", headBlock.Number, ghash, headBlock.Hash())
 	}
 
 	// Iterate over all chain data components, and cross reference

eth/ethconfig/historymode.go renamed to core/history/historymode.go

@@ -14,7 +14,7 @@
 // You should have received a copy of the GNU Lesser General Public License
 // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
 
-package ethconfig
+package history
 
 import (
 	"fmt"
@@ -27,22 +27,22 @@ import (
 type HistoryMode uint32
 
 const (
-	// AllHistory (default) means that all chain history down to genesis block will be kept.
-	AllHistory HistoryMode = iota
+	// KeepAll (default) means that all chain history down to genesis block will be kept.
+	KeepAll HistoryMode = iota
 
-	// PostMergeHistory sets the history pruning point to the merge activation block.
-	PostMergeHistory
+	// KeepPostMerge sets the history pruning point to the merge activation block.
+	KeepPostMerge
 )
 
 func (m HistoryMode) IsValid() bool {
-	return m <= PostMergeHistory
+	return m <= KeepPostMerge
 }
 
 func (m HistoryMode) String() string {
 	switch m {
-	case AllHistory:
+	case KeepAll:
 		return "all"
-	case PostMergeHistory:
+	case KeepPostMerge:
 		return "postmerge"
 	default:
 		return fmt.Sprintf("invalid HistoryMode(%d)", m)
@@ -61,24 +61,24 @@ func (m HistoryMode) MarshalText() ([]byte, error) {
 func (m *HistoryMode) UnmarshalText(text []byte) error {
 	switch string(text) {
 	case "all":
-		*m = AllHistory
+		*m = KeepAll
 	case "postmerge":
-		*m = PostMergeHistory
+		*m = KeepPostMerge
 	default:
 		return fmt.Errorf(`unknown sync mode %q, want "all" or "postmerge"`, text)
 	}
 	return nil
 }
 
-type HistoryPrunePoint struct {
+type PrunePoint struct {
 	BlockNumber uint64
 	BlockHash   common.Hash
 }
 
-// HistoryPrunePoints contains the pre-defined history pruning cutoff blocks for known networks.
+// PrunePoints the pre-defined history pruning cutoff blocks for known networks.
 // They point to the first post-merge block. Any pruning should truncate *up to* but excluding
 // given block.
-var HistoryPrunePoints = map[common.Hash]*HistoryPrunePoint{
+var PrunePoints = map[common.Hash]*PrunePoint{
 	// mainnet
 	params.MainnetGenesisHash: {
 		BlockNumber: 15537393,
@@ -91,7 +91,7 @@ var HistoryPrunePoints = map[common.Hash]*HistoryPrunePoint{
 	},
 }
 
-// PrunedHistoryError is returned when the requested history is pruned.
+// PrunedHistoryError is returned by APIs when the requested history is pruned.
 type PrunedHistoryError struct{}
 
 func (e *PrunedHistoryError) Error() string  { return "pruned history unavailable" }