Merge pull request #93 from ethereum-optimism/fix-pending-block

miner,eth: latest block as pending block on rollup

cmd/geth/main.go

@@ -156,6 +156,7 @@ var (
 		utils.RollupHistoricalRPCFlag,
 		utils.RollupHistoricalRPCTimeoutFlag,
 		utils.RollupDisableTxPoolGossipFlag,
+		utils.RollupComputePendingBlock,
 		configFileFlag,
 	}, utils.NetworkFlags, utils.DatabasePathFlags)
 

cmd/utils/flags.go

@@ -941,6 +941,11 @@ var (
 		Usage:    "Disable transaction pool gossip.",
 		Category: flags.RollupCategory,
 	}
+	RollupComputePendingBlock = &cli.BoolFlag{
+		Name:     "rollup.computependingblock",
+		Usage:    "By default the pending block equals the latest block to save resources and not leak txs from the tx-pool, this flag enables computing of the pending block from the tx-pool instead.",
+		Category: flags.RollupCategory,
+	}
 
 	// Metrics flags
 	MetricsEnabledFlag = &cli.BoolFlag{
@@ -1696,6 +1701,9 @@ func setMiner(ctx *cli.Context, cfg *miner.Config) {
 	if ctx.IsSet(MinerNewPayloadTimeout.Name) {
 		cfg.NewPayloadTimeout = ctx.Duration(MinerNewPayloadTimeout.Name)
 	}
+	if ctx.IsSet(RollupComputePendingBlock.Name) {
+		cfg.RollupComputePendingBlock = ctx.Bool(RollupComputePendingBlock.Name)
+	}
 }
 
 func setRequiredBlocks(ctx *cli.Context, cfg *ethconfig.Config) {

eth/api.go

@@ -265,6 +265,9 @@ func (api *DebugAPI) DumpBlock(blockNr rpc.BlockNumber) (state.Dump, error) {
 		// both the pending block as well as the pending state from
 		// the miner and operate on those
 		_, stateDb := api.eth.miner.Pending()
+		if stateDb == nil {
+			return state.Dump{}, errors.New("no pending state")
+		}
 		return stateDb.RawDump(opts), nil
 	}
 	var header *types.Header
@@ -350,6 +353,9 @@ func (api *DebugAPI) AccountRange(blockNrOrHash rpc.BlockNumberOrHash, start hex
 			// both the pending block as well as the pending state from
 			// the miner and operate on those
 			_, stateDb = api.eth.miner.Pending()
+			if stateDb == nil {
+				return state.IteratorDump{}, errors.New("no pending state")
+			}
 		} else {
 			var header *types.Header
 			if number == rpc.LatestBlockNumber {

eth/api_backend.go

@@ -199,7 +199,11 @@ func (b *EthAPIBackend) StateAndHeaderByNumber(ctx context.Context, number rpc.B
 	// Pending state is only known by the miner
 	if number == rpc.PendingBlockNumber {
 		block, state := b.eth.miner.Pending()
-		return state, block.Header(), nil
+		if block != nil {
+			return state, block.Header(), nil
+		} else {
+			number = rpc.LatestBlockNumber
+		}
 	}
 	// Otherwise resolve the block number and return its state
 	header, err := b.HeaderByNumber(ctx, number)

internal/ethapi/api.go

@@ -774,7 +774,7 @@ func (s *BlockChainAPI) GetHeaderByNumber(ctx context.Context, number rpc.BlockN
 	header, err := s.b.HeaderByNumber(ctx, number)
 	if header != nil && err == nil {
 		response := s.rpcMarshalHeader(ctx, header)
-		if number == rpc.PendingBlockNumber {
+		if number == rpc.PendingBlockNumber && s.b.ChainConfig().Optimism == nil { // don't remove info if optimism
 			// Pending header need to nil out a few fields
 			for _, field := range []string{"hash", "nonce", "miner"} {
 				response[field] = nil
@@ -803,7 +803,7 @@ func (s *BlockChainAPI) GetBlockByNumber(ctx context.Context, number rpc.BlockNu
 	block, err := s.b.BlockByNumber(ctx, number)
 	if block != nil && err == nil {
 		response, err := s.rpcMarshalBlock(ctx, block, true, fullTx)
-		if err == nil && number == rpc.PendingBlockNumber {
+		if err == nil && number == rpc.PendingBlockNumber && s.b.ChainConfig().Optimism == nil { // don't remove info if optimism
 			// Pending blocks need to nil out a few fields
 			for _, field := range []string{"hash", "nonce", "miner"} {
 				response[field] = nil

miner/miner.go

@@ -62,6 +62,8 @@ type Config struct {
 	Noverify   bool           // Disable remote mining solution verification(only useful in ethash).
 
 	NewPayloadTimeout time.Duration // The maximum time allowance for creating a new payload
+
+	RollupComputePendingBlock bool // Compute the pending block from tx-pool, instead of copying the latest-block
 }
 
 // DefaultConfig contains default settings for miner.

miner/worker.go

@@ -384,6 +384,9 @@ func (w *worker) enablePreseal() {
 
 // pending returns the pending state and corresponding block.
 func (w *worker) pending() (*types.Block, *state.StateDB) {
+	if w.chainConfig.Optimism != nil && !w.config.RollupComputePendingBlock {
+		return nil, nil // when not computing the pending block, there is never a pending state
+	}
 	// return a snapshot to avoid contention on currentMu mutex
 	w.snapshotMu.RLock()
 	defer w.snapshotMu.RUnlock()
@@ -395,6 +398,12 @@ func (w *worker) pending() (*types.Block, *state.StateDB) {
 
 // pendingBlock returns pending block.
 func (w *worker) pendingBlock() *types.Block {
+	if w.chainConfig.Optimism != nil && !w.config.RollupComputePendingBlock {
+		// For compatibility when not computing a pending block, we serve the latest block as "pending"
+		headHeader := w.eth.BlockChain().CurrentHeader()
+		headBlock := w.eth.BlockChain().GetBlock(headHeader.Hash(), headHeader.Number.Uint64())
+		return headBlock
+	}
 	// return a snapshot to avoid contention on currentMu mutex
 	w.snapshotMu.RLock()
 	defer w.snapshotMu.RUnlock()
@@ -403,6 +412,9 @@ func (w *worker) pendingBlock() *types.Block {
 
 // pendingBlockAndReceipts returns pending block and corresponding receipts.
 func (w *worker) pendingBlockAndReceipts() (*types.Block, types.Receipts) {
+	if w.chainConfig.Optimism != nil && !w.config.RollupComputePendingBlock {
+		return nil, nil // when not computing the pending block, there are no pending receipts, and thus no pending logs
+	}
 	// return a snapshot to avoid contention on currentMu mutex
 	w.snapshotMu.RLock()
 	defer w.snapshotMu.RUnlock()
@@ -458,6 +470,19 @@ func recalcRecommit(minRecommit, prev time.Duration, target float64, inc bool) t
 // newWorkLoop is a standalone goroutine to submit new sealing work upon received events.
 func (w *worker) newWorkLoop(recommit time.Duration) {
 	defer w.wg.Done()
+	if w.chainConfig.Optimism != nil && !w.config.RollupComputePendingBlock {
+		for { // do not update the pending-block, instead drain work without doing it, to keep producers from blocking.
+			select {
+			case <-w.startCh:
+			case <-w.chainHeadCh:
+			case <-w.resubmitIntervalCh:
+			case <-w.resubmitAdjustCh:
+			case <-w.exitCh:
+				return
+			}
+		}
+	}
+
 	var (
 		interrupt   *atomic.Int32
 		minRecommit = recommit // minimal resubmit interval specified by user.
@@ -620,6 +645,9 @@ func (w *worker) mainLoop() {
 			}
 
 		case ev := <-w.txsCh:
+			if w.chainConfig.Optimism != nil && !w.config.RollupComputePendingBlock {
+				continue // don't update the pending-block snapshot if we are not computing the pending block
+			}
 			// Apply transactions to the pending state if we're not sealing
 			//
 			// Note all transactions received may not be continuous with transactions