Simplify miner gas limit post EIP-1559. Default to 30M (#3205) (#3274)

Co-authored-by: Andrew Ashikhmin <34320705+yperbasis@users.noreply.github.com>

cmd/integration/commands/flags.go

@@ -39,8 +39,7 @@ func must(err error) {
 func withMining(cmd *cobra.Command) {
 	cmd.Flags().Bool("mine", false, "Enable mining")
 	cmd.Flags().StringArray("miner.notify", nil, "Comma separated HTTP URL list to notify of new work packages")
-	cmd.Flags().Uint64("miner.gastarget", ethconfig.Defaults.Miner.GasFloor, "Target gas floor for mined blocks")
-	cmd.Flags().Uint64("miner.gaslimit", ethconfig.Defaults.Miner.GasCeil, "Target gas ceiling for mined blocks")
+	cmd.Flags().Uint64("miner.gaslimit", ethconfig.Defaults.Miner.GasLimit, "Target gas limit for mined blocks")
 	cmd.Flags().Int64("miner.gasprice", ethconfig.Defaults.Miner.GasPrice.Int64(), "Target gas price for mined blocks")
 	cmd.Flags().String("miner.etherbase", "0", "Public address for block mining rewards (default = first account")
 	cmd.Flags().String("miner.extradata", "", "Block extra data set by the miner (default = client version)")

cmd/utils/flags.go

@@ -228,15 +228,10 @@ var (
 		Name:  "miner.notify",
 		Usage: "Comma separated HTTP URL list to notify of new work packages",
 	}
-	MinerGasTargetFlag = cli.Uint64Flag{
-		Name:  "miner.gastarget",
-		Usage: "Target gas floor for mined blocks",
-		Value: ethconfig.Defaults.Miner.GasFloor,
-	}
 	MinerGasLimitFlag = cli.Uint64Flag{
 		Name:  "miner.gaslimit",
-		Usage: "Target gas ceiling for mined blocks",
-		Value: ethconfig.Defaults.Miner.GasCeil,
+		Usage: "Target gas limit for mined blocks",
+		Value: ethconfig.Defaults.Miner.GasLimit,
 	}
 	MinerGasPriceFlag = BigFlag{
 		Name:  "miner.gasprice",
@@ -1075,11 +1070,7 @@ func SetupMinerCobra(cmd *cobra.Command, cfg *params.MiningConfig) {
 		panic(err)
 	}
 	cfg.ExtraData = []byte(extraDataStr)
-	cfg.GasFloor, err = flags.GetUint64(MinerGasTargetFlag.Name)
-	if err != nil {
-		panic(err)
-	}
-	cfg.GasCeil, err = flags.GetUint64(MinerGasLimitFlag.Name)
+	cfg.GasLimit, err = flags.GetUint64(MinerGasLimitFlag.Name)
 	if err != nil {
 		panic(err)
 	}
@@ -1139,11 +1130,8 @@ func setMiner(ctx *cli.Context, cfg *params.MiningConfig) {
 	if ctx.GlobalIsSet(MinerExtraDataFlag.Name) {
 		cfg.ExtraData = []byte(ctx.GlobalString(MinerExtraDataFlag.Name))
 	}
-	if ctx.GlobalIsSet(MinerGasTargetFlag.Name) {
-		cfg.GasFloor = ctx.GlobalUint64(MinerGasTargetFlag.Name)
-	}
 	if ctx.GlobalIsSet(MinerGasLimitFlag.Name) {
-		cfg.GasCeil = ctx.GlobalUint64(MinerGasLimitFlag.Name)
+		cfg.GasLimit = ctx.GlobalUint64(MinerGasLimitFlag.Name)
 	}
 	if ctx.GlobalIsSet(MinerGasPriceFlag.Name) {
 		cfg.GasPrice = GlobalBig(ctx, MinerGasPriceFlag.Name)

core/block_validator.go

@@ -21,37 +21,26 @@ import (
 )
 
 // CalcGasLimit computes the gas limit of the next block after parent. It aims
-// to keep the baseline gas above the provided floor, and increase it towards the
-// ceil if the blocks are full. If the ceil is exceeded, it will always decrease
-// the gas allowance.
-func CalcGasLimit(parentGasUsed, parentGasLimit, gasFloor, gasCeil uint64) uint64 {
-	// contrib = (parentGasUsed * 3 / 2) / 1024
-	contrib := (parentGasUsed + parentGasUsed/2) / params.GasLimitBoundDivisor
-
-	// decay = parentGasLimit / 1024 -1
-	decay := parentGasLimit/params.GasLimitBoundDivisor - 1
-
-	/*
-		strategy: gasLimit of block-to-mine is set based on parent's
-		gasUsed value.  if parentGasUsed > parentGasLimit * (2/3) then we
-		increase it, otherwise lower it (or leave it unchanged if it's right
-		at that usage) the amount increased/decreased depends on how far away
-		from parentGasLimit * (2/3) parentGasUsed is.
-	*/
-	limit := parentGasLimit - decay + contrib
-	if limit < params.MinGasLimit {
-		limit = params.MinGasLimit
+// to keep the baseline gas close to the provided target, and increase it towards
+// the target if the baseline gas is lower.
+func CalcGasLimit(parentGasLimit, desiredLimit uint64) uint64 {
+	delta := parentGasLimit/params.GasLimitBoundDivisor - 1
+	limit := parentGasLimit
+	if desiredLimit < params.MinGasLimit {
+		desiredLimit = params.MinGasLimit
 	}
 	// If we're outside our allowed gas range, we try to hone towards them
-	if limit < gasFloor {
-		limit = parentGasLimit + decay
-		if limit > gasFloor {
-			limit = gasFloor
+	if limit < desiredLimit {
+		limit = parentGasLimit + delta
+		if limit > desiredLimit {
+			limit = desiredLimit
 		}
-	} else if limit > gasCeil {
-		limit = parentGasLimit - decay
-		if limit < gasCeil {
-			limit = gasCeil
+		return limit
+	}
+	if limit > desiredLimit {
+		limit = parentGasLimit - delta
+		if limit < desiredLimit {
+			limit = desiredLimit
 		}
 	}
 	return limit

core/chain_makers.go

@@ -404,7 +404,7 @@ func makeHeader(chain consensus.ChainReader, parent *types.Block, state *state.I
 			parent.UncleHash(),
 			parent.Header().Seal,
 		),
-		GasLimit: CalcGasLimit(parent.GasUsed(), parent.GasLimit(), parent.GasLimit(), parent.GasLimit()),
+		GasLimit: CalcGasLimit(parent.GasLimit(), parent.GasLimit()),
 		Number:   new(big.Int).Add(parent.Number(), common.Big1),
 		Time:     time,
 	}
@@ -413,6 +413,10 @@ func makeHeader(chain consensus.ChainReader, parent *types.Block, state *state.I
 	if chain.Config().IsLondon(header.Number.Uint64()) {
 		header.BaseFee = misc.CalcBaseFee(chain.Config(), parent.Header())
 		header.Eip1559 = true
+		if !chain.Config().IsLondon(parent.NumberU64()) {
+			parentGasLimit := parent.GasLimit() * params.ElasticityMultiplier
+			header.GasLimit = CalcGasLimit(parentGasLimit, parentGasLimit)
+		}
 	}
 	header.WithSeal = chain.Config().IsHeaderWithSeal()
 

eth/ethconfig/config.go

@@ -76,8 +76,7 @@ var Defaults = Config{
 	NetworkID: 1,
 	Prune:     prune.DefaultMode,
 	Miner: params.MiningConfig{
-		GasFloor: 8000000,
-		GasCeil:  8000000,
+		GasLimit: 30_000_000,
 		GasPrice: big.NewInt(params.GWei),
 		Recommit: 3 * time.Second,
 	},

eth/stagedsync/stage_mining_create_block.go

@@ -213,7 +213,7 @@ func SpawnMiningCreateBlockStage(s *StageState, tx kv.RwTx, cfg MiningCreateBloc
 	header := &types.Header{
 		ParentHash: parent.Hash(),
 		Number:     num.Add(num, common.Big1),
-		GasLimit:   core.CalcGasLimit(parent.GasUsed, parent.GasLimit, cfg.miner.MiningConfig.GasFloor, cfg.miner.MiningConfig.GasCeil),
+		GasLimit:   core.CalcGasLimit(parent.GasLimit, cfg.miner.MiningConfig.GasLimit),
 		Extra:      cfg.miner.MiningConfig.ExtraData,
 		Time:       uint64(timestamp),
 	}
@@ -224,7 +224,7 @@ func SpawnMiningCreateBlockStage(s *StageState, tx kv.RwTx, cfg MiningCreateBloc
 		header.BaseFee = misc.CalcBaseFee(&cfg.chainConfig, parent)
 		if !cfg.chainConfig.IsLondon(parent.Number.Uint64()) {
 			parentGasLimit := parent.GasLimit * params.ElasticityMultiplier
-			header.GasLimit = core.CalcGasLimit(parent.GasUsed, parentGasLimit, cfg.miner.MiningConfig.GasFloor, cfg.miner.MiningConfig.GasCeil)
+			header.GasLimit = core.CalcGasLimit(parentGasLimit, cfg.miner.MiningConfig.GasLimit)
 		}
 	}
 	log.Info(fmt.Sprintf("[%s] Start mine", logPrefix), "block", executionAt+1, "baseFee", header.BaseFee, "gasLimit", header.GasLimit)

params/mining.go

@@ -17,8 +17,7 @@ type MiningConfig struct {
 	SigKey    *ecdsa.PrivateKey // ECDSA private key for signing blocks
 	Notify    []string          `toml:",omitempty"` // HTTP URL list to be notified of new work packages(only useful in ethash).
 	ExtraData hexutil.Bytes     `toml:",omitempty"` // Block extra data set by the miner
-	GasFloor  uint64            // Target gas floor for mined blocks.
-	GasCeil   uint64            // Target gas ceiling for mined blocks.
+	GasLimit  uint64            // Target gas limit for mined blocks.
 	GasPrice  *big.Int          // Minimum gas price for mining a transaction
 	Recommit  time.Duration     // The time interval for miner to re-create mining work.
 }

turbo/cli/default_flags.go

@@ -77,7 +77,6 @@ var DefaultFlags = []cli.Flag{
 	utils.CliqueDataDirFlag,
 	utils.MiningEnabledFlag,
 	utils.MinerNotifyFlag,
-	utils.MinerGasTargetFlag,
 	utils.MinerGasLimitFlag,
 	utils.MinerEtherbaseFlag,
 	utils.MinerExtraDataFlag,