Tweak the EVM gas price (#714)

* Proper calculation for the WEIGHT_MILLISECS_PER_BLOCK for EVM

* Zero out the DefaultElasticity

* Allow non_snake_case at runtime

* Move DefaultBaseFeePerGas value to consts

* Adjust BLOCK_GAS_LIMIT and move it consts

* Adjust the eth rpc E2E test to the target fee value

* Adjust the max fee per gas estimates in the irrelevant tests

* Add runtime unit test for EVM fee value

* Drop all the sophisticated fee per gas calculation logic

* Set a sensible FEE_PER_GAS value with a proper rationale

* Cleanup the obsolete base and dynamic fee pallet integrations

* Tweak BLOCK_GAS_LIMIT and EVM fee unit test epsilon

* Rename the simple_evm_transaction to simple_evm_transaction_via_query_call_info

* Share the assert_fee fn

* Add a proper EVM runtime estimate test for the fee cost

crates/humanode-peer/Cargo.toml

@@ -43,7 +43,6 @@ futures = "0.3"
 hex = "0.4.3"
 hex-literal = "0.4"
 pallet-balances = { default-features = false, git = "https://github.com/humanode-network/substrate", branch = "locked/polkadot-v0.9.38" }
-pallet-dynamic-fee = { default-features = false, git = "https://github.com/humanode-network/frontier", branch = "locked/polkadot-v0.9.38" }
 pallet-im-online = { default-features = false, git = "https://github.com/humanode-network/substrate", branch = "locked/polkadot-v0.9.38" }
 pallet-transaction-payment = { default-features = false, git = "https://github.com/humanode-network/substrate", branch = "locked/polkadot-v0.9.38" }
 qr2term = "0.3"
@@ -114,7 +113,6 @@ try-runtime = [
   "humanode-runtime/try-runtime",
   "pallet-balances/try-runtime",
   "pallet-bioauth/try-runtime",
-  "pallet-dynamic-fee/try-runtime",
   "pallet-im-online/try-runtime",
   "pallet-transaction-payment/try-runtime",
   "pallet-token-claims/try-runtime",

crates/humanode-peer/src/benchmarking.rs

@@ -11,7 +11,7 @@ use humanode_runtime::{AccountId, Balance, BalancesCall, SystemCall, SLOT_DURATI
 use sc_client_api::BlockBackend;
 use sp_api::ProvideRuntimeApi;
 use sp_consensus_babe::SlotDuration;
-use sp_core::{Encode, Pair, U256};
+use sp_core::{Encode, Pair};
 use sp_inherents::{InherentData, InherentDataProvider};
 use sp_keyring::Sr25519Keyring;
 use sp_runtime::{generic, OpaqueExtrinsic, SaturatedConversion};
@@ -87,7 +87,7 @@ impl ExtrinsicBuilder for TransferKeepAliveBuilder {
 }
 
 /// Generates inherent data for the `benchmark overhead` command.
-pub fn inherent_benchmark_data(config: &Configuration) -> sc_cli::Result<InherentData> {
+pub fn inherent_benchmark_data(_config: &Configuration) -> sc_cli::Result<InherentData> {
     let mut inherent_data = InherentData::new();
 
     let d = Duration::from_millis(0);
@@ -103,10 +103,6 @@ pub fn inherent_benchmark_data(config: &Configuration) -> sc_cli::Result<Inheren
     futures::executor::block_on(slot.provide_inherent_data(&mut inherent_data))
         .map_err(|e| format!("creating slot inherent data: {:?}", e))?;
 
-    let dynamic_fees =
-        pallet_dynamic_fee::InherentDataProvider(U256::from(config.evm.target_gas_price));
-    futures::executor::block_on(dynamic_fees.provide_inherent_data(&mut inherent_data))
-        .map_err(|e| format!("creating dynamic fee inherent data: {:?}", e))?;
     Ok(inherent_data)
 }
 

crates/humanode-peer/src/chain_spec.rs

@@ -368,8 +368,6 @@ fn testnet_genesis(
         },
         evm_accounts_mapping: Default::default(),
         ethereum: EthereumConfig {},
-        dynamic_fee: Default::default(),
-        base_fee: Default::default(),
         transaction_payment: Default::default(),
         fees_pot: Default::default(),
         treasury_pot: Default::default(),

crates/humanode-peer/src/cli/config.rs

@@ -45,13 +45,6 @@ pub trait CliConfigurationExt: SubstrateCliConfigurationProvider {
             }
         });
 
-        let evm = {
-            let params = self.evm_params();
-            configuration::Evm {
-                target_gas_price: params.map(|p| p.target_gas_price).unwrap_or(1),
-            }
-        };
-
         let ethereum_rpc = self
             .ethereum_rpc_params()
             .map(|params| configuration::EthereumRpc {
@@ -77,7 +70,6 @@ pub trait CliConfigurationExt: SubstrateCliConfigurationProvider {
         Ok(Configuration {
             substrate,
             bioauth_flow,
-            evm,
             ethereum_rpc,
             time_warp,
         })

crates/humanode-peer/src/configuration.rs

@@ -18,9 +18,6 @@ pub struct Configuration {
     /// always required.
     pub bioauth_flow: Option<BioauthFlow>,
 
-    /// EVM configuration.
-    pub evm: Evm,
-
     /// Ethereum RPC configuration.
     pub ethereum_rpc: Option<EthereumRpc>,
 
@@ -58,12 +55,6 @@ impl BioauthFlow {
     }
 }
 
-/// EVM configuration parameters.
-pub struct Evm {
-    /// The dynamic-fee pallet target gas price set by block author.
-    pub target_gas_price: u64,
-}
-
 /// Ethereum RPC configuration parameters.
 pub struct EthereumRpc {
     /// Maximum number of blocks to keep the log information available

crates/humanode-peer/src/service/inherents.rs

@@ -2,7 +2,6 @@
 
 use sc_client_api::ProvideUncles;
 use sc_service::Arc;
-use sp_core::U256;
 use sp_runtime::traits::Block;
 
 use crate::time_warp::TimeWarp;
@@ -12,8 +11,6 @@ use crate::time_warp::TimeWarp;
 pub struct Creator<Client> {
     /// Consensus slot duration.
     pub raw_slot_duration: sp_consensus_babe::SlotDuration,
-    /// Ethereum gas target price.
-    pub eth_target_gas_price: u64,
     /// Time warp peer mode.
     pub time_warp: Option<TimeWarp>,
     /// Client.
@@ -25,7 +22,6 @@ pub struct Creator<Client> {
 type InherentDataProviders = (
     sp_consensus_babe::inherents::InherentDataProvider,
     sp_timestamp::InherentDataProvider,
-    pallet_dynamic_fee::InherentDataProvider,
 );
 
 /// The inherents creator for block production.
@@ -63,10 +59,7 @@ where
                 self.0.raw_slot_duration,
             );
 
-        let dynamic_fee =
-            pallet_dynamic_fee::InherentDataProvider(U256::from(self.0.eth_target_gas_price));
-
-        Ok((slot, timestamp, dynamic_fee))
+        Ok((slot, timestamp))
     }
 }
 
@@ -98,18 +91,14 @@ where
                 self.0.raw_slot_duration,
             );
 
-        let dynamic_fee =
-            pallet_dynamic_fee::InherentDataProvider(U256::from(self.0.eth_target_gas_price));
-
-        Ok((slot, timestamp, dynamic_fee))
+        Ok((slot, timestamp))
     }
 }
 
 impl<Client> Clone for Creator<Client> {
     fn clone(&self) -> Self {
         Self {
             raw_slot_duration: self.raw_slot_duration,
-            eth_target_gas_price: self.eth_target_gas_price,
             time_warp: self.time_warp.clone(),
             client: Arc::clone(&self.client),
         }

crates/humanode-peer/src/service/mod.rs

@@ -108,7 +108,6 @@ pub fn new_partial(
 > {
     let Configuration {
         substrate: config,
-        evm: evm_config,
         time_warp: time_warp_config,
         ..
     } = config;
@@ -181,10 +180,8 @@ pub fn new_partial(
     );
 
     let raw_slot_duration = babe_link.config().slot_duration();
-    let eth_target_gas_price = evm_config.target_gas_price;
     let inherent_data_providers_creator = inherents::Creator {
         raw_slot_duration,
-        eth_target_gas_price,
         client: Arc::clone(&client),
         time_warp: time_warp_config.clone(),
     };
@@ -243,7 +240,6 @@ pub async fn new_full(config: Configuration) -> Result<TaskManager, ServiceError
     let Configuration {
         substrate: mut config,
         bioauth_flow: bioauth_flow_config,
-        evm: _evm_config,
         ethereum_rpc: ethereum_rpc_config,
         ..
     } = config;

crates/humanode-runtime/src/constants.rs

@@ -98,3 +98,19 @@ pub mod fees {
     /// The multiplier to get the fee from length.
     pub const LENGTH_TO_FEE: Balance = 1;
 }
+
+/// EVM fees related constants.
+pub mod evm_fees {
+    /// The max amount of gas per block.
+    /// Set to the value that fits our fee requirements.
+    /// Ref: <https://ethereum.org/en/developers/docs/gas/#block-size>
+    pub const BLOCK_GAS_LIMIT: u64 = 60_000_000;
+
+    /// The amount of fee per gas unit.
+    /// Comes from the following rationale:
+    /// - a simple transfer costs 21000 gas
+    /// - we want the cost of this transfer to be around ~0.2 HMND
+    /// - so we must charge about 0.2 * 10^18 / 21000 fee per a unit of gas
+    /// The value below is a nice round number that fits the requirements outlined above.
+    pub const FEE_PER_GAS: u128 = 10_000_000_000_000;
+}

crates/humanode-runtime/src/lib.rs

@@ -5,6 +5,8 @@
 #![allow(missing_docs, clippy::missing_docs_in_private_items)]
 // Either generate code at stadard mode, or `no_std`, based on the `std` feature presence.
 #![cfg_attr(not(feature = "std"), no_std)]
+// Runtime impl macros generate non-snake case names.
+#![allow(non_snake_case)]
 
 // If we're in standard compilation mode, embed the build-script generated code that pulls in
 // the WASM portion of the runtime, so that it is invocable from the native (aka host) side code.
@@ -104,6 +106,7 @@ pub use constants::{
     equivocation::REPORT_LONGEVITY,
     im_online::{MAX_KEYS, MAX_PEER_DATA_ENCODING_SIZE, MAX_PEER_IN_HEARTBEATS},
 };
+use static_assertions::const_assert;
 
 /// An index to a block.
 pub type BlockNumber = u32;
@@ -232,11 +235,14 @@ pub fn native_version() -> NativeVersion {
 const NORMAL_DISPATCH_RATIO: Perbill = Perbill::from_percent(75);
 const MAX_BLOCK_LENGTH: u32 = 5 * 1024 * 1024;
 
+/// We allow for 2 seconds of compute with a 6 second average block time.
+const EXPECTED_BLOCK_WEIGHT: Weight =
+    Weight::from_parts(WEIGHT_REF_TIME_PER_SECOND.saturating_mul(2), u64::MAX);
+
 parameter_types! {
     pub const Version: RuntimeVersion = VERSION;
-    /// We allow for 2 seconds of compute with a 6 second average block time.
     pub BlockWeights: frame_system::limits::BlockWeights = frame_system::limits::BlockWeights
-        ::with_sensible_defaults(Weight::from_parts(WEIGHT_REF_TIME_PER_SECOND.saturating_mul(2), u64::MAX), NORMAL_DISPATCH_RATIO);
+        ::with_sensible_defaults(EXPECTED_BLOCK_WEIGHT, NORMAL_DISPATCH_RATIO);
     pub BlockLength: frame_system::limits::BlockLength = frame_system::limits::BlockLength
         ::max_with_normal_ratio(MAX_BLOCK_LENGTH, NORMAL_DISPATCH_RATIO);
     pub SS58Prefix: u16 = ChainProperties::ss58_prefix();
@@ -624,13 +630,19 @@ impl pallet_offences::Config for Runtime {
     type OnOffenceHandler = OffenceSlasher;
 }
 
-const BLOCK_GAS_LIMIT: u64 = 75_000_000;
-const WEIGHT_MILLISECS_PER_BLOCK: u64 = 2000;
+const WEIGHT_MILLISECS_PER_BLOCK: u64 = EXPECTED_BLOCK_WEIGHT.ref_time()
+    / frame_support::weights::constants::WEIGHT_REF_TIME_PER_MILLIS;
+// An assertion to ensure this value is what we expect it to be here.
+const_assert!(WEIGHT_MILLISECS_PER_BLOCK == 2000u64);
 
 parameter_types! {
-    pub BlockGasLimit: U256 = U256::from(BLOCK_GAS_LIMIT);
+    pub BlockGasLimit: U256 = U256::from(constants::evm_fees::BLOCK_GAS_LIMIT);
     pub PrecompilesValue: FrontierPrecompiles<Runtime> = FrontierPrecompiles::<_>::default();
-    pub WeightPerGas: Weight = Weight::from_ref_time(fp_evm::weight_per_gas(BLOCK_GAS_LIMIT, NORMAL_DISPATCH_RATIO, WEIGHT_MILLISECS_PER_BLOCK));
+    pub WeightPerGas: Weight = Weight::from_ref_time(fp_evm::weight_per_gas(
+        constants::evm_fees::BLOCK_GAS_LIMIT,
+        NORMAL_DISPATCH_RATIO,
+        WEIGHT_MILLISECS_PER_BLOCK,
+    ));
 }
 
 impl pallet_evm_system::Config for Runtime {
@@ -658,9 +670,18 @@ impl pallet_currency_swap::Config for Runtime {
     type WeightInfo = ();
 }
 
+/// A simple fixed fee per gas calculator.
+pub struct EvmFeePerGas;
+
+impl fp_evm::FeeCalculator for EvmFeePerGas {
+    fn min_gas_price() -> (U256, Weight) {
+        (constants::evm_fees::FEE_PER_GAS.into(), Weight::zero())
+    }
+}
+
 impl pallet_evm::Config for Runtime {
     type AccountProvider = EvmSystem;
-    type FeeCalculator = BaseFee;
+    type FeeCalculator = EvmFeePerGas;
     type GasWeightMapping = pallet_evm::FixedGasWeightMapping<Self>;
     type WeightPerGas = WeightPerGas;
     type BlockHashMapping = pallet_ethereum::EthereumBlockHashMapping<Self>;
@@ -692,39 +713,6 @@ impl pallet_ethereum::Config for Runtime {
     type PostLogContent = PostBlockAndTxnHashes;
 }
 
-parameter_types! {
-    pub BoundDivision: U256 = U256::from(1024);
-}
-
-impl pallet_dynamic_fee::Config for Runtime {
-    type MinGasPriceBoundDivisor = BoundDivision;
-}
-
-parameter_types! {
-    pub DefaultBaseFeePerGas: U256 = U256::from(1_000_000_000);
-    pub DefaultElasticity: Permill = Permill::from_parts(125_000);
-}
-
-pub struct BaseFeeThreshold;
-impl pallet_base_fee::BaseFeeThreshold for BaseFeeThreshold {
-    fn lower() -> Permill {
-        Permill::zero()
-    }
-    fn ideal() -> Permill {
-        Permill::from_parts(500_000)
-    }
-    fn upper() -> Permill {
-        Permill::from_parts(1_000_000)
-    }
-}
-
-impl pallet_base_fee::Config for Runtime {
-    type RuntimeEvent = RuntimeEvent;
-    type Threshold = BaseFeeThreshold;
-    type DefaultBaseFeePerGas = DefaultBaseFeePerGas;
-    type DefaultElasticity = DefaultElasticity;
-}
-
 impl pallet_chain_properties::Config for Runtime {}
 
 impl pallet_ethereum_chain_id::Config for Runtime {}
@@ -832,8 +820,6 @@ construct_runtime!(
         Grandpa: pallet_grandpa = 20,
         Ethereum: pallet_ethereum = 21,
         EVM: pallet_evm = 22,
-        DynamicFee: pallet_dynamic_fee = 23,
-        BaseFee: pallet_base_fee = 24,
         ImOnline: pallet_im_online = 25,
         EvmAccountsMapping: pallet_evm_accounts_mapping = 26,
         TokenClaims: pallet_token_claims = 27,
@@ -1394,7 +1380,7 @@ impl_runtime_apis! {
         }
 
         fn elasticity() -> Option<Permill> {
-            Some(BaseFee::elasticity())
+            None
         }
 
         fn gas_limit_multiplier_support() {}

crates/humanode-runtime/src/tests/claims_and_vesting.rs

@@ -329,14 +329,6 @@ fn prepare_genesis_json(token_claims: &str, token_claim_pot_balance: u128) -> St
                 }}
             }}
         }},
-        "dynamicFee": {{
-            "minGasPrice": "0x0"
-        }},
-        "baseFee": {{
-            "baseFeePerGas": "0x0",
-            "elasticity": 0,
-            "marker": null
-        }},
         "imOnline": {{
             "keys": []
         }},

crates/humanode-runtime/src/tests/currency_swap.rs

@@ -12,7 +12,8 @@ use crate::dev_utils::*;
 use crate::opaque::SessionKeys;
 
 pub(crate) static PRECOMPILE_ADDRESS: Lazy<H160> = Lazy::new(|| H160::from_low_u64_be(0x900));
-pub(crate) static GAS_PRICE: Lazy<U256> = Lazy::new(|| 1_000_000_000u128.into());
+pub(crate) static GAS_PRICE: Lazy<U256> =
+    Lazy::new(|| <Runtime as pallet_evm::Config>::FeeCalculator::min_gas_price().0);
 
 const INIT_BALANCE: Balance = 10u128.pow(18 + 6);