Introduction
The latest release of EOS EVM introduces support for Shanghai and London Hard Fork and their comprised features, a new gas fee algorithm to more accurately price transactions for underlying resource costs involved, and configuration settings to adjust the base token of the network.
Read on for more details.
New features
London Fork Compatibility
EIP-1559: Transaction Fee Reform
PRs
A critical component of the London Hard Fork is EIP-1559, which introduces a new transaction fee mechanism. This update changes how gas fees are handled on the EOS EVM network with new components including a base fee and priority fee combined to calculate the overall cost of a transaction based on units of gas used.
Base fee
The base fee, implemented as the base_fee_per_gas, is the minimum fee required for a transaction to be included in a block. This fee is burned in the Ethereum implementation, but is instead credited to the contract for EOS EVM. The base_fee_per_gas is now part of the block header information and is returned in both eth_getBlockByNumber and eth_getBlockByHash API calls.
Priority fee
The priority fee, implemented as the inclusion_price, is a fee historically designed so that users can pay to miners to incentivize them to prioritize their transactions over others. In EOS EVM, the priority fee does not prioritize transactions. Instead, it is a fee set by the miner to cover their costs for processing the transaction and pushing it into the network. This fee goes directly to the miner and is not burned.
The priority fee or inclusion_price can be calculated as min(max_priority_fee_per_gas, max_fee_per_gas - base_fee_per_gas).
Max fee
Users may now specify a maximum fee they are willing to pay for the sum of base and priority fees. If the max fee is higher than the sum of the base fee and the priority fee, the difference is refunded to the user. This ensures users don't overpay beyond what is necessary to get their transactions processed.
Overall transaction fee
The overall cost of a transaction fee utilizes a price per gas unit implemented as the effective_gas_price, which can be calculated as
inclusion_price + base_fee_per_gas. The overall cost of any given transaction is then calculated as the product ofeffective_gas_price * gas_used.
Fee distribution
The fees associated with transactions are now distributed to where the contract receives base_fee_per_gas*gas_used and the miner receives inclusion_price*gas_used.
Feature activation for wallet users
The flag for the EIP-1559 network support is cached, so users will have to refresh their network selection by changing the active network to another network and go back to eos-evm in order for many common wallets like Metamask to start sending EIP-1559 transactions.
Shanghai Fork Compatibility
PUSH0 Opcode Support
Support has been added for the PUSH0 opcode as introduced in the Shanghai Hard Fork. This opcode pushes a zero onto the stack, optimizing certain types of smart contract code and potentially reducing gas costs for operations that frequently use zero values.
Gas Fee Algorithm Enhancements
PRs
A new gas fee algorithm has been introduced to alleviate challenges with a prior one-size-fits-all gas fee structure. Because the previous method used to calculate gas fees did not account for the varying computational resources required by transactions, many transactions were priced higher than their resource costs for the safety of the network.
To accomplish this, five new parameters are now tracked including:
- Additional gas consumed when creating a new non-contract account due to a message-call transaction that sends positive value to an empty account. This value defaults to 0 and is denoted as
G_txnewaccount. - Additional gas consumed when creating a new non-contract account due to the
CALLorSELFDESTRUCTopcodes. This value defaults to to 25000 and is denoted asG_newaccount. - Static gas consumed in the
CREATEandCREATE2opcodes and also acts as the additional gas consumed in a contract-creating transaction. This value defaults to 32000 and is denotedG_txcreate. - Factor that multiplies the deployed code size within
CREATEandCREATE2opcodes, as well as contract-creating transactions, to determine the code deposit cost. This value defaults to 200 and is denoted asG_codedeposit. - Gas consumed when an
SSTOREopcode causes the storage value to go from zero to non-zero. This value defaults to 20000 and is denoted asG_sset.
These five new parameters can be calculated as follows:
G_txnewaccount=account_bytes * gas_per_byteG_newaccount=account_bytes * gas_per_byteG_txcreate=contract_fixed_bytes * gas_per_byteG_codedeposit=gas_per_byteG_sset= 2900 +storage_slot_bytes * gas_per_byte
Each of these five parameters are accounted for an stored when establishing an updated gas cost.
Configurable Base Token
EOS EVM now has the ability to be deployed with a different base token for fees and a different chain id as a configuration setting. This enables other EVM instances to exist that utilize other ecosystem tokens, such as BTC for exSat.
General Hard Fork Solution
EOS EVM now officially supports multiple versions and the ability to perform a hard forks when required for future versions such as London Hard Fork detailed above.
This release implements a linear versioning system for EOS EVM hard forks, mapping each EOSEVM version to a corresponding EVMC revision:
| EOSEVM Version | EVMC Revision |
|---|---|
| 0 | ISTANBUL |
| 1 | SHANGHAI |
Note: for this release, EOS EVM is moving directly from Instanbul to Shanghai, including all support for London Hard Fork within that version.
Bug fixes
Allow transfer of non-EOS tokens out of contract account
PRs
Previously, only EOS was capable of being moved out of the contract account in order to be utilized for operational costs. Recent updates now allow other token types to be transferred out of the account.
Building, compatibility, and upgrading
Building
The README in the eos-evm repository contains instructions on how to build EOS EVM Contract.
Compatibility and upgrading
EOS EVM Contract can be upgraded from the prior 0.6.0 version by simply deploying the WASM and ABI.
Further details on changes since last release
Contributors
Special thanks to the contributors that submitted patches for this release:
Full list of changes since last release
PRs
- (665)[0.6 -> main] Bump 0.6.0 version
- (667) fix unittest compile error, explicitly set inline action size to 4kB
- (675) [0.6] Allow transfer non-EOS tokens out.
- (676) [0.6->main] Allow transfer non-EOS tokens out
- (665) [0.6 -> main] Bump 0.6.0 version
- (667) fix unittest compile error, explicitly set inline action size to 4kB
- (675) [0.6] Allow transfer non-EOS tokens out.
- (676) [0.6->main] Allow transfer non-EOS tokens out
- (677) Add support for EOSEVM version
- (681) use libtester 5.0 in CI; use ubuntu 22.04 for CI; use EOS VM OC for tests
- (682) gas param config change event
- (687) Remove silkworm copy in tests
- (692) Use active gas parameters in ExecutionState
- (698) Remove minimum_gas_price from consensus parameters
- (699) use base_fee_per_gas for exec a trx
- (701) Update behavior when changing gas-price
- (702) Kayan min inclusion price
- (703) Fix base-fee change on EVM block boundary
- (704) Change miner portion calculation
- (705) Allow decoding of dynamic fee transactions generated by Metamask
- (707) dynamically support different base token via init
- (709) Use Shanghai consensus tests
- (710) Add queue front block in runtime configuration
- (712) Update silkworm to use Shanghai for version=1
- (713)[1.0] Bump 1.0.0-rc1 version
- (718)[1.0] Make gas_limit dynamic in handle_evm_transfer
- (723)[1.0 -> main] Bump 1.0.0-rc2 version
- (727)[1.0] Update silkworm 1.0.1
- (726)[1.0] Restrict rlp formats when decoding transaction
- (733)[1.0] Check ingress fee precision
- (742)Update silkworm 1.0.2
- (745)[1.0] Bump 1.0.0-rc4 version
- (753) [1.0] fix ci by using new upload script.
- (751) [1.0] dynamic chainid
- (757) [1.0] Kayan 1.0 spring
- (762) [1.0] Bump 1.0.0 version
Full Changelog: v0.6.0...v1.0.0
