[Constitutional] AIP: Activate ArbOS 51 (Dia) and Gas Pricing Updates

Type: Constitutional AIP

Abstract

This AIP proposes the activation of ArbOS 51: Dia on Arbitrum One and Arbitrum Nova as well as increases to the gas target and min L2 base fee, along with changes to the L2 pricing algorithm. This on-chain vote proposes to bundle together the following two temperature check votes:

1. AIP: ArbOS 51 Version 51 Dia: which contains relevant Fusaka EIPs, the addition of a MaxTxGasLimit allowing full block utilization, changes to instrument Nitro’s State Transition Function (STF) to price gas based on specific resource usage, native token mint/burn capabilities, and a few bug fixes. 
2. AIP: Raise the gas target, implement improvements to the pricing algorithm, and raise the L2 min base fee

The combination of ArbOS 51 and the gas-target/pricing updates will ship as a single integrated release, designated ArbOS 51, which supersedes the originally planned standalone activation of ArbOS 50.

Since the ArbitrumDAO has already signaled support for the adoption of the above two AIPs in their respective temperature check votes, this on-chain vote will bundle both of these AIPs for activation on Arbitrum One and Arbitrum Nova with the ArbOS 51 release. Please visit the forum posts for each of the AIPs to learn more.

The ArbOS 51 release builds upon ArbOS 40 Callisto and will be shipped as a new mandatory Nitro release and new versions of the rollup contracts for Arbitrum One and Arbitrum Nova, should the ArbitrumDAO vote to pass this proposal. This proposal increments the ArbOS version number to 5x instead of 4x due to technical details that allow for better Orbit chain customizability, as explained here.

This proposal only concerns the Arbitrum One and Arbitrum Nova chains, as these two chains are governed by the ArbitrumDAO. On a high level, an ArbOS upgrade can be interpreted as Arbitrum’s equivalent of a hard fork - more can be read about the subject here.

Changes Included

1.   Activation of ArbOS 51 Dia

ArbOS 51 Dia enables full Fusaka compatibility while introducing native Arbitrum improvements. Visit the original Forum Post to read more details about the proposed changes. Key components include of this ArbOS 51 release include:

• EIP-7951: Precompile for secp256r1 Curve Support
• EIP-7825: Transaction Gas Limit Cap
• EIP-7642: eth/69 - history expiry and simpler receipts
• EIP-7939: Count leading zeros (CLZ) opcode
• EIP-7823: Set upper bounds for MODEXP
• EIP-7883: ModExp Gas Cost Increase
• EIP-7910: eth_config JSON-RPC Method
• Enable EIP-2537: Precompile for BLS12-381 curve operations
• Introduce an “Effective Block Gas Limit” in the STF, with a MaxTxGasLimit of 32M gas. The total Effective Block Gas Limit becomes 64M gas (MaxTxGasLimit + MaxBlockGasLimit). This doesn’t change the GasTarget or overall gas per second, only how gas is distributed across blocks.
• Instrumentation of the State Transition Function (STF) to track transaction gas consumption across multiple resource types, rather than a single total based on opcodes, including: computation, storage growth, storage access, history growth, and calldata. This work lays the foundation for dynamic, resource-based pricing where fees can adjust based on the most constrained resource on the network and represent one part of Arbitrum’s scaling strategy for lower, more stable fees as demand grows.This explainer blog and Vitalik’s post on Multidimensional gas pricing are great resources to learn more about this approach to improving how the EVM prices network resource usage.
• Native token mint/burn to allow an Arbitrum chain to delegate minting and burning of its native gas token to a trusted bridge provider. Native Token Mint/Burn is proposed to be included in ArbOS 51 Dia for the benefit of Arbitrum Orbit chains (reducing the need for forks) and to streamline development and testing into a single codebase. There are no plans to enable this feature on Arbitrum One or Arbitrum Nova,**** consequently this feature will be explicitly left disabled for Arbitrum One and Arbitrum Nova. To read more about this feature, go here.
• A number of bug fixes, including:
  • Standardization of how compressed batch calldata gas units are calculated
  • A fix to address a divergence in EIP-7702 precompile delegation behavior
  • An update to address a Stylus-related bug that caused a divergence on Arbitrum Sepolia. More details on this incident can be found here.

The below list of Fusaka-related EIPs are not proposed to be included or supported in ArbOS 51 Dia. Visit the original Forum Post to read more details about these EIPs and our decision not to propose them for inclusion in ArbOS 51:

• EIP-7594, EIP-7918, and EIP-7892: Arbitrum chains do not have blob data markets, nor do they support posting blob data to a non-Arbitrum parent chain
• EIP-7917: Arbitrum chains do not have a beacon chain, and therefore, do not have a peer-to-peer layer like Ethereum does
• EIP-7934: Arbitrum does not propagate blocks between nodes
• EIP-7935: Arbitrum blocks are built differently from those on Ethereum, with different assumptions and mechanics. Therefore, an increase in Ethereum block’s size limit does not need to be replicated or matched with an increase in Arbitrum block size limit.

2.   Raising the gas target, increasing the min L2 base fee, & improving the pricing algorithm

As part of our strategy for scaling Arbitrum technology, this proposal includes the AIP to improve the pricing algorithm for Arbitrum One and Nova to reduce the severity, frequency, and duration of high L2 gas prices during periods of elevated demand on the network. Concretely, the proposed changes are to:

• Replace the current single gas target and single adjustment window, with a new model that employs multiple (higher) gas targets, measured over multiple adjustment windows,
• Raise the long term effective gas target, up from today’s single gas target of 7 Mgas/s (up to a maximum of 100 Mgas/s),
• Grant Offchain Labs, in its role as an Arbitrum Aligned Entity, the permission to make additional changes gradually to scale the chain sustainably, and
• Increase the minimum L2 base fee from 0.01 gwei per gas to 0.02 gwei per gas.

The rationale for this change, alongside details on the specifications and supporting data, can be found here in the original AIP.

Implementation Details

All of the above changes are implemented in a release of Arbitrum Nitro and will be shipped via two separate upgrades: a Nitro node version upgrade and an update with the on-chain rollup contracts on Arbitrum One and Arbitrum Nova. Should this proposal pass, the payload will be executed on-chain and will include the relevant on-chain contract changes, updating the WASM module root, and scheduling of the ArbOS upgrade. The proposed payload changes assume that the Nitro node software for all

... please visit link below to view full proposal

https://tally.xyz/gov/arbitrum/proposal/53154361738756237993090798888616593723057470462495169047773178676976253908001