EVM: The core component of Ethereum

The EVM is the core of Ethereum, responsible for executing smart contracts and processing transactions. Unlike the virtualization of real computers, the EVM is a specialized computing engine that provides abstraction for computation and storage. It executes its own bytecode instruction set, typically compiled from Solidity.

EVM is a quasi-Turing complete state machine. The reason for “quasi” is that all execution steps consume a limited amount of Gas resources, which limits the number of execution steps of the smart contracts, avoiding the situation where a possible infinite loop would cause the entire platform to stop.

The EVM does not have scheduling capabilities, but instead executes the transactions in the block sequentially. This process modifies the world state, with state accumulation after each transaction execution. Since the execution of the next block strictly depends on the final state of the previous block, the linear execution process of Ethereum transactions is difficult to optimize in parallel.

This sequential execution, while ensuring security, may lead to network congestion and delays under high load conditions, which is one of the reasons why Ethereum needs Layer2 Rollup scaling.

High-performance Layer 1 Parallel Strategy

Most high-performance Layer 1s have designed optimization solutions to address Ethereum’s inability to handle parallel processing, primarily focusing on virtual machine selection and parallel execution.

Virtual Machine Selection

High-performance Layer 1s are more likely to use virtual machines based on WASM, eBPF bytecode, or Move bytecode, rather than EVM.

WASM is a small, fast-loading, portable, and secure bytecode format that supports multiple programming languages. Many blockchain projects have adopted it as a standard, and Ethereum also plans to integrate WASM in the future.

eBPF originated from network packet filtering technology and later developed into a technology that allows for dynamic modification of the operating system kernel without altering the source code. Some blockchain networks use eBPF-based bytecode to run smart contracts.

Move is a smart contract programming language that emphasizes security and verifiability, aiming to address security issues in assets and transactions. Some emerging blockchain projects have adopted Move or its customized versions to write smart contracts.

Parallel Execution

Parallel execution in blockchain means processing unrelated transactions simultaneously. The main challenge in achieving parallel execution is determining which transactions are independent. High-performance Layer 1 primarily relies on two methods: state access methods and optimistic parallel models.

The state access method requires prior knowledge of which part of the blockchain state each transaction can access, in order to analyze which transactions are independent.

The optimistic parallel model assumes that all transactions are independent, validating this assumption after execution and adjusting if necessary.

The Development of Parallel EVM

The concept of parallel EVM was proposed as early as 2021, originally referring to an EVM that supports the simultaneous processing of multiple transactions. Recently, this concept has gained renewed attention, driving the development of EVM-compatible Layer 1s that adopt parallel execution technology.

The reasonably defined parallel EVM mainly includes three categories:

1. Existing EVM-compatible Layer 1 parallel execution upgrade
2. The new EVM-compatible Layer 1 using parallel execution technology
3. EVM-compatible solutions on non-EVM compatible Layer 1

Some emerging projects are exploring these directions, such as Monand, Sei V2, Artela, and Solana Neon. These projects adopt different parallel execution strategies aimed at improving transaction processing efficiency and network performance.

Outlook

The parallel technology of blockchain is an ongoing topic of development. Currently, most solutions are modifications and imitations of optimistic execution models, with no substantial breakthroughs yet.

In the future, there may be more emerging Layer 1 projects joining the competition for parallel EVM, and existing Layer 1s may also achieve EVM parallel upgrades or EVM-compatible solutions. Although these two directions have different paths, they are both committed to improving performance.

In addition to high-performance EVM, the diversified development of blockchain technology is also worth looking forward to, as new virtual machine technologies such as WASM, SVM, and Move VM may bring new development opportunities.