What is the Ethereum Virtual Machine (EVM)?
The Ethereum Virtual Machine (EVM) is the cornerstone of the Ethereum blockchain and the core engine for running smart contracts and decentralized applications (dApps). It is not a physical server, but a virtual environment running on thousands of Ethereum nodes worldwide. The EVM ensures that all code deployed on it executes according to predefined logic, free from censorship and tampering, thereby building a trusted computing platform.
- Core Definition and Operating Mechanism: The EVM is essentially a distributed computing platform responsible for deploying and executing smart contracts across the entire Ethereum network. It enables the entire Ethereum network to transition smoothly from one state to the next with the generation of each new block, thus often being regarded as a "state machine."
- Gas Mechanism: To prevent malicious behaviors like infinite loops and to incentivize developers to optimize code efficiency, the EVM introduced the "Gas" mechanism. Each operation consumes a certain amount of Gas, which is a unit measuring the consumption of computational resources. Even if a transaction fails during execution due to insufficient Gas, the consumed Gas must still be paid.
- Smart Contracts: Smart contracts are codes specifically designed for the EVM, and once deployed, they cannot be altered. They define how states are created, modified, and stored in decentralized applications, serving as the core vehicle for the EVM to fulfill its functions.
- EVM Compatibility: The EVM's influence extends far beyond Ethereum itself. Many emerging Layer-1 blockchains, such as Polygon, Arbitrum, Avalanche, and BNB Chain, have chosen to be EVM-compatible. This strategy allows them to easily access the vast Ethereum developer community and user base, promoting broader ecosystem interoperability.
What are the shortcomings of the Ethereum Virtual Machine?
Despite the EVM's immense success in the blockchain space, its inherent design also introduces certain limitations that restrict the performance and user experience of the Ethereum network. For related developments, please refer to Svmuu's ongoing reports.
Low Execution Efficiency
- Single-threaded Architecture: The EVM adopts a line-by-line interpretive execution method, where each instruction needs to be processed individually. This results in execution speeds far slower than next-generation parallel virtual machines like Solana's Sealevel or Aptos's Move VM, severely limiting the network's transaction throughput.
- 256-bit Integer Operations: For specific reasons, the EVM uses non-mainstream 256-bit integers. Compared to processor-native 8, 16, 32, and 64-bit integers, 256-bit operations are more complex, leading to overall inefficient computation.
- High Gas Fees and Network Congestion: With the surge in users and transaction volume on the Ethereum mainnet, network congestion and high Gas fees have become increasingly prominent issues. Ethereum currently processes approximately 15 transactions per second (TPS), which struggles to meet the growing global transaction demand.
- Inefficient Data Structures: While simple, the EVM's data structures perform mediocrely in terms of efficiency. The overhead for accessing and storing states is high, and smart contracts often encounter performance bottlenecks during complex interactions.
Poor Development and Debugging Experience
- Lack of Standard Library Support: When developing on the EVM using languages like Solidity, developers often face the dilemma of lacking comprehensive standard library support. This means many basic functionalities (such as string concatenation and splitting) need to be implemented by developers themselves, which not only increases development difficulty but also may introduce security vulnerabilities and unnecessary Gas consumption.
- Difficult Debugging and Testing: The EVM's debugging tools are relatively limited, with the only exception usually being
OutOfGas. It lacks debugging logs and cannot directly call external code or perform breakpoint debugging. While theeventmechanism can improve this situation to some extent, it is not an ideal debugging tool. - No Floating-Point Support: The EVM only supports integer operations (with Wei as the smallest unit) and does not support floating-point numbers. This constitutes a significant limitation in scenarios requiring approximate values or complex mathematical calculations, such as risk modeling and scientific computing.
Smart Contract Management Limitations
- Immutable Code / Difficult to Upgrade: Once a smart contract is deployed on the EVM, its code is completely immutable. Because the EVM uses a Harvard computer architecture, code and data are completely separated and cannot be loaded and executed in memory. This means that contract upgrades can only be achieved by deploying new contracts and migrating data, a time-consuming and labor-intensive process.
- Inflexible Memory Management: There is no direct mechanism for freeing memory in the EVM. Furthermore, the Gas consumption for allocating memory is not linear, which increases the cost and complexity of ensuring memory safety.
Other Shortcomings
- Lack of Resource Management and Complex Permission Control: The EVM itself does not provide built-in resource management or complex permission control functionalities. Developers are forced to write their own contract logic to compensate for these deficiencies, thereby increasing development complexity and the potential for introducing errors.
- Poor Compatibility with New Cryptographic Schemes: If the EVM does not natively support emerging cryptographic schemes such as quantum-safe signatures or zero-knowledge proofs, or lacks corresponding precompiled contracts, on-chain verification of these signatures would consume a very large amount of Gas, severely impacting the scalability and practical application of these schemes.
