[FIP-01] Fuel Improvement Proposal: Enhanced Parallelism and Developer Experience

Title: Fuel Improvement Proposal: Optimizing Parallelism and Enhancing Developer Tools
Author: Pintea, Tudor

1. Abstract

This proposal outlines a comprehensive strategy to optimize Fuel’s parallel transaction execution capabilities and enhance the developer experience through improvements to the Fuel Virtual Machine (FuelVM) and the Sway language toolchain.

2. Motivation

Fuel’s ability to execute transactions in parallel is a key differentiator in the blockchain space. To maintain and extend this lead, we propose targeted optimizations to the UTXO model and enhancements to the developer toolchain, including the FuelVM and Sway language.

3. Background

Fuel leverages a UTXO model to enable parallel transaction execution, which is instrumental in achieving high throughput. The FuelVM is designed for efficiency, and Sway, a domain-specific language, is tailored for smart contract development with a toolchain called Forc.

4. Specification

4.1 Parallelism Optimization

4.1.1 Scheduling Algorithm Enhancement

We propose the integration of a lock-free concurrent scheduling algorithm that can manage dependencies between UTXOs more efficiently. This could be based on existing models such as the work-stealing algorithm used in modern concurrent programming languages.


// Pseudo-Rust code for a work-stealing UTXO scheduler
fn process_transactions(tx_pool: &TransactionPool) {
    let workers = create_workers(cpu_cores::get());

    for tx in tx_pool.iter() {

    while let Some(worker) = workers.steal() {

4.1.2 State Access List Optimization

Introduce a dynamic analysis tool that can pre-calculate the state access patterns of transactions to optimize the UTXO list for better parallel execution.


# Pseudo-code for state access pattern analysis
def analyze_access_patterns(transactions):
    access_list = defaultdict(list)

    for tx in transactions:
        reads, writes = tx.get_access_lists()

    return optimize_access_list(access_list)

4.2 FuelVM Enhancements

4.2.1 Opcode Optimization

Review and optimize the set of opcodes in FuelVM to eliminate redundancies and introduce new opcodes that can perform multiple actions atomically.


; Before optimization

; After optimization
PUSH 1 2

4.2.2 FuelVM JIT Compiler

Develop a Just-In-Time (JIT) compiler for the FuelVM to improve the execution speed of smart contracts.


// Pseudo-C code for a simple JIT compiler function
void* jit_compile(fuel_opcode_t* opcodes, size_t num_opcodes) {
    // Translate FuelVM opcodes to machine code

4.3 Sway Language and Forc Toolchain Development

4.3.1 Advanced Language Features

Incorporate advanced language features into Sway, such as generics and async/await patterns, drawing inspiration from Rust.


// Pseudo-Sway code demonstrating generics
contract<T> MyContract {
    fn new(value: T) -> Self {
        // Implementation

4.3.2 Forc Toolchain Improvements

Enhance the Forc toolchain with better package management, debugging tools, and integration with popular IDEs.


# Forc package management CLI
forc install my-package
forc update

5. Rationale

The proposed enhancements are expected to significantly improve the throughput and developer experience on the Fuel platform. By optimizing the parallel execution model and enhancing the developer toolchain, Fuel can attract more developers and projects, thereby growing the ecosystem.

6. Backward Compatibility

All changes will be implemented with strict adherence to backward compatibility principles, ensuring that existing contracts and applications continue to function without modification.

7. Test Cases

Comprehensive benchmarks and test suites will be developed to measure the performance impact of the proposed optimizations and ensure the reliability of the FuelVM and Sway toolchain updates.

8. Implementation

The proposal will be implemented in phases, with community feedback loops integrated into each phase to ensure alignment with user and developer needs.

9. Security Considerations

Security audits will be conducted at each stage of implementation to ensure that optimizations do not compromise the integrity of the Fuel blockchain.

10. References

11. Conclusion

The adoption of this proposal will ensure that Fuel remains at the forefront of blockchain scalability and usability, providing a robust platform for the next generation of decentralized applications.


Thank you for the detailed proposal!

I’m the team-lead of the tooling team and just wanting to let you know that the features you suggest in 4.3.2 Forc Toolchain Improvements are actively being considered at the moment.

Hopefully we will have debugging support and a package manager ready in Q1 next year.


I want to honestly say a lot of research has gone into this proposal and I am certain the team will definitely look into it.

Sway language is rapidly gaining traction in the broader ecosystem.

Thanks for the very detailed proposal.

Regarding parallelism, we do have that planned in future releases. We are currently focused on optimizing per core, vs over many cores at the moment.

The static analysis approach is exactly what is planned in regard to parallel processing.

JIT for the compiler has been considered, but we want to focus on making Sway the best possible language it can be first before we do that.

Toolchain package installation is on the way, so stay tuned for that.