Firedancer Proposes Removing Solana’s Block Limit to Boost Speed

Jump Crypto’s Firedancer team has submitted a proposal that could change how Solana processes transactions.

The plan, known as SIMD-0370, wants to remove the network’s fixed block limit and let validators process as many transactions as their hardware can handle.

This proposal comes at a time when Solana is preparing for its biggest upgrade yet. The blockchain recently saw overwhelming support for the Alpenglow upgrade, which passed with 98.27% approval from validators in early September 2025.

Understanding the Current Block Limit

Right now, Solana has a fixed limit of 60 million compute units per block. This means every validator faces the same ceiling, no matter how powerful their computer systems are. An earlier proposal called SIMD-0286 suggested raising this limit to 100 million compute units.

But Firedancer’s team argues this approach doesn’t make sense anymore. They say artificial caps prevent the network from using its full potential. Instead of manually adjusting limits through community votes, they want the network to scale automatically based on what validators can actually handle.

The proposal would work alongside the Alpenglow upgrade, which is scheduled for testnet deployment in December 2025. Alpenglow will reduce transaction finality from about 12.8 seconds to just 100-150 milliseconds—making Solana nearly 100 times faster than it is today.

How the New System Would Work

Under SIMD-0370, block producers could pack as many transactions into a block as their systems can process. Validators running slower hardware would simply skip blocks that are too complex for them to handle in time. The blockchain would keep running without disruption.

Source: @solana_devs

This creates what Anza, a Solana development company, calls a “performance flywheel.” Block producers would compete to pack more transactions and earn higher fees. Validators that frequently skip blocks would lose rewards, pushing them to upgrade their hardware or optimize their software. As more validators improve their performance, block producers can safely push limits even further.

The system relies on market forces rather than fixed rules. Validators with better equipment would capture more rewards, creating financial incentives for continuous improvement across the network.

The Alpenglow Connection

The SIMD-0370 proposal depends heavily on Alpenglow’s new features. The upgrade introduces a “skip-vote” mechanism that lets validators automatically abstain from voting on blocks they can’t process quickly enough. This prevents slower validators from holding up the entire network.

Alpenglow also brings two new components called Votor and Rotor, which replace Solana’s current Proof-of-History and Tower BFT systems. These changes form the foundation that makes removing block limits possible without breaking consensus.

The Firedancer client itself has already shown impressive results in testing, processing over 1 million transactions per second. Written in C++ for maximum efficiency, it offers an independent implementation that strengthens network security by reducing reliance on a single validator client.

Concerns About Centralization

Not everyone supports the proposal. Some developers worry it could make the network more centralized over time.

Engineer Akhilesh Singhania raised concerns on the GitHub discussion, warning that bigger validators with deep pockets could keep upgrading to more expensive hardware. This might force smaller validators who can’t afford constant upgrades to drop out entirely, leaving fewer large validators controlling the network.

Roger Wattenhoffer, head of research at Anza, also cautioned that removing block limits could introduce technical risks. He noted these problems might be solvable but require careful consideration.

Geographic location could become another advantage. Validators positioned closer to block producers would start executing transactions earlier, giving them a competitive edge that has nothing to do with hardware quality.

Critics also point out that if blocks grow too large too quickly, the peer-to-peer network might struggle to propagate them efficiently. This could lead to temporary forks or missed votes, potentially destabilizing the network during periods of rapid growth.

What This Means for Solana’s Future

If implemented, SIMD-0370 would mark a shift from centrally-planned capacity limits to market-driven scaling. The change aligns with Solana’s goal of becoming one of the fastest blockchains in the world, capable of competing with traditional internet infrastructure.

The proposal comes as institutional interest in Solana grows. Multiple asset managers including Franklin Templeton and Fidelity have filed for Solana ETFs, with analysts predicting approval decisions could arrive by mid-October 2025. Market analysts project these investment products could bring $3-6 billion in institutional capital to the ecosystem.

Solana’s price jumped 3.5% to $210.58 in the 24 hours following the proposal announcement, reflecting positive market sentiment about the network’s technical direction.

The SIMD-0370 proposal is currently in the review phase. The Solana community will need to evaluate whether the performance benefits outweigh the centralization risks before moving forward with implementation.

Firedancer launched on Solana’s mainnet in limited capacity in September 2024 as “Frankendancer,” a hybrid version. The client’s phased rollout continues as it works toward full deployment, with the goal of improving client diversity across the validator network.

The Road Ahead

The proposal represents an ambitious attempt to remove artificial constraints on Solana’s growth. Rather than periodically voting to raise block limits, the network would let validator capabilities determine capacity automatically.

Testing will be critical before any mainnet deployment. The community must verify that the skip-vote mechanism works reliably across different validator configurations and that networking infrastructure can handle variable block sizes without performance degradation.

The Alpenglow testnet launch in December will provide the first real-world data on how these systems perform together. If successful, mainnet activation is planned for Q1 2026, with SIMD-0370 potentially following after Alpenglow stabilizes.

Balance remains the key challenge. Solana needs to preserve its decentralized validator set while unlocking the performance gains that removing block limits would provide. How the community navigates this tradeoff will shape the blockchain’s future competitiveness in the layer-1 space.