EIP-7691

EIP-7691¶

Overview¶

EIP-7691 (Blob Throughput Increase) is part of Ethereum's Pectra upgrade, proposing to increase the number of blobs per block from the current target of 3 / maximum of 6 to a target of 6 / maximum of 9. This proposal aims to increase Ethereum's data availability throughput, providing more block space for Layer 2 rollups.

This proposal is a follow-up optimization to EIP-4844 (Dencun upgrade), further expanding blob capacity after verifying network stability.

Background¶

Success of the Dencun Upgrade The Dencun upgrade in March 2024 introduced blob transactions (EIP-4844), setting: - Target blob count: 3 per block - Maximum blob count: 6 per block

After months of monitoring, the network performed well: - Good network stability - Continuously declining reorg rate - Growing blob utilization

Layer 2 Scaling Demand With the rapid development of Layer 2 rollups, the demand for data availability continues to grow: - Major rollups like Optimism, Arbitrum, and Base heavily use blobs - Blob space is often in short supply - More throughput is needed to support L2 ecosystem expansion

Core Content¶

Blob Count Adjustment

Parameter	Dencun (Old)	Pectra (New)
Target blobs/block	3	6
Maximum blobs/block	6	9
Target data/block	~384 KB	~768 KB
Maximum data/block	~768 KB	~1.15 MB

Each blob contains 128 KB of data.

Implementation Details Starting from the Pectra fork epoch:

TARGET_BLOBS_PER_BLOCK_ELECTRA = 6
MAX_BLOBS_PER_BLOCK_ELECTRA = 9

These parameters are used by consensus layer clients, replacing the previous values.

Impact on Layer 2¶

Lower L2 Transaction Fees More blob space means: - Rollups can submit more transaction batches - Data availability costs decrease for L2 users - L2 Gas fees further decline

Higher Throughput Each block can contain more L2 transaction data: - Previous ~384 KB target capacity -> Now ~768 KB - Significant increase in L2 TPS (transactions per second) - Supports more concurrent L2 networks

Reduced Congestion When blob space is tight: - Rollups need to bid for blob space - EIP-7691 increases supply, easing competition - More stable L2 operating costs

Network Impact¶

Bandwidth Requirements Doubling target capacity means: - Nodes need to download more data - Recommended bandwidth: 100 Mbps+ - Relatively small impact on home node operators

Storage Requirements The temporary nature of blob data: - Blobs are retained on the consensus layer for approximately 18 days - Can be pruned afterward (in conjunction with EIP-4444) - Long-term storage pressure is minimal

Validation Load More blobs mean: - More KZG proof verifications - Slightly increased hardware requirements for validators - Still within acceptable range

Implementation Status¶

Activation Information - Upgrade name: Pectra (Prague-Electra) - Activation time: May 7, 2025 at 10:05 UTC - Activation epoch: 364032 - Status: Activated on Ethereum mainnet

Client Support All major Ethereum clients have implemented EIP-7691: - Geth - Nethermind - Besu - Erigon - Prysm (consensus layer) - Lighthouse (consensus layer) - Teku (consensus layer) - Nimbus (consensus layer)

Data Availability Strategy¶

Short-Term Solution EIP-7691 is a temporary throughput increase: - Provides a bridge while waiting for long-term solutions like PeerDAS - Validates network performance under higher loads - Accumulates experience for future scaling

Long-Term Roadmap Ethereum's long-term data availability plan: 1. EIP-4844 (completed): Introduced blob infrastructure 2. EIP-7691 (completed): Increased blob count 3. PeerDAS (in development): Distributed data availability sampling 4. Full Danksharding (future): Full sharded data availability

Relationship with Other Proposals¶

EIP-4844 (Blob Transactions) EIP-7691 builds directly on EIP-4844: - Uses the same blob data structure - Extends blob capacity parameters - Maintains the temporary nature of blob transactions

EIP-4444 (Historical Data Expiry) The two work together to reduce storage burden: - EIP-7691 increases temporary data volume - EIP-4444 deletes historical data - Node storage requirements remain manageable

PeerDAS (Data Availability Sampling) EIP-7691 is a transitional solution before PeerDAS: - PeerDAS will enable much larger-scale data availability - Nodes will not need to download all blobs - Enables truly large-scale scaling

Monitoring Metrics¶

Key Metrics The Ethereum Foundation and community continuously monitor: - Block propagation time: Impact after blob increase - Reorg rate: Network consensus stability - Blob utilization: Actual usage - Node performance: Validator hardware load

Success Criteria If the following metrics remain healthy, further increases may occur in the future: - Reorg rate does not rise - Block propagation delay is acceptable - Node participation rate does not decline

Economic Impact¶

Blob Fee Market More blob supply affects fees: - Blob base fee may decrease - L2 costs decrease accordingly - Still maintains EIP-1559 style dynamic adjustment

Ethereum Economics Impact on the ETH economic model: - Blob fees are burned (destroying ETH) - More blobs may increase ETH burn volume - But unit price may decrease; overall impact remains to be observed

Significance for Users¶

L2 Users Direct benefits: - Lower transaction fees - Faster transaction confirmations - Better L2 user experience

L1 Users Indirect impact: - L1 activity may migrate to cheaper L2s - L1 congestion may ease - Overall Ethereum ecosystem scaling

Developers New possibilities: - Can build higher-throughput L2 applications - Data-intensive applications become feasible - Cross-L2 interoperability improves

Future Outlook¶

Gradual Scaling The Ethereum community adopts an incremental scaling strategy: - First observe the impact of 6/9 blobs - If the network is stable, further increases may follow - Eventually transition to PeerDAS

Ecosystem Evolution EIP-7691 drives ecosystem development: - L2 becomes the primary user interaction layer - L1 focuses on settlement and data availability - Further realization of the Rollup-centric roadmap