Rollup priority-fee setting during blob-market congestion

Establish how rollups set EIP-1559 priority fees during congested periods of the Ethereum blob market, and specifically determine whether these priority fees scale with the number of blobs per type-3 transaction.

Background

Theory suggests that when the blob base fee is in slow price discovery during congestion, competition should shift toward first-price-like bidding via EIP-1559 priority fees that scale with blob usage.

Empirically, the authors’ analysis across rollups (including a focused look at the LayerZero airdrop period) does not provide definitive evidence that rollups adjust priority fees proportionally to the number of blobs, leading to an explicit statement of inconclusiveness.

References

As a result, our analysis is (partially) inconclusive in regard to how the rollups set their priority fees during congested periods but find little to no signs of them doing so.

— The Early Days of the Ethereum Blob Fee Market and Lessons Learnt (2502.12966 - Heimbach et al., 18 Feb 2025) in Appendix B: Priority Fees of Blob Transactions