EIP-1559 transactions and gasPrice

[makinghappen]

Ethers Version

5.7.2

Search Terms

eip-1559, gasprice

Describe the Problem

in ethers 5.7.2 specifying gasPrice and type:2 EIP-1559 transaction is allowed. But in ethers 6x mixing of transaction properties is not allowed

ethers.js/src.ts/providers/abstract-signer.ts

Line 93 in d74a802

// Do not allow mixing pre-eip-1559 and eip-1559 properties

This leads to confusion, actually specifying gasPrice both with type:2 transaction works better, giving better stability.
Could someone clarify how this works for 5.7.2, and how to make pure EIP-1559 transactions relyable?

Code Snippet

No response

Contract ABI

No response

Errors

No response

Environment

No response

Environment (Other)

No response

[ricmoo]

In v5, supporting gasPrice (which sets both the maxFeePerGas and maxPriorityFeePerGas to gasPrice) had to be supported for backwards compatibility purposes and because EIP-1559 was still having its values tweaked. Originally the maxPriorityFeePerGas was 2.5 gwei (to accommodate uncle risks), lowered to 2 (as MEV risk demonstrated to be less an issue) and finally with PoS, 1 gwei is sufficient.

In v6, we had the opportunity to move away from that bad practice. Using a gasPrice instead of correct fee data is bad for the network and bad of the user. If it were too common, it would push the network back into a bidding-war-based system (where we need gas stations to approximate prices and inclusion times were erratic) and for users, as it results in them paying substantially higher fees. Fees could easily by dozens of times more expensive, based on current network conditions, if using gasPrice today.

It isn't more stable to use gasPrice. Providing a meaningful base fee and a normal priority fee is very stable, and generally result in your transaction occurring in the next block or so. Providing more priority fee can provide stronger incentives, but is largely necessary.

Hope that makes sense?