High and variables fees for packets requiring contract calls via ibc-hooks cause operators to pay for more gas

[ancazamfir]

Summary

High and variables fees for packets requiring contract calls via ibc-hooks cause operators to pay for more gas.

Problem Definition

This is from a conversation with @womensrights, cc @ValarDragon (we will fill more details as we investigate the issue and the solutions):

...some problems related to contract calls through ibc-hooks being expensive and highly variable could be resolved through some modifications to hermes.
The issue was that relayers often end up paying more gas than simulated for ibc packets with a contract call through ibc-hooks.

Proposal

Ideally hermes would have a better way to figure out the gas costs for these packets, an initial simple solution would be to increase the multiplier in gas simulation for these packets with a contract call in the memo field but in the future certain contracts could be whitelisted (if they have predicatable gas usage) or I’m sure there are many possibilities.

... [one solution is] just increase the [gas-]multiplier for packets with a memo calling a contract, there is the json key “wasm”, for example txs like this - https://dev.mintscan.io/osmosis/tx/DCB6E301E897C9111F1D89A92B52527208303AAF32B66997B463CFF62297F236?height=13221060

Acceptance Criteria

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For Admin Use

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