Gas Optimization Bounty submission #1 #452
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* Update Struct `Staker` * uint256 amountStake => uint64 amountStaked * uint256 conditionIdOflastUpdate => uint64 conditionIdOflastUpdate * uint256 timeOfLastUpdate => uint128 timeOfLastUpdate * Other associated changes to facilitate use of updated struct * Remove `stakersArray` and reorder varibles `stakersArray` does not appear to serve any purpose other than to allow for easy off-chain retreival of all staked users. Moving the declaration of indexArray below the non-dynamic variables allows for more efficient variable packing. This saves ~2K gas on the staking function. * Remove ownership and approval check from `_stake` The removed checks are included in all modern ERC721 implementations. If a project removes them from their ERC721 contract, they should override the `_stake` function and include them there. However, in most instances, it is redundant to include them in `_stake`. * linting * run yarn gas * update gas report to ensure accuracy
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@nkrishang @WhiteOakKong hey guys I'm looking to learn from this. Would you explain why we can shift from using uint256 to uint64/128 etc ? |
Depending on the context of the specific variable, you may be able to use a size less than uint256. For instance, in this NFT staking contract, we can make a reasonable assumption that a user is not going to have > unit64.max() (a value of ~18 quintillion) tokens to stake. Similarly with the timestamp, uint128.max() allows for functionality well into the future, beyond what would reasonably be needed for this contract (or the planet...). |
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Beautiful. Thank you for the explanation! |
Summary
gasreport.txtgasreport.txtOverall gas reduced in target contracts: 9.26 %
Total before:
725_049after:657_895(ref:src/test/benchmark/NFTStakeBenchmark.t.sol)