wrong result for eth_gasPrice

[sirpy]

Expected Behavior

should return 5gwei or current baseFeePerGas

Actual Behavior

returns 25gwei

Steps to reproduce the behavior

curl https://forno.celo.org/ \
  -X POST \
  -H "Content-Type: application/json" \
  --data '{"method":"eth_gasPrice","params":[],"id":1,"jsonrpc":"2.0"}'

Seems to work fine on Baklava
Chain/Network: Alfajores/Mainnet

[palango]

@sirpy Currently this endpoint returns a suggested gas price that works in the given network condition and not the base fee.

celo-blockchain/contracts/gasprice_minimum/gasprice_minimum.go

Lines 65 to 68 in d8b3680

	func GetGasPriceSuggestion(vmRunner vm.EVMRunner, currency *common.Address) (*big.Int, error) {
	gasPriceMinimum, err := GetGasPriceMinimum(vmRunner, currency)
	return new(big.Int).Mul(gasPriceMinimum, suggestionMultiplier), err
	}

On baklava the values matches your expectation because the base fee is lower (1gwei) and the multipler is 5.

One solution to better handle this would be to create two endpoints, one for the base fee (similar to ethereum) and one for the suggested fee. What do you think about that?

[sirpy]

@palango sure, matching with ethereum standards would be best

[sirpy]

@palango though i dont think on any other network the get gas price returns a multiplier of the current gas costs.
the 5x multiplier is also very very high, it should be something like 1.2
this causes users to pay 5x the gas!

[palango]

@sirpy In the next release you will be able to change the multiplier with the --rpc.gaspricemultiplier option. The default changes two a factor of two, but maybe we will change that on forno.

Further changes to get closer to Ethereum are tracked in #2153

[sirpy]

@palango
I don't think that's a solution as users and dapps dont use their own rpc.
They rely on forno or other providers.
Currently in many celo dapps users are paying 5x for gas

[palango]

@sirpy Yes, we will reduce the multiplier on forno as well, but now people that run their own nodes can also adjust the multiplier themselves.