make MaxTxGasWanted configurable

[yihuang]

Description

Closes: #1003

Solution:

• add config item: evm.max-tx-gas-wanted

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[codecov]

Codecov Report

Merging #1004 (d559025) into main (93a57bc) will increase coverage by 0.01%.
The diff coverage is 81.81%.

@@            Coverage Diff             @@
##             main    #1004      +/-   ##
==========================================
+ Coverage   59.13%   59.15%   +0.01%     
==========================================
  Files          79       79              
  Lines        6534     6539       +5     
==========================================
+ Hits         3864     3868       +4     
- Misses       2452     2453       +1     
  Partials      218      218              

Impacted Files	Coverage Δ
server/config/config.go	21.34% <50.00%> (+0.35%)	⬆️
app/ante/eth.go	82.42% <100.00%> (+0.05%)	⬆️
app/ante/handler_options.go	77.94% <100.00%> (ø)
app/app.go	85.49% <100.00%> (+0.06%)	⬆️

[zmanian]

This doesn't really solve the issue.

On evmos right now, 80% of tx volume is logic of " test if arb is profitable, if profitable arb otherwise revert". This results in a 7x ratio between gas wanted and gas used which then results in full blocks.

This is what we originally discussed for this scenario.

cosmos/cosmos-sdk#2150

Gas should be charged at max(gas_used, gas_wanted/2)

You may want to just do this in the ethermint ante handler.

[yihuang]

Gas should be charged at max(gas_used, gas_wanted/2)

Do you mean only refund gas_wanted - max(gas_used, gas_wanted/2) at the end of tx processing?

gas_wanted - max(gas_used, gas_wanted/2) == min(gas_wanted - gas_used, gas_wanted / 2)

[yihuang]

This doesn't really solve the issue.

On evmos right now, 80% of tx volume is logic of " test if arb is profitable, if profitable arb otherwise revert". This results in a 7x ratio between gas wanted and gas used which then results in full blocks.

This is what we originally discussed for this scenario.

cosmos/cosmos-sdk#2150

Gas should be charged at max(gas_used, gas_wanted/2)

You may want to just do this in the ethermint ante handler.

#1085

I opened an issue here following your suggestion, summarize the consequences of this as I understand.