Arbitrum: two-dimensional cost

Arbitrum： Two dimensional costs

In last week's Arbitrum Odyssey period ,Arbitrum One The traffic has reached a record level . Some sharp eyed users found a strange phenomenon ： With L2 Medium gas Rise in price , For a given transaction L2 Medium gas The number will actually decrease .

The fact proved that , This is the working principle of the system , But for laymen , It may look a little chaotic .

Two dimensional costs

In the system of economic design ( Such as Arbitrum) in , We actually pay for two things at the same time ：L1 Native resources and L2 primary resources .Arbitrum One It's a Rollup, We paid L1 Resources are essentially just Ethereum calling data ; in other words , We pay the size of the original data of the transaction times L2 Considered L1 Call data price . What we need to pay for L2 Resources are traded in Arbitrum Common to VM Any calculations performed in —— perform 、 Write storage, etc . The value is L2 Of gas Price times ArbGas(Arbitrum The basic unit of measure ) The number of . What needs to be paid for a successful transaction L2 The total cost is the sum of these two parts .

In a one-dimensional world

The tricky thing is , Even though it's like Arbitrum In this way L2 The cost of is essentially two-dimensional , But the current Ethereum ecosystem is mainly L1 The establishment of a , Its cost can be expressed as one dimension . This means the current infrastructure —— wallet 、 Developer library, etc —— Assume that the transaction format is a single gas Units and individual gas Product of price ; Then we should Arbitrum When trading on , We have to put L1 and L2 Dimensions are crammed into this restrictive format . So what should we do ?

How do we do it ？

To sum up , Our limitation is , The total cost —— Must include L1 and L2 cost —— It needs to be expressed as the product of two values , We call it “ similar gas Price things ”§ and “ similar gas Restricted things ”(G).

We are P Value used （ from Arbitrum Estimation gas Price RPC return ）, in fact , It's just L2 Of gas Price ( Estimate of the gas RPC Added a small percentage of increase buffer ; Any excess will be refunded ).G Express L1 dimension ; call Arbitrum Estimation gas Price RPC Gives a value , For L2 Calculated ArbGas Add an extra buffer (B), such P*G Finally, it is enough to cover all transaction costs . let me put it another way , We added “gas limit” And so on , Make in a given gas The total amount paid under the price is sufficient to cover L1 and L2 Cost of dimension .

Through a little algebraic operation , We found this buffer B Must be equal to (L1 calldata cost)/ P.

So in general ,G Unpack for ：

L2 gas used + ( L1 calldata price * L1 calldata size) / (L2 gas price)

… Among them “L2 gas price” The denominator explains why all other values are equal ,L2 Of gas The increase in price actually reduces G Value .

Towards a two-dimensional charging standard

We are currently trapped in the one-dimensional cost infrastructure supported by the ecosystem at this stage , But ideally , Multidimensional cost standards have been agreed and widely adopted . Here are some suggestions ：https://ethresear.ch/t/multidimensional-eip-1559/11651

Source：https://ethresear.ch/t/multidimensional-eip-1559/11651

About

ChinaDeFi - ChinaDeFi.com It's a research driven DeFi Innovation organizations , We are also a blockchain development team . From all over the world every day 500 Close to a good source of information 900 In the content , Looking for deeper thinking 、 Sort out more systematic content , Provide decision-making assistant materials to the Chinese market at the fastest speed .

Layer 2 friends sharing same hobby - Welcome to Layer 2 Interested blockchain technology enthusiasts 、 Study and analyze people and Gavin（ WeChat : chinadefi） contact , Discuss together Layer 2 Landing opportunities . Please pay attention to our official account of WeChat “ Decentralized financial community ”.