Gas consumption analysis of Ethereum blockchain transactions

In Ethereum blockchain, whenever a transaction of smart contract is executed, transaction fee is charged in terms of Ethers. To calculate the transaction fee, a computational unit, gas is introduced in smart contracts. Gas consumption is calculated against the smart contract source code execution. The transaction initiator sets the gas price against per unit of gas and the total gas limit. If the gas limit is sufficient, the transaction will be mined otherwise it will be reverted. Smart contracts of Ethereum can be written in any high-level language such as Solidity, Vyper, Python, Java and so forth, but Solidity is massively used for smart contracts creation. In this article, we have examined the 5000 transactions of Solidity based smart contracts from Etherscan and performed statistical analysis on opcodes and source code parameters used in these transactions to identify gas costly patterns. Our statistical results (correlation and regression) analyze the relationship of Solidity parameters and opcodes with the gas consumption. Factors causing an increase or decrease in the gas consumption of smart contracts are highlighted in this article. The regression analysis showed that 87.8% of the variability in the response variable (gas consumption) is due to the parameters used in this analysis. Our results will help the smart contract developers to write the gas optimized smart contracts. The results can be beneficial for end users as they will have to pay gas price for less number of gas units.