Alladi Ramakrishnan Hall

An Efficient Framework for Concurrent Execution of Smart Contracts

Sweta Kumari

Technion, Israel

Blockchain platforms such as Ethereum and several others executec omplex transactions in blocks through user-defined scripts known as smart contracts. Normally, a block of the chain consists of multiple transactions of smart contracts which are added by a miner. To append a correct block into the blockchain, miners execute these transactions of smart contracts sequentially. Later the validators serially re-execute the smart contract transactions of the block. If the validators agree with the final state of the block as recorded by the miner, then the block is said to be validated. It is then added to the blockchain using a consensus protocol. In Ethereum and other blockchains that support cryptocurrencies, a miner gets an incentive every time such a valid block is successfully added to the blockchain.

In most of the current day blockchains the miners and validators execute the smart contract trans-actions serially. In the current era of multi-core processors, by employing the serial execution of the transactions, the miners and validators fail to utilize the cores properly and as a result, have poor throughput. By adding concurrency to smart contracts execution, we can achieve better efficiency and higher throughput. We develop an efficient framework to execute the smart contracts transactions concurrently using optimistic Software Transactional Memory systems(STMs) which outperforms the serial executions.