SC-Chef: Turboboosting Smart Contract Concurrent Execution for High Contention Workloads via Chopping Transactions

Concurrent execution of smart contracts is a promising approach to boost their performance in current blockchain systems. However, prior work on concurrent execution only considered each smart contract transaction as a single atomic unit for the concurrent scheduling, which is not suitable for the increasingly complex smart contracts with high contention in practice. In this article, we present <sc>SC-Chef</sc>, a new concurrency control system to turboboost smart contract concurrent execution for high contention workloads via the transaction decomposition. The key novelty of our <sc>SC-Chef</sc> is to decompose the original transaction into multiple subtransactions that can be executed independently, while still respecting the original logic dependency. We implement and evaluate our <sc>SC-Chef</sc> in the private Ethereum platform. Our extensive experiments show that our <sc>SC-Chef</sc> outperforms the classic optimistic concurrency control and two-phase lock by 60% and 70% on average in the case of high contention, respectively.