A Concurrent Conflict Transaction Optimization Method for Consortium Blockchain Hyperledger Fabric

With the prevalence of blockchain technology, Hyperledger Fabric (Fabric for short), as a well-known open source blockchain platform, has received wide attention. However, Fabric still suffers from conflicts between concurrent transactions. Conflicts will cause a large number of invalid transactions entering the chain, resulting in a decrease in throughput and hindering its development. For this problem, existing intra-block-conflict-oriented schemes lack efficient conflict detection and avoidance methods, and ignore the adverse impact of inter-block conflicts on throughput. We propose an optimization scheme for Fabric, Fabric-HT (Fabric with high throughput), from both intra-block and inter-block aspects to effectively reduce concurrency inter-transaction conflicts and improve system throughput. For intra-block transaction conflicts, we present a transaction scheduling mechanism, in which an efficient data structure (the dependency chain) is defined to identify and abort transactions with “dangerous structures” in advance, reasonably schedule transactions and eliminate conflicts; for inter-block transaction conflicts, the conflict transaction detection is moved to the sorting node to complete, and an early conflict transaction avoidance mechanism following “push-match” pattern is established. A large number of experiments are carried out in multiple scenarios, and the results show that Fabric-HT overperforms existing schemes in terms of throughput, transaction abort rate, average transaction execution time, and invalid transaction space occupancy. The results show that the throughput of Fabric-HT can reach up to 9.51x that of Fabric and 1.18x of the latest optimized scheme FabricSharp; compared with FabricSharp, the space utilization is increased by 14%. In addition, Fabric-HT also shows good robustness and anti-attack ability in solving concurrent transaction conflict.