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 ignores the adverse impact of inter-block conflicts on throughput. This paper proposes 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, this paper proposes 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, and 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.