区块链星型分片架构通量模型及应用

并行化是区块链扩容方案中最有效的一类方案,现有的并行化方案可根据网络架构分为星型架构与平行架构两类,但是当前的研究工作中,缺少对于星型分片架构方案的性能边界及性能瓶颈影响因素的分析.因此,针对不同的星型分片架构方案抽象出了一种通用的区块链星型分片架构,并对该通用架构中的交易过程进行了量化建模,得到了区块链通量与分片数量的关系,建立了星型分片架构的通量模型.根据建立的星型分片架构通量模型,可以发现星型架构的通量性能存在上限,存在一个最优的分片数量使得系统的通量达到最高,且通量的最大值与主链功能复杂度存在明确的函数关系.基于所提的通量模型,相关的区块链系统可以结合自身方案的设计,平衡分片数量与主链功能复杂度,使得系统通量达到理论上限,因此对于星型并行化方案设计具有重要指导意义.

Throughput Model of Starlike Sharding Structure for Blockchains and Its Applications

Parallelization is one of the most effective blockchain scalability solutions, and the existing parallelization schemes can be classified into two categories, i.e., starlike structure and parallel structure, according to the network structure. However, the current research lacks the analyses of factors affecting the performance boundary and performance bottleneck in starlike sharding structure. To address this problem, this study abstracts a general starlike sharding structure of blockchains for the schemes adopting different starlike sharding structure, and the transaction process in this general structure is quantitatively modeled to derive the relationship between throughput and the number of shards in starlike sharding structure. According to the constructed model, there exists a performance limit in starlike sharding structure and an optimal sharding quantity to maximize the system throughput. An explicit functional relationship exists between the maximal throughput and the functional complexity of the mainchain. With the proposed throughput model, related blockchain systems can balance the number of shards and the functional complexity of the mainchain to reach the theoretical upper limit of system throughput with the consideration of their specific design. Therefore, the work of this study has significant guiding value in the design of the schemes adopting starlike parallelization.