In distributed database systems, as cluster scales grow, efficiency and availability become critical considerations. In a cluster, a common approach to high availability is using replication, but this is inefficient due to its low storage utilization. Erasure coding can provide data reliability while ensuring high storage utilization. However, due to the large number of coding and decoding operations required by the CPU, it is not suitable for some frequently updated data. In order to optimize the storage efficiency of the data in the distributed system without affecting the availability of the data, this paper proposes a data temperature recognition algorithm that can distinguish data tablets and divides data tablets into three types, cold, warm, and hot, according to the frequency of access. Combining three replicas and erasure coding technology, ER-store is proposed, a hybrid storage mechanism for different data types. At the same time, we combined the read-write separation architecture of the distributed database system to design the data temperature conversion cycle, which reduces the computational overhead caused by frequent updates of erasure coding technology. We have implemented this design on the CBase database system based on the read-write separation architecture, and the experimental results show that it can save 14.6%–18.3% of the storage space while meeting the efficient access performance of the system.

中文翻译：

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ER-Store：分布式数据库系统中具有纠删码和复制功能的混合存储机制

在分布式数据库系统中，随着集群规模的增长，效率和可用性成为关键考虑因素。在集群中，一种常见的高可用性方法是使用复制，但由于其存储利用率低，因此效率低下。纠删码可以在保证高存储利用率的同时提供数据可靠性。但是由于CPU需要大量的编解码操作，不适合一些更新频繁的数据。为了在不影响数据可用性的前提下优化分布式系统中数据的存储效率，本文提出了一种能够区分数据片的数据温度识别算法，将数据片分为冷、温、热三种类型，根据访问频率。结合三副本和纠删码技术，ER-store 被提出，一种针对不同数据类型的混合存储机制。同时结合分布式数据库系统的读写分离架构设计了数据温度转换周期，减少了纠删码技术频繁更新带来的计算开销。我们在基于读写分离架构的CBase数据库系统上实现了该设计，实验结果表明，在满足系统高效访问性能的同时，可以节省14.6%~18.3%的存储空间。减少了纠删码技术频繁更新带来的计算开销。我们在基于读写分离架构的CBase数据库系统上实现了该设计，实验结果表明，在满足系统高效访问性能的同时，可以节省14.6%~18.3%的存储空间。减少了纠删码技术频繁更新带来的计算开销。我们在基于读写分离架构的CBase数据库系统上实现了该设计，实验结果表明，在满足系统高效访问性能的同时，可以节省14.6%~18.3%的存储空间。