Multinational enterprises conduct global business that has a demand for geo-distributed transactional databases. Existing state-of-the-art databases adopt a sharded master-follower replication architecture. However, the single-master serving mode incurs massive cross-region writes from clients, and the sharded architecture requires multiple round-trip acknowledgments (e.g., 2PC) to ensure atomicity for cross-shard transactions. These limitations drive us to seek yet another design choice. In this paper, we propose a strongly consistent OLTP database GeoGauss with full replica multi-master architecture. To efficiently merge the updates from different master nodes, we propose a multi-master OCC that unifies data replication and concurrent transaction processing. By leveraging an epoch-based delta state merge rule and the optimistic asynchronous execution, GeoGauss ensures strong consistency with light-coordinated protocol and allows more concurrency with weak isolation, which are sufficient to meet our needs. Our geo-distributed experimental results show that GeoGauss achieves 7.06X higher throughput and 17.41X lower latency than the state-of-the-art geo-distributed database CockroachDB on the TPC-C benchmark.

翻译：跨国企业开展全球业务时，需要地理分布式事务数据库的支持。现有先进数据库采用分片主从复制架构，但单主服务模式导致客户端产生大量跨区域写入操作，而分片架构要求多次往返确认（如2PC协议）来保证跨分片事务的原子性。这些限制促使我们探索另一种设计方案。本文提出一种采用全副本多主架构的强一致性OLTP数据库GeoGauss。为高效合并不同主节点的更新，我们提出一种多主乐观并发控制（OCC）机制，将数据复制与并发事务处理相统一。通过基于时间轮的增量状态合并规则与乐观异步执行策略，GeoGauss以轻协调协议确保强一致性，并通过弱隔离度提升并发能力，能够满足实际应用需求。地理分布式实验结果表明，在TPC-C基准测试中，GeoGauss的吞吐量较现有先进地理分布式数据库CockroachDB提升7.06倍，延迟降低17.41倍。