基于MySQL和DynamoDB的强一致性分布式事务实践

原創

2021-10-11 14:48

方案

优点

缺点

强一致性
无业务侵入

同步阻塞
有限的数据源支持，比如MySQL, ActiveMQ
5.7.7版本前，客户端退出或者服务宕机事务回滚，服务重启binlog丢失问题

两阶段提交

强一致性

延迟：同步阻塞
单点问题：协调者在 2PC 中起到非常大的作用，发生故障将会造成很大影响。特别是在阶段二发生故障，所有参与者会一直等待状态，无法完成其它操作
参与者依赖：任意一个节点失败就会导致整个事务失败

补充事务（TCC）

高可靠
实时高

开发复杂，需带有业务补偿机制
事务状态管理，需要多次DB操作，有一定的性能损失
最终一致性

Saga

易于理解
松耦合，避免服务间依赖关系
实时高

开发复杂，需带有业务补偿机制
最终一致性

Seata

高性能
易于使用
支持AT, TCC, SAGA, XA 模式

改造成本大：相关程序都要加入Seata事务

性能损失：Seata本身存在一定的性能损耗"}}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"结合Freewheel强一致性业务需求，多数据源分布式事务将由XA、2PC和Seata这些解决方案组合而成。"}]},{"type":"bulletedlist","content":[{"type":"listitem","attrs":{"listStyle":null},"content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"Seata 框架设计思想"}]}]},{"type":"listitem","attrs":{"listStyle":null},"content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"基于 XA 的 Aurora 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Operation

Other Operation

Isolation Level

DisTxDAL

可序列化

DisTxDAL

DAL DDB write interface

可序列化

DisTxDAL

DAL DDB read interface

读取已提交|读取未提交（可选）"}}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}},{"type":"strong"}],"text":"更新接口实现方法"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" 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