This topic describes the Enterprise Edition, which is developed by Alibaba Cloud for high-end enterprise users.
The Enterprise Edition adopts a three-node architecture that consists of one master instance and two slave instances. Data is replicated between the master and slave instances through multiple replicas to guarantee data consistency and financial-level reliability.
The Enterprise Edition supports the following DB engine versions, regions, and instance type families:
- Version: RDS for MySQL 5.7.
- Region: contains at least three zones. These zones are China (Hangzhou), China (Shanghai), China (Shenzhen), and China (Beijing).
- Instance type family: Dedicated instance or Dedicated host.
- This version does not support single-zone instances. In the Enterprise Edition, the master instance and two slave instances are deployed in three different zones in the same region.
- For performance purposes, this version does not allow the master and slave instances to be deployed in different regions.
- For performance purposes, this version does not support any large transaction for which the log size exceeds 20 MB.
- The Enterprise Edition provides enterprise-level reliability to help users achieve zero Recovery Point Object (RPO).
- The master instance and two slave instances are deployed in three different equipment rooms in the same city to provide cross-zone disaster tolerance.
The SQL audit function is free for trial use in the RDS for MySQL 5.7 Enterprise Edition.
For more information, see Product editions overview.
High data consistency and availability
Alibaba Cloud has made enormous functional improvements at the kernel level, for example:
- The distributed consistency protocol (Raft) is used to guarantee the reliability and atomicity of multi-node state switching.
- Two data replicas and three log copies are used. When a database transaction is initiated, the system replicates the database transaction logs from the master instance to the two slave instances. The system submits the transaction only when data is successfully written into at least two instances.
- The RDS for MySQL 5.7 Enterprise Edition uses the distributed consistency protocol to manage the submission, rollback, and restoration of transmissions, thereby guaranteeing data consistency.
- On the slave instances, only the transaction logs on which most parties reach agreements are played back. Additionally, parallel replication is used to improve application logging efficiency, and parallel algorithms at the database, table, logic clock, and writeset levels are supported to reduce RTO and guarantee instance availability.