Efficiency Choice: NetEase Internal Evaluation of Distributed Database TiDB

The article, originally written by NetEase DBA expert Ni Shan‑san, introduces TiDB as a leading open‑source distributed database and explains why the NetEase DBA team decided to evaluate it against their existing MySQL + DDB solution.

It outlines the fundamental requirements for a distributed database—full SQL/DDL support, transactional guarantees, unified cluster entry, horizontal scalability, and high availability—and shows how TiDB meets or exceeds these criteria.

Key advantages of TiDB over the traditional stack are enumerated, including comparable horizontal scaling, superior SQL support, finer‑grained resource scaling, more efficient online DDL, better replication performance, higher consistency, automatic failover, and HTAP capabilities that enable real‑time analytics.

The article also discusses TiDB’s limitations (e.g., lack of stored procedures, foreign keys, certain MySQL‑specific syntax) and notes that these do not impact NetEase’s workloads because their current DDB middleware already lacks many of those features.

Operational benefits are highlighted: TiDB’s stateless servers simplify horizontal scaling and shrinking, and its Raft‑based replication provides strong consistency and rapid failover, dramatically reducing expansion time from days to minutes.

Storage cost analysis shows that TiDB can save 25%‑50% of hardware expenses through reduced RAID requirements and built‑in compression.

HTAP (Hybrid Transactional/Analytical Processing) is presented as a major innovation, allowing TiDB to serve both OLTP and OLAP workloads without separate data pipelines.

Practical deployment scenarios are recommended, such as handling seasonal traffic spikes, high‑availability‑critical services, multi‑center architectures, and workloads that benefit from HTAP.

Migration strategies are described, including CDC‑based real‑time sync from DDB/MySQL to TiDB, bidirectional replication for rollback safety, and phased rollout with read‑only traffic before full cut‑over.

Operational tooling (Prometheus, Grafana, backup/recovery, scaling automation) is already integrated, and the team reports successful internal pilots in payment and music services.

In conclusion, the NetEase DBA team believes TiDB meets all operational, performance, and cost criteria to become a core component of their database ecosystem.