Vitess 分片与路由治理（Keyspace、VSchema 与 Reshard 验证）

概述Vitess以Keyspace与VSchema管理分片与路由规则。VTGate提供透明路由，Reshard通过VReplication在不中断的情况下迁移数据与流量，实现线性扩展与治理。关键实践与参数Keyspace：sharded=true 与分片边界Vindex：hash 或 lookup 按业务选择路由：VTGate根据主键或索引决定目标分片Reshard：SplitClone/VReplication 进行迁移与切换示例/配置/实现{

"ks_shop": {

"sharded": true,

"tables": {

"orders": {

"column_vindexes": [{ "column": "customer_id", "name": "hash" }]

}

},

"vindexes": {

"hash": { "type": "hash" }

}

}

}

-- 通过VTGate

INSERT INTO orders(id, customer_id, status) VALUES (1001, 42, 'PAID');

SELECT * FROM orders WHERE customer_id = 42;

vtctlclient Reshard ks_shop.orders --source_shards "-80,80-" --dest_shards "-40,40-80,80-c0,c0-" --vreplication

验证分布均衡：统计各分片行数与QPS，观察按 customer_id 的均衡性路由正确：按主键或vindex进行查询写入，命中预期分片迁移一致：Reshard后数据一致，无重复或丢失延迟与错误：迁移期间错误率与延迟受控注意事项VSchema变更需审慎，避免路由规则破坏兼容迁移前进行回滚演练与容量评估结合只读窗口与限流保证迁移稳定监控VReplication与VTGate的资源使用与健康