right and make it fast. ● 测试很重要 ● 简单易用 ● 和社区结合 架构 TiKV TiKV TiKV TiKV Raft Raft Raft TiDB TiDB TiDB ... ... ... ... ... Placement Driver (PD) Control flow: Balance / Failover Metadata / Timestamp Storage stack 1/2 ● TiKV is the underlying storage layer ● Physically, data is stored in RocksDB ● We build a Raft layer on top of RocksDB ○ What is Raft? ● Written in Rust! TiKV API (gRPC) Transaction 2:[d-e] split 分裂: 1/4 TiKV1 Region 1:[a-e] TiKV2 Region 1:[a-e] TiKV3 Region 1:[a-e] raft raft Leader Follower Follower Raft group 分裂: 2/4 TiKV2 Region 1:[a-e] TiKV3 Region 1:[a-e] raft

Google Spanner Google F1 TiDB RDBMS NoSQL NewSQL Architecture TiKV TiKV TiKV TiKV Raft Raft Raft TiDB TiDB TiDB ... ... Placement Driver (PD) Control flow: Balance / Failover Metadata / Timestamp request Distributed Storage Layer ... TiKV - Overview • Region: a set of continuous key-value pairs • Data is organized/stored/replicated by Regions • Highly layered TiKV Key Space [ start_key, end_key) Raft 256MB PD - Overview TiKV TiKV TiKV TiKV … ... TiKV Cluster PD Node/Region Info Management Command TiKV Client Route Info ● Meta data management ● Load balance management TiKV - Multi-Raft

副标题 TiDB TiDB Worker Spark Driver TiKV Cluster (Storage) Metadata TiKV TiKV TiKV MySQL Clients Syncer Data location Job TiSpark DistSQL API TiKV TiDB TSO/Data location Worker Worker Worker Spark Cluster TiDB Cluster TiDB ... ... ... DistSQL API PD PD PD Cluster TiKV TiKV TiDB PD 天下大势，合久必分，分久必合 《三国演义》 图 + 关系型多模实现 01. 副标题 g_prefix Vertex_ID Tag_ID g_prefix src_Vertex_ID

= _Pc // Pc is the set of Unicode characters in category Pc. Pd = _Pd // Pd is the set of Unicode characters in category Pd. Pe = _Pe // Pe is the set of Unicode characters in category "Mn": Mn, "N": N, "Nd": Nd, "Nl": Nl, "No": No, "P": P, "Pc": Pc, "Pd": Pd, "Pe": Pe, "Pf": Pf, "Pi": Pi, "Po": Po, "Ps": Ps, "S": S, "Sc": Sc 79 Found: 80 pd, err := fd.Stat() 81 if err != nil { 82 return "", err 83 } 84 fd.Close() 85 if SameFile(pd, root) { 86 break