Heroku’s Doozer “Doozer is where you put the family jewels.” Example use cases: • Database master election • Name service • Configuration What is it good for? 4 Google Confidential Heroku’s Doozer

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 raft Leader Follower Follower TiKV1 Region 1.1:[a-c] 1:[a-c] Region 1.2:[d-e] Leader Follower Follower Split log (replicated by Raft) Split log TiKV2 Region 1:[a-e] TiKV3 Region 1:[a-e] 分裂: 4/4 TiKV1 Region 1.1:[a-c] Leader Region 1.2:[d-e] TiKV2 ● PD 周期性根据 Cache 中的集群信息，生成调度计划（Operator） ● Operator 是作用于一个 Region 的一系列操作 ○ Transfer Leader：将 raft group 的 leader 转让给某个 Peer ○ Add Peer：向 raft group 添加一个副本 ○ Remove Peer：移除 raft group 中的一个副本 ● PD 收到

Region 3 Node A Node B Node E Node C Node D Add Replica Three steps to move a leader replica ● Transfer Leader ● Add Replica ● Remove Replica SQL Layer Example - SQL CREATE TABLE t (c1 INT,

领导选举: 心跳机制来触发选举, term 充当逻辑时钟的作用 日志复制: 领导者把一条指令(能被复制状态机执行)附加到日志中，发起附加条目 RPC 请求 给其他角色 强领导者：日志条目只从 leader 发送给其他的服务器 2017/8/3 基于 mesos 的容器调度框架 http://go-talks.appspot.com/github.com/huangnauh/slides/upone

N+2 CPU Work Frame N+2 GPU Work Frame N+1 GPU Work Frame N+2 CPU and GPU works together as a leader-follower relationship, CPU is responsible for preparing the GPU work and relevant resources, and

fundamental synchronization primitive: compare-and-set. Example use cases: • Database master election • Name service • Configuration Why Go was chosen and how did Go’s characteristics make it a

BTW, the cartoon gopher is designed by Renee French, who is the wife of the (first) Go project leader, Rob Pike. (The Go 101 book is still being improved frequently from time to time. Please visit

BTW, the cartoon gopher is designed by Renee French, who is the wife of the (first) Go project leader, Rob Pike. (The Go 101 book is still being improved frequently from time to time. Please visit

BTW, the cartoon gopher is designed by Renee French, who is the wife of the (first) Go project leader, Rob Pike. (The Go 101 book is still being improved frequently from time to time. Please visit