Raft及在NewSQL中的应用

1、Raft及在NewSQL中的应用技术创新，变革未来ContentsWhat is transactionWhat is consistencyWhat is NewSQLWhat is RaftHow Raft worksSummaryWhat is NewSQLNewSQLWhat is transactionAtomicityrequires that each transaction be “all or nothing”Consistencythe consistency property ensures that any transaction will bring the data

2、base from one valid state to anotherIsolation the isolation property ensures that the concurrent execution of transactions results in a system state that would be obtained if transactions were executed serially, i.e., one after the otherDurabilitythe durability properity that once transaction has be

3、en commited, it will remain so, even in the event of power less, crashes or errorsWhat is consistency(CAP)Cconsistency equivalent to having a single up-to-date cope of data.Ahigh availability of that dataP tolerance to network partitionsDistribution MySQL ClusterAn example of NewSQL ArchitectureTran

4、saction Serializable ScheduleIsolationTransaction Serializable ScheduleIsolationTwo-Phase commit protocolAtomicityConsistency(CAP)DurabilityConsistency(CAP)DurabilityState machineM = (Q, , , q0, F)Q = q0, q1, q2 = 0, 1 : Q Qq0= q0F = q2match：1*0+1(0|1)*Q01q0q1q0q1q0q2q2q2q2What is raftraft is an sim

5、ple and understandability consensus algorithmLeader electionLog replicationSafetyReplicated state machineServer StateTerm & log indexLog replicationLog replicationIf two entries in different logs have the same index andterm, then they store the same command.If two entries in different logs have the same index and term, then the logs are identical in all preceding entries.Log replicationSummaryHow to support distribution transaction in NewSQL ?Atomicity Two-Phase commit protocol Consistency the same as in SQL Isolation Global Ti