博文

目前显示的是 六月, 2021的博文

distributed transaction solution - Seata

 Distributed Transaction Solution GTS(Global Transaction Service) ACID XA(eXtended Architecture) X/Open. TM(Transaction Manager), RM(Resource Manager), and Application Manager. XA->2PC(Prepare, commit, rollback)->TCC(Try,Confirm,Canccel)->3PC(CanCommit,PreCommit,DoCommit) Saga , 1987 year, by Hector and Kenneth for Long lived transaction. Princeton University Seata TXC->GTS->Seata->Seata GA TC(Transaction Coordinator),TM(Transaction Manager),RM(Resource Manager). http://seata.io/en-us/docs/overview/what-is-seata.html XID - Transaction ID TC - Transaction Coordinator Maintain status of global and branch transactions, drive the global commit or rollback. TM - Transaction Manager Define the scope of global transaction: begin a global transaction, commit or rollback a global transaction. RM - Resource Manager Manage resources that branch transactions working on, talk to TC for registering branch transactions and reporting status of branch transactions, and driv...

CAP, Consistency, Availability, Partition tolerance & ES, Elastic Search

 CAP, Consistency, Availability, Partition tolerance Consistency Consistency means that all clients see the same data at the same time, no matter which node they connect to. For this to happen, whenever data is written to one node, it must be instantly forwarded or replicated to all the other nodes in the system before the write is deemed ‘successful.’ Availability Availability means that that any client making a request for data gets a response, even if one or more nodes are down. Another way to state this—all working nodes in the distributed system return a valid response for any request, without exception. Partition tolerance A partition is a communications break within a distributed system—a lost or temporarily delayed connection between two nodes. Partition tolerance means that the cluster must continue to work despite any number of communication breakdowns between nodes in the system. From: https://www.ibm.com/cloud/learn/cap-theorem CA: Oracle, My SQL; A...