2014年12月5日 · In comparison to 2PC it requires more messages, but it is resilient to manager failures. In comparison to most 3PC algorithms, Paxos renders a simpler, more efficient algorithm (minimal message delay), and has been proved to be correct. Gray and Lamport compare 2PC and Paxos in an excellent paper titled "Consensus on Transaction Commit".

2015年3月31日 · This problem is – mostly – circumvented by the addition of an extra phase to 2PC, unsurprisingly giving us a three-phase commit protocol. The idea is very simple. We break the second phase of 2PC – ‘commit’ – into two sub-phases. The first is …

2018年2月21日 · 2-phase commit (2PC) Sagas; 2PC is a protocol for applications to transparently utilize global ACID transactions by the support of the platform. Being embedded in the platform, it is transparent to the business logic and the application code as far as I know.

2017年6月7日 · Since 2PC uses only 2 messages, in order to keep the cohorts consistent, the cohorts can never apply a commit without explicitly receiving a COMMIT message. So, when a coordinator crashes, the cohorts can either (1) apply a ABORT using a timeout or (2) can remain in waiting state indefinitely.

2016年2月25日 · The 2PC algo works such that first the coordinator asks all the distributed machines to prepare for the transaction. After receiving a Yes it sends in the command to commit the transaction. If the coordinator receives a success from all the machines only then the transaction is complete otherwise if there is a network outage after that or any ...

2011年1月9日 · Due to blocking nature, 2PC is an overkill in almost any practical situation and a wise design of storage locations and data flows can give a better solution. Basically, you need a unique most authoritative source of any kind of information and all other involved parties must be able to update themselves to that authoritative state.

2019年3月20日 · Check out the related microservices patterns that offer an alternative to XA transactions (you might see this as global transactions or 2 phase commit / 2PC) like Transactional Outbox or Event Sourcing that offer nice at least once semantics. Distributed systems are very complicated and you should have a reason to go for such a solution.

Obviously the cost is 2x against Saga Pattern, but in some cases 2PC could be more interesting than Saga. For example: As a part of a transaction an email is sent, with Saga is not possible revert this, case there is a fail, but with 2PC this is possible (Let's assume this is …

2009年2月13日 · This is not correctly said. 2PC is 100% correct under certain assumptions. For this question, the participant must durably store data from pre-commit and must be able to finish the commit after a restart, if coordinator instructs it to. The coordinator must also durably store the final decision to rollback or commit and retry it, should it fail.

2017年6月1日 · 2PC doesn't always block when Coordinator fails, a system using 2PC only blocks when Coordinator fails whenever anyone read out a prepared(in-doubt) resource. If the commit message(of phase 2) to Participant lost, the Participant's resource stays at prepared state, it must refer to Coordinator to check out what exact state the resource is.