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Questions tagged [paxos]

Paxos is a family of protocols for a network of unreliable processors to agree on a result.

132 questions
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Differences between OT and CRDT

Can someone explain me simply the main differences between Operational Transform and CRDT? As far as I understand, both are algorithms that permits data to converge without conflict on different nodes of a distributed system. In which usecase would…
Sebastien Lorber
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Paxos vs two phase commit

I am trying to understand the difference between paxos and two phase commit as means to reach consensus among multiple machines. Two phase commit and three phase commit is very easy to understand. It also seems that 3PC solves the failure problem…
Keeto
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Whats the difference between Paxos and W+R>=N in Cassandra?

Dynamo-like databases (e.g. Cassandra) can enforce consistency by means of quorum, i.e. a number of synchronously written replicas (W) and a number of replicas to read (R) should be chosen in such a way that W+R>N where N is a replication factor. On…
user1128016
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Conflict-free Replicated Data Types (CRDT) vs Paxos or Raft

When is it a good idea to use something like CRDT instead of paxos or raft?
Eric des Courtis
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Contradiction in Lamport's Paxos made simple paper

Phase 2. (a) If the proposer receives a response to its prepare requests (numbered n) from a majority of acceptors, then it sends an accept request to each of those acceptors for a proposal numbered n with a value v, where v is the value of the…
lambda
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When to use Paxos (real practical use cases)?

Could someone give me a list of real use cases of Paxos. That is real problems that require consensus as part of a bigger problem. Is the following a use case of Paxos? Suppose there are two clients playing poker against each other on a poker…
user782220
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paxos vs raft for leader election

After reading paxos and raft paper, I have following confusion: paxos paper only describe consensus on single log entry, which is equivalent the leader election part of the raft algorithm. What's the advantage of paxos's approach over the simple…
Oliver Young
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What are the faster Paxos-related algorithms for consensus in distributed systems?

I've read Lamport's paper on Paxos. I've also heard that it isn't used much in practice, for reasons of performance. What algorithms are commonly used for consensus in distributed systems?
Rob Lachlan
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Questions about Paxos implementation

I am implementing Paxos in a cluster simulator application, using the documentation available in Wikipedia. Unfortunately, it leaves several doors open to interpretation and does not provide much information on key implementation issues. It is…
Jérôme Verstrynge
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Real world example of Paxos

Can someone give me a real-world example of how Paxos algorithm is used in a distributed database? I have read many papers on Paxos that explain the algorithm but none of them really explain with an actual example. A simple example could be a…
sjg
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Why is multi-paxos called multi-paxos?

Why multi-paxos is called multi-paxos? I can't see how it is "multi".
onfire
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Why is Paxos leader election not done using Paxos?

The questions below are intended to be serious rather than frivolous. I lack experience in distributed systems, but I do understand how Basic Paxos works and why leader selection is useful. Unfortunately, my understanding is not deep enough to…
merlin2011
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Using Paxos in dynamic environment

Paxos algorithm can tolerate up to F failures when using 2F + 1 processors. As far as I understand, this algorithm works only with fixed number of processors. Is it possible to use this algorithm in dynamic environment, where nodes can be added and…
Evgeny Lazin
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Is operation in raft log entry supposed to be idempotent?

In raft, when a node restart, it try to redo all the log entries to catch up the state. But if node goes down again in recovery phase, node would do some op twice. These twice redo op will violate state machine if ops are not idempotent. According…
smxxqjl
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What to do if the leader fails in Multi-Paxos for master-slave systems?

Backgound: In section 3, named Implementing a State Machine, of Lamport's paper Paxos Made Simple, Multi-Paxos is described. Multi-Paxos is used in Google Paxos Made Live. (Multi-Paxos is used in Apache ZooKeeper). In Multi-Paxos, gaps can…
hengxin
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