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Kudos to the raft authors for making distributed consensus accessible. Structuring the presentation in terms of RPCs and making the algorithm well-suited for im

Kudos to the raft authors for making distributed consensus accessible. Structuring the presentation in terms of RPCs and making the algorithm well-suited for implementing replicated state machines may not sound like a big deal, but those decisions really helped to make it approachable. In a span of a decade consensus transformed from an esoteric algorithm that you can maaaaybe try implementing if you are a google engineer, to being widely deployed across many storage systems and readily accessible libraries and Raft played a big part in it.

eatonphil 1y ago
Anyone can implement Raft. There are plenty of implementations of them not by Google engineers, including a custom one in the product I work on. And developers in the Software Internals Discord are constantly in there asking questions on the road to implementing Raft or Viewstamped Replication.
- trenchpilgrim 1y ago
  I believe the parent is referring to pre-raft consensus algorithms like Paxos. I recall the explanation of Paxos being a lengthy PDF while the explanation of Raft is a single webpage, mostly visual.
  - eatonphil 1y ago
    Could be, it was a little ambiguously worded. That said, single-decree Paxos is much simpler than Raft but I agree The Part-Time Parliament's analogy is a pain to read. But it's better if you just ignore the beginning chunk of the paper and read like the appendix; A1 The Basic Protocol being simpler to understand.
    - mananaysiempre 1y ago
      There’s also the side-by-side Paxos/Raft comparison in Howard & Mortier’s “Consensus on consensus”[1] paper, which is not enough to understand either by itself, but a great help if have a longer explanation you’re going through. [1] https://dl.acm.org/doi/10.1145/3380787.3393681 https://dl.acm.org/doi/10.1145/3380787.3393681
  - mrkeen 1y ago
    Other way around. Step 1 of Raft is for the distributed nodes to come to consensus on a fact - i.e. who the leader is. ALL of Paxos is the distributed nodes coming to consensus on a fact. Raft just sounds easier because its descriptions use nice-sounding prose and gloss over the details.
almostgotcaught 1y ago
> if you are a google engineer Do people really have this kind of inferiority complex? What exactly do you think Google engineers are? People with 5 eyes and for hands with 10 fingers each? They read the papers (Paxos or whatever) struggle to understand it, implement beta versions, and iterate just like everyone else.

eatonphil 1y ago

Anyone can implement Raft. There are plenty of implementations of them not by Google engineers, including a custom one in the product I work on. And developers in the Software Internals Discord are constantly in there asking questions on the road to implementing Raft or Viewstamped Replication.

trenchpilgrim 1y ago
I believe the parent is referring to pre-raft consensus algorithms like Paxos. I recall the explanation of Paxos being a lengthy PDF while the explanation of Raft is a single webpage, mostly visual.
- eatonphil 1y ago
  Could be, it was a little ambiguously worded. That said, single-decree Paxos is much simpler than Raft but I agree The Part-Time Parliament's analogy is a pain to read. But it's better if you just ignore the beginning chunk of the paper and read like the appendix; A1 The Basic Protocol being simpler to understand.
  - mananaysiempre 1y ago
    There’s also the side-by-side Paxos/Raft comparison in Howard & Mortier’s “Consensus on consensus”[1] paper, which is not enough to understand either by itself, but a great help if have a longer explanation you’re going through. [1] https://dl.acm.org/doi/10.1145/3380787.3393681 https://dl.acm.org/doi/10.1145/3380787.3393681
- mrkeen 1y ago
  Other way around. Step 1 of Raft is for the distributed nodes to come to consensus on a fact - i.e. who the leader is. ALL of Paxos is the distributed nodes coming to consensus on a fact. Raft just sounds easier because its descriptions use nice-sounding prose and gloss over the details.

almostgotcaught 1y ago

> if you are a google engineer Do people really have this kind of inferiority complex? What exactly do you think Google engineers are? People with 5 eyes and for hands with 10 fingers each? They read the papers (Paxos or whatever) struggle to understand it, implement beta versions, and iterate just like everyone else.