Raft lecture (Raft user study)

One of the most lucid explanations of the Raft Consensus Algorithm that I've ever seen is the one in John Ousterhout and Diego Ongaro's Raft User Study[0]. The 2 videos do an excellent job of explaining both the Paxos and Raft algorithms and the key differences between them. John's narration is extremely clear and the slides are very informative. Definitely recommended! Raft is a consensus algorithm designed to be easier to understand than Paxos. To measure Raft's understandability, we conducted an experimental study using CS students at two universities. We recorded a video lecture of Raft and another of Paxos, and created corresponding quizzes. This page makes our materials available for anyone interested. We think these are valuable resources for anyone learning consensus (whether Raft or Paxos or both). [0] - [link] Raft Video - ▶ this video Paxos Video - [link]

in “The Raft Consensus Algorithm” · View on HN

This YouTube video by the Raft creators (linked at the bottom of the page) gives a solid explanation of Raft internals - ▶ this video

in “The Raft Consensus Algorithm (2015)” · View on HN

A really good intro to Raft --> ▶ this video Very useful if you are into distributed systems and would like to see a practical implementation with clear examples.

in “The Writings of Leslie Lamport” · View on HN

one other thing to keep in mind is that the underlying algorithms (zab and raft) provide different guarantees. for example, zookeeper/zab allows reading directly from followers with a guarantee to get at least a past value that won't be rolled back. this was one reason zookeer didn't use paxos: [link] in my understanding, raft doesn't allow reading directly from followers, because the follower logs may get repaired/rolled-back when a new leader is elected. (though i'm sure an implementation can tweak the protocol to provide this support.) that said, raft has a lot of interesting applications, and, in my opinion, is definitely more understandable than the many versions of paxos. (implementing zab yourself, at this point, would be a futile exercise.) i found the videos from the raft user study to be very well done (and easier to understand than even their paper): raft: [link] paxos: ▶ this video ...however, i think they did paxos a disadvantage by not just focusing on multi-paxos (which is probably the most common implementation). but, it's certainly fair to say that info about paxos is spread out far and wide...with perhaps too many knobs to turn and implementation-related details to fill in yourself. as a side note: i've just started implementing raft in a set of libraries (multiple languages) that will be open source - along with other protocols.

in “ZooKeeper vs. Doozer vs. Etcd” · View on HN

Raft is very similar to Multi-Paxos. These Raft and Paxos user studies comparing the "understandability" of the two protocols might be helpful: [link] (Paxos), ▶ this video (Raft). See also, comparison of various "Paxos" implementations: [link]

in “Paxos vs. Raft: Have we reached consensus on distributed consensus?” · View on HN

This is a good question. You would recruit actual maintainers, [edit: or whoever is your intended subject pool] (who would provide consent, perhaps be compensated for their time). You could then give them a series of patches to approve (some being bug free and others having vulnerabilities). [edit: specifying the population of a study is pretty important. Getting random students from the University to approve your security patch doesn't make sense. Picking students who successfully completed a computer security course and got a high grade is better than that but again, may not generalize to the real world. One of the most impressive ways I have seen this being done by grad students was a user study by John Ousterhout and others on Paxos vs. Raft. IIRC, they wanted to claim that Raft was more understandable or led to fewer bugs. Their study design was excellent. See here for an example: ▶ this video ]

in ““They introduce kernel bugs on purpose”” · View on HN