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This paper is deliberately a generalization of all of them, actually. Raft can also be explained in terms of the rules/system she provides. She happens to use

This paper is deliberately a generalization of all of them, actually. Raft can also be explained in terms of the rules/system she provides. She happens to use PaxOS as examples to show they are non-optimal, in part because Raft is already deliberately non-optimal. The other reason is that Raft is completely trivial in her framework. It is equivalent to only having one thing decide the registers (and all the hard work is in deciding which thing).

thecupisblue 8y ago
Exactly this, not sure why people think it's a different thing - just wrap nodes into a higher level of abstraction. I believe Raft might be a better approach to scalable consensus tho but there needs to be more layers to a network so the network can be more self-balancing and localised. If we we call "heartbeat" the frequency at which a node is synced to the network (achieves consensus) - lower heartbeat nodes need to stay close only to nodes with a "heartbeat" faster than theirs and elect leaders in that group. The leaders in that group are also in a group of other leaders of that layer and listening to their leader, which belongs to a group above (like zooming out from a group and the group becoming a node in a larger graph). In the end, there is only one state after all and the graph is the ultimate leader with the highest heartbeat. We wouldn't need many layers to cover all nodes, assuming laws of nature and all. Then just go a layer up/down if the network is getting too large, use a karmic system to position new/reactivated nodes. Seems scalable enough. Sorry OP, it might be too early and I'm just thinking out loud in a comment box.
yxhuvud 8y ago
Can the framework model the leader election though?
- DannyBee 8y ago
  They do, effectively. They show what is necessary for quorums, and show that a large number of algorithms meet these requirements. Hence, the single leader election is not actually necessary (and this is one of their points - the existing algorithms require much stronger quorum guarantees than are actually necessary for correctness)
fanf2 8y ago
By the way, Paxos is the name of a Greek island; it doesn’t have funky capitalisation. The name is from Lamport’s paper “the part-time parliament” which describes the algorithm in the setting of Ancient Greece.

thecupisblue 8y ago

Exactly this, not sure why people think it's a different thing - just wrap nodes into a higher level of abstraction. I believe Raft might be a better approach to scalable consensus tho but there needs to be more layers to a network so the network can be more self-balancing and localised. If we we call "heartbeat" the frequency at which a node is synced to the network (achieves consensus) - lower heartbeat nodes need to stay close only to nodes with a "heartbeat" faster than theirs and elect leaders in that group. The leaders in that group are also in a group of other leaders of that layer and listening to their leader, which belongs to a group above (like zooming out from a group and the group becoming a node in a larger graph). In the end, there is only one state after all and the graph is the ultimate leader with the highest heartbeat. We wouldn't need many layers to cover all nodes, assuming laws of nature and all. Then just go a layer up/down if the network is getting too large, use a karmic system to position new/reactivated nodes. Seems scalable enough. Sorry OP, it might be too early and I'm just thinking out loud in a comment box.

yxhuvud 8y ago

Can the framework model the leader election though?

DannyBee 8y ago
They do, effectively. They show what is necessary for quorums, and show that a large number of algorithms meet these requirements. Hence, the single leader election is not actually necessary (and this is one of their points - the existing algorithms require much stronger quorum guarantees than are actually necessary for correctness)

fanf2 8y ago

By the way, Paxos is the name of a Greek island; it doesn’t have funky capitalisation. The name is from Lamport’s paper “the part-time parliament” which describes the algorithm in the setting of Ancient Greece.