bastion-rs / artillery

Fire-forged cluster management & Distributed data protocol
https://artillery.bastion-rs.com
Apache License 2.0
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Documentation on how Artillery implements the coordination service from the CRAQ paper. #54

Open epsniff opened 2 years ago

epsniff commented 2 years ago

After discovering this project, I then found the CRAQ paper and began reading it. In that paper, I noticed this paragraph:

Building a fault-tolerant coordination service for distributed applications is notoriously error prone. An 
earlier version of CRAQ contained a very simple, centrally controlled coordination service that maintained 
membership management. We subsequently opted to leverage ZooKeeper however, to provide CRAQ 
with a robust, distributed, high-performance method for tracking group membership and an easy way to 
store chain metadata. Through the use of Zookeper, CRAQ nodes are guaranteed to receive a 
notification when nodes are added to or removed from a group. Similarly, a node can be notified when 
metadata in which it has expressed interest changes.

I've noticed in other implementations of CRAQ, I've seen them replace ZooKeeper with protocols like RAFT. Effectively using Raft for the coordination service and CRAQ for k/v storage.

How does Artillery maintain chain metadata for the cluster? Or is it only using epidemic protocals to distribute metadata?