I'm curious about what exactly the consensus requirement and assumptions are for the monitors. For instance, in the discussion between Loic and Joao, this statement: Joao: : the recovery logic in our implementation tries to aleviate the burden of recovering multiple versions at the same time. We propose a version, let the peons accept it, then move on to the next version. On ceph, we only provide one value at a time. seems to indicate that the leader is proposing changes sequentially. However, that makes Ceph's use of paxos sound a lot like the reason for the development of the Zab protocol used in Zookeeper: https://cwiki.apache.org/confluence/display/ZOOKEEPER/Zab+vs.+Paxos Either way, as a testament to its understandability, or maybe just its cool factor, there are a lot of Raft reference implementations listed on this page: https://ramcloud.stanford.edu/wiki/display/logcabin/LogCabin On Fri, Sep 13, 2013 at 11:39 PM, Loic Dachary <loic@xxxxxxxxxxx> wrote: > Hi, > > Ceph ( http://ceph.com/ ) relies on a custom implementation of Paxos to provide exabyte scale distributed storage. Like most people recently exposed to Paxos, I struggle to understand it ... but will keep studying until I get it :-) When a friend mentionned Raft ( http://en.wikipedia.org/wiki/Raft_%28computer_science%29 ), it looked like an easy way out. But it's very recent and I would very much appreciate your opinion. Do you think it is a viable alternative to Paxos ? > > Cheers > > -- > Loïc Dachary, Artisan Logiciel Libre > All that is necessary for the triumph of evil is that good people do nothing. > -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
