Hello, Anyone familer with Paxos protocol here? I was doing some comparision of ZAB vs Paxos... first of all, ZAB's FIFO based protocol is really cool!
http://wiki.apache.org/hadoop/ZooKeeper/PaxosRun mentioned the inconsistency case for Paxos("the state change B depends upon A, but A was not committed"). In the "Paxos made simple" paper, author suggests fill the GAP (lost state machine changes) with "NO OP" opeartion. Now I have some serious doubts how could Paxos be any useful in the real world. yeah you do reach the consesus - albeit the content is inconsistent/corrupted !? E.g. on the wiki page, why the Paxos state machine allow fire off 27,28 concurrently where there is actually depedency? Shouldn't you wait instance 27 to be committed before start 28? Did I miss something? Thanks for the enlight! Cheers Qing