On Tue, Mar 14, 2017 at 4:28 AM, Kang Minwoo <minwoo.k...@outlook.com> wrote:
> Hi, I am Minwoo. > > I am interesting in HBase Architecture. > So I read Architecting HBase Applications. > > In the book, HBase 2.0 is work in progress to reduce its dependency on > ZooKeeper. > > I want to the reason. > > Why are work in progress in HBase 2.0 to reduce its dependency on > ZooKeeper? > > > Hello Kang Minwoo: We are working to minimize our dependency on zookeeper. Over time, we became lazy and reliant on zookeepers 'availability' using it to store (temporary) state that we wanted to survive the coming and going of servers. But keeping state up in a remote, 3rd party system (on the other side of an RPC) costs (latency, complexity). Going via zk was fine when we had no alternative but with the roll out of our ProcedureV2 'intent' WAL system, there is a purposed, integral mechanism we can use instead. ZooKeeper will be retained to do that for which it is intended, leader election for instance, but intermediate host assignment state will be kept local to the Master persisted in a ProcedureV2 WAL hosted on HDFS, replication offsets will be moved into an hbase table, and so on. Hope this helps, St.Ack > Previously, Invalid email sent. > > I'm really sorry. > > Thanks. >
