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Zheng Hu commented on HBASE-19216: ---------------------------------- bq. First in this issue I will focus on a general framework to execute remote procedure on RS, and in HBASE-19397 Zheng Hu will focus on how to change the peer modification from zk watcher to a call from the RS level. Yeah, Thanks for Duo's work on replication procedure , actually, I'm not familiar with Procedure framework too. Will take some time to read those codes :-) > Implement a general framework to execute remote procedure on RS > --------------------------------------------------------------- > > Key: HBASE-19216 > URL: https://issues.apache.org/jira/browse/HBASE-19216 > Project: HBase > Issue Type: Improvement > Reporter: Duo Zhang > > When building the basic framework for HBASE-19064, I found that the > enable/disable peer is built upon the watcher of zk. > The problem of using watcher is that, you do not know the exact time when all > RSes in the cluster have done the change, it is a 'eventually done'. > And for synchronous replication, when changing the state of a replication > peer, we need to know the exact time as we can only enable read/write after > that time. So I think we'd better use procedure to do this. Change the flag > on zk, and then execute a procedure on all RSes to reload the flag from zk. > Another benefit is that, after the change, zk will be mainly used as a > storage, so it will be easy to implement another replication peer storage to > replace zk so that we can reduce the dependency on zk. -- This message was sent by Atlassian JIRA (v6.4.14#64029)