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https://issues.apache.org/jira/browse/HBASE-10295?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13961801#comment-13961801
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Enis Soztutar commented on HBASE-10295:
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bq. Make Master arbiter for these new system tables – only the master can mod
them – and then add a response on the heartbeat to update regionservers on last
edit? Could be as simple as master just replying w/ timestamp of last edit.
We should do this as a part of (or using) HBASE-9864. I was thinking of
something similar, where the data is kept in an hbase table as a snapshot +
WAL. All transactions will have an trxid (NO timestamps please). All region
servers open a session with a lease, and keep heartbeats to renew their lease.
They send the last seen trxId, and the coordinator replies with the list of
edits that they should apply to their in memory cache. If some reader looses
it's leases, the coordinator (master) invalidates its session (so that there is
an upper bound on the time the edits will be propogated). The coordinator keeps
the last seen trxId per session, so that it can do recreate the snapshot and
get rid of write ahead log entries.
However, astute readers might have noticed that this is indeed similar to zk's
own protocol except that the data is not replicated via ZAB, but via datanode
pipelines and hbase.
> Refactor the replication implementation to eliminate permanent zk node
> -----------------------------------------------------------------------
>
> Key: HBASE-10295
> URL: https://issues.apache.org/jira/browse/HBASE-10295
> Project: HBase
> Issue Type: Bug
> Components: Replication
> Reporter: Honghua Feng
> Fix For: 0.99.0
>
>
> Though this is a broader and bigger change, it original motivation derives
> from [HBASE-8751|https://issues.apache.org/jira/browse/HBASE-8751]: the newly
> introduced per-peer tableCFs attribute should be treated the same way as the
> peer-state, which is a permanent sub-node under peer node but using permanent
> zk node is deemed as an incorrect practice. So let's refactor to eliminate
> the permanent zk node. And the HBASE-8751 can then align its newly introduced
> per-peer tableCFs attribute with this *correct* implementation theme.
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