[
https://issues.apache.org/jira/browse/CASSANDRA-19769?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
David Capwell updated CASSANDRA-19769:
--------------------------------------
Reviewers: Alex Petrov (was: Alex Petrov, David Capwell)
> CEP-15: (Accord) sequence EpochReady.coordinating to allow syncComplete to be
> learned from newer epochs
> -------------------------------------------------------------------------------------------------------
>
> Key: CASSANDRA-19769
> URL: https://issues.apache.org/jira/browse/CASSANDRA-19769
> Project: Cassandra
> Issue Type: Bug
> Components: Accord
> Reporter: David Capwell
> Assignee: David Capwell
> Priority: Normal
> Labels: pull-request-available
> Fix For: NA
>
> Time Spent: 4h 50m
> Remaining Estimate: 0h
>
> When a node is bootstrapping or doing a host replacement it sees several
> epochs before it actually joins the ring, but in Accord we only synchronize
> epoch knowledge to the nodes that have already joined; this means we won’t
> ever synchronize the epochs seen on the new nodes! This becomes a problem
> because it forces these nodes to include far more epochs than required
> (because they don’t know if the peers know the epoch), and may include stale
> epochs that are not possible to reach quorum (such 2 host replacements to the
> same range would cause that historic range to not be able to reach quorum).
> By sequencing EpochReady.coordinating, we have the property that we only mark
> sync complete for epoch=N if and only if epoch=N-1 has done it as well. With
> this, peers are able to recover the past data when a new epoch is seen.
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
---------------------------------------------------------------------
To unsubscribe, e-mail: commits-unsubscr...@cassandra.apache.org
For additional commands, e-mail: commits-h...@cassandra.apache.org
