[ https://issues.apache.org/jira/browse/CASSANDRA-19769?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
David Capwell updated CASSANDRA-19769: -------------------------------------- Test and Documentation Plan: new tests Status: Patch Available (was: In Progress) > 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 > > > 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