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Aleksey Yeschenko commented on CASSANDRA-13569: ----------------------------------------------- While we are at it; the purpose of a delay before the pull is clear to me - CASSANDRA-5025 explains it all. That said, reusing the same delay we do for bootstrap/recent start - {{MIGRATION_DELAY_IN_MS}} - seems way way too high for purposes of avoiding a push/pull race. I mean, it's whole 60 seconds. It must hurt convergence times in pull cases, and can/should be lowered. Does anyone here see a reason not to? > Schedule schema pulls just once per endpoint > -------------------------------------------- > > Key: CASSANDRA-13569 > URL: https://issues.apache.org/jira/browse/CASSANDRA-13569 > Project: Cassandra > Issue Type: Improvement > Components: Distributed Metadata > Reporter: Stefan Podkowinski > Assignee: Stefan Podkowinski > Fix For: 3.0.x, 3.11.x, 4.x > > > Schema mismatches detected through gossip will get resolved by calling > {{MigrationManager.maybeScheduleSchemaPull}}. This method may decide to > schedule execution of {{MigrationTask}}, but only after using a > {{MIGRATION_DELAY_IN_MS = 60000}} delay (for reasons unclear to me). > Meanwhile, as long as the migration task hasn't been executed, we'll continue > to have schema mismatches reported by gossip and will have corresponding > {{maybeScheduleSchemaPull}} calls, which will schedule further tasks with the > mentioned delay. Some local testing shows that dozens of tasks for the same > endpoint will eventually be executed and causing the same, stormy behavior > for this very endpoints. > My proposal would be to simply not schedule new tasks for the same endpoint, > in case we still have pending tasks waiting for execution after > {{MIGRATION_DELAY_IN_MS}}. -- This message was sent by Atlassian JIRA (v6.4.14#64029) --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@cassandra.apache.org For additional commands, e-mail: commits-h...@cassandra.apache.org