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Aleksey Yeschenko commented on CASSANDRA-13569: ----------------------------------------------- Good call. I think the patch is ok, but I personally prefer tracking cleanup to be performed by the runnables themselves in such cases. Also use computeIfAbsent() on CHMs. An untested branch with a follow-up commit pushed to https://github.com/iamaleksey/cassandra/tree/13569-3.0. Please lmk what you think. > 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