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Marcus Eriksson commented on CASSANDRA-13664: --------------------------------------------- bq. isn't the issue here that the streams aren't weighted Yes, that would be a nicer solution. It wasn't obvious to me how to do maximum bipartite matching with weighted edges though so I went with the easy solution (I guess having an edge for each token would be a way, but that would be quite silly). Also have to say I didn't spend very much time trying to figure it out, so if you have an idea, please let me know. > RangeFetchMapCalculator should not try to optimise 'trivial' ranges > ------------------------------------------------------------------- > > Key: CASSANDRA-13664 > URL: https://issues.apache.org/jira/browse/CASSANDRA-13664 > Project: Cassandra > Issue Type: Bug > Reporter: Marcus Eriksson > Assignee: Marcus Eriksson > Fix For: 4.x > > > RangeFetchMapCalculator (CASSANDRA-4650) tries to make the number of streams > out of each node as even as possible. > In a typical multi-dc ring the nodes in the dcs are setup using token + 1, > creating many tiny ranges. If we only try to optimise over the number of > streams, it is likely that the amount of data streamed out of each node is > unbalanced. > We should ignore those trivial ranges and only optimise the big ones, then > share the tiny ones over the nodes. -- 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