[ https://issues.apache.org/jira/browse/CASSANDRA-15600?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Ekaterina Dimitrova updated CASSANDRA-15600: -------------------------------------------- Test and Documentation Plan: In the cases where the keyspace replication factor is ONE, or if the keyspace replication factor is equal to the number of racks in the datacenter, the workload variance drops from ~10 percent to ~6 percent due to algorithmic optimizations. Status: Patch Available (was: In Progress) > Algorithmic token allocation does not handle the racks = RF case well > --------------------------------------------------------------------- > > Key: CASSANDRA-15600 > URL: https://issues.apache.org/jira/browse/CASSANDRA-15600 > Project: Cassandra > Issue Type: Bug > Components: Feature/Virtual Nodes > Reporter: Branimir Lambov > Assignee: Ekaterina Dimitrova > Priority: Normal > Attachments: CASSANDRA-15600 unit.txt, CASSANDRA-15600-jvm.txt.zip, > Screen Shot 2020-03-02 at 6.55.41 PM.png > > > When the number of racks in a data centre is equal to the replication factor, > the node allocation algorithm may calculate the target ownership incorrectly > and allocate unsuitable tokens. This causes some inefficiency when the number > of nodes in the DC is small, and significant problems if the number of nodes > in each rack is different. > In this case (racks count equal to replication factor) the load within each > rack is effectively distributed independently. The allocation algorithm > should reflect that, restricting the allocation space to the rack (instead of > the DC) and using the RF=1 solution. -- This message was sent by Atlassian Jira (v8.3.4#803005) --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@cassandra.apache.org For additional commands, e-mail: commits-h...@cassandra.apache.org