The dtest topology_test:TestTopology.movement_test is failing on 2.1.0 and 2.1-HEAD. The test, which has been attached, goes through the following workflow:
- Create an unbalanced three node cluster without vnodes
- Create a keyspace with RF=1
- Load data into the cluster
- Flush the cluster with nodetool flush
- Move the tokens around to balance the cluster, using nodetool move
- Run nodetool cleanup
At this point, the test checks that all 10,000 of the originally inserted rows are still there. In 2.0.10 that is true, however in 2.1, only ~4000 rows exist.