Schema push/pull race

When a schema change is made, the coordinator pushes the delta to the other nodes in the cluster. This is more efficient than sending the entire schema. But the coordinator also announces the new schema version, so the other nodes' reception of the new version races with processing the delta, and usually seeing the new schema wins. So the other nodes also issue a pull to the coordinator for the entire schema.

Thus, schema changes tend to become O in the number of KS and CF present.