The name CursorMetrics makes sense for read commands, which may generate a cursor. However, we would also like to collect these metrics for query stats associated with writes. Writes do not generate a cursor, but still need to make use of the similar metrics. In order to keep the code organized and intuitive, we should consider renaming CursorMetrics to QueryStatsMetrics. This is not on the critical path and could be deferred.

Since this field is used in communication between nodes, we can't completely get rid of it. We should add additional fields in the meantime and require just one to be populated, and remove the old field in a subsequent release.