In cassandra production environment, users sometimes build anti-pattern tables and throw queries in inefficient manners.
So I would like to suggest a feature that enables to log slow query.
The feature can help cassandra operators to identify bad query patterns.
Then operators can give advices about queries and data model to users who don't know cassandra so much.
This ticket is related to
CASSANDRA-6226, and I focus on detecting bad query patterns, not aborting them.